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Sample records for hiv-derived t-lymphocyte epitopes

  1. Common antiviral cytotoxic t-lymphocyte epitope for diverse arenaviruses.

    PubMed

    Oldstone, M B; Lewicki, H; Homann, D; Nguyen, C; Julien, S; Gairin, J E

    2001-07-01

    Members of the Arenaviridae family have been isolated from mammalian hosts in disparate geographic locations, leading to their grouping as Old World types (i.e., lymphocytic choriomeningitis virus [LCMV], Lassa fever virus [LFV], Mopeia virus, and Mobala virus) and New World types (i.e., Junin, Machupo, Tacaribe, and Sabia viruses) (C. J. Peters, M. J. Buchmeier, P. E. Rollin, and T. G. Ksiazek, p. 1521-1551, in B. N. Fields, D. M. Knipe, and P. M. Howley [ed.], Fields virology, 3rd ed., 1996; P. J. Southern, p. 1505-1519, in B. N. Fields, D. M. Knipe, and P. M. Howley [ed.], Fields virology, 3rd ed., 1996). Several types in both groups-LFV, Junin, Machupo, and Sabia viruses-cause severe and often lethal human diseases. By sequence comparison, we noted that eight Old World and New World arenaviruses share several amino acids with the nucleoprotein (NP) that consists of amino acids (aa) 118 to 126 (NP 118-126) (RPQASGVYM) of LCMV that comprise the immunodominant cytotoxic T-lymphocyte (CTL) epitope for H-2(d) mice (32). This L(d)-restricted epitope constituted >97% of the total bulk CTLs produced in the specific antiviral or clonal responses of H-2(d) BALB mice. NP 118-126 of the Old World arenaviruses LFV, Mopeia virus, and LCMV and the New World arenavirus Sabia virus bound at high affinity to L(d). The primary H-2(d) CTL anti-LCMV response as well as that of a CTL clone responsive to LCMV NP 118-126 recognized target cells coated with NP 118-126 peptides derived from LCMV, LFV, and Mopeia virus but not Sabia virus, indicating that a common functional NP epitope exists among Old World arenaviruses. Use of site-specific amino acid exchanges in the NP CTL epitope among these arenaviruses identified amino acids involved in major histocompatibility complex binding and CTL recognition.

  2. Identification of cytotoxic T lymphocyte epitopes on swine viruses: multi-epitope design for universal T cell vaccine.

    PubMed

    Liao, Yu-Chieh; Lin, Hsin-Hung; Lin, Chieh-Hua; Chung, Wen-Bin

    2013-01-01

    Classical swine fever (CSF), foot-and-mouth disease (FMD) and porcine reproductive and respiratory syndrome (PRRS) are the primary diseases affecting the pig industry globally. Vaccine induced CD8(+) T cell-mediated immune response might be long-lived and cross-serotype and thus deserve further attention. Although large panels of synthetic overlapping peptides spanning the entire length of the polyproteins of a virus facilitate the detection of cytotoxic T lymphocyte (CTL) epitopes, it is an exceedingly costly and cumbersome approach. Alternatively, computational predictions have been proven to be of satisfactory accuracy and are easily performed. Such a method enables the systematic identification of genome-wide CTL epitopes by incorporating epitope prediction tools in analyzing large numbers of viral sequences. In this study, we have implemented an integrated bioinformatics pipeline for the identification of CTL epitopes of swine viruses including the CSF virus (CSFV), FMD virus (FMDV) and PRRS virus (PRRSV) and assembled these epitopes on a web resource to facilitate vaccine design. Identification of epitopes for cross protections to different subtypes of virus are also reported in this study and may be useful for the development of a universal vaccine against such viral infections among the swine population. The CTL epitopes identified in this study have been evaluated in silico and possibly provide more and wider protection in compared to traditional single-reference vaccine design. The web resource is free and open to all users through http://sb.nhri.org.tw/ICES.

  3. Revival of the identification of cytotoxic T-lymphocyte epitopes for immunological diagnosis, therapy and vaccine development.

    PubMed

    Liu, Jun; Zhang, Shihong; Tan, Shuguang; Zheng, Beiwen; Gao, George F

    2011-03-01

    Immunogenic T-cell epitopes have a central role in the cellular immunity against pathogens and tumors. However, in the early stage of cellular immunity studies, it was complicated and time-consuming to identify and characterize T-cell epitopes. Currently, the epitope screening is experiencing renewed enthusiasm due to advances in novel techniques and theories. Moreover, the application of T-cell epitope-based diagnoses for tuberculosis and new data on epitope-based vaccine development have also revived the field. There is a growing knowledge on the emphasis of epitope-stimulated T-cell immune responses in the elimination of pathogens and tumors. In this review, we outline the significance of the identification and characterization of T-cell epitopes. We also summarize the methods and strategies for epitope definition and, more importantly, address the relevance of cytotoxic T-lymphocyte epitopes to clinical diagnoses, therapy and vaccine development.

  4. Identification of cytotoxic T lymphocyte epitopes in dengue virus serotype 1.

    PubMed

    Duan, Zhiliang; Guo, Jianglong; Huang, Xi; Liu, Huifang; Chen, Xinyu; Jiang, Minghua; Wen, Jinsheng

    2015-07-01

    Dengue virus (DENV) has a serious and growing impact on global health and the exact role of DENV-specific CD8(+) T-cells in DENV infection is still uncertain. In the present study, SYFPEITHI algorithm was used to screen the amino acid sequence of Dengue virus serotype 1 (DENV-1) for potential epitopes, and seven putative HLA-A*1101-restricted and five putative HLA-A*2402-restricted epitopes conserved in hundreds of DENV-1 strains were synthesized. The binding affinity of these epitope candidates to corresponding HLA molecules was evaluated using competitive peptide-binding assay. The immunogenicity and specificity of peptides were further tested in HLA-A*1101 transgenic mice, HLA-A*2402 transgenic mice and peripheral blood mononuclear cells (PBMCs) of patients infected with DENV-1. Percentage inhibition (PI) values calculated in competitive peptide-binding assay showed that six peptides (E39-47 PTLDIELLK, NS5(505-513) GVEGEGLHK, NS2b(15-23) SILLSSLLK, NS5(561-569) ALLATSIFK, NS3(99-107) AVEPGKNPK, and NS4b(159-167) VVYDAKFEK) could bind to HLA-A*1101 molecule with high affinity and five peptides (NS3472-480 QYIYMGQPL, NS4a40-48 AYRHAMEEL, NS5(880-888) DYMTSMKRF, NS3(548-556) SYKVASEGF, and NS3(22-30) IYRILQRGL) have a high affinity for HLA-A*2402 molecule. Enzyme-linked immunospot (ELISPOT) results indicated that these high-affinity peptides were recognized by splenocytes of DENV-1-infected transgenic mice and high-affinity peptide-immunized transgenic mice displayed high levels of peptide-specific IFN-γ-secreting cells. In addition, both peptide-pulsed splenocytes and DENV-1-infected splenic monocytes were efficiently killed by these peptide-specific cytotoxic T lymphocytes. Finally, except NS2b(15-23), 10 high-affinity peptides were recognized by PBMCs of patients infected with DENV-1. These identified epitopes would contribute to the understanding of the function of DENV-specific CD8(+) T-cells.

  5. HLA-A2-restricted cytotoxic T lymphocyte epitopes from human hepsin as novel targets for prostate cancer immunotherapy.

    PubMed

    Guo, J; Li, G; Tang, J; Cao, X-B; Zhou, Q-Y; Fan, Z-J; Zhu, B; Pan, X-H

    2013-09-01

    Hepsin is a type II transmembrane serine protease that is overexpressed in prostate cancer, and it is associated with prostate cancer cellular migration and invasion. Therefore, HPN is a biomarker for prostate cancer. CD8(+) T cells play an important role in tumour immunity. This study predicted and identified HLA-A2-restricted cytotoxic T lymphocyte (CTL) epitopes in human hepsin protein. HLA-A2-restricted CTL epitopes were identified using the following four-step procedure: (1) a computer program generated predicted epitopes from the amino acid sequence of human hepsin; (2) an HLA-A2-binding assay detected the affinity of the predicted epitopes to the HLA-A2 molecule; (3) the primary T cell response against the predicted epitopes was stimulated in vitro; and (4) the induced CTLs towards different types of hepsin- or HLA-A2-expressing prostate cancer cells were detected. Five candidate peptides were identified. The effectors that were induced by human hepsin epitopes containing residues 229 to 237 (Hpn229; GLQLGVQAV), 268 to 276 (Hpn268; PLTEYIQPV) and 191 to 199 (Hpn199; SLLSGDWVL) effectively lysed LNCaP prostate cancer cells that were hepsin-positive and HLA-A2 matched. These peptide-specific CTLs did not lyse normal liver cells with low hepsin levels. Hpn229, Hpn268 and Hpn199 increased the frequency of IFN-γ-producing T cells compared with the negative peptide. These results suggest that the Hpn229, Hpn268 and Hpn199 epitopes are novel HLA-A2-restricted CTL epitopes that are capable of inducing hepsin-specific CTLs in vitro. Hpn229, Hpn268 and Hpn199 peptide-based vaccines may be useful for immunotherapy in patients with prostate cancer.

  6. Hepatitis B surface antigen vector delivers protective cytotoxic T-lymphocyte responses to disease-relevant foreign epitopes.

    PubMed

    Woo, Wai-Ping; Doan, Tracy; Herd, Karen A; Netter, Hans-Jürgen; Tindle, Robert W

    2006-04-01

    Although hepatitis B surface antigen (HBsAg) per se is highly immunogenic, its use as a vector for the delivery of foreign cytotoxic T-lymphocyte (CTL) epitopes has met with little success because of constraints on HBsAg stability and secretion imposed by the insertion of foreign sequence into critical hydrophobic/amphipathic regions. Using a strategy entailing deletion of DNA encoding HBsAg-specific CTL epitopes and replacement with DNA encoding foreign CTL epitopes, we have derived chimeric HBsAg DNA immunogens which elicited effector and memory CTL responses in vitro, and pathogen- and tumor-protective responses in vivo, when the chimeric HBsAg DNAs were used to immunize mice. We further show that HBsAg DNA recombinant for both respiratory syncytial virus and human papillomavirus CTL epitopes elicited simultaneous responses to both pathogens. These data demonstrate the efficacy of HBsAg DNA as a vector for the delivery of disease-relevant protective CTL responses. They also suggest the applicability of the approach of deriving chimeric HBsAg DNA immunogens simultaneously encoding protective CTL epitopes for multiple diseases. The DNAs we tested formed chimeric HBsAg virus-like particles (VLPs). Thus, our results have implications for the development of vaccination strategies using either chimeric HBsAg DNA or VLP vaccines. HBsAg is the globally administered vaccine for hepatitis B virus infection, inviting its usage as a vector for the delivery of immunogens from other diseases.

  7. Identification of HLA-A*1101-restricted cytotoxic T lymphocyte epitopes derived from epidermal growth factor pathway substrate number 8

    PubMed Central

    Lu, Huifang; Tang, Baishan; He, Yanjie; Zhou, Weijun; Qiu, Jielei; Li, Yuhua

    2016-01-01

    Epidermal growth factor receptor pathway substrate 8 (EPS8) is critical in the proliferation, progression and metastasis of solid and hematological types of cancer, and thus constitutes an ideal target for cancer immunotherapy. The present study aimed to identify human leukocyte antigen (HLA)-A*1101-restricted cytotoxic T lymphocyte (CTL) epitopes from EPS8 and characterize their immunotherapeutic efficacy in vitro. Two computer-based algorithms were used to predict native EPS8 epitopes with potential high binding affinity to the HLA-A*1101 molecule, which is the HLA-A allele with the highest frequency in the Chinese population. The peptide-induced cytokine production from the CTLs was examined using enzyme-linked immunosorbent spot analysis. The cytotoxic effects on cancer cells by CTLs primed with the identified peptides were examined using flow cytometry. A total of five peptides, designated as P380, P70, P82, P30 and P529, presented with high affinity towards the HLA-A*1101 molecule. In response to stimulation by these five peptides, enhanced secretion of interferon-γ from the CTLs and increased cytolytic capabilities of the CTLs toward cancer cells were noted, with the most potent effects observed from the P380 peptide. Taken together, the present study identified five potential CTL epitopes from EPS8. Among these, P380 presented with the highest therapeutic efficacy in vitro. These peptides may benefit the development of EPS8-based immunotherapy for the treatment of HLA-A*1101-positive hematological malignancies. PMID:27840923

  8. HLA-A*0201 restricted CD8+ T-lymphocyte responses to malaria: identification of new Plasmodium falciparum epitopes by IFN-gamma ELISPOT.

    PubMed

    González, J M; Peter, K; Esposito, F; Nebié, I; Tiercy, J M; Bonelo, A; Arévalo-Herrera, M; Valmori, D; Romero, P; Herrera, S; Corradin, G; López, J A

    2000-10-01

    The role of antigen specific CD8+ T-lymphocytes in mediating protection against sporozoite-induced malaria has been well established in murine models. In humans, indirect evidence has accumulated suggesting a similar protective role for antigen-specific CD8+ T-lymphocytes. Nevertheless, the low frequency of circulating specific cells together with the lack of sensitive methods to quantify them has hampered the direct assessment of their function. Using a combination of short-term cell culture and IFN-gamma ELISPOT, we studied CD8+ T-lymphocyte responses to a panel of HLA-A*0201 binding peptides. In addition to confirming the response to already described epitopes, we also identified five new CD8+ T-lymphocyte epitopes. These epitopes are presented in pre-erythrocytic stages gene products of Plasmodium falciparum 7G8 strain and correspond to the following protein segments: circumsporozoite (CS) 64-72, 104-113, 299-308 and 403-411; liver stage antigen (LSA-1) repeat region; sporozoite surface protein 2 or thrombospondin related anonymous protein (SSP2/TRAP) 78-88 and 504-513. Four of these peptides are conserved amongst all published sequences of P. falciparum strains. We conclude that the modified IFN-gamma ELISPOT assay is a sensitive technique to monitor antigen-specific CD8+ T-lymphocyte responses in human malaria which may help in the improvement and assessment of the efficacy of malaria subunit vaccines.

  9. Identification of HLA-A*0201-restricted cytotoxic T lymphocyte epitope from proliferating cell nuclear antigen.

    PubMed

    Xu, Wei; Li, Hui-Zhong; Liu, Jun-Jie; Guo, Zhen; Zhang, Bao-Fu; Chen, Fei-Fei; Pei, Dong-Sheng; Zheng, Jun-Nian

    2011-02-01

    Peptide-based immunotherapy strategies appear promising as an approach to successfully induce an antitumor immune response and prolong survival in patients with various cancers. Protein antigens and their specific epitopes are formulation targets for anti-tumor vaccines. Bioinformatical approaches to predict major histocompatibility complex binding peptides can facilitate the resource-consuming effort of T cell epitope identification. Proliferating cell nuclear antigen including Ki-67 and PCNA, associated with the proliferation process of the cell, seems to be an attractive new target for tumor-specific immunotherapy. In this study, we predicted seven HLA-A*0201-restricted CTL candidate epitope of Ki-67 and eight epitope of PCNA by computer algorithm SYFPEITHI, BIMAS, and IEDB_ANN. Subsequently, biological functions of these peptides were tested by experiments in vitro. We found Ki-67((280-288)) (LQGETQLLV) had the strongest binding-affinity with HLA-A*0201. Further study revealed that Ki-67((280-288)) increased the frequency of IFN-γ-producing T cells compared to a negative peptide. Because Ki-67 was broadly expressed in most advanced malignant tumors, indicating a potential anti-tumor application in the future.

  10. Prediction and identification of mouse cytotoxic T lymphocyte epitopes in Ebola virus glycoproteins

    PubMed Central

    2012-01-01

    Background Ebola viruses (EBOVs) cause severe hemorrhagic fever with a high mortality rate. At present, there are no licensed vaccines or efficient therapies to combat EBOV infection. Previous studies have shown that both humoral and cellular immune responses are crucial for controlling Ebola infection. CD8+ T cells play an important role in mediating vaccine-induced protective immunity. The objective of this study was to identify H-2d-specific T cell epitopes in EBOV glycoproteins (GPs). Results Computer-assisted algorithms were used to predict H-2d-specific T cell epitopes in two species of EBOV (Sudan and Zaire) GP. The predicted peptides were synthesized and identified in BALB/c mice immunized with replication-deficient adenovirus vectors expressing the EBOV GP. Enzyme-linked immunospot assays and intracellular cytokine staining showed that the peptides RPHTPQFLF (Sudan EBOV), GPCAGDFAF and LYDRLASTV (Zaire EBOV) could stimulate splenoctyes in immunized mice to produce large amounts of interferon-gamma. Conclusion Three peptides within the GPs of two EBOV strains were identified as T cell epitopes. The identification of these epitopes should facilitate the evaluation of vaccines based on the Ebola virus glycoprotein in a BALB/c mouse model. PMID:22695180

  11. Epitopes recognized by human T lymphocytes in the ROP2 protein antigen of Toxoplasma gondii.

    PubMed Central

    Saavedra, R; Becerril, M A; Dubeaux, C; Lippens, R; De Vos, M J; Hérion, P; Bollen, A

    1996-01-01

    The ROP2 protein of Toxoplasma gondii possesses immunological and biological properties which have led to its proposal as a vaccine candidate. To identify epitopes recognized by human T cells in the ROP2 antigen, we submitted the sequence of this protein to three reported T-cell epitope prediction algorithms. Three sequences that were predicted by all three methods were selected (sequences 197 to 216, 393 to 410, and 501 to 524), and the corresponding peptides were synthesized. The peptides were first tested in a proliferation assay with a DPw4-restricted, ROP2-specific human T-cell clone, and the peptide corresponding to residues 197 to 216 was shown to stimulate the T-cell clone. The three peptides were further tested in proliferation assays with peripheral blood mononuclear cells from a panel of T. gondii-seropositive and -seronegative individuals. We found that cells from a high proportion of the seropositive donors (64%) recognized at least one of the three peptides. The most frequently recognized ones were peptides 197 to 216 (45%) and 501 to 524 (36%). None of the seronegative donors responded to any peptide. These results show that the ROP2 antigen of T. gondii contains T-cell epitopes recognized by a high percentage of the immune population and further strengthen its potential as a vaccine candidate. PMID:8751939

  12. A specific cytotoxic T-lymphocyte epitope presentation system for antitumor immunity.

    PubMed

    Wu, Ying; Liu, Changzhen; Sun, Meiyi; Shen, Hexiao; Guo, Deyin; Gao, Bin

    2010-05-15

    The magnitude of CTL-mediated immunity response is highly dependent on the density of antigenic peptide-MHC I complexes at the cell surface. In this study, we adopt a novel strategy to promote the surface level of specific peptide-MHC I complexes. The strategy combines the inhibition of transporter associated with antigen processing (TAP) with the delivery of specific peptide into endoplasmic reticulum directly without the help of TAP. First, RNA interference (RNAi) technology was used to inhibit TAP expression for blocking endogenous epitope-assembled MHC class I on cell surface. Second, a peptide epitope of interest was covalently linked onto human beta-2-microglobulin (beta2m). Both TAP-specific siRNA and the peptide-linked beta2m were delivered into antigen-presentation cells sequentially or simultaneously using a retrovirus delivery system. The combined strategy produces a significant amount of MHC I loaded with specific epitopes on the surface while reducing endogenously peptide-assembled MHC class I both in vitro and in vivo. The efficacy of induction of specific immune response with the strategy against tumor cells is demonstrated in both tumor cell lines and a syngenic graft tumor model.

  13. Cytotoxic T lymphocytes recognize an HLA-A2-restricted epitope within the hepatitis B virus nucleocapsid antigen

    PubMed Central

    1991-01-01

    The absence of readily manipulable experimental systems to study the cytotoxic T lymphocyte (CTL) response against hepatitis B virus (HBV) antigens has thus far precluded a definitive demonstration of the role played by this response in the pathogenesis of liver cell injury and viral clearance during HBV infection. To circumvent the problem that HBV infection of human cells in vitro for production of stimulator/target systems for CTL analysis is not feasible, a panel of 22 overlapping synthetic peptides covering the entire amino acid sequence of the HBV core (HBcAg) and e (HBeAg) antigens were used to induce and to analyze the HBV nucleocapsid-specific CTL response in nine patients with acute hepatitis B, six patients with chronic active hepatitis B, and eight normal controls. By using this approach, we have identified an HLA-A2-restricted CTL epitope, located within the NH2- terminal region of the HBV core molecule, which is shared with the e antigen and is readily recognized by peripheral blood mononuclear cells from patients with self-limited acute hepatitis B but less efficiently in chronic HBV infection. Our study provides the first direct evidence of HLA class I-restricted T cell cytotoxicity against HBV in humans. Furthermore, the different response in HBV-infected subjects who successfully clear the virus (acute patients) in comparison with patients who do not succeed (chronic patients) suggests a pathogenetic role for this CTL activity in the clearance of HBV infection. PMID:1720813

  14. Shifting immunodominance pattern of two cytotoxic T-lymphocyte epitopes in the F glycoprotein of the Long strain of respiratory syncytial virus.

    PubMed

    Johnstone, Carolina; de León, Patricia; Medina, Francisco; Melero, José A; García-Barreno, Blanca; Del Val, Margarita

    2004-11-01

    Human respiratory syncytial virus (RSV) is a major cause of respiratory infection in children and in the elderly. The RSV fusion (F) glycoprotein has long been recognized as a vaccine candidate as it elicits cytotoxic T-lymphocyte (CTL) and antibody responses. Two murine H-2K(d)-restricted CTL epitopes (F85-93 and F92-106) are known in the F protein of the A2 strain of RSV. F-specific CTL lines using BCH4 fibroblasts that are persistently infected with the Long strain of human RSV as stimulators were generated, and it was found that in this strain only the F85-93 epitope is conserved. Motif based epitope prediction programs and an F2 chain deleted F protein encoded in a recombinant vaccinia virus enabled identification of a new epitope in the Long strain, F249-258, which is presented by K(d) as a 9-mer (TYMLTNSEL) or a 10-mer (TYMLTNSELL) peptide. The results suggest that the 10-mer might be a naturally processed endogenous K(d) ligand. The CD8(+) T-lymphocyte responses to epitopes F85-93 and F249-258 present in the F protein of RSV Long were found to be strongly skewed to F85-93 in in vitro multispecific CTL lines and in vivo during a secondary response to a recombinant vaccinia virus that expresses the entire F protein. However, no hierarchy in CD8(+) T-lymphocyte responses to F85-93 and F249-258 epitopes was observed in vivo during a primary response.

  15. Flavivirus-cross-reactive, HLA-DR15-restricted epitope on NS3 recognized by human CD4+ CD8- cytotoxic T lymphocyte clones.

    PubMed

    Kurane, I; Okamoto, Y; Dai, L C; Zeng, L L; Brinton, M A; Ennis, F A

    1995-09-01

    The role of flavivirus-cross-reactive T lymphocytes in recovery from and pathogenesis of flavivirus infections is not known. In the present paper, we have defined a flavivirus-cross-reactive epitope recognized by two CD4+ CD8- cytotoxic T lymphocyte (CTL) clones, JK4 and JK43. The T cell clones were established from the peripheral blood T lymphocytes of a dengue-4-immune donor, using a limiting-dilution method with dengue-4 antigen. These two T cell clones were cross-reactive for dengue virus types 1, 2, 3 and 4, yellow fever virus and West Nile virus, and recognized NS3 protein. The smallest synthetic peptide recognized by these T cell clones was an identical 9 amino acid peptide which contains amino acids 146 to 154 (VIGLYGNGV) of dengue-4 NS3. HLA-DR15 was the restriction allele for recognition of this epitope by JK4 and JK43. JK4 and JK43 both used T cell receptor V alpha 8, but JK4 used V beta 8 and JK43 used V beta 2. This result indicates that this epitope is recognized by two flavivirus-cross-reactive CD4+ T cell clones which originated from different T cells in vivo.

  16. Human Memory Cytotoxic T-Lymphocyte (CTL) Responses to Hantaan Virus Infection: Identification of Virus-Specific and Cross-Reactive CD8+ CTL Epitopes on Nucleocapsid Protein

    PubMed Central

    Van Epps, Heather L.; Schmaljohn, Connie S.; Ennis, Francis A.

    1999-01-01

    Hantaan virus, the prototypic member of the Hantavirus genus, causes hemorrhagic fever with renal syndrome in humans. We examined the human memory T-lymphocyte responses of three donors who had previous laboratory-acquired infections with Hantaan virus. We demonstrated virus-specific responses in bulk cultures of peripheral blood mononuclear cells (PBMC) from all donors. Bulk T-cell responses were directed against either Hantaan virus nucleocapsid (N) or G1 protein, and these responses varied between donors. We established both CD4+ and CD8+ N-specific cell lines from two donors and CD4+ G1-specific cell lines from a third donor. All CD8+ cytotoxic T-lymphocyte (CTL) lines recognized one of two epitopes on the nucleocapsid protein: one epitope spanning amino acids 12 to 20 and the other spanning amino acids 421 to 429. The CTL lines specific for amino acids 12 to 20 were restricted by HLA B51, and those specific for amino acids 421 to 429 were restricted by HLA A1. The N-specific CTL lines isolated from these two donors included both Hantaan virus-specific CTLs and hantavirus cross-reactive CTLs. Responses to both epitopes are detectable in short-term bulk cultures of PBMC from one donor, and precursor frequency analysis confirms that CTLs specific for these epitopes are present at relatively high precursor frequencies in the peripheral T-cell pool. These data suggest that infection with Hantaan virus results in the generation of CTL to limited epitopes on the nucleocapsid protein and that infection also results in the generation of cross-reactive T-cell responses to distantly related hantaviruses which cause the distinct hantavirus pulmonary syndrome. This is the first demonstration of human T-lymphocyte responses to Hantaan virus. PMID:10364276

  17. Definition of an epitope on NS3 recognized by human CD4+ cytotoxic T lymphocyte clones cross-reactive for dengue virus types 2, 3, and 4.

    PubMed

    Kurane, I; Zeng, L; Brinton, M A; Ennis, F A

    1998-01-20

    The role of dengue virus-specific serotype-cross-reactive T lymphocytes in recovery from and pathogenesis of dengue virus infections is not known. In the present paper, we have defined a dengue serotype-cross-reactive epitope recognized by two CD4+ CD8- cytotoxic T lymphocyte (CTL) clones, JK36 and JK46. These T cell clones were established from the peripheral blood T lymphocytes of a dengue-3-immune donor, using a limiting dilution method. JK36 and JK46 were cross-reactive for dengue virus types 2, 3, and 4, but not for type 1, and recognized the NS3 protein. The smallest synthetic peptide recognized by JK36 was an 8-amino acid peptide that contains amino acids (aa) 226 to 233 (VVAAEMEE) of NS3. The smallest peptide recognized by JK46 was an 11-amino acid peptide that contains aa 224 to 234 (TRVVAAEMEEA). HLA-DR15 was the restriction allele for recognition of these peptides by both JK36 and JK46. This is the first epitope to be defined that is recognized by human CD4+ CTL cross-reactive for dengue virus types 2, 3, and 4.

  18. Cytotoxic T lymphocyte response to a wild type hepatitis B virus epitope in patients chronically infected by variant viruses carrying substitutions within the epitope

    PubMed Central

    1994-01-01

    Mutations that abrogate recognition of a viral epitope by class I- restricted cytotoxic T lymphocyte (CTL) can lead to viral escape if the CTL response against that epitope is crucial for viral clearance. The likelihood of this type of event is low when the CTL response is simultaneously directed against multiple viral epitopes, as has been recently reported for patients with acute self-limited hepatitis B virus (HBV) infection. The CTL response to HBV is usually quite weak, however, during chronic HBV infection, and it is generally acknowledged that this is a major determinant of viral persistence in this disease. If such individuals were to produce a mono- or oligospecific CTL response, however, negative selection of the corresponding mutant viruses might occur. We have recently studied two HLA-A2-positive patients with chronic hepatitis B who, atypically, developed a strong HLA-A2-restricted CTL response against an epitope (FLPSDFFPSV) that contains an HLA-A2-binding motif located between residues 18-27 of the viral nucleocapsid protein, hepatitis B core antigen (HBcAg). These patients failed, however, to respond to any of other HLA-A2-restricted HBV-derived peptides that are generally immunogenic in acutely infected patients who successfully clear the virus. Interestingly, DNA sequence analysis of HBV isolates from these two patients demonstrated alternative residues at position 27 (V --> A and V --> I) and position 21 (S --> N, S --> A, and S --> V) that reduced the HLA and T cell receptor-binding capacities of the variant sequences, respectively. Synthetic peptides containing these alternative sequences were poorly immunogenic compared to the prototype HBc18-27 sequence, and they could not be recognized by CTL clones specific for the prototype peptide. While we do not know if the two patients were originally infected by these variant viruses or if the variants emerged subsequent to infection because of immune selection, the results are most consistent with

  19. Alphavirus-Specific Cytotoxic T Lymphocytes Recognize a Cross-Reactive Epitope from the Capsid Protein and Can Eliminate Virus from Persistently Infected Macrophages

    PubMed Central

    Linn, May La; Mateo, L.; Gardner, J.; Suhrbier, A.

    1998-01-01

    Persistent alphavirus infections in synovial and neural tissues are believed to be associated with chronic arthritis and encephalitis, respectively, and represent likely targets for CD8+ αβ cytotoxic T lymphocytes (CTL). Here we show that the capsid protein is a dominant target for alphavirus-specific CTL in BALB/c mice and that capsid-specific CTL from these mice recognize an H-2Kd restricted epitope, QYSGGRFTI. This epitope lies in the highly conserved region of the capsid protein, and QYSGGRFTI-specific CTL were cross reactive across a range of Old World alphaviruses. In vivo the acute primary viraemia of these highly cytopathic viruses was unaffected by QYSGGRFTI-specific CTL. However, in vitro these CTL were able to completely clear virus from macrophages persistently and productively infected with the arthrogenic alphavirus Ross River virus. PMID:9573286

  20. Cytolytic T lymphocytes (CTLs) from HIV-1 subtype C-infected Indian patients recognize CTL epitopes from a conserved immunodominant region of HIV-1 Gag and Nef.

    PubMed

    Thakar, Madhuri R; Bhonge, Leena S; Lakhashe, Samir K; Shankarkumar, U; Sane, Suvarna S; Kulkarni, Smita S; Mahajan, Bharati A; Paranjape, Ramesh S

    2005-09-01

    Analysis of the human immunodeficiency virus type 1 (HIV-1) cytolytic T lymphocyte (CTL) epitopes recognized by the targeted population is critical for HIV-1 vaccine design. Peripheral blood mononuclear cells from 47 Indian subjects at different stages of HIV-1 infection were tested for HIV-1 Gag-, Nef-, and Env-specific T cell responses by interferon (IFN)- gamma enzyme-linked immunospot (ELISPOT) assay, using pools of overlapping peptides. The Gag and Nef antigens were targeted by 83% and 36% of responders. Five immunodominant regions, 4 in Gag and 1 in Nef, were identified in the study; these regions are conserved across clades, including the African subtype C clade. Three antigenic regions were also found to be recognized by CTLs of the study participants. These regions were not identified as immunodominant regions in studies performed in Africa, which highlights the importance of differential clustering of responses within HIV-1 subtype C. Twenty-six putative epitopes--15 Gag (10 in p24 and 5 in p17), 10 Nef, and 1 Env (gp 41)--were predicted using a combination of peptide matrix ELISPOT assay and CTL epitope-prediction software. Ninety percent of the predicted epitopes were clustered in the conserved immunodominant regions of the Gag and Nef antigens. Of 26 predicted epitopes, 8 were promiscuous, 3 of which were highly conserved across clades. Three Gag and 4 Nef epitopes were novel. The identification of conserved epitopes will be important in the planning of an HIV-1 vaccine strategy for subtype C-affected regions.

  1. Identification of CD8+ cytotoxic T lymphocyte epitopes from porcine reproductive and respiratory syndrome virus matrix protein in BALB/c mice

    PubMed Central

    2011-01-01

    Twenty-seven nanopeptides derived from the matrix (M) protein of porcine reproductive and respiratory syndrome virus (PRRSV) were screened for their ability to elicit a recall interferon-γ (IFN-γ) response from the splenocytes of BALB/c mice following DNA vaccination and a booster vaccination with recombinant vaccinia virus rWR-PRRSV-M. We identified two peptides (amino acid residues K93FITSRCRL and F57GYMTFVHF) as CD8+ cytotoxic T lymphocyte (CTL) epitopes. These peptides elicited significant numbers of IFN-γ secreting cells, compared with other M nonapeptides and one irrelevant nonapeptide. Bioinformatics analysis showed that the former is an H-2Kd-restricted CTL epitope, and the latter is an H-2Dd-restricted CTL epitope. Multiple amino acid sequence alignment among different PRRSV M sequences submitted to GenBank indicated that these two CTL epitopes are strongly conserved, and they should therefore be considered for further research on the mechanisms of cellular immune responses to PRRSV. PMID:21619712

  2. A vaccine-elicited, single viral epitope-specific cytotoxic T lymphocyte response does not protect against intravenous, cell-free simian immunodeficiency virus challenge.

    PubMed Central

    Yasutomi, Y; Koenig, S; Woods, R M; Madsen, J; Wassef, N M; Alving, C R; Klein, H J; Nolan, T E; Boots, L J; Kessler, J A

    1995-01-01

    Protection against simian immunodeficiency virus (SIV) challenge was assessed in rhesus monkeys with a vaccine-elicited, single SIV epitope-specific cytotoxic T-lymphocyte (CTL) response in the absence of SIV-specific antibody. Strategies were first explored for eliciting an optimal SIV Gag epitope-specific CTL response. These studies were performed in rhesus monkeys expressing the major histocompatibility complex (MHC) class I gene Mamu-A*01, a haplotype associated with a predominant SIV CTL epitope mapped to residues 182 to 190 of the Gag protein (p11C). We demonstrated that a combined modality immunization strategy using a recombinant Mycobacterium bovis BCG-SIV Gag construct for priming, and peptide formulated in liposome for boosting, elicited a greater p11C-specific CTL response than did a single immunization with peptide-liposome alone. Vaccinated and control monkeys were then challenged with cell-free SIVmne by an intravenous route of inoculation. Despite a vigorous p11C-specific CTL response at the time of virus inoculation, all monkeys became infected with SIV. gag gene sequencing of the virus isolated from these monkeys demonstrated that the established viruses had no mutations in the p11C-coding region. Thus, the preexisting CTL response did not select for a viral variant that might escape T-cell immune recognition. These studies demonstrate that a potent SIV-specific CTL response can be elicited by combining live vector and peptide vaccine modalities. However, a single SIV Gag epitope-specific CTL response in the absence of SIV-specific antibody did not provide protection against a cell-free, intravenous SIV challenge. PMID:7884874

  3. A Novel CD8-Independent High-Avidity Cytotoxic T-Lymphocyte Response Directed against an Epitope in the Phosphoprotein of the Paramyxovirus Simian Virus 5

    PubMed Central

    Gray, Peter M.; Parks, Griffith D.; Alexander-Miller, Martha A.

    2001-01-01

    Adoptive transfer studies have shown that cytotoxic T lymphocytes (CTL) of high avidity, capable of recognizing low levels of peptide-MHC I molecules, are more efficient at reducing viral titers than are low-avidity CTL, thus establishing CTL avidity as a critical parameter for the ability of a CTL to clear virus in vivo. It has been well documented that CTL of high avidity are relatively CD8 independent, whereas low-avidity CTL require CD8 engagement in order to become activated. In this study we have analyzed the antiviral CTL response elicited following infection with the paramyxovirus simian virus 5 (SV5). We have identified the immunodominant and subdominant CTL responses and subsequently assessed the avidity of these responses by their CD8 dependence. This is the first study in which the relationship between immunodominance and CTL avidity has been investigated. The immunodominant response was directed against an epitope present in the viral M protein, and subdominant responses were directed against epitopes present in the P, F, and HN proteins. Similarly to other CTL responses we have analyzed, the immunodominant response and the subdominant F and HN responses were comprised of both high- and low-avidity CTL. However, the subdominant response directed against the epitope present in the P protein is novel, as it is exclusively high avidity. This high-avidity response is independent of both the route of infection and expression by recombinant SV5. A further understanding of the inherent properties of P that elicit only high-avidity CTL may allow for the design of more efficacious vaccine vectors that preferentially elicit high-avidity CTL in vivo. PMID:11581375

  4. Identification of Immunogenic Cytotoxic T Lymphocyte Epitopes Containing Drug Resistance Mutations in Antiretroviral Treatment-Naïve HIV-Infected Individuals

    PubMed Central

    Blanco-Heredia, Juan; Lecanda, Aarón; Valenzuela-Ponce, Humberto; Brander, Christian; Ávila-Ríos, Santiago; Reyes-Terán, Gustavo

    2016-01-01

    Background Therapeutic HIV vaccines may prove helpful to intensify antiretroviral treatment (ART) efficacy and may be an integral part of future cure strategies. Methods We examined IFN-gamma ELISpot responses to a panel of 218 HIV clade B consensus-based HIV protease-reverse transcriptase peptides, designed to mimic previously described and predicted cytotoxic T lymphocyte epitopes overlapping drug resistance (DR) positions, that either included the consensus sequence or the DR variant sequence, in 49 ART-naïve HIV-infected individuals. Next generation sequencing was used to assess the presence of minority DR variants in circulating viral populations. Results Although a wide spectrum of differential magnitudes of response to DR vs. WT peptide pairs was observed, responses to DR peptides were frequent and strong in the study cohort. No difference between the median magnitudes of response to DR vs. WT peptides was observed. Interestingly, of the 22 peptides that were recognized by >15% of the participants, two-thirds (64%) corresponded to DR peptides. When analysing responses per peptide pair per individual, responses to only WT (median 4 pairs/individual) or DR (median 6 pairs/individual) were more common than responses to both WT and DR (median 2 pairs/individual; p<0.001). While the presence of ELISpot responses to WT peptides was frequently associated with the presence of the corresponding peptide sequence in the patient’s virus (mean 68% of cases), responses to DR peptides were generally not associated with the presence of DR mutations in the viral population, even at low frequencies (mean 1.4% of cases; p = 0.0002). Conclusions Our data suggests that DR peptides are frequently immunogenic and raises the potential benefit of broadening the antigens included in a therapeutic vaccine approach to immunogenic epitopes containing common DR sequences. Further studies are needed to assess the quality of responses elicited by DR peptides. PMID:26808823

  5. Functional profile of human influenza virus-specific cytotoxic T lymphocyte activity is influenced by interleukin-2 concentration and epitope specificity

    PubMed Central

    Boon, ACM; de Mutsert, G; Fouchier, RAM; Osterhaus, ADME; Rimmelzwaan, GF

    2005-01-01

    The ability of influenza A virus-specific cytotoxic T lymphocytes (CTL) to degranulate and produce cytokines upon antigenic restimulation was studied in four HLA-A*0101 and HLA-A*0201 positive subjects. Peripheral blood mononuclear cells of these subjects were stimulated with influenza A virus in the presence of high or low interleukin (IL)-2 concentrations. CD8+ T cell populations specific for the HLA-A*0101 restricted epitope NP44–52 and the HLA-A*0201 restricted epitope M158–66 were identified by positive staining with tetramers of peptide major histocompatibility complexes (MHC) (NP-Tm and M1-Tm, respectively). Within these populations, the proportion of cells mobilizing CD107a, or expressing interferon (IFN)-γ and tumour necrosis factor-(TNF)-α upon short-term peptide restimulation was determined by flow cytometry. Independent of IL-2 concentrations, large subject-dependent differences in the mobilization of CD107a and expression of IFN-γ and TNF-α by both NP- and M1-specific T cells were observed. In two of the four subjects, the functional profile of NP-Tm+ and M1-Tm+ cells differed considerably. Overall, no difference in the proportion of NP-Tm+ or M1-Tm+ cells expressing CD107a was observed. The proportion of M1-Tm+ cells that produced IFN-γ (P < 0·05) was larger than for NP-Tm+ cells, independent of IL-2 concentration. When cultured under IL-2hi concentrations higher TNF-α expression was also observed in M1-Tm+ cells (P < 0·05). The IL-2 concentration during expansion of virus-specific cells had a profound effect on the functionality of both M1-Tm+ and NP-Tm+ cells. PMID:16178855

  6. Effect of mutations and variations of HLA-A2 on recognition of a virus peptide epitope by cytotoxic T lymphocytes.

    PubMed Central

    McMichael, A J; Gotch, F M; Santos-Aguado, J; Strominger, J L

    1988-01-01

    Cytotoxic T lymphocytes (CTL) specific for influenza A virus were prepared from 15 donors. Those with HLA-A2 recognized autologous or HLA-A2-matched B-lymphoblastoid cells in the presence of synthetic peptide representing residues 55-73 or 56-68 of the virus matrix protein sequence. Influenza A virus-specific CTL from donors without HLA-A2 or with an HLA-A2 variant type failed to respond to this peptide. CTL lines specific for HLA-A2 plus peptide did not lyse peptide-treated target cells from HLA-A2 variant donors. They also failed to lyse peptide-treated cells with point mutations that had been inserted into HLA-A2 at positions 62-63, 66, 152, and 156 and, in some instances, mutations at positions 9 and 70. CTL lysed peptide-treated target cells with mutations in HLA-A2 at positions 43, 74, and 107. The results imply that this defined peptide epitope therefore interacts with HLA-A2 in the binding groove so that the long alpha-helices of HLA-A2 make important contact with the peptide at positions 66, 152, and 156. Different amino acids at position 9, which is in the floor of the peptide binding groove of HLA-A2 and the closely related position 70, modulate the peptide interaction so that some T-cell clones react and some do not. PMID:2461564

  7. Generation of T-cell receptors targeting a genetically stable and immunodominant cytotoxic T-lymphocyte epitope within hepatitis C virus non-structural protein 3.

    PubMed

    Pasetto, Anna; Frelin, Lars; Brass, Anette; Yasmeen, Anila; Koh, Sarene; Lohmann, Volker; Bartenschlager, Ralf; Magalhaes, Isabelle; Maeurer, Markus; Sällberg, Matti; Chen, Margaret

    2012-02-01

    Hepatitis C virus (HCV) is a major cause of severe liver disease, and one major contributing factor is thought to involve a dysfunction of virus-specific T-cells. T-cell receptor (TCR) gene therapy with HCV-specific TCRs would increase the number of effector T-cells to promote virus clearance. We therefore took advantage of HLA-A2 transgenic mice to generate multiple TCR candidates against HCV using DNA vaccination followed by generation of stable T-cell-BW (T-BW) tumour hybrid cells. Using this approach, large numbers of non-structural protein 3 (NS3)-specific functional T-BW hybrids can be generated efficiently. These predominantly target the genetically stable HCV genotype 1 NS3(1073-1081) CTL epitope, frequently associated with clearance of HCV in humans. These T-BW hybrid clones recognized the NS3(1073) peptide with a high avidity. The hybridoma effectively recognized virus variants and targeted cells with low HLA-A2 expression, which has not been reported previously. Importantly, high-avidity murine TCRs effectively redirected human non-HCV-specific T-lymphocytes to recognize human hepatoma cells with HCV RNA replication driven by a subgenomic HCV replicon. Taken together, TCR candidates with a range of functional avidities, which can be used to study immune recognition of HCV-positive targets, have been generated. This has implications for TCR-related immunotherapy against HCV.

  8. Oral vaccination with attenuated Salmonella enterica strains encoding T-cell epitopes from tumor antigen NY-ESO-1 induces specific cytotoxic T-lymphocyte responses.

    PubMed

    Meng, Jia-Zi; Dong, Yu-Jun; Huang, He; Li, Shuang; Zhong, Yi; Liu, Shu-Lin; Wang, Yue-Dan

    2010-06-01

    Bacterial fimbriae can accept foreign peptides and display them on the cell surface. A highly efficient gene replacement method was used to generate peptide vaccines based on Salmonella enterica serovar Typhimurium SL3261. The T-cell epitopes (NY-ESO-1 p157-165 and p157-167) from NY-ESO-1, which is a promising target antigen in patients for the specific immune recognition of cancer, were incorporated into the gene encoding AgfA (the major subunit protein of thin aggregative fimbriae of Salmonella) by replacing an equal length of the DNA segment. To improve cytotoxic T-lymphocyte recognition, both termini of the peptide were flanked by double alanine (AA) residues. Immunofluorescence microscopy with AgfA-specific antiserum verified the expression of chimeric AgfA, which was also proved by a Congo red binding assay. Oral immunizations of HLA-A*0201 transgenic mice with recombinant SL3261 strains encoding NY-ESO-1 p157-165 or p157-167 induced NY-ESO-1 p157-165-specific CD8(+) T cells, detected by an HLA-A*0201 pentamer, and induced a T-cell response detected by an enzyme-linked immunospot assay. The Salmonella fimbrial display system was efficient at the induction of an antitumor cellular immune response in vivo, providing a new strategy for the development of efficient cancer vaccinations.

  9. A novel approach to the identification of T-cell epitopes in Mycobacterium tuberculosis using human T-lymphocyte clones.

    PubMed Central

    Lamb, J R; Young, D B

    1987-01-01

    Current approaches to the analysis of antigens involved in the cellular immune response to mycobacterial infection rely on the initial identification and isolation of molecular components using monoclonal antibodies. In order to overcome the constraints of this approach, we have utilized a procedure involving T-cell recognition of antigens fractionated by polyacrylamide gel electrophoresis (SDS-PAGE) and added to proliferation assays after blotting onto nitrocellulose membranes. Analysis of human T-cell responses to Mycobacterium tuberculosis and Mycobacterium bovis BCG by this procedure revealed distinctive patterns of reactivity to different molecular weight components indicative of the selective recognition of immunodominant and species-specific determinants. Human T-cell clones were subsequently derived, and SDS-PAGE immunoblotting was used to identify the antigen recognized by each clone. Three epitopes defined by individual T-cell clones were identified on separate polypeptides with molecular weights 16,000-18,000 (clone P53), 18,000-20,000 (clone P57) and 52,000-55,000 (clone P35). This study demonstrates the potential application of T-cell cloning in conjunction with SDS-PAGE immunoblotting for the dissection and analysis of the cellular immune response to pathogenic agents during human infection. Images Figure 1 PMID:2434413

  10. Patterns of Immunodominance in HIV-1–specific Cytotoxic T Lymphocyte Responses in Two Human Histocompatibility Leukocyte Antigens (HLA)-identical Siblings with HLA-A*0201 Are Influenced by Epitope Mutation

    PubMed Central

    Goulder, P.J.R.; Sewell, A.K.; Lalloo, D.G.; Price, D.A.; Whelan, J.A.; Evans, J.; Taylor, G.P.; Luzzi, G.; Giangrande, P.; Phillips, R.E.; McMichael, A.J.

    1997-01-01

    Primary human immunodeficiency virus (HIV) infection is controlled principally by HIV-specific cytotoxic T lymphocytes (CTL) to a steady-state level of virus load, which strongly influences the ultimate rate of progression to disease. Epitope selection by CTL may be an important determinant of the degree of immune control over the virus. This report describes the CTL responses of two HLA-identical hemophiliac brothers who were exposed to identical batches of Factor VIII and became seropositive within 10 wk of one another. Both have HLA-A*0201. The CTL responses of the two siblings were very dissimilar, one donor making strong responses to two epitopes within p17 Gag (HLA-A*0201–restricted SLYNTVATL and HLA-A3–restricted RLRPGGKKK). The sibling responded to neither epitope, but made strong responses to two epitopes presented by HLA-B7. This was not the result of differences in presentation of the epitopes. However, mutations in both immunodominant epitopes of the p17 Gag responder were seen in proviral sequences of the nonresponder. We then documented the CTL responses to two HLA-A*0201–restricted epitopes, in Gag (SLYNTVATL) and Pol (ILKEPVHGV) in 22 other HIV-infected donors with HLA-A*0201. The majority (71%) generated responses to the Gag epitope. In the 29% of donors failing to respond to the Gag epitope in standard assays, there was evidence of low frequency memory CTL responses using peptide stimulation of PBMC, and most of these donors also showed mutations in or around the Gag epitope. We concluded that HLA class I genotype determines epitope selection initially but that mutation in immunodominant epitopes can profoundly alter the pattern of CTL response. PMID:9126923

  11. Identification of Two New HLA-A*1101-Restricted Tax Epitopes Recognized by Cytotoxic T Lymphocytes in an Adult T-Cell Leukemia Patient after Hematopoietic Stem Cell Transplantation

    PubMed Central

    Harashima, Nanae; Tanosaki, Ryuji; Shimizu, Yukiko; Kurihara, Kiyoshi; Masuda, Takao; Okamura, Jun; Kannagi, Mari

    2005-01-01

    We previously reported that Tax-specific CD8+ cytotoxic T lymphocytes (CTLs), directed to single epitopes restricted by HLA-A2 or A24, expanded in vitro and in vivo in peripheral blood mononuclear cells (PBMC) from some adult T-cell leukemia (ATL) patients after but not before allogeneic hematopoietic stem cell transplantation (HSCT). Here, we demonstrated similar Tax-specific CTL expansion in PBMC from another post-HSCT ATL patient without HLA-A2 or A24, whose CTLs equally recognized two newly identified epitopes, Tax88-96 and Tax272-280, restricted by HLA-A11, suggesting that these immunodominant Tax epitopes are present in the ATL patient in vivo. PMID:16014972

  12. Identification of two new HLA-A*1101-restricted tax epitopes recognized by cytotoxic T lymphocytes in an adult T-cell leukemia patient after hematopoietic stem cell transplantation.

    PubMed

    Harashima, Nanae; Tanosaki, Ryuji; Shimizu, Yukiko; Kurihara, Kiyoshi; Masuda, Takao; Okamura, Jun; Kannagi, Mari

    2005-08-01

    We previously reported that Tax-specific CD8(+) cytotoxic T lymphocytes (CTLs), directed to single epitopes restricted by HLA-A2 or A24, expanded in vitro and in vivo in peripheral blood mononuclear cells (PBMC) from some adult T-cell leukemia (ATL) patients after but not before allogeneic hematopoietic stem cell transplantation (HSCT). Here, we demonstrated similar Tax-specific CTL expansion in PBMC from another post-HSCT ATL patient without HLA-A2 or A24, whose CTLs equally recognized two newly identified epitopes, Tax88-96 and Tax272-280, restricted by HLA-A11, suggesting that these immunodominant Tax epitopes are present in the ATL patient in vivo.

  13. Crystal structure of swine major histocompatibility complex class I SLA-1 0401 and identification of 2009 pandemic swine-origin influenza A H1N1 virus cytotoxic T lymphocyte epitope peptides.

    PubMed

    Zhang, Nianzhi; Qi, Jianxun; Feng, Sijia; Gao, Feng; Liu, Jun; Pan, Xiaocheng; Chen, Rong; Li, Qirun; Chen, Zhaosan; Li, Xiaoying; Xia, Chun; Gao, George F

    2011-11-01

    The presentation of viral epitopes to cytotoxic T lymphocytes (CTLs) by swine leukocyte antigen class I (SLA I) is crucial for swine immunity. To illustrate the structural basis of swine CTL epitope presentation, the first SLA crystal structures, SLA-1 0401, complexed with peptides derived from either 2009 pandemic H1N1 (pH1N1) swine-origin influenza A virus (S-OIV(NW9); NSDTVGWSW) or Ebola virus (Ebola(AY9); ATAAATEAY) were determined in this study. The overall peptide-SLA-1 0401 structures resemble, as expected, the general conformations of other structure-solved peptide major histocompatibility complexes (pMHC). The major distinction of SLA-1 0401 is that Arg(156) has a "one-ballot veto" function in peptide binding, due to its flexible side chain. S-OIV(NW9) and Ebola(AY9) bind SLA-1 0401 with similar conformations but employ different water molecules to stabilize their binding. The side chain of P7 residues in both peptides is exposed, indicating that the epitopes are "featured" peptides presented by this SLA. Further analyses showed that SLA-1 0401 and human leukocyte antigen (HLA) class I HLA-A 0101 can present the same peptides, but in different conformations, demonstrating cross-species epitope presentation. CTL epitope peptides derived from 2009 pandemic S-OIV were screened and evaluated by the in vitro refolding method. Three peptides were identified as potential cross-species influenza virus (IV) CTL epitopes. The binding motif of SLA-1 0401 was proposed, and thermostabilities of key peptide-SLA-1 0401 complexes were analyzed by circular dichroism spectra. Our results not only provide the structural basis of peptide presentation by SLA I but also identify some IV CTL epitope peptides. These results will benefit both vaccine development and swine organ-based xenotransplantation.

  14. Crystal Structure of Swine Major Histocompatibility Complex Class I SLA-1*0401 and Identification of 2009 Pandemic Swine-Origin Influenza A H1N1 Virus Cytotoxic T Lymphocyte Epitope Peptides ▿

    PubMed Central

    Zhang, Nianzhi; Qi, Jianxun; Feng, Sijia; Gao, Feng; Liu, Jun; Pan, Xiaocheng; Chen, Rong; Li, Qirun; Chen, Zhaosan; Li, Xiaoying; Xia, Chun; Gao, George F.

    2011-01-01

    The presentation of viral epitopes to cytotoxic T lymphocytes (CTLs) by swine leukocyte antigen class I (SLA I) is crucial for swine immunity. To illustrate the structural basis of swine CTL epitope presentation, the first SLA crystal structures, SLA-1*0401, complexed with peptides derived from either 2009 pandemic H1N1 (pH1N1) swine-origin influenza A virus (S-OIVNW9; NSDTVGWSW) or Ebola virus (EbolaAY9; ATAAATEAY) were determined in this study. The overall peptide–SLA-1*0401 structures resemble, as expected, the general conformations of other structure-solved peptide major histocompatibility complexes (pMHC). The major distinction of SLA-1*0401 is that Arg156 has a “one-ballot veto” function in peptide binding, due to its flexible side chain. S-OIVNW9 and EbolaAY9 bind SLA-1*0401 with similar conformations but employ different water molecules to stabilize their binding. The side chain of P7 residues in both peptides is exposed, indicating that the epitopes are “featured” peptides presented by this SLA. Further analyses showed that SLA-1*0401 and human leukocyte antigen (HLA) class I HLA-A*0101 can present the same peptides, but in different conformations, demonstrating cross-species epitope presentation. CTL epitope peptides derived from 2009 pandemic S-OIV were screened and evaluated by the in vitro refolding method. Three peptides were identified as potential cross-species influenza virus (IV) CTL epitopes. The binding motif of SLA-1*0401 was proposed, and thermostabilities of key peptide–SLA-1*0401 complexes were analyzed by circular dichroism spectra. Our results not only provide the structural basis of peptide presentation by SLA I but also identify some IV CTL epitope peptides. These results will benefit both vaccine development and swine organ-based xenotransplantation. PMID:21900158

  15. Myelin basic protein-specific T lymphocyte repertoire in multiple sclerosis. Complexity of the response and dominance of nested epitopes due to recruitment of multiple T cell clones.

    PubMed Central

    Meinl, E; Weber, F; Drexler, K; Morelle, C; Ott, M; Saruhan-Direskeneli, G; Goebels, N; Ertl, B; Jechart, G; Giegerich, G

    1993-01-01

    The human T cell response to the myelin basic protein (MBP) has been studied with respect to T cell receptor (TCR) usage, HLA class II restriction elements, and epitope specificity using a total of 215 long-term MBP-specific T cell lines (TCL) isolated from the peripheral blood of 13 patients with multiple sclerosis (MS) and 10 healthy donors. In most donors, the anti-MBP response was exceedingly heterogeneous. Using a panel of overlapping synthetic peptides spanning the entire length of human MBP, at least 26 epitopes recognized by human TCL could be distinguished. The MBP domain most commonly recognized was sequence 80-105 (31% of MS TCL, and 24% of control TCL). Sequence 29-48 was recognized more frequently by control-derived TCL (24%) than by TCL from MS patients (5%). The MBP epitopes were recognized in the context of DRB1 *0101, DRB5*0101, DRB1*1501, DRB1*0301, DRB1*0401, DRB1*1402, and DRB3*0102, as demonstrated using a panel of DR gene-transfected L cells. The TCR gene usage was also heterogeneous. V beta 5.2, a peptide of which is currently being used in a clinical trial for treatment of MS patients, was expressed by only one of our TCL. However, within this complex pattern of MBP-specific T cell responses, a minority of MS patients were found to exhibit a more restricted response with respect to their TCL epitope specificity. In these patients 75-87% of the TCL responded to a single, patient-specific cluster of immunodominant T cell epitopes located within a small (20-amino acid) domain of MBP. These nested clusters of immunodominant epitopes were noted within the amino acids 80-105, 108-131, and 131-153. The T cell response to the immunodominant epitopes was not monoclonal, but heterogeneous, with respect to fine specificity, TCR usage, and even HLA restriction. In one patient (H.K.), this restricted epitope profile remained stable for > 2 yr. The TCR beta chain sequences of TCL specific for the immunodominant region of HK are consistent with an

  16. Novel immunodominant peptide presentation strategy: a featured HLA-A*2402-restricted cytotoxic T-lymphocyte epitope stabilized by intrachain hydrogen bonds from severe acute respiratory syndrome coronavirus nucleocapsid protein.

    PubMed

    Liu, Jun; Wu, Peng; Gao, Feng; Qi, Jianxun; Kawana-Tachikawa, Ai; Xie, Jing; Vavricka, Christopher J; Iwamoto, Aikichi; Li, Taisheng; Gao, George F

    2010-11-01

    Antigenic peptides recognized by virus-specific cytotoxic T lymphocytes (CTLs) are presented by major histocompatibility complex (MHC; or human leukocyte antigen [HLA] in humans) molecules, and the peptide selection and presentation strategy of the host has been studied to guide our understanding of cellular immunity and vaccine development. Here, a severe acute respiratory syndrome coronavirus (SARS-CoV) nucleocapsid (N) protein-derived CTL epitope, N1 (QFKDNVILL), restricted by HLA-A*2402 was identified by a series of in vitro studies, including a computer-assisted algorithm for prediction, stabilization of the peptide by co-refolding with HLA-A*2402 heavy chain and β(2)-microglobulin (β(2)m), and T2-A24 cell binding. Consequently, the antigenicity of the peptide was confirmed by enzyme-linked immunospot (ELISPOT), proliferation assays, and HLA-peptide complex tetramer staining using peripheral blood mononuclear cells (PBMCs) from donors who had recovered from SARS donors. Furthermore, the crystal structure of HLA-A*2402 complexed with peptide N1 was determined, and the featured peptide was characterized with two unexpected intrachain hydrogen bonds which augment the central residues to bulge out of the binding groove. This may contribute to the T-cell receptor (TCR) interaction, showing a host immunodominant peptide presentation strategy. Meanwhile, a rapid and efficient strategy is presented for the determination of naturally presented CTL epitopes in the context of given HLA alleles of interest from long immunogenic overlapping peptides.

  17. The life span of major histocompatibility complex-peptide complexes influences the efficiency of presentation and immunogenicity of two class I-restricted cytotoxic T lymphocyte epitopes in the Epstein-Barr virus nuclear antigen 4

    PubMed Central

    1996-01-01

    We have investigated the reactivity to two human histocompatibility leukocyte antigen (HLA) A11-restricted cytotoxic T lymphocyte (CTL) epitopes derived from amino acids 416-424 (IVTDFSVIK, designated IVT) and 399-408 (AVFDRKSVAK, designated AVF) of the Epstein-Barr virus (EBV) nuclear antigen (EBNA) 4. A strong predominance of CTL clones specific for the IVT epitope was demonstrated in polyclonal cultures generated by stimulation of lymphocytes from the EBV-seropositive donor BK with the autologous B95.8 virus-transformed lymphoblastoid cell line (LCL). This was not due to intrinsic differences of CTL efficiency since clones specific for the two epitopes lysed equally well A11- positive phytohemagglutinin blasts and LCLs pulsed with the relevant synthetic peptide. Irrespective of the endogenous levels of EBNA4 expression, untreated LCLs were lysed more efficiently by the IVT- specific effectors, suggesting that a higher density of A11-IVT complexes is presented at the cell surface. In accordance, 10-50-fold higher amounts of IVT peptides were found in high-performance liquid chromatography fractions of acid extracts corresponding to an abundance of about 350-12,800 IVT and 8-760 AVF molecules per cell. Peptide- mediated competition of CTL sensitization, transport assays in streptolysin-O permeabilized cells, and induction of A11 expression in the transporter associated with antigen presentation-deficient T2/A11 transfectant demonstrated that the IVT and AVF peptides bind with similar affinities to A11, are translocated with equal efficiency to the endoplasmic reticulum, and form complexes of comparable stability over a wide range of temperature and pH conditions. A rapid surface turnover of A11 molecules containing the AVF peptide was demonstrated in metabolically active T2/A11 cells corresponding to a half-life of approximately 3.5 as compared to approximately 2 h for molecules induced at 26 degrees C in the absence of exogenous peptides and >12 h for IVT

  18. DNA and modified vaccinia virus Ankara vaccines encoding multiple cytotoxic and helper T-lymphocyte epitopes of human immunodeficiency virus type 1 (HIV-1) are safe but weakly immunogenic in HIV-1-uninfected, vaccinia virus-naive adults.

    PubMed

    Gorse, Geoffrey J; Newman, Mark J; deCamp, Allan; Hay, Christine Mhorag; De Rosa, Stephen C; Noonan, Elizabeth; Livingston, Brian D; Fuchs, Jonathan D; Kalams, Spyros A; Cassis-Ghavami, Farah L

    2012-05-01

    We evaluated a DNA plasmid-vectored vaccine and a recombinant modified vaccinia virus Ankara vaccine (MVA-mBN32), each encoding cytotoxic and helper T-lymphocyte epitopes of human immunodeficiency virus type 1 (HIV-1) in a randomized, double-blinded, placebo-controlled trial in 36 HIV-1-uninfected adults using a heterologous prime-boost schedule. HIV-1-specific cellular immune responses, measured as interleukin-2 and/or gamma interferon production, were induced in 1 (4%) of 28 subjects after the first MVA-mBN32 immunization and in 3 (12%) of 25 subjects after the second MVA-mBN32 immunization. Among these responders, polyfunctional T-cell responses, including the production of tumor necrosis factor alpha and perforin, were detected. Vaccinia virus-specific antibodies were induced to the MVA vector in 27 (93%) of 29 and 26 (93%) of 28 subjects after the first and second immunizations with MVA-mBN32. These peptide-based vaccines were safe but were ineffective at inducing HIV-1-specific immune responses and induced much weaker responses than MVA vaccines expressing the entire open reading frames of HIV-1 proteins.

  19. Characterization of cloned class I MHC-restricted, CD8+ anti-Meth A cytotoxic T-lymphocytes: recognition of an epitope derived from the Meth A gp110 tumor rejection antigen.

    PubMed

    Fassanito, M A; Loftus, D; De Leo, R M; Law, L W; Appella, E; De Leo, A B

    1994-08-15

    Meth A gp110 has been tentatively identified as a tumor rejection antigen. Following isolation of a class I major histocompatibility complex (MHC)-restricted, CD8+ anti-Meth A cytotoxic T-lymphocyte (CTL), we sought to determine whether the determinant recognized by this CTL was: (a) functional in tumor rejection of Meth A sarcoma; and (b) derived from Meth A gp110. Initially, we isolated an anti-Meth A CTL-resistant variant of Meth A sarcoma, Meth A4R, by immunoselection. The results of the subsequent analysis of Meth A4R cells showed the CTL-defined determinant as having a functional role in transplantation rejection of Meth A sarcoma. Walker et al. (Proc. Natl. Acad. Sci. USA, 89: 7915-7918, 1993) showed that the cationic lipid, N-[1-(2,3-dioleoyloxy)propyl]-N,N,N- trimethylammonium-methyl sulfate, mediated delivery of a recombinant glycoprotein into the cytosol of target cells, making it available for processing and presentation by class I MHC molecules. As a result, the cells were sensitized for cytolysis by a class I MHC-restricted CD8+ CTL, which recognized an epitope expressed by the glycoprotein. In a similar manner, we treated the SV40-transformed BALB/c cell line, SVBalb, which is relatively insensitive to cytolysis by the anti-Meth A CTL, with Meth A gp110 and N-[1-(2,3-dioleoyloxy)propyl]-N,N,N-trimethylammonium methyl sulfate. The sensitivities of the treated cells and control cell lines to the anti-Meth A CTL were then examined. The results of these experiments permit us to conclude that the determinant recognized by the anti-Meth A CTL line is derived from Meth A gp110.

  20. Activated T lymphocytes in uveitis.

    PubMed Central

    Deschênes, J.; Char, D. H.; Kaleta, S.

    1988-01-01

    Two colour flow cytometry techniques were used to assess the activation stages of peripheral and intraocular T lymphocytes in uveitis. Increased numbers of T lymphocytes bearing the interleukin-2 (IL-2) receptors were found in intraocular fluids or peripheral blood or both of 35/51 patients with uveitis. This increased expression of IL-2 receptors on lymphocytes correlated with increased expression of other early T lymphocyte activation markers, HLA-DR and L-35. Both T helper cells (Leu-3A+) and suppressor cells (Leu 2A+) were activated in vivo. A positive correlation was seen between lymphocyte activation and clinical uveitis activity. In idiopathic uveitis activation of Leu-3A lymphocytes (helper/inducer) was significantly increased, and intraocular activation of the Leu-2A lymphocytes (cytotoxic/suppressor) was significantly decreased. These data show that some patients with idiopathic uveitis have a perturbation of T helper cells. Twenty-two of 31 patients with idiopathic uveitis, not associated with systemic disease, had increased peripheral T lymphocyte activation. This finding indicates that in some inflammations believed to be restricted to the eye an abnormal systemic immune activation exists. PMID:2964862

  1. The cloning of T lymphocytes.

    PubMed

    Schwartz, R H

    1982-02-01

    A new era of cellular immunology is clearly at hand. It is now possible, with a little bit of effort, to isolate monoclonal populations of T cells specific for any given antigen. The implications o f this technological advance are enormous in terms of applications to basic research and clinical medicine. In this article the two basic approaches that have been used to clone T lymphocytes are outlined, the pros and cons of each technique discussed and examples are given of recent experiments which have exploited this technology to gain new insights into T-cell specificity.

  2. Quantitation of Anaplasma marginale major surface protein (MSP)1a and MSP2 epitope-specific CD4+ T lymphocytes using bovine DRB3*1101 and DRB3*1201 tetramers.

    PubMed

    Norimine, Junzo; Han, Sushan; Brown, Wendy C

    2006-09-01

    Antigen-specific CD4+ T cells play a critical role in protective immunity to many infectious pathogens. Although the antigen-specific CD4+ T cells can be measured by functional assays such as proliferation or cytokine enzyme-linked immunospot, such assays are limited to a specific function and cannot quantify anergic or suppressed T cells. In contrast, major histocompatiblity complex (MHC) class II tetramers can enumerate epitope-specific CD4+ T cells independent of function. In this paper, we report the construction of bovine leukocyte antigen MHC class II tetramers using a novel mammalian cell system to express soluble class II DRA/DRB3 molecules and defined immunodominant peptide epitopes of Anaplasma marginale major surface proteins (MSPs). Phycoerythrin-labeled tetramers were either loaded with exogenous peptide or constructed with the peptide epitope linked to the N terminus of the DRB3 chain. A DRB3*1101 tetramer loaded with MSP1a peptide F2-5B (ARSVLETLAGHVDALG) and DRB3*1201 tetramers loaded with MSP1a peptide F2-1-1b (GEGYATYLAQAFA) or MSP2 peptide P16-7 (NFAYFGGELGVRFAF) specifically stained antigen-specific CD4+ T cell lines and clones. Tetramers constructed with the T-cell epitope linked to the DRB3 chain were slightly better at labeling CD4+ T cells. In one cell line, the number of tetramer-positive T cells increased to approximately 94% of the CD4+ T cells after culture for 21 weeks with specific antigen. This novel technology should be useful to track the fate of antigen-specific CD4+ T-cell responses in cattle after immunization or infection with persistent pathogens, such as A. marginale, that modulate the host immune response.

  3. How T lymphocytes see antigen

    NASA Astrophysics Data System (ADS)

    Chakraborty, Arup K.

    2009-03-01

    Complex organisms, like humans, have an adaptive immune system that enables us to do battle with diverse pathogens. This flexible system can also go awry, and many diseases are the direct consequence of the adaptive immune system failing to discriminate between markers of self and non-self. The orchestrators of adaptive immunity are a class of cells called T lymphocytes (T cells). T cells recognize minute numbers of molecular signatures of pathogens, and T cell recognition of these molecular markers of non-self is both specific and degenerate. The specific (yet, cross-reactive), diverse, and self-tolerant T cell repertoire is designed in the thymus. I will describe how an approach that brings together theoretical and computational studies (rooted in statistical physics) with experiments (carried out by key collaborators) has allowed us to shed light on the mechanistic principles underlying how T cells respond to pathogens in a digital fashion (``on'' or ``off''), and how this molecular machinery coupled with frustration (a la spin glasses) plays a key role in designing the special properties of the T cell repertoire during development in the thymus.

  4. Progranulin Inhibits Human T Lymphocyte Proliferation by Inducing the Formation of Regulatory T Lymphocytes

    PubMed Central

    Kwack, Kyu Hwan

    2017-01-01

    We have examined the effect of progranulin (PGRN) on human T cell proliferation and its underlying mechanism. We show that PGRN inhibits the PHA-induced multiplication of T lymphocytes. It increases the number of iTregs when T lymphocytes are activated by PHA but does not do so in the absence of PHA. PGRN-mediated inhibition of T lymphocyte proliferation, as well as the induction of iTregs, was completely reversed by a TGF-β inhibitor or a Treg inhibitor. PGRN induced TGF-β secretion in the presence of PHA whereas it did not in the absence of PHA. Our findings indicate that PGRN suppresses T lymphocyte proliferation by enhancing the formation of iTregs from activated T lymphocytes in response to TGF-β. PMID:28194047

  5. Dengue virus protein recognition by virus-specific murine CD8+ cytotoxic T lymphocytes.

    PubMed Central

    Rothman, A L; Kurane, I; Lai, C J; Bray, M; Falgout, B; Men, R; Ennis, F A

    1993-01-01

    The identification of the protein targets for dengue virus-specific T lymphocytes may be useful for planning the development of subunit vaccines against dengue. We studied the recognition by murine dengue virus-specific major histocompatibility complex class I-restricted, CD8+ cytotoxic T lymphocytes (CTL) of dengue virus proteins using recombinant vaccinia viruses containing segments of the dengue virus genome. CTL from H-2k mice recognized a single serotype-cross-reactive epitope on the nonstructural (NS) protein NS3. CTL from H-2b mice recognized a serotype-cross-reactive epitope that was localized to NS4a or NS4b. CTL from H-2d mice recognized at least three epitopes: a serotype-specific epitope on one of the structural proteins, a serotype-cross-reactive epitope on NS3, and a serotype-cross-reactive epitope on NS1 or NS2a. Our findings demonstrate the limited recognition of dengue virus proteins by CTL from three inbred mouse strains and the predominance of CTL epitopes on dengue virus nonstructural proteins, particularly NS3. Since human dengue virus-specific CTL show similar patterns of recognition, these findings suggest that nonstructural proteins should be considered in designing vaccines against dengue. PMID:7678307

  6. [Amalgam fillings and T-lymphocyte changes].

    PubMed

    Giuliani, M; Rumi, C; Marciani, F; Boari, A; Rumi, G; Di Felice, R

    1990-07-01

    Dental amalgam and nickel alloys have been considered quite safe. Previous authors reported the effect of dental amalgam and nickel alloys on human T-lymphocytes modifications after amalgam dental fillings, into dose-dependence of any modifications and into possible temporary. Eight patients were subjected to dental care with amalgam dental fillings. Drawings of blood were executed at start, fifteen days after late fillings and two months later. The results about modifications of T-lymphocytes were not univocal. We believe, at now, that temporary modifications of the immunity seem to be related to a cytotoxic mechanism.

  7. Mosaic vaccines elicit CD8+ T lymphocyte responses that confer enhanced immune coverage of diverse HIV strains in monkeys.

    PubMed

    Santra, Sampa; Liao, Hua-Xin; Zhang, Ruijin; Muldoon, Mark; Watson, Sydeaka; Fischer, Will; Theiler, James; Szinger, James; Balachandran, Harikrishnan; Buzby, Adam; Quinn, David; Parks, Robert J; Tsao, Chun-Yen; Carville, Angela; Mansfield, Keith G; Pavlakis, George N; Felber, Barbara K; Haynes, Barton F; Korber, Bette T; Letvin, Norman L

    2010-03-01

    An effective HIV vaccine must elicit immune responses that recognize genetically diverse viruses. It must generate CD8+ T lymphocytes that control HIV replication and CD4+ T lymphocytes that provide help for the generation and maintenance of both cellular and humoral immune responses against the virus. Creating immunogens that can elicit cellular immune responses against the genetically varied circulating isolates of HIV presents a key challenge for creating an HIV vaccine. Polyvalent mosaic immunogens derived by in silico recombination of natural strains of HIV are designed to induce cellular immune responses that recognize genetically diverse circulating virus isolates. Here we immunized rhesus monkeys by plasmid DNA prime and recombinant vaccinia virus boost with vaccine constructs expressing either consensus or polyvalent mosaic proteins. As compared to consensus immunogens, the mosaic immunogens elicited CD8+ T lymphocyte responses to more epitopes of each viral protein than did the consensus immunogens and to more variant sequences of CD8+ T lymphocyte epitopes. This increased breadth and depth of epitope recognition may contribute both to protection against infection by genetically diverse viruses and to the control of variant viruses that emerge as they mutate away from recognition by cytotoxic T lymphocytes.

  8. Intrinsic Photosensitivity Enhances Motility of T Lymphocytes

    PubMed Central

    Phan, Thieu X.; Jaruga, Barbara; Pingle, Sandeep C.; Bandyopadhyay, Bidhan C.; Ahern, Gerard P.

    2016-01-01

    Sunlight has important biological effects in human skin. Ultraviolet (UV) light striking the epidermis catalyzes the synthesis of Vitamin D and triggers melanin production. Although a causative element in skin cancers, sunlight is also associated with positive health outcomes including reduced incidences of autoimmune diseases and cancers. The mechanisms, however, by which light affects immune function remain unclear. Here we describe direct photon sensing in human and mouse T lymphocytes, a cell-type highly abundant in skin. Blue light irradiation at low doses (<300 mJ cm−2) triggers synthesis of hydrogen peroxide (H2O2) in T cells revealed by the genetically encoded reporter HyPerRed. In turn, H2O2 activates a Src kinase/phospholipase C-γ1 (PLC-γ1) signaling pathway and Ca2+ mobilization. Pharmacologic inhibition or genetic disruption of Lck kinase, PLC-γ1 or the T cell receptor complex inhibits light-evoked Ca2+ transients. Notably, both light and H2O2 enhance T-cell motility in a Lck-dependent manner. Thus, T lymphocytes possess intrinsic photosensitivity and this property may enhance their motility in skin. PMID:27995987

  9. Thymic influence on the T-lymphocyte self MHC repertoire. II. Cytotoxic T-lymphocyte precursors.

    PubMed

    Jenski, L J; Miller, B A

    1988-01-01

    We measured the frequency and specificity of thymic alloantigen-reactive cytotoxic T-lymphocyte precursors in spleens of allogeneic thymus-grafted nude mice tolerant to thymic alloantigens. Under our conditions of limiting dilution analysis we found no selective loss of cytotoxic T-lymphocyte precursors in allogeneic thymus-grafted mice. Upon analysis of individual cytotoxic T-lymphocyte clones, we found that lysis of specific and third party targets was mediated by distinct clones specific for H-2 antigens. Precursors from allogeneic thymus-grafted nudes stimulated at limiting dilutions with thymic alloantigens tended to lyse fewer targets than were lysed by normal cytotoxic T-lymphocytes or allogeneic thymus-grafted nude precursors stimulated with third party alloantigens, but the reduction in lytic activity was not statistically significant. Specific suppression was not demonstrated, but could not be ruled out unequivocally. We conclude that intrathymic deletion of thymic alloantigen-reactive pCTL is not necessary to achieve specific tolerance to thymic alloantigens.

  10. Clonotype analysis of cytomegalovirus-specific cytotoxic T lymphocytes.

    PubMed

    Babel, Nina; Brestrich, Gordon; Gondek, Lukasz P; Sattler, Arne; Wlodarski, Marcin W; Poliak, Nina; Bethke, Nicole; Thiel, Andreas; Hammer, Markus H; Reinke, Petra; Maciejewski, Jaroslaw P

    2009-02-01

    Cytotoxic T lymphocytes (CTL) control the replication of human cytomegalovirus (CMV). Previous studies assessed the clonotypic composition of CTL specific for individual immunodominant peptides within a certain HLA context. Such an approach has inherent limitations and may not assess the true clonal CTL response in vivo. Here, the clonotypic composition of CMV-specific CTL was determined in HLA-A2, CMV-seropositive kidney transplant recipients and healthy blood donors after stimulation of peripheral blood mononuclear cells with either a pp65 whole-peptide pool or a single immunodominant peptide. Even after stimulation with the whole peptide pool, CMV-specific CTL remained monoclonal or oligoclonal. Regarding intraindividual variation, the CDR3 motifs of the dominant clones were identical to those observed in CTL generated by the single immunodominant peptide. Sequencing of the CDR3 regions demonstrated significant interindividual variation; however, structural homology was observed for immunodominant clonotypes in three individuals. In conclusion, the highly focused T cell receptor repertoire found after stimulation with either a single immunodominant peptide or a peptide pool demonstrates a pivotal role for immunodominant epitopes in the generation of a clonal repertoire. These results provide new insights into the regulation of CMV clonal dominance and may contribute to the design and monitoring of adoptive immunotherapy.

  11. Effect of Malnutrition on K+ Current in T Lymphocytes

    PubMed Central

    Fernández, Rafael Godínez; Leehan, Joaquín Azpiroz; Pastrana, Reyna Fierro; Muñiz, Rocío Ortíz

    2005-01-01

    Severe malnutrition in children is frequently associated with infectious diseases. Animal models have been useful for studying the effects of malnutrition. One of the immunosuppressive mechanisms of malnutrition is inhibition of the activation of T lymphocytes. The voltage-dependent K(V) potassium channels are vital for the activation of T lymphocytes. The blockade of K(V) channels inhibits the activation of T lymphocytes. Malnutrition could affect the suitable synthesis of K(V) channels in T lymphocytes, producing changes in the magnitude and/or dependency of the voltage of the K+ current. We reported a significant decrease in the K+ current and activation to a 20 mV more positive membrane potential in T lymphocytes of rats with severe malnutrition. These results indicate that the diminution in the K+ conductance by alteration of K(V) channels in severe malnutrition is one of the mechanisms that inhibit the activation of T lymphocytes. PMID:16002627

  12. [Cytotoxic T lymphocytes in cancer and autoimmunity].

    PubMed

    Prado-García, Heriberto; Avila-Moreno, Federico; López-González, José Sullivan

    2004-01-01

    Cytotoxic T lymphocytes (CTLs) are cells of the immune system that recognize and kill cells that have been infected with intracellular pathogens, allogenic cells or tumor cells. It has been reported that CTLs participate in the pathogenesis of some autoimmune diseases. After stimulation with the antigen, CTLs undergo an activation process highly regulated, which leads to the cell to acquire an effector or memory function. In this review, we indicate the cellular markers associated with the different stages of CTL-differentiation (naive, memory and effector); we indicate the distinct models of CTLs differentiation; also, the mechanisms of CTLs cytotoxicity are mentioned. Furthermore, we describe the participation of CTLs in cancer and autoimmunity; the implications of CTLs in the progression of these diseases are discussed.

  13. Physiological implications of NTBI uptake by T lymphocytes

    PubMed Central

    Pinto, Jorge P.; Arezes, João; Dias, Vera; Oliveira, Susana; Vieira, Inês; Costa, Mónica; Vos, Matthijn; Carlsson, Anna; Rikers, Yuri; Rangel, Maria; Porto, Graça

    2014-01-01

    In iron overload disorders a significant fraction of the total iron circulates in the plasma as low molecular weight complexes not bound to transferrin, known as non-transferrin-bound iron (NTBI). By catalyzing the formation of free radicals, NTBI accumulation results in oxidative stress and cellular damage, being a major cause of organ toxicity. NTBI is rapidly and preferentially cleared from circulation by the liver and the myocardium, the main disease targets in iron overload conditions. We have recently demonstrated that human peripheral blood T lymphocytes take up NTBI in vitro, with a pattern that resembles that of hepatocytes. Since T lymphocytes constitute a numerically important component of the circulating cell pool, these findings support a putative role for this cell type in the systemic protection against iron toxicity. Here we tested the hypothesis that the circulating peripheral blood T lymphocyte pool constitutes an important storage compartment for NTBI and is thus a modifier of NTBI deposition in target organs. First we show that NTBI uptake by human T lymphocytes increases the expression of the iron-storage protein ferritin and of the iron exporter ferroportin via an IRE-dependent mechanism. NTBI retention by T lymphocytes is shown to be critically controlled by the hepcidin-mediated modulation of ferroportin both in vitro and in vivo. Finally, the protective effect of T lymphocytes was tested by analyzing the patterns of iron accumulation in the T lymphocyte-deficient mouse model Foxn1nu before and after reconstitution with T lymphocytes by adoptive transfer. The results confirmed a significant increase of liver and pancreas iron accumulation in T lymphocyte-deficient mice. NTBI accumulation in the liver and spleen was prevented by reconstitution with syngeneic T lymphocytes. Altogether, our results demonstrate that T lymphocytes are important components of a circulating “NTBI storage compartment” and show its physiological relevance as a

  14. Signal transduction in T lymphocytes in microgravity

    NASA Technical Reports Server (NTRS)

    Cogoli, A.

    1997-01-01

    More than 120 experiments conducted in space in the last 15 years have shown that dramatic changes are occurring in several types of single cells during their exposure to microgravity. One focus of today's research on cells in space is on signal transduction, especially those steps involving the cytoskeleton and cell-cell interactions. Signal transduction is often altered in microgravity as well as in hypergravity. This leads to changes in cell proliferation, genetic expression and differentiation. Interesting examples are leukocytes, HeLa cells, epidermoid cells and osteoblastic cells. Signalling pathways were studied in T lymphocytes in microgravity by several investigators after the discovery that mitogenic activation in vitro is virtually nil at 0g. T cells are a good model to study signal transduction because three extracellular signals (mitogen, IL-1 and IL-2) are required for full activation, and two classical pathways (via proteins G and PKC) are activated within the cell. In addition, low molecular weight GTP-binding proteins (Ras and Rap) are interacting with the cytoskeleton. The data at 0g support the notion that the expression of IL-2 receptor is inhibited at 0g, while mitogen binding and the transmission of IL-1 by accessory cells occur normally. In addition, alterations of the cytoskeleton suggest that the interaction with Rap proteins is disturbed. Data obtained with phorbol esters indicate that the function of PKC is changed in microgravity. Similar conclusions are drawn from the results with epidermoid cells A431.

  15. Subsets of T lymphocytes in relation to T lymphocyte function in multiple sclerosis.

    PubMed Central

    Craig, J C; Hawkins, S A; Swallow, M W; Lyttle, J A; Patterson, V H; Merrett, J D; Haire, M

    1985-01-01

    T lymphocyte control of Epstein-Barr virus (EBV) infection of autologous B lymphocytes was examined in parallel to the enumeration of subpopulations of mononuclear cells in 22 multiple sclerosis (MS) patients and in 22 healthy individuals. All were seropositive for EBV. The incidence of lack of T cell control was significantly higher in patients than in controls, confirming previous published work. In the present study, we have shown in addition a significantly reduced proportion of OKT8+ cells and a significantly increased ratio of OKT4/OKT8 cells in the group of patients with lack of control. The findings point to abnormal immunoregulation in MS. PMID:3000660

  16. Peptide microarrays for the profiling of cytotoxic T-lymphocyte activity using minimum numbers of cells.

    PubMed

    Hoff, Antje; Bagû, Ana-Cristina; André, Thomas; Roth, Günter; Wiesmüller, Karl-Heinz; Gückel, Brigitte; Brock, Roland

    2010-09-01

    The identification of epitopes that elicit cytotoxic T-lymphocyte activity is a prerequisite for the development of cancer-specific immunotherapies. However, especially the parallel characterization of several epitopes is limited by the availability of T cells. Microarrays have enabled an unprecedented miniaturization and parallelization in biological assays. Here, we developed peptide microarrays for the detection of CTL activity. MHC class I-binding peptide epitopes were pipetted onto polymer-coated glass slides. Target cells, loaded with the cell-impermeant dye calcein, were incubated on these arrays, followed by incubation with antigen-expanded CTLs. Cytotoxic activity was detected by release of calcein and detachment of target cells. With only 200,000 cells per microarray, CTLs could be detected at a frequency of 0.5% corresponding to 1,000 antigen-specific T cells. Target cells and CTLs only settled on peptide spots enabling a clear separation of individual epitopes. Even though no physical boundaries were present between the individual spots, peptide loading only occurred locally and cytolytic activity was confined to the spots carrying the specific epitope. The peptide microarrays provide a robust platform that implements the whole process from antigen presentation to the detection of CTL activity in a miniaturized format. The method surpasses all established methods in the minimum numbers of cells required. With antigen uptake occurring on the microarray, further applications are foreseen in the testing of antigen precursors that require uptake and processing prior to presentation.

  17. Asymmetric cell division in T lymphocyte fate diversification

    PubMed Central

    Arsenio, Janilyn; Metz, Patrick J.

    2015-01-01

    Immunological protection against microbial pathogens is dependent on robust generation of functionally diverse T lymphocyte subsets. Upon microbial infection, naïve CD4+ or CD8+ T lymphocytes can give rise to effector- and memory-fated progeny that together mediate a potent immune response. Recent advances in single-cell immunological and genomic profiling technologies have helped elucidate early and late diversification mechanisms that enable the generation of heterogeneity from single T lymphocytes. We discuss these findings here and argue that one such mechanism, asymmetric cell division, creates an early divergence in T lymphocyte fates by giving rise to daughter cells with a propensity towards the terminally differentiated effector or self-renewing memory lineages, with cell-intrinsic and -extrinsic cues from the microenvironment driving the final maturation steps. PMID:26474675

  18. Evolution of viral life-cycle in response to cytotoxic T lymphocyte-mediated immunity.

    PubMed

    Louzoun, Yoram; Ganusov, Vitaly V

    2012-10-07

    Viruses in mammals are constantly faced with the problem of elimination by the host immunity. Cytotoxic T lymphocyte (CTL) responses are thought to play a major role in the control and clearance of several viral infections in mice and humans. It is therefore expected that over evolutionary time, viruses would be forced to evolve to avoid recognition by CTLs. Indeed, a number of studies have documented the accumulation of viral variants with escape mutations. These mutations allow viruses to hide from CTL responses common in the host population. CTLs recognize viruses by short protein sequences, named epitopes, derived from viral proteins. The efficiency of viral recognition by epitope-specific CTL responses depends on the expression pattern of the proteins carrying these epitopes, and the total amount of that protein (and thus epitopes) in the cell. When a virus replicates in a cell, some viral genes are expressed early in the life cycle of the virus, while other proteins are expressed late. For example, HIV infected cells first express Rev and Tat proteins, and the Gag proteins are expressed late. Here we propose a dynamical model of the viral life cycle to study how expression level of early vs. late genes may affect viral dynamics within the host and virus transmission over the course of infection. We find that for acute and chronic viral infections lower expression of early genes than that of the late genes is expected to give selective advantage and higher transmission to viruses.

  19. The Role of the T lymphocytes and Remodeling in Asthma.

    PubMed

    Amin, Kawa

    2016-08-01

    In allergic asthma (AA), inflammatory changes in the airway epithelium may contribute to the characteristic pathophysiology and symptoms. The presence of T lymphocytes, eosinophils, mast cells and macrophages, the presence of cytokines, and also structural changes in the airway mucous membrane are characteristic for asthma. Bronchial biopsy specimens were obtained from 33 AA, 25 nonallergic asthma (NAA), and 20 healthy controls (HC). This study used immunohistochemical techniques for identified monoclonal antibodies (CD3, CD4, CD8, CD25, ECP, MBP, tenascin, and laminin) in the bronchi. The highest number of eosinophils and T lymphocyte cells in bronchial biopsies was found in AA, and NAA. The number of T lymphocytes in AA was significantly higher than in NAA and HC. The degree of epithelial damage was higher in the AA group compared to the other groups. The tenascin- and laminin-positive layers in AA were thicker than other groups. In AA, a significant negative correlation was found between epithelial integrity and the count for eosinophils or T lymphocytes. T lymphocytes and eosinophils in AA were found in the area of epithelial and lamina propria damage. This article suggests that T lymphocytes may not only contribute to the chronic airway inflammatory response, airway remodeling, and symptomatology but may also have a central role at the initiation of the allergic immune response. Th-targeted therapy would be of considerable interest in controlling AA. Having more knowledge on the roles of T lymphocytes in the pathogenesis of allergic inflammation highlights the contributions of these cells in regulating and may lead to a new therapeutic target-AA.

  20. Thymic influence on the T-lymphocyte self MHC repertoire. I. Helper T-lymphocyte precursors.

    PubMed

    Jenski, L J; Belloni, M L; Miller, B A

    1988-01-01

    We measured the frequencies of helper T-cell precursors in spleens of allogeneic thymus-grafted nude mice to determine whether allogeneic thymus engraftment resulted in clonal deletion of helper T-cells reactive to thymic major histocompatibility complex alloantigens, thereby producing tolerance to the thymic alloantigens. C3H thymus-grafted nudes had nearly normal numbers of C3H-reactive helper T-cell precursors, whereas C57BL/6 thymus-grafted nudes had significantly reduced numbers of C57BL/6-reactive helper T-cell precursors. Additional evidence suggested that tolerance was not due to a paucity of helper T-cell precursors: a) there was no correlation between the helper T-cell precursor frequency and the ability to mount cytotoxic responses against the thymic alloantigens, and b) exogenous helper factors did not break cytotoxic T-lymphocyte tolerance to thymic alloantigens. Thus, we conclude that immune tolerance resulting from engraftment of allogeneic thymic tissue is not necessarily due to clonal deletion of specific helper T-cell precursors.

  1. Multiple Sclerosis and T Lymphocytes: An Entangled Story

    PubMed Central

    Legroux, Laurine; Arbour, Nathalie

    2016-01-01

    Multiple sclerosis (MS) is the prototypic inflammatory disease of the central nervous system (CNS) characterized by multifocal areas of demyelination, axonal damage, activation of glial cells, and immune cell infiltration. Despite intensive years of research, the etiology of this neurological disorder remains elusive. Nevertheless, the abundance of immune cells such as T lymphocytes and their products in CNS lesions of MS patients supports the notion that MS is an immune-mediated disorder. An important body of evidence gathered from MS animal models such as experimental autoimmune encephalomyelitis (EAE), points to the central contribution of CD4 T lymphocytes in disease pathogenesis. Both Th1 (producing interferon-γ) and Th17 (producing interleukin 17) CD4 T lymphocytes targeting CNS self-antigens have been implicated in MS and EAE pathobiology. Moreover, several publications suggest that CD8 T lymphocytes also participate in the development of MS lesions. The migration of activated T lymphocytes from the periphery into the CNS has been identified as a crucial step in the formation of MS lesions. Several factors promote such T cell extravasation including: molecules (e.g., cell adhesion molecules) implicated in the T cell-blood brain barrier interaction, and chemokines produced by neural cells. Finally, once in the CNS, T lymphocytes need to be reactivated by local antigen presenting cells prior to enter the parenchyma where they can initiate damage. Further investigations will be necessary to elucidate the impact of environmental factors (e.g., gut microbiota) and CNS intrinsic properties (e.g., microglial activation) on this inflammatory neurological disease. PMID:25946987

  2. Psychosocial factors and T lymphocyte counts in Brazilian peacekeepers

    PubMed Central

    Monteiro da Silva, Angela M; Speranza, Francisco A B; Ishii, Solange Kiyoko; Hirata, Raphael; Mattos-Guaraldi, Ana Luíza; Milagres, Lucimar Gonçalves

    2015-01-01

    OBJECTIVE: To investigate the associations between psychosocial factors and peripheral blood CD4 and CD8 T lymphocyte numbers in Brazilian peacekeepers. METHODS: Venous blood was collected from 759 peacekeepers who had just returned from a peace mission in Haiti. Among the 759 soldiers, 642 individuals completed the psychosocial measures. CD4 and CD8 T lymphocyte counts were measured by flow cytometry using a commercially available kit. Psychosocial factors, including military peace force stressors, clinical stress, anxiety and depression, were recorded. As a reference for T lymphocyte numbers, we measured T lymphocyte counts in 75 blood donors from the Instituto de Biologia do Exército, Rio de Janeiro. RESULTS: The median numbers of CD4 and CD8 T lymphocytes in the blood donors were 819 cells/µl and 496 cells/µl, respectively, with a CD4:CD8 ratio of 1.6. Significantly (p<0.05) lower CD4 T cell counts (759 cells/µl) were recorded for peacekeepers, with similar CD8 levels (548 cells/µl) and smaller CD4:CD8 ratios (1.3, p<0.001) compared to blood donors. These differences were due to a group of 14 military personnel with CD4 and CD8 medians of 308 and 266 cells/µl, respectively. Only one (7.1%) of these 14 individuals was diagnosed with clinical stress compared with 13.5% of the individuals with normal levels of CD4 T lymphocytes. One individual out of 628 (0.16%) had a Lipp's Stress Symptom Inventory score of 3, indicating near exhaustion. CONCLUSION: The prevalence of psychological disorders was low and there were no associations with CD4 or CD8 T cell numbers. PMID:25789525

  3. Cytotoxic T lymphocytes specific for the simian immunodeficiency virus.

    PubMed

    Letvin, N L; Schmitz, J E; Jordan, H L; Seth, A; Hirsch, V M; Reimann, K A; Kuroda, M J

    1999-08-01

    A non-human primate model for acquired immunodeficiency syndrome (AIDS), the simian immunodeficiency virus (SIV)-infected rhesus monkey, was used to explore the role of the AIDS virus-specific cytotoxic T-lymphocyte (CTL) response in disease pathogenesis. This CTL response was measured using the major histocompatibility complex (MHC) class I/peptide tetramer technology. Large numbers of tetramer-binding CD8+ T lymphocytes were demonstrable not only in the peripheral blood, but in lymph nodes and even in semen of chronically SIV-infected monkeys. The central role of these effector T lymphocytes in containing SIV spread during primary infection was demonstrated by showing that early SIV clearance during primary infection correlated with the emergence of the tetramer binding CD8+ T lymphocytes and that in vivo depletion of CD8+ lymphocytes eliminated the ability of the infected monkeys to contain SIV replication. These observations suggest that an effective AIDS vaccine should elicit a potent virus-specific CTL response. In fact, a live, recombinant SIV vaccine constructed using the attenuated pox virus vector modified vaccinia Ankara (MVA) elicited a high-frequency CTL response, comparable in magnitude to that elicited by SIV infection itself. This suggests that vaccine modalities such as MVA may prove useful in creating an effective human immunodeficiency virus (HIV) vaccine. These studies also indicate the power of both the SIV/macaque model and MHC class I/peptide tetramers for assessing AIDS vaccine strategies.

  4. Trivalent live attenuated influenza-simian immunodeficiency virus vaccines: efficacy and evolution of cytotoxic T lymphocyte escape in macaques.

    PubMed

    Reece, Jeanette C; Alcantara, Sheilajen; Gooneratne, Shayarana; Jegaskanda, Sinthujan; Amaresena, Thakshila; Fernandez, Caroline S; Laurie, Karen; Hurt, Aeron; O'Connor, Shelby L; Harris, Max; Petravic, Janka; Martyushev, Alexey; Grimm, Andrew; Davenport, Miles P; Stambas, John; De Rose, Robert; Kent, Stephen J

    2013-04-01

    There is an urgent need for a human immunodeficiency virus (HIV) vaccine that induces robust mucosal immunity. CD8(+) cytotoxic T lymphocytes (CTLs) apply substantial antiviral pressure, but CTLs to individual epitopes select for immune escape variants in both HIV in humans and SIV in macaques. Inducing multiple simian immunodeficiency virus (SIV)-specific CTLs may assist in controlling viremia. We vaccinated 10 Mane-A1*08401(+) female pigtail macaques with recombinant influenza viruses expressing three Mane-A1*08401-restricted SIV-specific CTL epitopes and subsequently challenged the animals, along with five controls, intravaginally with SIV(mac251). Seroconversion to the influenza virus vector resulted and small, but detectable, SIV-specific CTL responses were induced. There was a boost in CTL responses after challenge but no protection from high-level viremia or CD4 depletion was observed. All three CTL epitopes underwent a coordinated pattern of immune escape during early SIV infection. CTL escape was more rapid in the vaccinees than in the controls at the more dominant CTL epitopes. Although CTL escape can incur a "fitness" cost to the virus, a putative compensatory mutation 20 amino acids upstream from an immunodominant Gag CTL epitope also evolved soon after the primary CTL escape mutation. We conclude that vaccines based only on CTL epitopes will likely be undermined by rapid evolution of both CTL escape and compensatory mutations. More potent and possibly broader immune responses may be required to protect pigtail macaques from SIV.

  5. Early HLA-B*57-Restricted CD8+ T Lymphocyte Responses Predict HIV-1 Disease Progression

    PubMed Central

    Ibarrondo, F. Javier; Sugar, Catherine A.; Hausner, Mary Ann; Shih, Roger; Ng, Hwee L.; Detels, Roger; Margolick, Joseph B.; Rinaldo, Charles R.; Phair, John; Jacobson, Lisa P.; Yang, Otto O.

    2012-01-01

    Although HLA-B*57 (B57) is associated with slow progression to disease following HIV-1 infection, B57 heterozygotes display a wide spectrum of outcomes, including rapid progression, viremic slow progression, and elite control. Efforts to identify differences between B57-positive (B57+) slow progressors and B57+ rapid progressors have largely focused on cytotoxic T lymphocyte (CTL) phenotypes and specificities during chronic stages of infection. Although CTL responses in the early months of infection are likely to be the most important for the long-term rate of HIV-1 disease progression, few data on the early CTL responses of eventual slow progressors have been available. Utilizing the Multicenter AIDS Cohort Study (MACS), we retrospectively examined the early HIV-1-specific CTL responses of 14 B57+ individuals whose time to development of disease ranged from 3.5 years to longer than 25 years after infection. In general, a greater breadth of targeting of epitopes from structural proteins, especially Gag, as well as of highly conserved epitopes from any HIV-1 protein, correlated with longer times until disease. The single elite controller in the cohort was an outlier on several correlations of CTL targeting and time until disease, consistent with reports that elite control is typically not achieved solely by protective HLA-mediated CTLs. When targeting of individual epitopes was analyzed, we found that early CTL responses to the IW9 (ISPRTLNAW) epitope of Gag, while generally subdominant, correlated with delayed progression to disease. This is the first study to identify early CTL responses to IW9 as a correlate of protection in persons with HLA-B*57. PMID:22811521

  6. Mathematical modeling of escape of HIV from cytotoxic T lymphocyte responses

    NASA Astrophysics Data System (ADS)

    Ganusov, Vitaly V.; Neher, Richard A.; Perelson, Alan S.

    2013-01-01

    Human immunodeficiency virus (HIV-1 or simply HIV) induces a persistent infection, which in the absence of treatment leads to AIDS and death in almost all infected individuals. HIV infection elicits a vigorous immune response starting about 2-3 weeks postinfection that can lower the amount of virus in the body, but which cannot eradicate the virus. How HIV establishes a chronic infection in the face of a strong immune response remains poorly understood. It has been shown that HIV is able to rapidly change its proteins via mutation to evade recognition by virus-specific cytotoxic T lymphocytes (CTLs). Typically, an HIV-infected patient will generate 4-12 CTL responses specific for parts of viral proteins called epitopes. Such CTL responses lead to strong selective pressure to change the viral sequences encoding these epitopes so as to avoid CTL recognition. Indeed, the viral population ‘escapes’ from about half of the CTL responses by mutation in the first year. Here we review experimental data on HIV evolution in response to CTL pressure, mathematical models developed to explain this evolution, and highlight problems associated with the data and previous modeling efforts. We show that estimates of the strength of the epitope-specific CTL response depend on the method used to fit models to experimental data and on the assumptions made regarding how mutants are generated during infection. We illustrate that allowing CTL responses to decay over time may improve the model fit to experimental data and provides higher estimates of the killing efficacy of HIV-specific CTLs. We also propose a novel method for simultaneously estimating the killing efficacy of multiple CTL populations specific for different epitopes of HIV using stochastic simulations. Lastly, we show that current estimates of the efficacy at which HIV-specific CTLs clear virus-infected cells can be improved by more frequent sampling of viral sequences and by combining data on sequence evolution with

  7. In vitro selection of lymphocytic choriomeningitis virus escape mutants by cytotoxic T lymphocytes.

    PubMed Central

    Aebischer, T; Moskophidis, D; Rohrer, U H; Zinkernagel, R M; Hengartner, H

    1991-01-01

    Cytotoxic T lymphocyte (CTL)-mediated cytolysis is induced via the interaction of the specific T-cell antigen receptor and the peptidic viral antigen associated with the major histocompatibility complex class I antigen. Here we demonstrate in vitro that lymphocytic choriomeningitis virus (LCMV) can escape the cytotoxic activity of LCMV-specific cloned CTLs by single amino acid changes within the recognized T-cell epitope defined by residues 275-289 of the LCMV glycoprotein [LCMV-GP-(275-289)]. LCMV-infected fibroblasts at a multiplicity of infection of 10(-3) exposed to virus-specific CTL at an effector-to-target cell ratio of 4:1 4 hr after infection was optimal for virus mutant selection. The selections were carried out with three LCMV-GP-(275-289)-specific CTL clones expressing T-cell antigen receptors containing the identical variable gene segments V alpha 4 and V beta 10 but different junctional regions; selection was also possible with LCMV-GP-(275-289)-specific cytotoxic polyclonal T cells. The most common escape mutation was an amino acid change of asparagine (AAT) to aspartic acid (GAT) at position 280; an additional mutation was glycine (GGT) to aspartic acid (GAT) at position 282. The results presented show that relevant point mutations within the T-cell epitope of LCMV-GP-(275-289) occur frequently and that they are selectable in vitro by CTLs. Images PMID:1722316

  8. Role of interleukin 1 in the activation of T lymphocytes.

    PubMed Central

    Lichtman, A H; Chin, J; Schmidt, J A; Abbas, A K

    1988-01-01

    The activation of T lymphocytes requires their stimulation via clonotypic antigen receptors as well as nonantigen-specific costimulators, the best defined of which is the cytokine interleukin 1 (IL-1). Recent studies have shown that murine CD4+ helper T lymphocytes consist of two nonoverlapping subsets that selectively utilize interleukin 2 (IL-2) or interleukin 4 as their autocrine growth factors and are called Th1 and Th2 cells, respectively. We now show that IL-1 functions as a costimulator for the proliferation of Th2 but not of Th1 clones and only Th2 cells express high-affinity receptors for IL-1. Secretion of autocrine growth-promoting lymphokines by Th1 and Th2 cells occurs after stimulation via the antigen receptor-CD3 complex and is neither dependent on nor affected by IL-1. These findings suggest that the activation of T lymphocytes can be divided into two stages, lymphokine secretion and proliferation, and only proliferation requires costimulators such as IL-1. Moreover, the prevailing view that IL-1 functions as a costimulator by inducing secretion of IL-2 or expression of IL-2 receptors may not be generally applicable, because IL-2-producing Th1 clones do not express receptors for IL-1 and are insensitive to this cytokine. Images PMID:3264404

  9. Control of T lymphocyte morphology by the GTPase Rho

    NASA Technical Reports Server (NTRS)

    Woodside, Darren G.; Wooten, David K.; Teague, T. Kent; Miyamoto, Yuko J.; Caudell, Eva G.; Udagawa, Taturo; Andruss, Bernard F.; McIntyre, Bradley W.

    2003-01-01

    BACKGROUND: Rho family GTPase regulation of the actin cytoskeleton governs a variety of cell responses. In this report, we have analyzed the role of the GTPase Rho in maintenance of the T lymphocyte actin cytoskeleton. RESULTS: Inactivation of the GTPase Rho in the human T lymphocytic cell line HPB-ALL does not inhibit constitutively high adhesion to the integrin beta1 substrate fibronectin. It did however result in the aberrant extension of finger-like dendritic processes on the substrates VCAM-1, Fn, and mAb specific to beta1 integrins. Time-lapse video microscopy demonstrated that C3 induced extensions were primarily the result of an altered pseudopod elongation rather than retraction. Once the stellate pseudopodia extended, none retracted, and cells became completely immobile. Filipodial structures were absent and the dendritic-like processes in C3 treated cells were rich in filamentous actin. Immunolocalization of RhoA in untreated HPB-ALL cells spreading on fibronectin demonstrated a diffuse staining pattern within the pseudopodia. In C3 treated cells, clusters of RhoA were pronounced and localized within the altered extensions. CONCLUSIONS: GTPase Rho is actively involved in the regulation of T lymphocyte morphology and motility.

  10. IAN family critically regulates survival and development of T lymphocytes.

    PubMed

    Nitta, Takeshi; Nasreen, Mariam; Seike, Takafumi; Goji, Atsushi; Ohigashi, Izumi; Miyazaki, Tadaaki; Ohta, Tsutomu; Kanno, Masamoto; Takahama, Yousuke

    2006-04-01

    The IAN (immune-associated nucleotide-binding protein) family is a family of functionally uncharacterized GTP-binding proteins expressed in vertebrate immune cells and in plant cells during antibacterial responses. Here we show that all eight IAN family genes encoded in a single cluster of mouse genome are predominantly expressed in lymphocytes, and that the expression of IAN1, IAN4, and IAN5 is significantly elevated upon thymic selection of T lymphocytes. Gain-of-function experiments show that the premature overexpression of IAN1 kills immature thymocytes, whereas short hairpin RNA-mediated loss-of-function studies show that IAN4 supports positive selection. The knockdown of IAN5 perturbs the optimal generation of CD4/CD8 double-positive thymocytes and reduces the survival of mature T lymphocytes. We also show evidence suggesting that IAN4 and IAN5 are associated with anti-apoptotic proteins Bcl-2 and Bcl-xL, whereas IAN1 is associated with pro-apoptotic Bax. Thus, the IAN family is a novel family of T cell-receptor-responsive proteins that critically regulate thymic development and survival of T lymphocytes and that potentially exert regulatory functions through the association with Bcl-2 family proteins.

  11. Recognition of Highly Diverse Type-1 and -2 Porcine Reproductive and Respiratory Syndrome Viruses (PRRSVs) by T-Lymphocytes Induced in Pigs after Experimental Infection with a Type-2 PRRSV Strain

    PubMed Central

    Cha, Sang-Ho; Grimm, Amanda L.; Chung, Grace; Gibson, Kathleen A.; Yoon, Kyoung-Jin; Parish, Steven M.; Ho, Chak-Sum; Lee, Stephen S.

    2016-01-01

    Background/Aim Live attenuated vaccines confer partial protection in pigs before the appearance of neutralizing antibodies, suggesting the contribution of cell-mediated immunity (CMI). However, PRRSV-specific T-lymphocyte responses and protective mechanisms need to be further defined. To this end, the hypothesis was tested that PRRSV-specific T-lymphocytes induced by exposure to type-2 PRRSV can recognize diverse isolates. Methods An IFN-gamma ELISpot assay was used to enumerate PRRSV-specific T-lymphocytes from PRRSVSD23983-infected gilts and piglets born after in utero infection against 12 serologically and genetically distinct type-1 and -2 PRRSV isolates. The IFN-gamma ELISpot assay using synthetic peptides spanning all open reading frames of PRRSVSD23983 was utilized to localize epitopes recognized by T-lymphocytes. Virus neutralization tests were carried out using the challenge strain (type-2 PRRSVSD23983) and another strain (type-2 PRRSVVR2332) with high genetic similarity to evaluate cross-reactivity of neutralizing antibodies in gilts after PRRSVSD23983 infection. Results At 72 days post infection, T-lymphocytes from one of three PRRSVSD23983-infected gilts recognized all 12 diverse PRRSV isolates, while T-lymphocytes from the other two gilts recognized all but one isolate. Furthermore, five of nine 14-day-old piglets infected in utero with PRRSVSD23983 had broadly reactive T-lymphocytes, including one piglet that recognized all 12 isolates. Overlapping peptides encompassing all open reading frames of PRRSVSD23983 were used to identify ≥28 peptides with T-lymphocyte epitopes from 10 viral proteins. This included one peptide from the M protein that was recognized by T-lymphocytes from all three gilts representing two completely mismatched MHC haplotypes. In contrast to the broadly reactive T-lymphocytes, neutralizing antibody responses were specific to the infecting PRRSVSD23983 isolate. Conclusion These results demonstrated that T-lymphocytes recognizing

  12. T-lymphocyte induction of human monocyte angiotensin converting enzyme (ACE) is not dependent upon T-lymphocyte proliferation

    SciTech Connect

    Vuk-Pavlovic, Z.; Rohrbach, M.S.

    1986-03-05

    Human peripheral blood monocytes cultured in serum free media for seven days show a basal activity of the ectoenzyme ACE which is augmented 2-3 times by the presence of autologous peripheral blood T-lymphocytes. Since these two cell types are also involved in autologous mixed lymphocyte reaction if serum is present, the authors compared the ability of T-cells to stimulate ACE activity in the presence or absence of proliferation (measured by /sup 3/H-thymidine incorporation). By the seventh day, cultures with 5% AB/sup +/ serum showed significant increase in proliferation but no increase in ACE activity compared to the serum free cultures. Even higher proliferation rate achieved by co-culturing T-lymphocytes with allogeneic monocytes did not increase ACE production; on the contrary, ACE activity remained at the basal level. Monocyte-T-cell co-cultures stimulated with increasing concentrations of ConA or PHA showed dose dependent increases in proliferation but parallel decreases in ACE activity. Addition of soluble antigen (Candida albicans) also enhanced proliferation but not ACE synthesis. They conclude that T-lymphocyte induction of monocyte ACE is a result of cooperation between autologous cells which is not dependent upon T-cell proliferation.

  13. Selective Killing of T Lymphocytes by Phototoxic Liposomes

    NASA Astrophysics Data System (ADS)

    Yemul, Shrishailam; Berger, Carole; Estabrook, Alison; Suarez, Sylvia; Edelson, Richard; Bayley, Hagan

    1987-01-01

    Two-fold specificity in drug delivery obtained through (i) the localized activation of drugs by physical means and (ii) the attachment of drugs to proteins that bind to target cells might be used for highly selective cancer chemotherapy or for immunosuppression. Toward this end, a monoclonal antibody against an antigen on the surface of T lymphocytes was covalently attached to liposomes containing a phototoxic drug, pyrene, bound to the lipid bilayer. When unfractionated peripheral blood lymphocytes, or B- and T-cell lines, were irradiated after treatment with these liposomes, T cells were killed while B cells were spared, demonstrating the validity of the approach in a simple in vitro assay.

  14. New insights into HIV-1 specific cytotoxic T-lymphocyte responses in exposed, persistently seronegative Kenyan sex workers.

    PubMed

    Kaul, R; Rowland-Jones, S L; Kimani, J; Fowke, K; Dong, T; Kiama, P; Rutherford, J; Njagi, E; Mwangi, F; Rostron, T; Onyango, J; Oyugi, J; MacDonald, K S; Bwayo, J J; Plummer, F A

    2001-11-01

    A clearer understanding of HIV-1 specific immune responses in highly-exposed, persistently seronegative (HEPS) subjects is important in developing models of HIV-1 protective immunity. HIV-1 specific cytotoxic T-lymphocytes (CTL) have been described in a cohort of HEPS Kenyan sex workers, and recent work has further elucidated these responses. CTL specific for HIV-1 Env were found in the blood of over half the sex workers meeting criteria for HIV resistance, and in some women recognized unmapped epitopes. The proportion of women with Env-specific CTL increased with the duration of uninfected HIV exposure, suggesting that these responses were acquired over time. CD8+ lymphocyte responses directed against predefined HIV-1 CTL epitopes from various HIV-1 genes were found in the blood and genital tract of >50% resistant sex workers, at a ten-fold lower frequency than in infected subjects. The epitope specificity of CD8+ responses differs between HEPS and HIV infected women, and in HEPS the maintenance of responses appears to be dependent on persistent HIV exposure. Several HIV-1 'resistant' sex workers have become HIV infected over the past 6 years, possibly related to waning of pre-existing HIV-specific CTL, and infection has often been associated with a switch in the epitope specificity of CD8+ responses. These findings suggest that vaccine-induced protective HIV immunity is a realistic goal, but that vaccine strategies of boosting or persistent antigen may be necessary for long-lived protection.

  15. Clonal dominance among T-lymphocyte infiltrates in arthritis

    SciTech Connect

    Stamenkovic, I.; Stegagno, M.; Wright, K.A.; Krane, S.M.; Amento, E.P.; Colvin, R.B.; Duquesnoy, R.J.; Kurnick, J.T.

    1988-02-01

    Synovial membranes in patients with rheumatoid arthritis as well as other types of chronic destructive inflammatory arthritis contain infiltrates of activated T lymphocytes that probably contribute to the pathogenesis of the disease. In an effort to elucidate the nature of these infiltrates, interleukin 2 (IL-2)-responsive T lymphocytes were grown out of synovial fragments from 14 patients undergoing surgery for advanced destructive inflammatory joint disease. Eleven of the samples examined were from patients with classical rheumatoid arthritis, while three others were obtained from individuals with clinical osteoarthritis. Southern blot analysis of T-cell receptor (TCR) ..beta..-chain genes in 13 of 14 cultures showed distinct rearrangements, indicating that each culture was characterized by the predominance of a limited number of clones. T-cell populations from peripheral blood stimulated with a variety of activators and expanded with IL-2 did not demonstrate evidence of similar clonality in long-term culture. These results suggest that a limited number of activated T-cell clones predominate at the site of tissue injury in rheumatoid synovial membranes as well as in other types of destructive inflammatory joint disease. Further characterization of these T-cell clones may aid our understanding of the pathogenesis of these rheumatic disorders.

  16. Cross-reactivity of sperm and T lymphocyte antigens.

    PubMed

    Mathur, S; Goust, J M; Williamson, H O; Fudenberg, H H

    1981-01-01

    Evidence is presented for cross-reactivity between antigens on human sperm and T lymphocytes. In 25 infertile couples in which both the males and females had significant antisperm immunity, antibody (Ab) titers to thymocytes (mean +/- S.E.M. 159 +/- 4 and 72 +/- 14, respectively, in males and females), T cell lines CCRF-CEM (69 +/- 5 and 48 +/- 8) and HSB-2 (56 +/- 15) and 41 +/- 8), suppressor-enriched (TG) cells (26 +/- 6 and 66 +/- 28) and helper-enriched (TG-) cells (26 +/- 4 and 46 +/- 14) were significantly elevated, as compared with Ab titers in 45 normal males and 45 normal females without antisperm immunity. Antibody titers to adult B cells, B cell line RAJI, and granulocytes were similar in the two groups. Antisperm Ab titers in sera, sperm extracts, and seminal plasma of the infertile subjects were significantly reduced after absorption with sperm, thymocytes, or T cell line CCRF-CEM but not with the B cell line RAJI. Antithymocyte Ab titers in the sera were significantly reduced (p less than 0.001) after absorption with thymocytes, CCRF-CEM, or sperm, but not RAJI. Lymphocytes from the infertile patients, when stimulated with pokeweed mitogen in vitro, produced antisperm and anti-T-lymphocyte antibodies at significantly higher titers than normal controls.

  17. Modulation of MUC1 mucin as an escape mechanism of breast cancer cells from autologous cytotoxic T-lymphocytes

    PubMed Central

    Kontani, K; Taguchi, O; Narita, T; Izawa, M; Hiraiwa, N; Zenita, K; Takeuchi, T; Murai, H; Miura, S; Kannagi, R

    2001-01-01

    MUC1 mucin is known to serve as a target molecule in the killing of breast cancer cells by cytotoxic T-lymphocytes (CTLs). We searched for a possible mechanism allowing tumour cells to escape from autologous CTLs. When the killing of breast cancer cells by autologous lymphocytes was examined in 26 patients with breast cancer, significant tumour cell lysis was observed in 8 patients, whereas virtually no autologous tumour cell lysis was detected in as many as 18 patients. In the patients who showed negligible tumour cell lysis, the autologous tumour cells expressed MUC1-related antigenic epitopes much more weakly than the tumour cells in the patients who exhibited strong cytotoxicity (significant statistically at P< 0.0005–0.0045), suggesting that the unresponsiveness of cancer cells to CTLs observed in these patients was mainly due to loss of MUC1 expression or modulation of its antigenicity. A breast cancer cell line, NZK-1, established from one of the cytotoxicity-negative patients, did not express MUC1 and was resistant to killing by CTLs, while control breast cancer cell lines expressing MUC-1 were readily killed by CTLs. Transfection of NZK-1 cells with MUC1 cDNA induced significant lysis by autologous T-lymphocytes. These results supported the importance of MUC1 mucin in autologous anti-tumour immunity, but suggested that the major escape mechanism of tumour cells from autologous T-lymphocytes is the loss and/or modulation of MUC1 antigenicity on tumour cells, which would limit the effectiveness of possible immunotherapy designed to target the MUC1 mucin. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11336479

  18. Cytotoxic T-lymphocyte-mediated killing of human pancreatic islet cells in vitro.

    PubMed

    Campbell, Peter D; Estella, Eugene; Dudek, Nadine L; Jhala, Gaurang; Thomas, Helen E; Kay, Thomas W H; Mannering, Stuart I

    2008-09-01

    Cytotoxic T lymphocytes (CTL) are believed to play an essential role in beta-cell destruction leading to development of type 1 diabetes and allogeneic islet graft failure. We aimed to identify the mechanisms used by CTL to kill human beta cells. CTL clones that recognize epitopes from influenza virus and Epstein-Barr virus restricted by human leukocyte antigen (HLA)-A0201 and -B0801, respectively, were used to investigate the susceptibility of human beta cells to CTL. In a short-term (5-hour) assay, CTL killed human islet cells of the appropriate major histocompatibility complex (MHC) class I type that had been pulsed with viral peptides. Killing was increased by pretreating islets with interferon gamma that increases MHC class I on target cells. Killing was abolished by incubation of CTL with the perforin inhibitor concanamycin A. The Fas pathway did not contribute to killing because blocking with neutralizing anti-Fas ligand antibody did not significantly reduce beta-cell killing. In conclusion, we report a novel way of investigating the interaction between CTL and human islets. Human islets were rapidly killed in vitro by MHC class I-restricted CTL predominantly by the granule exocytosis pathway.

  19. Heligmosomoides polygyrus immunomodulatory factor (IMF), targets T-lymphocytes.

    PubMed

    Telford, G; Wheeler, D J; Appleby, P; Bowen, J G; Pritchard, D I

    1998-12-01

    Experiments were performed to investigate the immunological site of action of an immunomodulatory factor (IMF), isolated from the gastrointestinal nematode Heligmosomoides polygyrus. IMF inhibited antibody production in murine and human 'T-helper (Th-2) driven' immunoassays. The effects were mediated via T lymphocytes as T cell-depleted cultures failed to respond to IMF, a result confirmed by prepulsing discrete cell subsets with the immunomodulant. Although the molecular nature and mode of action of IMF has yet to be determined, it would appear to be a relatively small non-proteinaceous molecule. From this data, we suggest that H. polygyrus secretes a systemically-active IMF from the intestinal lumen, to down-regulate Th-2 cell development in order to promote its survival in a potentially immunologically hostile environment.

  20. Pseudomonas aeruginosa exoenzyme S induces proliferation of human T lymphocytes.

    PubMed Central

    Mody, C H; Buser, D E; Syme, R M; Woods, D E

    1995-01-01

    Pseudomonas aeruginosa is a gram-negative bacterium that is responsible for devastating acute and chronic infections, which include bronchiectasis in cystic fibrosis, nosocomial pneumonia, and infection of burn wounds. Previous studies have demonstrated that these patients have impaired host responses, including cell-mediated immune responses, which are important in anti-Pseudomonas host defense. The P. aeruginosa exoproduct, exoenzyme S, has a number of characteristics which suggest that it might be important in cell-mediated immunity. To determine whether exoenzyme S activates lymphocytes to proliferate, peripheral blood mononuclear cells (PBMC) from normal volunteers were stimulated with purified exoenzyme S, and the lymphocyte response was assessed by measuring [3H]thymidine uptake and by counting the number of cells after various times in culture. Ninety-five percent of healthy adult donors had a lymphocyte response to exoenzyme S. The optimal lymphocyte response occurred on day 7, with 4 x 10(5) PBMC per microtiter well when cells were stimulated with 10 micrograms exoenzyme S per ml. [3H]thymidine uptake correlated with an increase in the number of mononuclear cells, indicating that proliferation occurred. In unseparated PBMC, T cells, and to a lesser extent B cells, proliferated. Purified T cells proliferated, while purified B cells proliferated only after the addition of irradiated T cells. Thus, T lymphocytes are necessary and sufficient for the proliferative response to exoenzyme S. We speculate that exoenzyme S from P. aeruginosa is important in T-lymphocyte-mediated host defense to P. aeruginosa. In strategies to enhance impaired cell-mediated immunity, exoenzyme S should be considered as a potential stimulant. PMID:7537248

  1. Differential targeting of viral components by CD4+ versus CD8+ T lymphocytes in dengue virus infection.

    PubMed

    Rivino, Laura; Kumaran, Emmanuelle A P; Jovanovic, Vojislav; Nadua, Karen; Teo, En Wei; Pang, Shyue Wei; Teo, Guo Hui; Gan, Victor Chih Hao; Lye, David C; Leo, Yee Sin; Hanson, Brendon J; Smith, Kenneth G C; Bertoletti, Antonio; Kemeny, David M; MacAry, Paul A

    2013-03-01

    Dengue virus (DENV) is the principal arthropod-borne viral pathogen afflicting human populations. While repertoires of antibodies to DENV have been linked to protection or enhanced infection, the role of T lymphocytes in these processes remains poorly defined. This study provides a comprehensive overview of CD4(+) and CD8(+) T cell epitope reactivities against the DENV 2 proteome in adult patients experiencing secondary DENV infection. Dengue virus-specific T cell responses directed against an overlapping 15mer peptide library spanning the DENV 2 proteome were analyzed ex vivo by enzyme-linked immunosorbent spot assay, and recognition of individual peptides was further characterized in specific T cell lines. Thirty novel T cell epitopes were identified, 9 of which are CD4(+) and 21 are CD8(+) T cell epitopes. We observe that whereas CD8(+) T cell epitopes preferentially target nonstructural proteins (NS3 and NS5), CD4(+) epitopes are skewed toward recognition of viral components that are also targeted by B lymphocytes (envelope, capsid, and NS1). Consistently, a large proportion of dengue virus-specific CD4(+) T cells have phenotypic characteristics of circulating follicular helper T cells (CXCR5 expression and production of interleukin-21 or gamma interferon), suggesting that they are interacting with B cells in vivo. This study shows that during a dengue virus infection, the protein targets of human CD4(+) and CD8(+) T cells are largely distinct, thus highlighting key differences in the immunodominance of DENV proteins for these two cell types. This has important implications for our understanding of how the two arms of the human adaptive immune system are differentially targeted and employed as part of our response to DENV infection.

  2. Identification and Characterization of Ovarian Carcinoma Peptide Epitopes Recognized by Cytotoxic T Lymphocytes

    DTIC Science & Technology

    2006-11-01

    restricted response from two of six different donors. The peptide sensitized targets for lysis at 1 to 20 nM, indicating that these CTL had receptors ...Immunoediting. Annu Rev Immunol 2004;22(1):329-60. 2. Lollini PL, Cavallo F, Nanni P, Forni G . Vaccines for tumour prevention. Nature Reviews...number? Curr Opin Immunol 2005;17(3):320-5. 6. Parmiani G , Castelli C, Rivoltini L, et al. Immunotherapy of melanoma. Semin Cancer Biol 2003;13(6

  3. Identification and Characterization of Ovarian Carcinoma Peptide Epitopes Recognized by Cylotoxic T Lymphocytes

    DTIC Science & Technology

    2008-11-01

    class II MHC -specific mAb, L243 (Appendix 1, Fig. 2 ). Most lines do not express class II MHC molecules, although low...it was first necessary to characterize the available patient material for class I MHC , TAG, FBP, and Her- 2 /neu expression as has now been done... Class I and II MHC expression The class I MHC genotype of each of the ovarian cancer lines was determined by PCR analysis (Table 2 ). Because

  4. Identification and Characterization of Ovarian Carcinoma Peptide Epitopes Recognized by Cytotoxic T Lymphocytes

    DTIC Science & Technology

    2007-11-01

    class II MHC molecules as determined by their ability to bind the class II MHC -specific mAb, L243 (Fig. 2 ). Most lines do not...express class II MHC molecules, although low expression was detected on CAOV-3, CAOV-4, OVCAR-3, SW626, and a subpopulation of ES- 2 . This indicates that...representative of a minimum of two independent experiments for each cell line. 22 Fig. 2 Class I and class II MHC

  5. T lymphocytes in the murine vaginal mucosa are phenotypically distinct from those in the periphery.

    PubMed Central

    Fidel, P L; Wolf, N A; KuKuruga, M A

    1996-01-01

    The results from both clinical studies of women with recurrent vulvovaginal candidiasis and a murine model of experimental vaginitis indicate that systemic cell-mediated immunity may not represent a dominant host defense mechanism against vaginal infections by Candida albicans. Recent experimental evidence indicates the presence of local vaginal immune reactivity against C. albicans. The present study was designed to examine T-lymphocyte subpopulations in the vaginal mucosae of naive CBA/J mice. Vaginal lymphocytes (VL) were isolated by collagenase digestion of whole vaginal tissues. Cell populations were identified by flow cytometry, and the results were compared with those for both lymph node cells (LNC) and peripheral blood lymphocytes (PBL). The results of flow cytometry showed that 45% +/- 10% of lymphocytes in the vaginal mucosa are CD3+ compared with 75% +/- 5% in LNC and 50% +/- 5% in PBL. The majority (85%) of CD3+ VL are CD4+ and express the alpha/beta T-cell receptor (TCR), similar to the results for LNC and PBL. In contrast to LNC and PBL, VL contain a significantly higher percentage (15 to 20%) of gamma/delta TCR+ cells, 80% or more of which appear to express CD4. In addition, while CD4-CD8 cell ratios in LNC and PBL were 3:1 and 6:1, respectively, only 1% of VL expressed CD8, resulting in a CD4-CD8 cell ratio of > 100:1. Finally, while LNC and PBL recognized two epitope-distinct (GK 1.5 and 2B6) anti-CD4 antibodies, VL recognized only 2B6 anti-CD4 antibodies. Further analysis of VL showed that Thy-1 cells, but not CD4 cells, were reduced after intravaginal injection of complement-fixing anti-Thy-1.2 and GK 1.5 anti-CD4 antibodies, respectively. Taken together, these data suggest that T lymphocytes in the vaginal mucosae of mice are phenotypically distinct from those in the periphery and that CD4+ VL have an uncharacteristic or atypical expression of the CD4 receptor. PMID:8751931

  6. Cytotoxic T lymphocytes established by seasonal human influenza cross-react against 2009 pandemic H1N1 influenza virus.

    PubMed

    Tu, Wenwei; Mao, Huawei; Zheng, Jian; Liu, Yinping; Chiu, Susan S; Qin, Gang; Chan, Ping-Lung; Lam, Kwok-Tai; Guan, Jing; Zhang, Lijuan; Guan, Yi; Yuen, Kwok-Yung; Peiris, J S Malik; Lau, Yu-Lung

    2010-07-01

    While few children and young adults have cross-protective antibodies to the pandemic H1N1 2009 (pdmH1N1) virus, the illness remains mild. The biological reasons for these epidemiological observations are unclear. In this study, we demonstrate that the bulk memory cytotoxic T lymphocytes (CTLs) established by seasonal influenza viruses from healthy individuals who have not been exposed to pdmH1N1 can directly lyse pdmH1N1-infected target cells and produce gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha). Using influenza A virus matrix protein 1 (M1(58-66)) epitope-specific CTLs isolated from healthy HLA-A2(+) individuals, we further found that M1(58-66) epitope-specific CTLs efficiently killed both M1(58-66) peptide-pulsed and pdmH1N1-infected target cells ex vivo. These M1(58-66)-specific CTLs showed an effector memory phenotype and expressed CXCR3 and CCR5 chemokine receptors. Of 94 influenza A virus CD8 T-cell epitopes obtained from the Immune Epitope Database (IEDB), 17 epitopes are conserved in pdmH1N1, and more than half of these conserved epitopes are derived from M1 protein. In addition, 65% (11/17) of these epitopes were 100% conserved in seasonal influenza vaccine H1N1 strains during the last 20 years. Importantly, seasonal influenza vaccination could expand the functional M1(58-66) epitope-specific CTLs in 20% (4/20) of HLA-A2(+) individuals. Our results indicated that memory CTLs established by seasonal influenza A viruses or vaccines had cross-reactivity against pdmH1N1. These might explain, at least in part, the unexpected mild pdmH1N1 illness in the community and also might provide some valuable insights for the future design of broadly protective vaccines to prevent influenza, especially pandemic influenza.

  7. Membrane Surface Nanostructures and Adhesion Property of T Lymphocytes Exploited by AFM

    NASA Astrophysics Data System (ADS)

    Wu, Yangzhe; Lu, Hongsong; Cai, Jiye; He, Xianhui; Hu, Yi; Zhao, Hongxia; Wang, Xiaoping

    2009-08-01

    The activation of T lymphocytes plays a very important role in T-cell-mediated immune response. Though there are many related literatures, the changes of membrane surface nanostructures and adhesion property of T lymphocytes at different activation stages have not been reported yet. However, these investigations will help us further understand the biophysical and immunologic function of T lymphocytes in the context of activation. In the present study, the membrane architectures of peripheral blood T lymphocytes were obtained by AFM, and adhesion force of the cell membrane were measured by acquiring force-distance curves. The results indicated that the cell volume increased with the increases of activation time, whereas membrane surface adhesion force decreased, even though the local stiffness for resting and activated cells is similar. The results provided complementary and important data to further understand the variation of biophysical properties of T lymphocytes in the context of in vitro activation.

  8. Atopic dermatitis: serum immunoglobulins and T-lymphocyte subpopulations.

    PubMed

    Valdés Sánchez, A F; Gómez Echevarría, A H; Lastra Alfonso, G

    1991-04-01

    A group of patients with atopic dermatitis who attended the Allergy Outpatient Service of the Hermanos Ameijeiras Clinical Surgical Hospital from May, 1987 to May, 1988 were studied. The patients were assigned to 2 groups; the first one composed of 38 patients and the second one composed of 12 non-allergic, supposedly healthy subjects. Different tests were carried out for the quantification of total serum immunoglobulins (A, G, M, E) by means of the radial immunodiffusion method and the ELISA ultramicromethod. They were also submitted to quantification of lymphocyte subpopulations by means of the indirect immunofluorescence test with monoclonal antibodies, using Cuban antiserum prepared at the National Institute of Oncology and Radiobiology. In our study IgG and IgA values were within normal limits in patients, contrary to the statistically significant increase in IgM and IgE values. The relative values of total T-lymphocytes (anti-T3) and of the suppressor lymphocyte subpopulations decreased.

  9. T lymphocyte roles during Eimeria acervulina and Eimeria tenella infections.

    PubMed

    Trout, J M; Lillehoj, H S

    1996-09-01

    This study evaluated the effects of selective depletion of T lymphocytes on Eimeria infections in chickens. Cell depletions were initiated in day- or week-old Hyline SC strain chickens using intra-peritoneal injections of monoclonal antibodies to CD4, CD8, or T cell receptor (TCR) alpha/beta. Control chickens received injections of irrelevant monoclonal antibody or phosphate buffered saline (PBS). Following the establishment of cell depletion, chickens were infected orally with E. acervulina or E. tenella, 1 x 10(4) oocysts for primary infections and 2 x 10(5) oocysts for secondary infections. Chickens treated with anti CD4 monoclonal antibody produced significantly more oocysts than controls following primary E. tenella but not E. acervulina infections. Development of resistance to challenge infection was unaffected. These results suggest that CD4+ lymphocytes are important in controlling primary infection with E. tenella. Chickens treated with anti-CD8 or anti-TCR alpha/beta monoclonal antibodies produced significantly fewer oocysts than controls following primary infection but significantly more oocysts than controls following secondary infection with both E. tenella and E. acervulina. Additionally, anti-CD8 treatment abrogated resistance to challenge infection. CD8-depleted chickens may exhibit decreased oocyst production following primary infection due to a lack of CD8+ lymphocytes to serve as transporting cells for sporozoites. The abrogation of resistance to secondary infection in CD8- and TCR alpha/beta-depleted chickens suggests that these cells are necessary for the development of protective immunity to coccidia.

  10. Antigen receptor-regulated exocytosis in cytotoxic T lymphocytes

    PubMed Central

    1987-01-01

    We demonstrate here that T cell receptor for antigen (TCR)-triggered exocytosis in cytotoxic T lymphocytes (CTL) is not constitutive and is regulated through crosslinking of the TCR by antigen or monoclonal anti- TCR antibodies. Morphological and biochemical data using three different biochemical markers of granules and Percoll gradient fractionation analysis are presented, suggesting that TCR-triggered exocytosis is accompanied by the loss of granules from CTL and appearance of intragranular proteins and enzymatic activities in the incubation medium. The strict requirement for crosslinking of the TCR in exocytosis triggering could be bypassed by protein kinase C activators (phorbol esters or bryostatin I and II) acting in synergy with Ca2+ ionophores. It is shown that external Ca2+ is obligatory for both the TCR-triggered and for the PMA/A23187-triggered exocytosis, since Ca2+ chelators and divalent cations that compete with Ca2+ for A23187 can inhibit exocytosis of granules. These data suggest that Ca2+ from intracellular stores is not sufficient to support exocytosis in CTL. Ca2+ channel blockers and calmodulin antagonists significantly inhibited TCR-triggered exocytosis without affecting the basal level of secretion. The described results are consistent with a model in which exocytosis of granules in CTL is triggered by the crosslinking of TCR, transmembrane protein kinase C activation, and external Ca2+ translocation through CTL plasma membrane Ca2+ channels and modulation of activity of Ca2+, calmodulin-dependent enzymes, and cytoskeletal proteins. PMID:2442289

  11. Morphometric analysis of T lymphocyte compartmentation in experimental autoimmune uveoretinitis.

    PubMed Central

    Brown, E C; Kasp, E; Dumonde, D C

    1989-01-01

    Experimental autoimmune uveoretinitis (EAU) in the Lewis rat is characterized by extensive infiltration of inflammatory cells into all compartments of the eye, only some of which become irreversibly damaged. The apparent differences in the pathogenic impact of inflammatory cells within different ocular compartments may suggest that different mechanisms underlie cellular infiltration and selective tissue destruction. In order to investigate the importance of T lymphocyte infiltration, we carried out a precise topographical and temporal analysis of T cell infiltration into five compartments of the eye using an improved method for the fixation of ocular tissue. Our study showed that T cell infiltration began in the ciliary body and was most numerous and sustained in this area during EAU. The peak of T cell infiltration into the retina was comparatively delayed and was of lesser magnitude. Analysis of T cell subsets revealed a tendency for the helper phenotype to predominant during the course of disease in all ocular compartments except the retina where both helper and cytotoxic/suppressor T cells were equally represented at the height of inflammation. We suggest that the pathogenetic impact of autoreactive lymphocytes in EAU depends on the accessibility of relevant tissue antigen and on local microenvironmental features of lymphocytic traffic within different ocular compartments. Images Fig. 1 Fig. 2 PMID:2805411

  12. Protective Role of Cytotoxic T Lymphocytes in Filovirus Hemorrhagic Fever

    PubMed Central

    Warfield, Kelly Lyn; Olinger, Gene Garrard

    2011-01-01

    Infection with many emerging viruses, such as the hemorrhagic fever disease caused by the filoviruses, Marburg (MARV), and Ebola virus (EBOV), leaves the host with a short timeframe in which to mouse a protective immune response. In lethal cases, uncontrolled viral replication and virus-induced immune dysregulation are too severe to overcome, and mortality is generally associated with a lack of notable immune responses. Vaccination studies in animals have demonstrated an association of IgG and neutralizing antibody responses against the protective glycoprotein antigen with survival from lethal challenge. More recently, studies in animal models of filovirus hemorrhagic fever have established that induction of a strong filovirus-specific cytotoxic T lymphocyte (CTL) response can facilitate complete viral clearance. In this review, we describe assays used to discover CTL responses after vaccination or live filovirus infection in both animal models and human clinical trials. Unfortunately, little data regarding CTL responses have been collected from infected human survivors, primarily due to the low frequency of disease and the inability to perform these studies in the field. Advancements in assays and technologies may allow these studies to occur during future outbreaks. PMID:22253531

  13. Mitogenic signal transduction in T lymphocytes in microgravity

    NASA Technical Reports Server (NTRS)

    Cogoli, A.; Bechler, B.; Cogoli-Greuter, M.; Criswell, S. B.; Joller, H.; Joller, P.; Hunzinger, E.; Muller, O.

    1993-01-01

    The activation by concanavalin A Con A of human peripheral blood lymphocytes (PBLs) in the presence of monocytes as accessory cells was investigated in cultures exposed to microgravity conditions in Spacelab. Activation of T cells was measured as incorporation of [3H]thymidine into DNA, secretion of interleukin-2 (IL-2), and interferon-gamma, and expression of IL-2 receptors. Whereas, as discovered in earlier experiments, the activation of resuspended T cells is strongly inhibited, activation of cells attached to microcarrier beads is more than doubled in microgravity. The results suggest that the depression of the activation in resuspended cells may be attributed to a malfunction of monocytes acting as accessory cells. In fact, although the ultrastructure of resuspended monocytes is not altered in microgravity, the secretion of IL-1 is strongly inhibited. Our data suggest that (1) IL-2 is produced independently of IL-1, (2) IL-1 production is triggered only when monocytes (and lymphocytes?) adhere to microcarriers, (3) the expression of IL-2 receptors depends on IL-1, and (4) provided sufficient IL-1 is available, activation is enhanced in microgravity. Finally, cultures of resuspended PBLs and monocytes in microgravity constitute a complete and natural system in which monocytes are not operational. This may be useful for studies of the role of accessory cells and cell-cell interactions in T lymphocyte activation.

  14. Specific binding of antigen onto human T lymphocytes

    SciTech Connect

    Durandy, A.; Fischer, A.; Charron, D.; Griscelli, C.

    1986-05-01

    Human T lymphocytes sensitized to Candida albicans (CA) were shown to proliferate in cultures induced with mannan, a ramified polysaccharide extracted from the cell well of CA. We presently describe that, when we used strongly labeled (/sup 3/H)mannan, antigen-specific T blast cells were able to bind the labeled mannan on their membrane. The observations that irrelevant blast cells did not bind (/sup 3/H)mannan, and that mannan-specific blast cells did not bind tritiated pneumococcal polysaccharide SIII, indicate the specificity of mannan binding. Mannan binding was reversible and saturable. Mannan binding on T blast cells was inhibited by preincubation with monoclonal antibodies to T3 but not to other T cell-related molecules. The characteristics of this receptor suggest its identity with the T cell receptor for antigen. The direct binding of mannan could be either due to a cross-linking of the receptor by multivalent mannan or to a recognition of mannan in association with HLA-DQ molecules, as suggested by partial blocking of mannan binding using anti-HLA-DQ monoclonal antibodies.

  15. Functional aortic stiffness: role of CD4(+) T lymphocytes.

    PubMed

    Majeed, Beenish A; Eberson, Lance S; Tawinwung, Supannikar; Larmonier, Nicolas; Secomb, Timothy W; Larson, Douglas F

    2015-01-01

    The immune system is suggested to be essential in vascular remodeling and stiffening. To study the dependence upon lymphocytes in vascular stiffening, we compared an angiotensin II-model of vascular stiffening in normal C57BL/6J mice with lymphocyte-deficient RAG 1(-/-) mice and additionally characterized the component of vascular stiffness due to vasoconstriction vs. vascular remodeling. Chronic angiotensin II increased aortic pulse wave velocity, effective wall stiffness, and effective Young's modulus in C57BL/6J mice by three-fold but caused no change in the RAG 1(-/-) mice. These functional measurements were supported by aortic morphometric analysis. Adoptive transfer of CD4(+) T helper lymphocytes restored the angiotensin II-mediated aortic stiffening in the RAG 1(-/-) mice. In order to account for the hydraulic vs. material effects of angiotensin II on pulse wave velocity, subcutaneous osmotic pumps were removed after 21 days of angiotensin II-infusion in the WT mice to achieve normotensive values. The pulse wave velocity (PWV) decreased from three- to two-fold above baseline values up to 7 days following pump removal. This study supports the pivotal role of the CD4(+) T-lymphocytes in angiotensin II-mediated vascular stiffening and that angiotensin II-mediated aortic stiffening is due to the additive effect of active vascular smooth muscle vasoconstriction and vascular remodeling.

  16. Divalent ion trapping inside potassium channels of human T lymphocytes

    PubMed Central

    1989-01-01

    Using the patch-clamp whole-cell recording technique, we investigated the influence of external Ca2+, Ba2+, K+, Rb+, and internal Ca2+ on the rate of K+ channel inactivation in the human T lymphocyte-derived cell line, Jurkat E6-1. Raising external Ca2+ or Ba2+, or reducing external K+, accelerated the rate of the K+ current decay during a depolarizing voltage pulse. External Ba2+ also produced a use-dependent block of the K+ channels by entering the open channel and becoming trapped inside. Raising internal Ca2+ accelerated inactivation at lower concentrations than external Ca2+, but increasing the Ca2+ buffering with BAPTA did not affect inactivation. Raising [K+]o or adding Rb+ slowed inactivation by competing with divalent ions. External Rb+ also produced a use-dependent removal of block of K+ channels loaded with Ba2+ or Ca2+. From the removal of this block we found that under normal conditions approximately 25% of the channels were loaded with Ca2+, whereas under conditions with 10 microM internal Ca2+ the proportion of channels loaded with Ca2+ increased to approximately 50%. Removing all the divalent cations from the external and internal solution resulted in the induction of a non-selective, voltage-independent conductance. We conclude that Ca2+ ions from the outside or the inside can bind to a site at the K+ channel and thereby block the channel or accelerate inactivation. PMID:2786551

  17. Physiological changes induced in cardiac myocytes by cytotoxic T lymphocytes

    SciTech Connect

    Hassin, D.; Fixler, R.; Shimoni, Y.; Rubinstein, E.; Raz, S.; Gotsman, M.S.; Hasin, Y.

    1987-01-01

    The lethal hit induced by viral specific, sensitized, cytotoxic T lymphocytes (CTL) attacking virus-infected heart cells is important in the pathogenesis of viral myocarditis and reflects the key role of CTL in this immune response. The mechanisms involved are incompletely understood. Studies of the physiological changes induced in mengovirus-infected, cultured, neonatal, rat heart cells by CTL that had been previously sensitized by the same virus are presented. The CTL were obtained from spleens of mengovirus-infected, major histocompatibility complex (MHC) matched adult rats. Cell wall motion was measured by an optical method, action potentials with intracellular microelectrodes, and total exchangeable calcium content by /sup 45/Ca tracer measurements after loading the myocytes with /sup 45/Ca and then exposing them to CTL. After 50 min (mean time) of exposing mengovirus-infected myocytes to the CTL, the mechanical relaxation of the myocyte was slowed, with a subsequent slowing of beating rate and a reduced amplitude of contraction. Impaired relaxation progressed, and prolonged oscillatory contractions lasting up to several seconds appeared, with accompanying oscillations in the prolonged plateau phase of the action potentials. Arrest of the myocyte contractions appeared 98 min (mean time) after exposure to CTL. It is concluded that infection of cultured myocytes with mengovirus predisposes them to attack by mengovirus specific CTL, and that persistent dysfunction of the myocyte is preceded by reversible changes in membrane potential and contraction. This is suggestive of an altered calcium handling by the myocytes possibly resulting in the cytotoxic effect.

  18. Boosting antitumor responses of T lymphocytes infiltrating human prostate cancers.

    PubMed

    Bronte, Vincenzo; Kasic, Tihana; Gri, Giorgia; Gallana, Keti; Borsellino, Giovanna; Marigo, Ilaria; Battistini, Luca; Iafrate, Massimo; Prayer-Galetti, Tommaso; Pagano, Francesco; Viola, Antonella

    2005-04-18

    Immunotherapy may provide valid alternative therapy for patients with hormone-refractory metastatic prostate cancer. However, if the tumor environment exerts a suppressive action on antigen-specific tumor-infiltrating lymphocytes (TIL), immunotherapy will achieve little, if any, success. In this study, we analyzed the modulation of TIL responses by the tumor environment using collagen gel matrix-supported organ cultures of human prostate carcinomas. Our results indicate that human prostatic adenocarcinomas are infiltrated by terminally differentiated cytotoxic T lymphocytes that are, however, in an unresponsive status. We demonstrate the presence of high levels of nitrotyrosines in prostatic TIL, suggesting a local production of peroxynitrites. By inhibiting the activity of arginase and nitric oxide synthase, key enzymes of L-arginine metabolism that are highly expressed in malignant but not in normal prostates, reduced tyrosine nitration and restoration of TIL responsiveness to tumor were achieved. The metabolic control exerted by the tumor on TIL function was confirmed in a transgenic mouse prostate model, which exhibits similarities with human prostate cancer. These results identify a novel and dominant mechanism by which cancers induce immunosuppression in situ and suggest novel strategies for tumor immunotherapy.

  19. Allorestricted T lymphocytes with a high avidity T-cell receptor towards NY-ESO-1 have potent anti-tumor activity.

    PubMed

    Krönig, Holger; Hofer, Kathrin; Conrad, Heinke; Guilaume, Philippe; Müller, Julia; Schiemann, Matthias; Lennerz, Volker; Cosma, Antonio; Peschel, Christian; Busch, Dirk H; Romero, Pedro; Bernhard, Helga

    2009-08-01

    The cancer-testis antigen NY-ESO-1 has been targeted as a tumor-associated antigen by immunotherapeutical strategies, such as cancer vaccines. The prerequisite for a T-cell-based therapy is the induction of T cells capable of recognizing the NY-ESO-1-expressing tumor cells. In this study, we generated human T lymphocytes directed against the immunodominant NY-ESO-1(157-165) epitope known to be naturally presented with HLA-A*0201. We succeeded to isolate autorestricted and allorestricted T lymphocytes with low, intermediate or high avidity TCRs against the NY-ESO-1 peptide. The avidity of the established CTL populations correlated with their capacity of lysing HLA-A2-positive, NY-ESO-1-expressing tumor cell lines derived from different origins, e.g. melanoma and myeloma. The allorestricted NY-ESO-1-specific T lymphocytes displayed TCRs with the highest avidity and best anti-tumor recognition activity. TCRs derived from allorestricted, NY-ESO-1-specific T cells may be useful reagents for redirecting primary T cells by TCR gene transfer and, therefore, may facilitate the development of adoptive transfer regimens based on TCR-transduced T cells for the treatment of NY-ESO-1-expressing hematological malignancies and solid tumors.

  20. Transformation of T-lymphocyte subsets by Marek's disease herpesvirus.

    PubMed Central

    Schat, K A; Chen, C L; Calnek, B W; Char, D

    1991-01-01

    Marek's disease herpesvirus (MDV)-transformed lymphoblastoid tumor cell lines were characterized for the presence of the surface markers. Monoclonal antibodies were used for CD3 (T-cell receptor [TCR] complex), TCR1, TCR2, and TCR3, CD4, CD8, and Ia antigen by indirect fluorescence staining followed by microscopic examination or flow cytometry. The lymphoblastoid cell lines were obtained from tumors from chickens infected with MDV (n = 44) or from local lesions induced by inoculation of allogeneic, MDV-infected chick kidney cells (n = 56). Lymphocytes were harvested from these lesions between 4 and 16 days postinoculation and cultured in vitro to establish cell lines. All cell lines expressed Ia antigen and CD3 and/or TCR and thus are activated T cells. Most of the cell lines developed from tumors were CD4+ CD8-; only one cell line was negative for both markers. Sixteen percent of the cell lines were TCR3+, while the remainder were TCR2+. The cell lines developed from local lesions were much more heterogeneous: 45% were CD4- CD8+, 34% were CD4- CD8-, and only 21% were CD4+ CD8-. The number of TCR3+ cell lines was larger than expected for the CD4- CD8+ and CD4- CD8- cell lines, as judged from the presence of these cells in the blood. These results indicate that several subsets of T lymphocytes can be transformed by MDV, depending on the pathogenesis of infection. Activation of T cells as a consequence of the normal pathogenesis or by allogeneic stimulation seem to be a first important step in the process of transformation. PMID:1847460

  1. Antigen heterogeneity of human B and T lymphocytes.

    PubMed Central

    Rabellino, E M; Grey, H M; LaForge, S; Pirofsky, B; Kashiwagi, N; Malley, A

    1976-01-01

    Rhesus monkeys were immunized with normal human lymphoid cells, cultured lymphoid cells, and chronic leukemic lymphocytes. Antisera were analyzed by cytotoxicity and immunofluorescence techniques to study the antigenic characteristics of human lymphocytes. In an attempt to obtain a reagent specifically reactive with T (thymus-derived) lymphocytes, an antispleen antiserum was absorbed with cellf from five B- (bone marrow-derived) cell lines. After absorption, the antiserum killed 60-75% of peripheral blood lymphocytes and 40-50% of tonsil cells, so that there was a relationship between the percentage of killed cells and the proportion of T lymphocytes. However, when cells after cytotoxic treatment were assayed for rosette formation with sheep erythrocytes (a T-cell marker) 5-20% of viable rosette-forming lymphocytes were found. Therefore, this antiserum was cytotoxic for only 75-90% of T cells. From studies performed with antisera prepared against spleen and B-cell lines, we conclude that lymphoblastoid cells are antigenically different and deficient in comparison to normal B lymphocytes. In addition, cultured B-cell lines appear to be antigenically heterogenous, as shown by the cytotoxic activity remaining in antispleen and anti-B-cell lines sera after absorption with various numbers and types of lymphoid cell lines. After absorption with normal lymphocytes, an antiserum produced against chronic lymphatic leukemia cells had specific activity associated with 12 chronic lymphatic leukemia cells tested. Absorption of the same antiserum with leukemic cells from two patients showed that a certain degree of antigenic heterogeneity also exists among chronic leukemic lymphocytes. PMID:815274

  2. The case for extrathymic development of vaginal T lymphocytes.

    PubMed

    Hamad, Mawieh

    2008-04-01

    The vaginal tract mucosa is populated by a small, yet phenotypically diverse and functionally significant, subset of T cells that plays a major role in local cell-mediated immunity. Although phenotypic and functional characteristics of vaginal T cells have received some attention in recent years, little is known about the development of this cell population. In this mini review, the developmental origins of vaginal T cells are traced from published work related to vaginal T cells, the vaginal mucosa environment and vaginal tract infection animal models. A CD3(+)TCR(+)CD2(+)CD5(+)B220(-) (CD3(+)B220(-)) subpopulation, which is mostly CD4(+), makes up 30-40% of vaginal T lymphocytes. This population consists of a TCRalphabeta(+) subset and TCRgammadelta(+) subset. While CD3(+)B220(-)TCRalphabeta(+) vaginal T cells exhibit phenotypic and functional properties consistent with that of peripheral T cells, CD3(+)B220(-)TCRgammadelta(+) vaginal T cells exhibit unique phenotypic and functional features that set them apart from other TCRgammadelta(+) T cell subsets populating the periphery or other mucosal areas. The vaginal mucosa is populated also by CD3(+)TCRalphabeta(+)CD4(-)/8(-)B220(+)CD2(-)CD5(-) T cells (CD3(+)B220(+)) whose relative predominance increases significantly in systemic T cell deficiency. This subset is generally unresponsive to TCR-mediated stimuli and expresses high levels of CD25, perhaps indicative of a regulatory role. Current data suggest that, while CD3(+)B220(-) vaginal T cells are mostly thymic in origin, CD3(+)TCRalphabeta(+)B220(+) cells are exclusively extrathymic.

  3. Forging T-Lymphocyte Identity: Intersecting Networks of Transcriptional Control

    PubMed Central

    Rothenberg, Ellen V.; Ungerbäck, Jonas; Champhekar, Ameya

    2016-01-01

    T lymphocyte development branches off from other lymphoid developmental programs through its requirement for sustained environmental signals through the Notch pathway. In the thymus, Notch signaling induces a succession of T-lineage regulatory factors that collectively create the T-cell identity through distinct steps. This process involves both the staged activation of T-cell identity genes and the staged repression of progenitor-cell-inherited regulatory genes once their roles in self-renewal and population expansion are no longer needed. With the recent characterization of Innate Lymphoid Cells (ILCs) that share transcriptional regulation programs extensively with T cell subsets, T-cell identity can increasingly be seen as defined in modular terms, as the processes selecting and actuating effector function are potentially detachable from the processes generating and selecting clonally unique T-cell receptor structures. The developmental pathways of different classes of T cells and ILCs are distinguished by the numbers of prerequisites of gene rearrangement, selection, and antigen contact before the cells gain access to nearly-common regulatory mechanisms for choosing effector function. Here, the major classes of transcription factors that interact with Notch signals during T-lineage specification are discussed in terms of their roles in these programs, the evidence for their spectra of target genes at different stages, and their cross-regulatory and cooperative actions with each other. Specific topics include Notch modulation of PU.1 and GATA-3, PU.1-Notch competition, the relationship between PU.1 and GATA-3, and the roles of E proteins, Bcl11b, and GATA-3 in guiding acquisition of T-cell identity while avoiding redirection to an ILC fate. PMID:26791859

  4. Sustained Dysfunction of Antiviral CD8+ T Lymphocytes after Infection with Hepatitis C Virus

    PubMed Central

    Gruener, Norbert H.; Lechner, Franziska; Jung, Maria-Christina; Diepolder, Helmut; Gerlach, Tilman; Lauer, Georg; Walker, Bruce; Sullivan, John; Phillips, Rodney; Pape, Gerd R.; Klenerman, Paul

    2001-01-01

    Hepatitis C virus (HCV) sets up persistent infection in the majority of those exposed. It is likely that, as with other persistent viral infections, the efficacy of T-lymphocyte responses influences long-term outcome. However, little is known about the functional capacity of HCV-specific T-lymphocyte responses induced after acute infection. We investigated this by using major histocompatibility complex class I-peptide tetrameric complexes (tetramers), which allow direct detection of specific CD8+ T lymphocytes ex vivo, independently of function. Here we show that, early after infection, virus-specific CD8+ T lymphocytes detected with a panel of four such tetramers are abnormal in terms of their synthesis of antiviral cytokines and lytic activity. Furthermore, this phenotype is commonly maintained long term, since large sustained populations of HCV-specific CD8+ T lymphocytes were identified, which consistently had very poor antiviral cytokine responses as measured in vitro. Overall, HCV-specific CD8+ T lymphocytes show reduced synthesis of tumor necrosis factor alpha (TNF-α) and gamma interferon (IFN-γ) after stimulation with either mitogens or peptides, compared to responses to Epstein-Barr virus and/or cytomegalovirus. This behavior of antiviral CD8+ T lymphocytes induced after HCV infection may contribute to viral persistence through failure to effectively suppress viral replication. PMID:11356962

  5. Changes in T-lymphocytes' viability after laparoscopic versus open cholecystectomy.

    PubMed

    Gomatos, Ilias P; Alevizos, Leonidas; Kalathaki, Olga; Kantsos, Harilaos; Kataki, Agapi; Leandros, Emmanuel; Zografos, George; Konstantoulakis, Manousos

    2015-04-01

    Laparoscopic surgery results in decreased immune and metabolic stress response compared to open surgery. Our aim was to evaluate the suspension of host immune defense in terms of apoptosis, necrosis, and survival of peripheral T-lymphocytes in patients undergoing laparoscopic versus open cholecystectomy. Apoptosis, necrosis and viability of peripheral T-lymphocytes were measured preoperatively and postoperatively by means of flow cytometry in 27 patients undergoing laparoscopic cholecystectomy and 25 undergoing open cholecystectomy. White cell count, CRP, and serum glucose levels were also measured. Viable peripheral T-lymphocytes were significantly decreased in open cholecystectomy (P = 0.02), while their late apoptotic as well as the overall necrotic rate were significantly increased (P = 0.01 and P < 0.01, respectively). Open cholecystectomy was also associated with lower levels of surviving circulating T-lymphocytes (P = 0.01) and higher percentage of necrotic T lymphocytes (P = 0.03) 24 hours postoperatively compared to laparoscopic cholecystectomy. Serum CRP was increased 24 hours after open cholecystectomy (P = 0.04). All differences failed to sustain more than 48 hours postoperatively. Increased viability and decreased necrosis of circulating T-lymphocytes were observed in laparoscopic cholecystectomy. Necrosis (and not apoptosis) seems to be the predominant pathway of T-lymphocyte death in open cholecystectomy, in a process reaching its peak at 24 hours and further attenuating 48 hours postoperatively.

  6. T lymphocyte line specific for thyroglobulin produces or vaccinates against autoimmune thyroiditis in mice.

    PubMed

    Maron, R; Zerubavel, R; Friedman, A; Cohen, I R

    1983-11-01

    We investigated Ly-1+ T lymphocyte line cells specifically reactive to thyroglobulin (Tg) that were isolated from mice primed with mouse Tg in adjuvant. Intravenous inoculation of as few as 10(5) line cells was sufficient to cause severe and prolonged thyroiditis in recipient mice that were intact, irradiated, or athymic nudes. Disease was independent of circulating Tg antibodies, suggesting that anti-Tg T lymphocytes could cause thyroiditis unaided by antibodies. Thyroiditogenic T lymphocytes could be isolated as cell lines from apparently healthy mice that had been immunized with non-thyroiditogenic bovine Tg in adjuvant, which indicates that autoimmune effector T lymphocytes may develop covertly in the course of immunization with foreign antigens. Finally, a single i.v. inoculation of anti-Tg T lymphocyte line cells attenuated by irradiation vaccinated mice completely against subsequent development of autoimmune thyroiditis produced either by active immunization to Tg or by passive transfer of intact line cells. Vaccinated mice that were protected from inflammatory lesions of thyroiditis still produced high titers of Tg antibodies in response to active immunization. Thus, vaccination specifically inhibited thyroiditogenic T lymphocytes but not helper T lymphocytes required for the production of Tg autoantibodies.

  7. A subset of memory CD4+ helper T lymphocytes identified by expression of Pgp-1

    PubMed Central

    1989-01-01

    The Pgp-1 glycoprotein (Ly-24 antigen) is acquired by mature murine T lymphocytes at the time of primary antigen stimulation Pgp-1 was previously shown to be a useful cell surface marker for distinguishing antigen-specific memory CD8+ T lymphocytes after immunization. Here we demonstrate that this observation extends to CD4+ T lymphocytes. Antigen-specific CD4+ T cells in mice immunized with sperm whale myoglobin or keyhole limpet hemocyanin were contained nearly exclusively in the minor Pgp-1+ subset. PMID:2564418

  8. Novel plant virus-based vaccine induces protective cytotoxic T-lymphocyte-mediated antiviral immunity through dendritic cell maturation.

    PubMed

    Lacasse, Patrick; Denis, Jérôme; Lapointe, Réjean; Leclerc, Denis; Lamarre, Alain

    2008-01-01

    Currently used vaccines protect mainly through the production of neutralizing antibodies. However, antibodies confer little or no protection for a majority of chronic viral infections that require active involvement of cytotoxic T lymphocytes (CTLs). Virus-like particles (VLPs) have been shown to be efficient inducers of cell-mediated immune responses, but administration of an adjuvant is generally required. We recently reported the generation of a novel VLP system exploiting the self-assembly property of the papaya mosaic virus (PapMV) coat protein. We show here that uptake of PapMV-like particles by murine splenic dendritic cells (DCs) in vivo leads to their maturation, suggesting that they possess intrinsic adjuvant-like properties. DCs pulsed with PapMV-like particles displaying the lymphocytic choriomeningitis virus (LCMV) p33 immunodominant CTL epitope (PapMV-p33) efficiently process and cross-present the viral epitope to p33-specific transgenic T cells. Importantly, the CTL epitope is also properly processed and presented in vivo, since immunization of p33-specific T-cell receptor transgenic mice with PapMV-p33 induces the activation of large numbers of specific CTLs. C57BL/6 mice immunized with PapMV-p33 VLPs in the absence of adjuvant develop p33-specific effector CTLs that rapidly expand following LCMV challenge and protect vaccinated mice against LCMV infection in a dose-dependent manner. These results demonstrate the efficiency of this novel plant virus-based vaccination platform in inducing DC maturation leading to protective CTL responses.

  9. Antibodies Against Membrane Interleukin 1α Activate Accessory Cells to Stimulate Proliferation of T Lymphocytes

    NASA Astrophysics Data System (ADS)

    Eugui, Elsie M.; Almquist, Susan J.

    1990-02-01

    Some monoclonal antibodies (mAbs) against interleukin (IL) 1α have been found to activate antigen-presenting cells (APC, human peripheral blood monocytes and B lymphocytes), so that unstimulated T lymphocytes cultured with them are induced to proliferate and secrete IL-2. Control mAbs of the same isotypes and mAbs against IL-11β do not activate APC. In the absence of APC, mAbs against IL-1α do not induce proliferation of T lymphocytes. Mitomycin C-treated activated APC still induce T-cell proliferation. Proliferation of T lymphocytes cannot be induced by culture supernatants and requires contact with APC activated by mAbs against IL-1α. The observations imply that surface membrane IL-1α can function as a triggering molecule on APC, which could play an important role in the initiation of immune responses by T lymphocytes.

  10. [Helper or suppressor activity of T lymphocytes in patients with Berger's disease].

    PubMed

    Biagi, R; Beltrandi, E; Rossi, L; Cagnoli, L; Fiorentini, G P

    1983-09-30

    We have studied the immunological aspects in ten cases of Berger disease. Interaction between B and T lymphocytes were investigated to define help or suppressor activity 6 cases have demonstrated help activity, while suppressor activity was observed in two cases.

  11. Products from mast cells influence T lymphocyte proliferation and cytokine production--relevant to allergic asthma?

    PubMed

    de Pater-Huijsen, F L; Pompen, M; Jansen, H M; Out, T A

    1997-06-01

    In IgE allergic diseases both mast cells and T lymphocytes play an important role. Whereas mast cels have been implicated in immediate allergic responses, T lymphocytes mediate subsequent late phase responses and chronic inflammation. Here we review possible links between the early mast cell activation and the later T lymphocyte stimulation. Products from mast cells were found to exert effects on T lymphocytes. Human Mast Cell line-1 (HMC-1) mast cells modulated proliferation and cytokine production of a human CD8+ T-cell clone in vitro. Activated mast cells seemed to drive this CD8+ T-cell clone towards a more pronounced T (helper) 1 type of response, simultaneously decreasing T-cell numbers. It is hypothesized that this might be a negative feed back mechanism operating in allergic subjects, by which the Th2-driven IgE production and eosinophilia are counteracted.

  12. Selection, Transmission, and Reversion of an Antigen-Processing Cytotoxic T-Lymphocyte Escape Mutation in Human Immunodeficiency Virus Type 1 Infection

    PubMed Central

    Allen, Todd M.; Altfeld, Marcus; Yu, Xu G.; O'Sullivan, Kristin M.; Lichterfeld, Mathias; Le Gall, Sylvie; John, Mina; Mothe, Bianca R.; Lee, Paul K.; Kalife, Elizabeth T.; Cohen, Daniel E.; Freedberg, Kenneth A.; Strick, Daryld A.; Johnston, Mary N.; Sette, Alessandro; Rosenberg, Eric S.; Mallal, Simon A.; Goulder, Philip J. R.; Brander, Christian; Walker, Bruce D.

    2004-01-01

    Numerous studies now support that human immunodeficiency virus type 1 (HIV-1) evolution is influenced by immune selection pressure, with population studies showing an association between specific HLA alleles and mutations within defined cytotoxic T-lymphocyte epitopes. Here we combine sequence data and functional studies of CD8 T-cell responses to demonstrate that allele-specific immune pressures also select for mutations flanking CD8 epitopes that impair antigen processing. In persons expressing HLA-A3, we demonstrate consistent selection for a mutation in a C-terminal flanking residue of the normally immunodominant Gag KK9 epitope that prevents its processing and presentation, resulting in a rapid decline in the CD8 T-cell response. This single amino acid substitution also lies within a second HLA-A3-restricted epitope, with the mutation directly impairing recognition by CD8 T cells. Transmission of the mutation to subjects expressing HLA-A3 was shown to prevent the induction of normally immunodominant acute-phase responses to both epitopes. However, subsequent in vivo reversion of the mutation was coincident with delayed induction of new CD8 T-cell responses to both epitopes. These data demonstrate that mutations within the flanking region of an HIV-1 epitope can impair recognition by an established CD8 T-cell response and that transmission of these mutations alters the acute-phase CD8+ T-cell response. Moreover, reversion of these mutations in the absence of the original immune pressure reveals the potential plasticity of immunologically selected evolutionary changes. PMID:15194783

  13. Mitochondrial Superoxide Signaling Contributes to Norepinephrine-Mediated T-Lymphocyte Cytokine Profiles

    PubMed Central

    Roessner, Colton T.; Tian, Jun; Zimmerman, Matthew C.

    2016-01-01

    Norepinephrine (NE) produces multifaceted regulatory patterns in T-lymphocytes. Recently, we have shown that NE utilizes redox signaling as evidenced by increased superoxide (O2●-) causally linked to the observed changes in these cells; however, the source of this reactive oxygen species (ROS) remains elusive. Herein, we hypothesized that the source of increased O2●- in NE-stimulated T-lymphocytes is due to disruption of mitochondrial bioenergetics. To address this hypothesis, we utilized purified mouse splenic CD4+ and CD8+ T-lymphocytes stimulated with NE and assessed O2●- levels, mitochondrial metabolism, cellular proliferation, and cytokine profiles. We demonstrate that the increase in O2●- levels in response to NE is time-dependent and occurs at later points of T-lymphocyte activation. Moreover, the source of O2●- was indeed the mitochondria as evidenced by enhanced MitoSOX Red oxidation as well as abrogation of this signal by the addition of the mitochondrial-targeted O2●--scavenging antioxidant MitoTempol. NE-stimulated T-lymphocytes also demonstrated decreased mitochondrial respiratory capacity, which suggests disruption of mitochondrial metabolism and the potential source of increased mitochondrial O2●-. The effects of NE in regards to redox signaling appear to be adrenergic receptor-dependent as specific receptor antagonists could reverse the increase in O2●-; however, differential receptors regulating these processes were observed in CD4+ versus CD8+ T-lymphocytes. Finally, mitochondrial O2●- was shown to be mechanistic to the NE-mediated T-lymphocyte phenotype as supplementation of MitoTempol could reverse specific changes in cytokine expression observed with NE treatment. Overall, these studies indicate that mitochondrial metabolism and O2●--mediated redox signaling play a regulatory role in the T-lymphocyte response to NE. PMID:27727316

  14. An Efficient Low Cost Method for Gene Transfer to T Lymphocytes

    PubMed Central

    Chicaybam, Leonardo; Sodre, Andressa Laino; Curzio, Bianca Azevedo; Bonamino, Martin Hernan

    2013-01-01

    Gene transfer to T lymphocytes has historically relied on retro and lentivirus, but recently transposon-based gene transfer is rising as a simpler and straight forward approach to achieve stable transgene expression. Transfer of expression cassettes to T lymphocytes remains challenging, being based mainly on commercial kits. Aims We herein report a convenient and affordable method based on in house made buffers, generic cuvettes and utilization of the widely available Lonza nucleofector II device to promote efficient gene transfer to T lymphocytes. Results This approach renders high transgene expression levels in primary human T lymphocytes (mean 45%, 41–59%), the hard to transfect murine T cells (mean 38%, 36–42% for C57/BL6 strain) and human Jurkat T cell line. Cell viability levels after electroporation allowed further manipulations such as in vitro expansion and Chimeric Antigen Receptor (CAR) mediated gain of function for target cell lysis. Conclusions We describe here an efficient general protocol for electroporation based modification of T lymphocytes. By opening access to this protocol, we expect that efficient gene transfer to T lymphocytes, for transient or stable expression, may be achieved by an increased number of laboratories at lower and affordable costs. PMID:23555950

  15. The influence of aminophylline on the nanostructure and nanomechanics of T lymphocytes: an AFM study

    NASA Astrophysics Data System (ADS)

    Huang, Xun; He, Jiexiang; Liu, Mingxian; Zhou, Changren

    2014-09-01

    Although much progress has been made in the illustration of the mechanism of aminophylline (AM) treating asthma, there is no data about its effect on the nanostructure and nanomechanics of T lymphocytes. Here, we presented atomic force spectroscopy (AFM)-based investigations at the nanoscale level to address the above fundamental biophysical questions. As increasing AM treatment time, T lymphocytes' volume nearly double increased and then decreased. The changes of nanostructural features of the cell membrane, i.e., mean height of particles, root-mean-square roughness (Rq), crack and fragment appearance, increased with AM treatment time. T lymphocytes were completely destroyed with 96-h treatment, and they existed in the form of small fragments. Analysis of force-distance curves showed that the adhesion force of cell surface decreased significantly with the increase of AM treatment time, while the cell stiffness increased firstly and then decreased. These changes were closely correlated to the characteristics and process of cell oncosis. In total, these quantitative and qualitative changes of T lymphocytes' structure and nanomechanical properties suggested that AM could induce T lymphocyte oncosis to exert anti-inflammatory effects for treating asthma. These findings provide new insights into the T lymphocyte oncosis and the anti-inflammatory mechanism and immune regulation actions of AM.

  16. In Vivo Magnetic Resonance Imaging of CD8+ T Lymphocytes Recruiting to Glioblastoma in Mice.

    PubMed

    Li, Anning; Wu, Yue; Tang, Feng; Li, Wei; Feng, Xiaoyuan; Yao, Zhenwei

    2016-11-01

    Noninvasive in vivo tracking of adopted immune cells would help improve immunotherapy on glioblastoma. In this study, the authors tried to track adoptive CD8+ T lymphocytes in an in situ GL261 glioblastoma mouse model with magnetic resonance imaging (MRI). CD8+ T lymphocytes from spleen of preimmunized GL261 glioblastoma mice were labeled with superparamagnetic iron oxide, with polylysine as transfection agent. From Prussian blue staining, the labeling efficiency was 0.77% ± 0.06%, without altering cell viability and function. From anti-CD8, and anti-dextran staining, superparamagnetic iron oxide could be seen in the cytoplasm. In vitro imaging of agar gel mixtures with different concentrations of labeled CD8+ T lymphocytes was done with a 3.0T MR T2*WI sequence. Higher cell concentrations showed lower signal values. Twenty-four hours after tail vein injection of labeled and unlabeled CD8+ T lymphocytes, imaging of GL261 mice brain showed black spots at the periphery of the tumor in the labeled group only. Brain tumor pathology further verified infiltration of labeled CD8+ T lymphocytes in the tumor. Thus, preimmunized CD8+ T lymphocytes could be efficiently labeled with superparamagnetic iron oxide and tracked both in vitro and in vivo with 3.0T MRI.

  17. Protection against lethal cytomegalovirus infection by a recombinant vaccine containing a single nonameric T-cell epitope.

    PubMed Central

    Del Val, M; Schlicht, H J; Volkmer, H; Messerle, M; Reddehase, M J; Koszinowski, U H

    1991-01-01

    The regulatory immediate-early (IE) protein pp89 of murine cytomegalovirus induces CD8+ T lymphocytes that protect against lethal murine cytomegalovirus infection. The IE1 epitope is the only epitope of pp89 that is recognized by BALB/c cytolytic T lymphocytes (CTL). Using synthetic peptides, the optimal and minimal antigenic sequences of the IE1 epitope have been defined. To evaluate the predictive value of data obtained with synthetic peptides, recombinant vaccines encoding this single T-cell epitope were constructed using as a vector the hepatitis B virus core antigen encoded in recombinant vaccinia virus. In infected cells expressing the chimeric proteins, only IE1 epitope sequences that were recognized as synthetic peptides at concentrations lower than 10(-6) M were presented to CTL. Vaccination of mice with the recombinant vaccinia virus that encoded a chimeric protein carrying the optimal 9-amino-acid IE1 epitope sequence elicited CD8+ T lymphocytes with antiviral activity and, furthermore, protected against lethal disease. The results thus show for the first time that recombinant vaccines containing a single foreign nonameric CTL epitope can induce T-lymphocyte-mediated protective immunity. Images PMID:1710286

  18. Nonmuscle myosin heavy chain IIA mediates integrin LFA-1 de-adhesion during T lymphocyte migration.

    PubMed

    Morin, Nicole A; Oakes, Patrick W; Hyun, Young-Min; Lee, Dooyoung; Chin, Y Eugene; Chin, Eugene Y; King, Michael R; Springer, Timothy A; Shimaoka, Motomu; Tang, Jay X; Reichner, Jonathan S; Kim, Minsoo

    2008-01-21

    Precise spatial and temporal regulation of cell adhesion and de-adhesion is critical for dynamic lymphocyte migration. Although a great deal of information has been learned about integrin lymphocyte function-associated antigen (LFA)-1 adhesion, the mechanism that regulates efficient LFA-1 de-adhesion from intercellular adhesion molecule (ICAM)-1 during T lymphocyte migration is unknown. Here, we show that nonmuscle myosin heavy chain IIA (MyH9) is recruited to LFA-1 at the uropod of migrating T lymphocytes, and inhibition of the association of MyH9 with LFA-1 results in extreme uropod elongation, defective tail detachment, and decreased lymphocyte migration on ICAM-1, without affecting LFA-1 activation by chemokine CXCL-12. This defect was reversed by a small molecule antagonist that inhibits both LFA-1 affinity and avidity regulation, but not by an antagonist that inhibits only affinity regulation. Total internal reflection fluorescence microscopy of the contact zone between migrating T lymphocytes and ICAM-1 substrate revealed that inactive LFA-1 is selectively localized to the posterior of polarized T lymphocytes, whereas active LFA-1 is localized to their anterior. Thus, during T lymphocyte migration, uropodal adhesion depends on LFA-1 avidity, where MyH9 serves as a key mechanical link between LFA-1 and the cytoskeleton that is critical for LFA-1 de-adhesion.

  19. Mutant Huntingtin Does Not Affect the Intrinsic Phenotype of Human Huntington's Disease T Lymphocytes.

    PubMed

    Miller, James R C; Träger, Ulrike; Andre, Ralph; Tabrizi, Sarah J

    2015-01-01

    Huntington's disease is a fatal neurodegenerative condition caused by a CAG repeat expansion in the huntingtin gene. The peripheral innate immune system is dysregulated in Huntington's disease and may contribute to its pathogenesis. However, it is not clear whether or to what extent the adaptive immune system is also involved. Here, we carry out the first comprehensive investigation of human ex vivo T lymphocytes in Huntington's disease, focusing on the frequency of a range of T lymphocyte subsets, as well as analysis of proliferation, cytokine production and gene transcription. In contrast to the innate immune system, the intrinsic phenotype of T lymphocytes does not appear to be affected by the presence of mutant huntingtin, with Huntington's disease T lymphocytes exhibiting no significant functional differences compared to control cells. The transcriptional profile of T lymphocytes also does not appear to be significantly affected, suggesting that peripheral immune dysfunction in Huntington's disease is likely to be mediated primarily by the innate rather than the adaptive immune system. This study increases our understanding of the effects of Huntington's disease on peripheral tissues, while further demonstrating the differential effects of the mutant protein on different but related cell types. Finally, this study suggests that the potential use of novel therapeutics aimed at modulating the Huntington's disease innate immune system should not be extended to include the adaptive immune system.

  20. NAFLD causes selective CD4+ T lymphocyte loss and promotes hepatocarcinogenesis

    PubMed Central

    Ma, Chi; Kesarwala, Aparna H.; Eggert, Tobias; Medina-Echeverz, José; Kleiner, David E.; Jin, Ping; Stroncek, David F.; Terabe, Masaki; Kapoor, Veena; ElGindi, Mei; Han, Miaojun; Thornton, Angela M.; Zhang, Haibo; Egger, Michèle; Luo, Ji; Felsher, Dean W.; McVicar, Daniel W.; Weber, Achim; Heikenwalder, Mathias; Greten, Tim F.

    2016-01-01

    Summary Hepatocellular carcinoma (HCC) is the second most common cause of cancer related death. Non-alcoholic fatty liver disease (NAFLD) affects a large proportion of the US population and is considered a metabolic predisposition to liver cancer 1-5. However, the role of adaptive immune responses in NAFLD-promoted HCC is largely unknown. Here, we show that dysregulation of lipid metabolism in NAFLD causes a selective loss of intrahepatic CD4+ but not CD8+ T lymphocytes leading to accelerated hepatocarcinogenesis. We also found that CD4+ T lymphocytes have greater mitochondrial mass than CD8+ T lymphocytes and generate higher levels of mitochondrially-derived reactive oxygen species (ROS). Disruption of mitochondrial function by linoleic acid, a fatty acid accumulated in NAFLD, causes more oxidative damage than other free fatty acids such as palmitic acid, and mediates selective loss of intrahepatic CD4+ T lymphocytes. In vivo blockade of ROS reversed NAFLD-induced hepatic CD4+ T lymphocyte decrease and delayed NAFLD-promoted HCC. Our results provide an unexpected link between lipid dysregulation and impaired anti-tumor surveillance. PMID:26934227

  1. Genetic modification of human T lymphocytes for the treatment of hematologic malignancies

    PubMed Central

    Hoyos, Valentina; Savoldo, Barbara; Dotti, Gianpietro

    2012-01-01

    Modern chemotherapy regimens and supportive care have produced remarkable improvements in the overall survival of patients with hematologic malignancies. However, the development of targeted small molecules, monoclonal antibodies, and biological therapies that demonstrate greater efficacy and lower toxicity remains highly desirable in hematology, and oncology in general. In the context of biological therapies, T-lymphocyte based treatments have enormous potential. Donor lymphocyte infusion in patients relapsed after allogeneic hematopoietic stem cell transplant pioneered the concept that T lymphocytes can effectively control tumor growth, and this was then followed by the development of cell culture strategies to generate T lymphocytes with selective activity against tumor cells. Over the past decade, it has become clear that the adoptive transfer of ex vivo expanded antigen-specific cytotoxic T lymphocytes promotes sustained antitumor effects in patients with virus-associated lymphomas, such as Epstein-Barr virus related post-transplant lymphomas and Hodgkin's lymphomas. Because of this compelling clinical evidence and the concomitant development of methodologies for robust gene transfer to human T lymphocytes, the field has rapidly evolved, offering new opportunities to extend T-cell based therapies. This review summarizes the most recent biological and clinical developments using genetically manipulated T cells for the treatment of hematologic malignancies. PMID:22929977

  2. Phosphoinositide lipid phosphatases: natural regulators of phosphoinositide 3-kinase signaling in T lymphocytes.

    PubMed

    Harris, Stephanie J; Parry, Richard V; Westwick, John; Ward, Stephen G

    2008-02-01

    The phosphoinositide 3-kinase signaling pathway has been implicated in a range of T lymphocyte cellular functions, particularly growth, proliferation, cytokine secretion, and survival. Dysregulation of phosphoinositide 3-kinase-dependent signaling and function in leukocytes, including B and T lymphocytes, has been implicated in many inflammatory and autoimmune diseases. As befits a pivotal signaling cascade, several mechanisms exist to ensure that the pathway is tightly regulated. This minireview focuses on two lipid phosphatases, viz. the 3'-phosphatase PTEN (phosphatase and tensin homolog deleted on chromosome 10) and SHIP (Src homology 2 domain-containing inositol-5-phosphatase). We discuss their role in regulating T lymphocyte signaling as well their potential as future therapeutic targets.

  3. T lymphocyte-derived demyelinating activity in multiple sclerosis patients in relapse.

    PubMed Central

    Selmaj, K; Alam, R; Perkin, G D; Rose, F C

    1987-01-01

    Supernatants of cultured T lymphocytes of multiple sclerosis patients were tested for a demyelinating activity in rat cerebellum explant cultures. Supernatants of unstimulated T lymphocytes in seven out of 10 multiple sclerosis patients in relapse produced demyelination when checked by phase contrast microscopy. Supernatants of unstimulated T lymphocytes from healthy subjects did not produce demyelination, but when T cells were stimulated by phytohaemagglutinin (PHA), 50% of tested supernatants produced demyelination, which was, however, never as advanced as in multiple sclerosis supernatant treated cerebellum cultures. The demyelinating activity proved to be heat labile. Gel filtration study revealed two fractions of the demyelinating activity 12.5-29.0 kD and 43.0-66.0 kD. The results suggest that lymphokines can be directly involved in the pathogenesis of demyelination in multiple sclerosis. Images PMID:3495638

  4. Serotype b of Aggregatibacter actinomycetemcomitans increases osteoclast and memory T-lymphocyte activation.

    PubMed

    Melgar-Rodríguez, S; Díaz-Zúñiga, J; Alvarez, C; Rojas, L; Monasterio, G; Carvajal, P; Escobar, A; Sanz, M; Vernal, R

    2016-04-01

    During periodontitis, alveolar bone resorption is associated with activation of T helper type 17 (Th17) lymphocytes and receptor activator of nuclear factor-κB ligand (RANKL) -induced osteoclasts. We previously reported that serotype b of Aggregatibacter actinomycetemcomitans has a higher capacity to trigger Th17-type differentiation and function in activated T lymphocytes and its lipopolysaccharide is a more potent immunogen compared with the other serotypes. This study aimed to investigate whether serotype b of A. actinomycetemcomitans induces higher Th17-associated RANKL production, RANKL-induced osteoclast activation, and antigen-specific memory T lymphocyte proliferation. On naive CD4(+) T lymphocytes stimulated with autologous dendritic cells primed with different A. actinomycetemcomitans serotypes, RANKL production, T-bet, GATA-3, RORC2 and Foxp3 expression, RORC2/RANKL intracellular double-expression, TRAP(+) osteoclast activation, and bone resorption were quantified. The frequency of proliferating memory T lymphocytes in response to A. actinomycetemcomitans serotypes was determined in periodontitis and healthy subjects. Naive CD4(+) T lymphocytes stimulated by serotype b-primed dendritic cells elicited higher levels of RANKL, RORC2, TRAP(+) osteoclasts, and bone resorption than the same cells stimulated with the other serotypes. RANKL positively correlated and co-expressed with RORC2. Memory T lymphocytes responding to serotype b were more frequently detected in periodontitis patients than healthy subjects. These results indicate that serotype b of A. actinomycetemcomitans is associated with higher production of RANKL and these increased levels are associated with Th17 lymphocyte induction, osteoclast activation, and bone resorption.

  5. Inhibition of anti-tuberculosis T-lymphocyte function with tumour necrosis factor antagonists.

    PubMed

    Hamdi, Haïfa; Mariette, Xavier; Godot, Véronique; Weldingh, Karin; Hamid, Abdul Monem; Prejean, Maria-Victoria; Baron, Gabriel; Lemann, Marc; Puechal, Xavier; Breban, Maxime; Berenbaum, Francis; Delchier, Jean-Charles; Flipo, René-Marc; Dautzenberg, Bertrand; Salmon, Dominique; Humbert, Marc; Emilie, Dominique

    2006-01-01

    Reactivation of latent Mycobacterium tuberculosis (Mtb) infection is a major complication of anti-tumour necrosis factor (TNF)-alpha treatment, but its mechanism is not fully understood. We evaluated the effect of the TNF antagonists infliximab (Ifx), adalimumab (Ada) and etanercept (Eta) on anti-mycobacterial immune responses in two conditions: with ex vivo studies from patients treated with TNF antagonists and with the in vitro addition of TNF antagonists to cells stimulated with mycobacterial antigens. In both cases, we analysed the response of CD4+ T lymphocytes to purified protein derivative (PPD) and to culture filtrate protein (CFP)-10, an antigen restricted to Mtb. The tests performed were lymphoproliferation and immediate production of interferon (IFN)-gamma. In the 68 patients with inflammatory diseases (rheumatoid arthritis, spondylarthropathy or Crohn's disease), including 31 patients with a previous or latent tuberculosis (TB), 14 weeks of anti-TNF-alpha treatment had no effect on the proliferation of CD4+ T lymphocytes. In contrast, the number of IFN-gamma-releasing CD4+ T lymphocytes decreased for PPD (p < 0.005) and CFP-10 (p < 0.01) in patients with previous TB and for PPD (p < 0.05) in other patients (all vaccinated with Bacille Calmette-Guérin). Treatments with Ifx and with Eta affected IFN-gamma release to a similar extent. In vitro addition of TNF antagonists to CD4+ T lymphocytes stimulated with mycobacterial antigens inhibited their proliferation and their expression of membrane-bound TNF (mTNF). These effects occurred late in cultures, suggesting a direct effect of TNF antagonists on activated mTNF+ CD4+ T lymphocytes, and Ifx and Ada were more efficient than Eta. Therefore, TNF antagonists have a dual action on anti-mycobacterial CD4+ T lymphocytes. Administered in vivo, they decrease the frequency of the subpopulation of memory CD4+ T lymphocytes rapidly releasing IFN-gamma upon challenge with mycobacterial antigens. Added in vitro, they

  6. Preferential uptake of antioxidant carbon nanoparticles by T lymphocytes for immunomodulation

    PubMed Central

    Huq, Redwan; Samuel, Errol L. G.; Sikkema, William K. A.; Nilewski, Lizanne G.; Lee, Thomas; Tanner, Mark R.; Khan, Fatima S.; Porter, Paul C.; Tajhya, Rajeev B.; Patel, Rutvik S.; Inoue, Taeko; Pautler, Robia G.; Corry, David B.; Tour, James M.; Beeton, Christine

    2016-01-01

    Autoimmune diseases mediated by a type of white blood cell—T lymphocytes—are currently treated using mainly broad-spectrum immunosuppressants that can lead to adverse side effects. Antioxidants represent an alternative approach for therapy of autoimmune disorders; however, dietary antioxidants are insufficient to play this role. Antioxidant carbon nanoparticles scavenge reactive oxygen species (ROS) with higher efficacy than dietary and endogenous antioxidants. Furthermore, the affinity of carbon nanoparticles for specific cell types represents an emerging tactic for cell-targeted therapy. Here, we report that nontoxic poly(ethylene glycol)-functionalized hydrophilic carbon clusters (PEG-HCCs), known scavengers of the ROS superoxide (O2•−) and hydroxyl radical, are preferentially internalized by T lymphocytes over other splenic immune cells. We use this selectivity to inhibit T cell activation without affecting major functions of macrophages, antigen-presenting cells that are crucial for T cell activation. We also demonstrate the in vivo effectiveness of PEG-HCCs in reducing T lymphocyte-mediated inflammation in delayed-type hypersensitivity and in experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. Our results suggest the preferential targeting of PEG-HCCs to T lymphocytes as a novel approach for T lymphocyte immunomodulation in autoimmune diseases without affecting other immune cells. PMID:27654170

  7. The development of in vitro mutagenicity testing systems using T-lymphocytes

    SciTech Connect

    Albertini, R.J.

    1993-05-01

    This annual report describes progress in studies on hprt mutations induced by radon or Indium 111 along with the corresponding mutation frequency, cloning and molecular spectra in human T-lymphocytes. Parallel studies on the mutation susceptibility between individuals is being investigated by hprt mutation studies on ataxia telangiectasia and xeroderma pigmentosum.

  8. Catastrophic NAD+ Depletion in Activated T Lymphocytes through Nampt Inhibition Reduces Demyelination and Disability in EAE

    PubMed Central

    Ferrando, Tiziana; Poggi, Alessandro; Garuti, Anna; D'Urso, Agustina; Selmo, Martina; Benvenuto, Federica; Cea, Michele; Zoppoli, Gabriele; Moran, Eva; Soncini, Debora; Ballestrero, Alberto; Sordat, Bernard; Patrone, Franco; Mostoslavsky, Raul; Uccelli, Antonio; Nencioni, Alessio

    2009-01-01

    Nicotinamide phosphoribosyltransferase (Nampt) inhibitors such as FK866 are potent inhibitors of NAD+ synthesis that show promise for the treatment of different forms of cancer. Based on Nampt upregulation in activated T lymphocytes and on preliminary reports of lymphopenia in FK866 treated patients, we have investigated FK866 for its capacity to interfere with T lymphocyte function and survival. Intracellular pyridine nucleotides, ATP, mitochondrial function, viability, proliferation, activation markers and cytokine secretion were assessed in resting and in activated human T lymphocytes. In addition, we used experimental autoimmune encephalomyelitis (EAE) as a model of T-cell mediated autoimmune disease to assess FK866 efficacy in vivo. We show that activated, but not resting, T lymphocytes undergo massive NAD+ depletion upon FK866-mediated Nampt inhibition. As a consequence, impaired proliferation, reduced IFN-γ and TNF-α production, and finally autophagic cell demise result. We demonstrate that upregulation of the NAD+-degrading enzyme poly-(ADP-ribose)-polymerase (PARP) by activated T cells enhances their susceptibility to NAD+ depletion. In addition, we relate defective IFN-γ and TNF-α production in response to FK866 to impaired Sirt6 activity. Finally, we show that FK866 strikingly reduces the neurological damage and the clinical manifestations of EAE. In conclusion, Nampt inhibitors (and possibly Sirt6 inhibitors) could be used to modulate T cell-mediated immune responses and thereby be beneficial in immune-mediated disorders. PMID:19936064

  9. Heparanase promotes tumor infiltration and antitumor activity of CAR-redirected T-lymphocytes

    PubMed Central

    Caruana, Ignazio; Savoldo, Barbara; Hoyos, Valentina; Weber, Gerrit; Liu, Hao; Kim, Eugene S.; Ittmann, Michael M.; Marchetti, Dario; Dotti, Gianpietro

    2015-01-01

    Adoptive transfer of chimeric antigen receptor (CAR)-redirected T lymphocytes (CAR-T cells) has had less striking effects in solid tumors1–3 than in lymphoid malignancies4, 5. Although active tumor-mediated immunosuppression may play a role in limiting efficacy6, functional changes in T lymphocytes following their ex vivo manipulation may also account for cultured CAR-T cells’ reduced ability to penetrate stroma-rich solid tumors. We therefore studied the capacity of human in vitro-cultured CAR-T cells to degrade components of the extracellular matrix (ECM). In contrast to freshly isolated T lymphocytes, we found that in vitro-cultured T lymphocytes lack expression of the enzyme heparanase (HPSE) that degrades heparan sulphate proteoglycans, which are main components of ECM. We found that HPSE mRNA is down regulated in in vitro-expanded T cells, which may be a consequence of p53 binding to the HPSE gene promoter. We therefore engineered CAR-T cells to express HPSE and showed improved capacity to degrade ECM, which promoted tumor T-cell infiltration and antitumor activity. Employing this strategy may enhance the activity of CAR-T cells in individuals with stroma-rich solid tumors. PMID:25849134

  10. T Lymphocyte Maturation Is Impaired in Healthy Young Individuals Carrying Trisomy 21 (Down Syndrome)

    ERIC Educational Resources Information Center

    Guazzarotti, Laura; Trabattoni, Daria; Castelletti, Eleonora; Boldrighini, Benedetta; Piacentini, Luca; Duca, Piergiorgio; Beretta, Silvia; Pacei, Michela; Caprio, Cristiana; Vigano, Alessandra; di Natale, Berardo; Zuccotti, Gian Vincenzo; Clerici, Mario

    2009-01-01

    Cytokine production, immune activation, T lymphocytes maturation, and serum IL-7 concentration were examined in 24 youngsters with Down syndrome and no acquired diseases (healthy Down syndrome [12 prepubertal, 13 pubertal]) and 42 age- and gender-matched controls (20 prepubertal, 22 pubertal). Results showed that a complex immune and impairment is…

  11. Myxoma virus suppresses proliferation of activated T lymphocytes yet permits oncolytic virus transfer to cancer cells

    PubMed Central

    Villa, Nancy Y.; Wasserfall, Clive H.; Meacham, Amy M.; Wise, Elizabeth; Chan, Winnie; Wingard, John R.; McFadden, Grant

    2015-01-01

    Allogeneic hematopoietic cell transplant (allo-HCT) can be curative for certain hematologic malignancies, but the risk of graft-versus-host disease (GVHD) is a major limitation for wider application. Ideally, strategies to improve allo-HCT would involve suppression of T lymphocytes that drive GVHD while sparing those that mediate graft-versus-malignancy (GVM). Recently, using a xenograft model, we serendipitously discovered that myxoma virus (MYXV) prevented GVHD while permitting GVM. In this study, we show that MYXV binds to resting, primary human T lymphocytes but will only proceed into active virus infection after the T cells receive activation signals. MYXV-infected T lymphocytes exhibited impaired proliferation after activation with reduced expression of interferon-γ, interleukin-2 (IL-2), and soluble IL-2Rα, but did not affect expression of IL-4 and IL-10. MYXV suppressed T-cell proliferation in 2 patterns (full vs partial) depending on the donor. In terms of GVM, we show that MYXV-infected activated human T lymphocytes effectively deliver live oncolytic virus to human multiple myeloma cells, thus augmenting GVM by transfer of active oncolytic virus to residual cancer cells. Given this dual capacity of reducing GVHD plus increasing the antineoplastic effectiveness of GVM, ex vivo virotherapy with MYXV may be a promising clinical adjunct to allo-HCT regimens. PMID:25904246

  12. Myxoma virus suppresses proliferation of activated T lymphocytes yet permits oncolytic virus transfer to cancer cells.

    PubMed

    Villa, Nancy Y; Wasserfall, Clive H; Meacham, Amy M; Wise, Elizabeth; Chan, Winnie; Wingard, John R; McFadden, Grant; Cogle, Christopher R

    2015-06-11

    Allogeneic hematopoietic cell transplant (allo-HCT) can be curative for certain hematologic malignancies, but the risk of graft-versus-host disease (GVHD) is a major limitation for wider application. Ideally, strategies to improve allo-HCT would involve suppression of T lymphocytes that drive GVHD while sparing those that mediate graft-versus-malignancy (GVM). Recently, using a xenograft model, we serendipitously discovered that myxoma virus (MYXV) prevented GVHD while permitting GVM. In this study, we show that MYXV binds to resting, primary human T lymphocytes but will only proceed into active virus infection after the T cells receive activation signals. MYXV-infected T lymphocytes exhibited impaired proliferation after activation with reduced expression of interferon-γ, interleukin-2 (IL-2), and soluble IL-2Rα, but did not affect expression of IL-4 and IL-10. MYXV suppressed T-cell proliferation in 2 patterns (full vs partial) depending on the donor. In terms of GVM, we show that MYXV-infected activated human T lymphocytes effectively deliver live oncolytic virus to human multiple myeloma cells, thus augmenting GVM by transfer of active oncolytic virus to residual cancer cells. Given this dual capacity of reducing GVHD plus increasing the antineoplastic effectiveness of GVM, ex vivo virotherapy with MYXV may be a promising clinical adjunct to allo-HCT regimens.

  13. Activation effects of polysaccharides of Flammulina velutipes mycorrhizae on the T lymphocyte immune function.

    PubMed

    Yan, Zheng-Fei; Liu, Nai-Xu; Mao, Xin-Xin; Li, Yu; Li, Chang-Tian

    2014-01-01

    Flammulina velutipes mycorrhizae have increasingly been produced with increasing of F. velutipes production. A mouse model was thus used to examine potential effect of F. velutipes mycorrhizae on the immune function. Fifty female Wistar mice (5-weeks-old) weighed 15-20 g were randomly allocated into five groups. Polysaccharide of F. velutipes mycorrhizae were treated with mice and mice spleen lymphocytes. The levels of CD3(+), CD4(+), and CD8(+) T lymphocyte, interleukin-2 (IL-2), and tumor necrosis factor-a (TNF-α) were determined. The results showed that the proportions of CD3(+), and CD4(+) T lymphocyte, the ratio of CD4(+)/CD8(+), and the levels of IL-2 and TNF-a were significantly increased in polysaccharide of F. velutipes mycorrhizae, while the proportion of CD8(+) T lymphocyte was decreased in polysaccharide of F. velutipes mycorrhizae-dose dependent manner. Our findings indicated that a long term exposure of polysaccharide of F. velutipes mycorrhizae could activate the T lymphocyte immune function. Polysaccharide of F. velutipes mycorrhizae was expected to develop into the immune health products.

  14. ALS patients' regulatory T lymphocytes are dysfunctional, and correlate with disease progression rate and severity.

    PubMed

    Beers, David R; Zhao, Weihua; Wang, Jinghong; Zhang, Xiujun; Wen, Shixiang; Neal, Dan; Thonhoff, Jason R; Alsuliman, Abdullah S; Shpall, Elizabeth J; Rezvani, Katy; Appel, Stanley H

    2017-03-09

    Neuroinflammation is a pathological hallmark of ALS in both transgenic rodent models and patients, and is characterized by proinflammatory T lymphocytes and activated macrophages/microglia. In ALS mouse models, decreased regulatory T lymphocytes (Tregs) exacerbate the neuroinflammatory process, leading to accelerated motoneuron death and shortened survival; passive transfer of Tregs suppresses the neuroinflammation and prolongs survival. Treg numbers and FOXP3 expression are also decreased in rapidly progressing ALS patients. A key question is whether the marked neuroinflammation in ALS can be attributed to the impaired suppressive function of ALS Tregs in addition to their decreased numbers. To address this question, T lymphocyte proliferation assays were performed. Compared with control Tregs, ALS Tregs were less effective in suppressing responder T lymphocyte proliferation. Although both slowly and rapidly progressing ALS patients had dysfunctional Tregs, the greater the clinically assessed disease burden or the more rapidly progressing the patient, the greater the Treg dysfunction. Epigenetically, the percentage methylation of the Treg-specific demethylated region was greater in ALS Tregs. After in vitro expansion, ALS Tregs regained suppressive abilities to the levels of control Tregs, suggesting that autologous passive transfer of expanded Tregs might offer a novel cellular therapy to slow disease progression.

  15. ALS patients’ regulatory T lymphocytes are dysfunctional, and correlate with disease progression rate and severity

    PubMed Central

    Beers, David R.; Zhao, Weihua; Wang, Jinghong; Zhang, Xiujun; Wen, Shixiang; Neal, Dan; Thonhoff, Jason R.; Alsuliman, Abdullah S.; Shpall, Elizabeth J.; Rezvani, Katy

    2017-01-01

    Neuroinflammation is a pathological hallmark of ALS in both transgenic rodent models and patients, and is characterized by proinflammatory T lymphocytes and activated macrophages/microglia. In ALS mouse models, decreased regulatory T lymphocytes (Tregs) exacerbate the neuroinflammatory process, leading to accelerated motoneuron death and shortened survival; passive transfer of Tregs suppresses the neuroinflammation and prolongs survival. Treg numbers and FOXP3 expression are also decreased in rapidly progressing ALS patients. A key question is whether the marked neuroinflammation in ALS can be attributed to the impaired suppressive function of ALS Tregs in addition to their decreased numbers. To address this question, T lymphocyte proliferation assays were performed. Compared with control Tregs, ALS Tregs were less effective in suppressing responder T lymphocyte proliferation. Although both slowly and rapidly progressing ALS patients had dysfunctional Tregs, the greater the clinically assessed disease burden or the more rapidly progressing the patient, the greater the Treg dysfunction. Epigenetically, the percentage methylation of the Treg-specific demethylated region was greater in ALS Tregs. After in vitro expansion, ALS Tregs regained suppressive abilities to the levels of control Tregs, suggesting that autologous passive transfer of expanded Tregs might offer a novel cellular therapy to slow disease progression. PMID:28289705

  16. Study of membrane potential in T lymphocytes subpopulations using flow cytometry

    PubMed Central

    Mello de Queiroz, Fernanda; Ponte, Cristiano G; Bonomo, Adriana; Vianna-Jorge, Rosane; Suarez-Kurtz, Guilherme

    2008-01-01

    Background Ion channels are involved in the control of membrane potential (ψ) in a variety of cells. The maintenance of ψ in human T lymphocytes is essential for T-cell activation and was suggested to depend mostly on the voltage-gated Kv1.3 channel. Blockage of Kv1.3 inhibits cytokine production and lymphocyte proliferation in vitro and suppresses immune response in vivo. T lymphocytes are a heterogeneous cell population and the expression of Kv1.3 varies among cell subsets. Oxonol diBA-C4-(3) was used to determine ψ by flow cytometry. The presence of distinct T cell subsets was evaluated by immunophenotyping techniques and the contribution of Kv1.3 channels for the maintenance of ψ was investigated using selective blockers. Results The distribution of ψ in T lymphocytes varied among blood donors and did not always follow a unimodal pattern. T lymphocytes were divided into CD3+/CD45RO- and CD3+/CD45RO+ subsets, whose peak channel values of ψ were -58 ± 3.6 mV and -37 ± 4.1 mV, respectively. MgTX (specific inhibitor of Kv1.3 channels) had no significant effect in the ψ of CD3+/CD45RO- subsets but depolarized CD3+/CD45RO+ cells to -27 ± 5.1 mV. Conclusion Combination of optical methods for determination of ψ by flow cytometry with immuophenotyping techniques opens new possibilities for the study of ion channels in the biology of heterogeneous cell populations such as T lymphocyte subsets. PMID:18980671

  17. Toxoplasma gondii-Infected Human Myeloid Dendritic Cells Induce T-Lymphocyte Dysfunction and Contact-Dependent Apoptosis

    PubMed Central

    Wei, Shuang; Marches, Florentina; Borvak, Jozef; Zou, Weiping; Channon, Jacqueline; White, Michael; Radke, Jay; Cesbron-Delauw, Marie-France; Curiel, Tyler J.

    2002-01-01

    Dendritic cells ignite adaptive immunity by priming naïve T lymphocytes. Human monocyte-derived dendritic cells (MDDCs) infected with Toxoplasma gondii induce T-lymphocyte gamma interferon production and may thus activate T. gondii-specific immunity. However, we now demonstrate that T. gondii-infected MDDCs are poor at activating T lymphocytes and are unable to induce specific cytotoxic T lymphocytes. On the other hand, MDDCs acquiring nonviable T. gondii antigens directly, or indirectly through captured apoptotic or necrotic cell bodies, induce potent T-lymphocyte activation. T lymphocytes exposed to infected MDDCs are significantly impaired in upregulation of CD69 and CD28, are refractory to activation, and die through contact-dependent apoptosis mediated by an as-yet-unidentified mechanism not requiring Fas, tumor necrosis factor-related apoptosis-inducing ligand, leukocyte function antigen 1, intercellular adhesion molecule 1, tumor necrosis factor alpha, interleukin 10, alpha interferon, gamma interferon, prostaglandins, or reactive nitrogen intermediates. Bystander T lymphocytes that were neither infected nor apoptotic were refractory to activation, suggesting global dysfunction. Immunosuppression and T-lymphocyte unresponsiveness and apoptosis are typical of acute T. gondii infection. Our data suggest that infected dendritic cells contribute to these processes. On the other hand, host cells infected with T. gondii are resistant to multiple inducers of apoptosis. Thus, regulation of host cell and bystander cell apoptosis by viable T. gondii may be significant components of a strategy to evade immunity and enhance intracellular parasite survival. PMID:11895936

  18. The Memory Cytotoxic T-Lymphocyte (CTL) Response to Human Cytomegalovirus Infection Contains Individual Peptide-Specific CTL Clones That Have Undergone Extensive Expansion In Vivo

    PubMed Central

    Weekes, Michael P.; Wills, Mark R.; Mynard, Kim; Carmichael, Andrew J.; Sissons, J. G. Patrick

    1999-01-01

    Human cytomegalovirus (HCMV)-specific CD8+ cytotoxic T lymphocytes (CTL) appear to play an important role in the control of virus replication and in protection against HCMV-related disease. We have previously reported high frequencies of memory CTL precursors (CTLp) specific to the HCMV tegument protein pp65 in the peripheral blood of healthy virus carriers. In some individuals, the CTL response to this protein is focused on only a single epitope, whereas in other virus carriers CTL recognized multiple epitopes which we identified by using synthetic peptides. We have analyzed the clonal composition of the memory CTL response to four of these pp65 epitopes by sequencing the T-cell receptors (TCR) of multiple independently derived epitope-specific CTL clones, which were derived by formal single-cell cloning or from clonal CTL microcultures. In all cases, we have observed a high degree of clonal focusing: the majority of CTL clones specific to a defined pp65 peptide from any one virus carrier use only one or two different TCRs at the level of the nucleotide sequence. Among virus carriers who have the same major histocompatibility complex (MHC) class I allele, we observed that CTL from different donors that recognize the same peptide-MHC complex often used the same Vβ segment, although other TCR gene segments and CDR3 length were not in general conserved. We have also examined the clonal composition of CTL specific to pp65 peptides in asymptomatic human immunodeficiency virus-infected individuals. We have observed a similarly focused peptide-specific CTL response. Thus, the large population of circulating HCMV peptide-specific memory CTLp in virus carriers in fact contains individual CTL clones that have undergone extensive clonal expansion in vivo. PMID:9971792

  19. Molecular pathogenesis of T lymphocyte-induced liver injury in alcoholic hepatitis.

    PubMed

    Batey, Robert G; Wang, Jianhua

    2002-07-01

    The development of alcohol-induced liver injury is, in part, a consequence of the immunological/inflammatory response that alcohol stimulates. The abnormalities of immune function in heavy drinkers have been documented well. Cytokines, especially TNF alpha, produced from macrophages/Kupffer cells, play a role in the induction of liver cell necrosis and apoptosis. TNF alpha can cause liver cell apoptosis through the TNF alpha receptor or Fas/CD95 which is expressed by liver cells. Furthermore, chronic ethanol consumption may damage the liver by inhibiting the hepatotrophic and hepatoprotective actions of TNF alpha and other cytokines. There exists an intrinsic lymphocyte population in the normal liver. Intrahepatic T lymphocytes consist of a heterogeneous population of cells that has many and varied functional characteristics in addition to classical T cell activity. The population of intrahepatic T lymphocytes may arise via a thymus-independent pathway. Our recent work has demonstrated the role of liver-associated T lymphocytes in the pathogenesis of alcohol related liver injury initiated by a variety of stimuli such as endotoxin (lipopolysaccharide, LPS) or concanavalin A (Con A). Our studies have, for the first time, suggested that alcohol consumption alone does not lead to the development of marked liver necrosis (at least in the rat), but rather that a second insult is required for this to occur. Liver-associated T lymphocytes in rats spontaneously secrete interleukin-1 alpha, interleukin-6 and TNF alpha in vitro culture. There is a significant decline in the amounts of interleukin-1 alpha and TNF alpha secreted in ethanol-consuming rats compared with non-ethanol consuming rats. The numbers of T cells, NK cells and Kupffer cells in liver perfusates remains stable over a prolonged period of ethanol consumption. However, following Con A injection, there was an inappropriate increase in the amounts of interleukin-6 and TNF alpha secreted in in vitro culture of

  20. Interaction between human lung fibroblasts and T-lymphocytes prevents activation of CD4+ cells

    PubMed Central

    Vancheri, Carlo; Mastruzzo, Claudio; Trovato-Salinaro, Elisa; Gili, Elisa; Lo Furno, Debora; Pistorio, Maria P; Caruso, Massimo; La Rosa, Cristina; Crimi, Claudia; Failla, Marco; Crimi, Nunzio

    2005-01-01

    Background T lymphocytes are demonstrated to play an important role in several chronic pulmonary inflammatory diseases. In this study we provide evidence that human lung fibroblasts are capable of mutually interacting with T-lymphocytes leading to functionally significant responses by T-cells and fibroblasts. Methods Human lung fibroblast were co-cultured with PMA-ionomycin activated T-CD4 lymphocytes for 36 hours. Surface as well as intracellular proteins expression, relevant to fibroblasts and lymphocytes activation, were evaluated by means of flow cytometry and RT-PCR. Proliferative responses of T lymphocytes to concanavalin A were evaluated by the MTT assay. Results In lung fibroblasts, activated lymphocytes promote an increase of expression of cyclooxygenase-2 and ICAM-1, expressed as mean fluorescence intensity (MFI), from 5.4 ± 0.9 and 0.7 ± 0.15 to 9.1 ± 1.5 and 38.6 ± 7.8, respectively. Fibroblasts, in turn, induce a significant reduction of transcription and protein expression of CD69, LFA-1 and CD28 in activated lymphocytes and CD3 in resting lymphocytes. In activated T lymphocytes, LFA-1, CD28 and CD69 expression was 16.6 ± 0.7, 18.9 ± 1.9 and 6.6 ± 1.3, respectively, and was significantly reduced by fibroblasts to 9.4 ± 0.7, 9.4 ± 1.4 and 3.5 ± 1.0. CD3 expression in resting lymphocytes was 11.9 ± 1.4 and was significantly reduced by fibroblasts to 6.4 ± 1.1. Intracellular cytokines, TNF-alpha and IL-10, were evaluated in T lymphocytes. Co-incubation with fibroblasts reduced the number of TNF-alpha positive lymphocytes from 54,4% ± 6.12 to 30.8 ± 2.8, while IL-10 positive cells were unaffected. Finally, co-culture with fibroblasts significantly reduced Con A proliferative response of T lymphocytes, measured as MTT absorbance, from 0.24 ± 0.02 nm to 0.16 ± 0.02 nm. Interestingly, while the activation of fibroblasts is mediated by a soluble factor, a cognate interaction ICAM-1 mediated was demonstrated to be responsible for the modulation

  1. Expression of T-Lymphocyte Markers in Human Epidermal Growth Factor Receptor 2-Positive Breast Cancer

    PubMed Central

    Lee, Changro; Kim, Joo Heung; Lim, Sung Mook; Park, Hyung Seok; Kim, Seung Il; Park, Byeong-Woo

    2016-01-01

    Purpose The present study aimed to examine the clinical implications of CD4, CD8, and FOXP3 expression on the prognosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer using a web-based database, and to compare the immunohistochemical expression of T-lymphocyte markers using primary and metastatic HER2-positive tumor tissues before and after HER2-targeted therapy. Methods Using the cBioPortal for Cancer Genomics and Kaplan-Meier plotter, the mRNA expression, association between T-lymphocyte markers, and survival in HER2-positive cancers were investigated according to various cutoff levels. Immunohistochemistry analysis was performed using paired primary and metastatic tissues of 29 HER2-positive tumors treated with systemic chemotherapy and HER2-directed therapy. Results HER2 mRNA was mutually exclusive of T-lymphocyte markers, and a significant correlation between T-cell markers was observed in the cBioPortal for Cancer Genomics. According to analysis of the Kaplan-Meier plotter, the impact of T-lymphocyte marker expression on survival was statistically insignificant in clinical HER2-positive tumors, irrespective of the cutoff levels. However, in the intrinsic HER2-positive subtype, the individual analyses of T-cell markers except for FOXP3 and combined analysis showed significantly favorable survival irrespective of cutoff points. Although the small clinical sample size made it difficult to show the statistical relevance of immunohistochemistry findings, good responses to neoadjuvant treatments might be associated with positive expression of combined T-lymphocyte markers, and approximately half of the samples showed discordance of combined markers between baseline and resistant tumors. Conclusion T-lymphocyte markers could be favorable prognostic factors in HER2-positive breast cancers; however, a consensus on patient section criteria, detection methods, and cutoff value could not be reached. The resistance to HER2-directed therapy might

  2. Resistance-associated epitopes of HIV-1C-highly probable candidates for a multi-epitope vaccine.

    PubMed

    Sundaramurthi, Jagadish Chandrabose; Swaminathan, Soumya; Hanna, Luke Elizabeth

    2012-10-01

    Earlier studies have identified a large number of immunogenic epitopes in HIV-1. Efforts are required to prioritize these epitopes in order to identify the best candidates for formulating an effective multi-epitope vaccine for HIV. We modeled 155 known cytotoxic T lymphocyte epitopes of HIV-1 subtype C on the 3D structure of HLA-A*0201, HLA-B*2705, and HLA-B*5101 using MODPROPEP, as these alleles are known to be associated with resistance to HIV/slow progression to AIDS. Thirty-six epitopes were identified to bind to all the three HLA alleles with better binding affinity than the control peptides complexed with each HLA allele but not to any of the HLA alleles reported to be associated with susceptibility to HIV infection/rapid progression to disease. As increase in stability of the epitope-HLA complex results in increased immunogenicity, the short-listed epitopes could be suitable candidates for vaccine development. Twenty of the 36 epitopes were polyfunctional in nature adding to their immunological relevance for vaccine design. Further, 9 of the 20 polyfunctional epitopes were found to bind to all three resistance-associated HLA alleles using an additional method, adding worth to their potential as candidates for a vaccine formulation for HIV-1C.

  3. Phenotypical and functional evaluation of CD8+/S6F1+ T lymphocytes in haemophiliac individuals with HIV-1 infection.

    PubMed Central

    Cavallin, F; Traldi, A; Zambello, R

    1993-01-01

    In this study we investigated the distribution of the S6F1 antigen, an epitope of the lymphocyte function-associated antigen, on CD8+ T lymphocytes in a series of 15 HIV-1+ and 20 HIV-1- haemophiliac patients. MoAbs recognizing the S6F1 antigen have been claimed to distinguish between killer effectors (brightly S6F1+ stained) and suppressor cells (dimly S6F1+ stained) within the CD8+ lymphoid population. In addition, we tried to find a correlation between the spontaneous in vitro immunoglobulin synthesis from patients' peripheral blood lymphocytes and the pattern of S6F1 expression. Although the total number of double-positive CD8+/S6F1+ cells was similar in both HIV-1+ and HIV-1- haemophiliac patients, a significant increase in the CD8+/S6F1+ population bright versus dim was documented in HIV-1-infected with respect to HIV-1- haemophiliacs (bright/dim ratio 3.97 +/- 0.61 versus 0.75 +/- 0.1, respectively, P < 0.005). This finding was correlated to a significant increase in spontaneous in vitro immunoglobulin production in HIV-1+ subjects compared with control haemophiliacs (P < 0.005). Purified CD8+ lymphocytes from HIV-1+ subjects showed a reduced suppressor activity on mitogen-induced immunoglobulin production. Taken together, these data suggest that HIV-1 infection favours the generation of CD8+/S6F1+ bright cells with putative cytotoxic-associated function, leading to a progressive reduction in the number of CD8+/S6F1+ dim suppressor lymphocytes. This phenomenon may contribute to the polyclonal hypergammaglobulinaemia present in HIV-1+ haemophiliac patients. PMID:8324903

  4. Cell-cycle-dependent regulation of Ca2+-activated K+ channel in Jurkat T-lymphocyte.

    PubMed

    Morimoto, Takashi; Ohya, Susumu; Hayashi, Hidetoshi; Onozaki, Kikuo; Imaizumi, Yuji

    2007-05-01

    Small-conductance Ca2+-activated K+ (SK2) channel plays an important role in the activation of Jurkat T-lymphocytes by maintaining electrical gradients for the sustained Ca2+ influx. Apamin-sensitive K+ current was significantly decreased with cell-cycle progression from G0/G1 into G2/M phases, and protein expression of SK2 channels showed parallel down-regulation, with its highest expression at early G0/G1 phase. In the G0/G1 phase, the apamin-sensitive component of thapsigargin-induced Ca2+ influx was significantly larger than that in the G2/M phase. These observations suggest that SK2-channel activation may largely contribute to the sustained Ca2+ influx in the G0/G1 phase in comparison of that in the G2/M phase in Jurkat T-lymphocytes.

  5. Deficient interleukin 2 dependent proliferation pathway in T lymphocytes from active and inactive ulcerative colitis patients.

    PubMed Central

    Manzano, L; Alvarez-Mon, M; Vargas, J A; Girón, J A; Abreu, L; Fernández-Corugedo, A; Román, L I; Albarran, F; Durántez, A

    1994-01-01

    There is increasing evidence that ulcerative colitis is associated with an abnormality of the immune system. Although the aetiology remains unknown, it has been suggested that the immune system of these patients is implicated in the pathogenesis of their disease. T cell function was investigated in ulcerative colitis patients and defective phytohaemagglutinin induced T cell mitogenesis was found. The DNA synthesis induced by stimulation with phorbol esters plus ionophore (ionomycin), however, was normal. These changes cannot be ascribed to either decreased interleukin 2 synthesis or to a defective interleukin 2 receptor expression after cellular activation. Moreover, this defective proliferative response of the T lymphocytes was observed even in the presence of saturated concentrations of exogenous interleukin 2. These results emphasise that the interleukin 2 dependent proliferation pathway is deficient in T lymphocytes from ulcerative colitis patients. PMID:8063224

  6. γδ T lymphocytes are recruited into the inflamed uterus of bitches suffering from pyometra.

    PubMed

    Bartoskova, A; Turanek-Knotigova, P; Matiasovic, J; Oreskovic, Z; Vicenova, M; Stepanova, H; Ondrackova, P; Vitasek, R; Leva, L; Moore, P F; Faldyna, M

    2012-12-01

    Very little is known about the occurrence of immune system cells in the canine uterus. The aim of this study was to generate information about lymphocyte subsets that are present in the healthy canine uterus and that are recruited under inflammatory conditions caused by pyometra. Using immunohistochemistry and flow cytometry, a significant influx of γδ T lymphocytes was found in pyometra samples mainly due to recruitment of γδ(+)/CD8(-) T lymphocytes. The relative expression of genes encoding selected cytokines/chemokines was evaluated in samples from healthy and pyometra-affected uteri. Expression of pro-inflammatory cytokines (including IL-1β, TNF-α, IL-8, IL-17 and IFN-γ) and chemokines (including CXCL10, CCL4 and CCL5) was upregulated in pyometra samples confirming the presence of inflammation. In contrast, the expression of the homeostatic chemokine CCL25 and of the anti-inflammatory cytokine IL-10 was downregulated and unchanged, respectively.

  7. Generation of tumor-targeted human T lymphocytes from induced pluripotent stem cells for cancer therapy.

    PubMed

    Themeli, Maria; Kloss, Christopher C; Ciriello, Giovanni; Fedorov, Victor D; Perna, Fabiana; Gonen, Mithat; Sadelain, Michel

    2013-10-01

    Progress in adoptive T-cell therapy for cancer and infectious diseases is hampered by the lack of readily available, antigen-specific, human T lymphocytes. Pluripotent stem cells could provide an unlimited source of T lymphocytes, but the therapeutic potential of human pluripotent stem cell-derived lymphoid cells generated to date remains uncertain. Here we combine induced pluripotent stem cell (iPSC) and chimeric antigen receptor (CAR) technologies to generate human T cells targeted to CD19, an antigen expressed by malignant B cells, in tissue culture. These iPSC-derived, CAR-expressing T cells display a phenotype resembling that of innate γδ T cells. Similar to CAR-transduced, peripheral blood γδ T cells, the iPSC-derived T cells potently inhibit tumor growth in a xenograft model. This approach of generating therapeutic human T cells 'in the dish' may be useful for cancer immunotherapy and other medical applications.

  8. Rapid Quantification of Mitogen-induced Blastogenesis in T Lymphocytes for Identifying Immunomodulatory Drugs

    PubMed Central

    Gibson, Jennifer N.; Beesetty, Pavani; Sulentic, Courtney; Kozak, J. Ashot

    2016-01-01

    Lymphocyte proliferation in response to antigenic or mitogenic stimulation is a readily quantifiable phenomenon useful for testing immunomodulatory (i.e., immunosuppressive or immunostimulatory) chemical compounds and biologics. One of the earliest steps during mitogenesis is cell enlargement or blastogenic transformation, whereupon the cell volume increases before division. It is usually detectable in the first several hours of T-lymphocyte stimulation. Here, we describe a rapid method to quantify blastogenesis in T lymphocytes isolated from mouse spleens and human peripheral blood mononuclear cells (PBMCs) using an automated cell counter. Various commonly used proliferation assays for the most part are laborious and only reflect the overall population effect rather than individual cellular effects within a population. In contrast, the presented automated cell counter assay provides rapid, direct, and precise measurements of cell diameters that can be used for assessing the effectiveness of various mitogens and immunomodulatory drugs in vitro. PMID:28060354

  9. Curcuma longa attenuates carbon tetrachloride-induced oxidative stress in T-lymphocyte subpopulations.

    PubMed

    Abu-Rizq, H A; Mansour, Mohamed H; Afzal, Mohammad

    2015-01-01

    A comparison of crude curcuminoid extract and purified curcumin was made to evaluate the immunoprotective effect of Curcuma longa (turmeric) Zingiberaceae. Carbon tetrachloride (CCl4) induced selective cytolytic effects among immature (PNA(+)) thymocytes and peripheral helper (CD4(+)) T lymphocytes in the spleen were paralleled by a significant reduction in CD25, CD71, and Con A receptor expression. Treatment with curcumanoid crude extract, at two different doses, showed a significant restoration of lymphocyte viability and CD25, CD71, and Con A receptor expression in both immature (PNA+) thymocytes and splenic helper (CD4(+)) T lymphocytes. Turmeric crude extract, at both low and high dose, was found to be more efficient as compared to purified curcumin, suggesting synergistic effect of curcumin with other components of the crude extract.

  10. In vivo high spatiotemporal resolution visualization of circulating T lymphocytes in high endothelial venules of lymph nodes

    NASA Astrophysics Data System (ADS)

    Choe, Kibaek; Hwang, Yoonha; Seo, Howon; Kim, Pilhan

    2013-03-01

    Lymph nodes (LN) are major checkpoints for circulating T lymphocytes to recognize foreign antigens collected from peripheral tissue. High endothelial venule (HEV) in LN facilitates the effective transmigration of circulating T lymphocytes from the blood into LN. There have been many efforts to visualize T lymphocytes trafficking across HEV to understand the underlying mechanism. However, due to insufficient spatiotemporal resolution and the lack of an in vivo labeling method, clear visualization of dynamic behaviors of rapidly flowing T lymphocytes in HEV and their transmigration have been difficult. In this work, we adapted a custom-designed video-rate laser scanning confocal microscopy system to track individual flowing T lymphocytes in the HEV in real time in vivo. We demonstrate that the HEVs in LN can be clearly identified in vivo with its distinctive cuboidal morphology of endothelial cells fluorescently labeled by intravenously injected anti-CD31 antibody conjugated with Alexa fluorophore. By visualizing the adaptively transferred T lymphocytes, we successfully analyzed dynamic flowing behaviors of T lymphocytes and their transendothelial migration while interacting with the endothelial cells in HEV.

  11. Influenza B virus-specific CD8+ T-lymphocytes strongly cross-react with viruses of the opposing influenza B lineage.

    PubMed

    van de Sandt, Carolien E; Dou, YingYing; Vogelzang-van Trierum, Stella E; Westgeest, Kim B; Pronk, Mark R; Osterhaus, Albert D M E; Fouchier, Ron A M; Rimmelzwaan, Guus F; Hillaire, Marine L B

    2015-08-01

    Influenza B viruses fall in two antigenically distinct lineages (B/Victoria/2/1987 and B/Yamagata/16/1988 lineage) that co-circulate with influenza A viruses of the H3N2 and H1N1 subtypes during seasonal epidemics. Infections with influenza B viruses contribute considerably to morbidity and mortality in the human population. Influenza B virus neutralizing antibodies, elicited by natural infections or vaccination, poorly cross-react with viruses of the opposing influenza B lineage. Therefore, there is an increased interest in identifying other correlates of protection which could aid the development of broadly protective vaccines. blast analysis revealed high sequence identity of all viral proteins. With two online epitope prediction algorithms, putative conserved epitopes relevant for study subjects used in the present study were predicted. The cross-reactivity of influenza B virus-specific polyclonal CD8+ cytotoxic T-lymphocyte (CTL) populations obtained from HLA-typed healthy study subjects, with intra-lineage drift variants and viruses of the opposing lineage, was determined by assessing their in vitro IFN-γ response and lytic activity. Here, we show for the first time, to the best of our knowledge, that CTLs directed to viruses of the B/Victoria/2/1987 lineage cross-react with viruses of the B/Yamagata/16/1988 lineage and vice versa.

  12. Vaccination of rhesus monkeys with synthetic peptide in a fusogenic proteoliposome elicits simian immunodeficiency virus-specific CD8+ cytotoxic T lymphocytes

    PubMed Central

    1992-01-01

    An effective vaccine against the human immunodeficiency virus should be capable of eliciting both an antibody and a cytotoxic T lymphocyte (CTL) response. However, when viral proteins and peptides are formulated with traditional immunological adjuvants and inoculated via a route acceptable for use in humans, they have not been successful at eliciting virus-specific, major histocompatibility complex (MHC) class I-restricted CTL. We have designed a novel viral subunit vaccine by encapsulating a previously defined synthetic peptide CTL epitope of the simian immunodeficiency virus (SIV) gag protein within a proteoliposome capable of attaching to and fusing with plasma membranes. Upon fusing, the encapsulated contents of this proteoliposome can enter the MHC class I processing pathway through the cytoplasm. In this report, we show that after a single intramuscular vaccination, rhesus monkeys develop a CD8+ cell-mediated, MHC class I-restricted CTL response that recognizes the synthetic peptide immunogen. The induced CTL also demonstrate antiviral immunity by recognizing SIV gag protein endogenously processed by target cells infected with SIV/vaccinia recombinant virus. These results demonstrate that virus-specific, MHC class I-restricted, CD8+ CTL can be elicited by a safe, nonreplicating viral subunit vaccine in a primate model for acquired immune deficiency syndrome. Moreover, the proteoliposome vaccine formation described can include multiple synthetic peptide epitopes, and, thus, offers a simple means of generating antiviral cell-mediated immunity in a genetically heterogeneous population. PMID:1460429

  13. The development of in vitro mutagenicity testing systems using T-lymphocytes

    SciTech Connect

    Albertini, R.J.

    1992-05-01

    This work has focused on the development of in vitro T-cell mutation assays. Conditions have been defined to measure the in vitro induction of mutations at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus in human T-lymphocytes. This assay is a parallel to our in vivo hprt assay, in that the same cells are utilized. However, the in vitro assay allows for carefully controlled dose response studies. 21 refs., 16 figs., 13 tabs.

  14. Flow cytometric analysis of T lymphocyte proliferation in vivo by EdU incorporation.

    PubMed

    Sun, Xiaojing; Zhang, Chunpan; Jin, Hua; Sun, Guangyong; Tian, Yue; Shi, Wen; Zhang, Dong

    2016-12-01

    Monitoring T lymphocyte proliferation, especially in vivo, is essential for the evaluation of adaptive immune reactions. Flow cytometry-based proliferation assays have advantages in measuring cell division of different T lymphocyte subsets at the same time by multicolor labelling. In this study, we aimed to establish the use of 5-Ethynyl-2'-deoxyuridine (EdU) incorporation in vivo to monitor T lymphocyte proliferation by flow cytometry with an adoptive transfer model. We found that fixation followed by permeabilization preserved T cell surface antigens and had no obvious effects on the fluorescence intensity of APC, PE, PE-Cy7, FITC and PerCP-Cy5.5 when the concentration of the permeabilization reagents was optimized. However, the click reaction resulted in a significant decrease in the fluorescence intensity of PE and PE-Cy7, and surface staining after the click reaction improved the fluorescence intensity. Thus, an extra step of blocking with PBS with 3% FBS between the click reaction and cell surface staining is needed. Furthermore, the percentage of EdU-positive cells increased in a dose-dependent manner, and the saturated dose of EdU was 20mg/kg. Intraperitoneal and intravenous injection had no differences in lymphocyte proliferation detection with EdU in vivo. In addition, T cell proliferation measured by EdU incorporation was comparable to BrdU but was lower than CFSE labelling. In conclusion, we optimized the protocols for EdU administration in vivo and staining in vitro, providing a feasible method for the measurement of T lymphocyte proliferation with EdU incorporation by flow cytometry in vivo.

  15. A quartz nanopillar hemocytometer for high-yield separation and counting of CD4+ T lymphocytes

    NASA Astrophysics Data System (ADS)

    Kim, Dong-Joo; Seol, Jin-Kyeong; Wu, Yu; Ji, Seungmuk; Kim, Gil-Sung; Hyung, Jung-Hwan; Lee, Seung-Yong; Lim, Hyuneui; Fan, Rong; Lee, Sang-Kwon

    2012-03-01

    We report the development of a novel quartz nanopillar (QNP) array cell separation system capable of selectively capturing and isolating a single cell population including primary CD4+ T lymphocytes from the whole pool of splenocytes. Integrated with a photolithographically patterned hemocytometer structure, the streptavidin (STR)-functionalized-QNP (STR-QNP) arrays allow for direct quantitation of captured cells using high content imaging. This technology exhibits an excellent separation yield (efficiency) of ~95.3 +/- 1.1% for the CD4+ T lymphocytes from the mouse splenocyte suspensions and good linear response for quantitating captured CD4+ T-lymphoblasts, which is comparable to flow cytometry and outperforms any non-nanostructured surface capture techniques, i.e. cell panning. This nanopillar hemocytometer represents a simple, yet efficient cell capture and counting technology and may find immediate applications for diagnosis and immune monitoring in the point-of-care setting.We report the development of a novel quartz nanopillar (QNP) array cell separation system capable of selectively capturing and isolating a single cell population including primary CD4+ T lymphocytes from the whole pool of splenocytes. Integrated with a photolithographically patterned hemocytometer structure, the streptavidin (STR)-functionalized-QNP (STR-QNP) arrays allow for direct quantitation of captured cells using high content imaging. This technology exhibits an excellent separation yield (efficiency) of ~95.3 +/- 1.1% for the CD4+ T lymphocytes from the mouse splenocyte suspensions and good linear response for quantitating captured CD4+ T-lymphoblasts, which is comparable to flow cytometry and outperforms any non-nanostructured surface capture techniques, i.e. cell panning. This nanopillar hemocytometer represents a simple, yet efficient cell capture and counting technology and may find immediate applications for diagnosis and immune monitoring in the point-of-care setting

  16. Treatment with Interleukin-7 Restores Host Defense against Pneumocystis in CD4+ T-Lymphocyte-Depleted Mice

    PubMed Central

    Samuelson, D. R.; Assouline, B.; Morre, M.; Shellito, J. E.

    2015-01-01

    Pneumocystis pneumonia (PCP) is a major cause of morbidity and mortality in patients with HIV infection. CD4+ T lymphocytes are critical for host defense against this infection, but in the absence of CD4+ T lymphocytes, CD8+ T lymphocytes may provide limited host defense. The cytokine interleukin-7 (IL-7) functions to enhance lymphocyte proliferation, survival, and recruitment of immune cells to sites of infection. However, there is little known about the role of IL-7 in PCP or its potential use as an immunotherapeutic agent. We hypothesized that treatment with recombinant human IL-7 (rhIL-7) would augment host defense against Pneumocystis and accelerate pathogen clearance in CD4-depleted mice. Control and CD4-depleted mice were infected with Pneumocystis, and rhIL-7 was administered via intraperitoneal injection. Our studies indicate that endogenous murine IL-7 is part of the normal host response to Pneumocystis murina and that administration of rhIL-7 markedly enhanced clearance of Pneumocystis in CD4-depleted mice. Additionally, we observed increased recruitment of CD8+ T lymphocytes to the lungs and decreased apoptosis of pulmonary CD8+ T lymphocytes in rhIL-7-treated animals compared to those in untreated mice. The antiapoptotic effect of rhIL-7 was associated with increased levels of Bcl-2 protein in T lymphocytes. rhIL-7 immunotherapy in CD4-depleted mice also increased the number of gamma interferon (IFN-γ)-positive CD8+ central memory T lymphocytes in the lungs. We conclude that rhIL-7 has a potent therapeutic effect in the treatment of murine Pneumocystis pneumonia in CD4-depleted mice. This therapeutic effect is mediated through enhanced recruitment of CD8+ T cells and decreased apoptosis of lung T lymphocytes, with a preferential action on central memory CD8+ T lymphocytes. PMID:26483405

  17. [Effect of arginine supplementation on T-lymphocyte function in burn patients].

    PubMed

    Lu, S L

    1993-09-01

    It is well accepted that nutritional support improves the immunologic functions in burn patients. Arginine has been demonstrated to have tissue--specific properties which influence certain components of the immune system. A series of experiments were carried out in this study, in order to evaluate the immune effect of arginine on T lymphocyte functions in burn patients. Two groups of burn patients with comparable clinical protocol receiving same nutritional administration except the amount of arginine in the nutrients were studied. In one group, 2% of energy supplied by arginine was added in their nutrients, while, the control group received 2% of energy from amino acid compounds instead. The T lymphocyte immune parameters were determined on days 3, 7, 14, 21 and 28 postburn. The data showed that the 2% of total energy supplied by arginine was found to significantly enhance the T lymphocyte response to PHA, CD4 phenotype expression, CD4/CD8 ratio, IL-2 production and IL-2 receptor expression, as compared with the control group. It suggests arginine should become one of the most important nutrients supplied to burn patients.

  18. T-lymphocyte passive deformation is controlled by unfolding of membrane surface reservoirs

    PubMed Central

    Guillou, Lionel; Babataheri, Avin; Saitakis, Michael; Bohineust, Armelle; Dogniaux, Stéphanie; Hivroz, Claire; Barakat, Abdul I.; Husson, Julien

    2016-01-01

    T-lymphocytes in the human body routinely undergo large deformations, both passively, when going through narrow capillaries, and actively, when transmigrating across endothelial cells or squeezing through tissue. We investigate physical factors that enable and limit such deformations and explore how passive and active deformations may differ. Employing micropipette aspiration to mimic squeezing through narrow capillaries, we find that T-lymphocytes maintain a constant volume while they increase their apparent membrane surface area upon aspiration. Human resting T-lymphocytes, T-lymphoblasts, and the leukemic Jurkat T-cells all exhibit membrane rupture above a critical membrane area expansion that is independent of either micropipette size or aspiration pressure. The unfolded membrane matches the excess membrane contained in microvilli and membrane folds, as determined using scanning electron microscopy. In contrast, during transendothelial migration, a form of active deformation, we find that the membrane surface exceeds by a factor of two the amount of membrane stored in microvilli and folds. These results suggest that internal membrane reservoirs need to be recruited, possibly through exocytosis, for large active deformations to occur. PMID:27605708

  19. Activation of T lymphocytes and the role of the adapter LAT.

    PubMed

    Aguado, Enrique; Martínez-Florensa, Mario; Aparicio, Pedro

    2006-12-01

    The adapter molecule LAT (Linker for the Activation of T cells) is a membrane protein that becomes phosphorylated on conserved tyrosine residues upon TCR/CD3 complex engagement in T lymphocytes. Tyrosine phosphorylation of this adapter recruits to the membrane many signaling proteins through the interaction with the phosphotyrosine binding domains of these proteins, allowing the activation of several intracellular signaling pathways. Initial studies performed in T cell lines suggested that the adapter LAT acts primarily as a platform for the distribution of activation signals coming from the TCR/CD3 complex, and the phenotype of LAT deficient mice, in which T cell development is arrested at an early stage, supported this "activatory" function. However, the analysis of several knock-in mice strains in which some tyrosine residues have been mutated, has revealed the development of lymphoproliferative disorders caused by polyclonal T lymphocytes producing high titers of T helper-type 2 (T(H)2) cytokines. Very recently, it has been demonstrated that raft localization of LAT is altered in anergic T lymphocytes. Therefore, LAT show unexpected regulatory functions in T cell development and homeostasis.

  20. Defective cAMP-dependent phosphorylation of intact T lymphocytes in active systemic lupus erythematosus.

    PubMed Central

    Hasler, P; Schultz, L A; Kammer, G M

    1990-01-01

    The present study was undertaken to establish whether cAMP-dependent phosphorylation of endogenous substrates is impaired in T lymphocytes from subjects with active systemic lupus erythematosus (SLE). In normal human T lymphocytes, the cell-permeable cAMP analog, N6,O2'-dibutyryladenosine 3',5'-cyclic monophosphate, induced phosphorylation of substrates with molecular masses of 17.5, 23/25, 33.5 kDa on one-dimensional SDS/PAGE. Maximal phosphorylation occurred at 60 min. In contrast to healthy T cells, the extent of substrate phosphorylation achieved in active SLE T cells (n = 8) was only 15% at 60 min in the 17.5-kDa substrate, 21% in the 23/25-kDa substrate, and 9% in the 33.5-kDa substrate. The rheumatic disease controls (rheumatoid arthritis; primary Sjögren syndrome; n = 8) exhibited a mean 72%, 124%, and 85%, respectively, of phosphorylation observed in healthy T cells. Because the only known mechanism by which cAMP acts is via cAMP-dependent protein kinase (protein kinase A), these data raise the possibility of a defect at the level of this kinase in SLE T lymphocytes. Images PMID:2155428

  1. Differential transforming activity of the retroviral Tax oncoproteins in human T lymphocytes.

    PubMed

    Ren, Tong; Cheng, Hua

    2013-01-01

    Human T cell leukemia virus type 1 and type 2 (HTLV-1 and -2) are two closely related retroviruses. HTLV-1 causes adult T cell leukemia and lymphoma, whereas HTLV-2 infection is not etiologically linked to human disease. The viral genomes of HTLV-1 and -2 encode highly homologous transforming proteins, Tax-1 and Tax-2, respectively. Tax-1 is thought to play a central role in transforming CD4+ T lymphocytes. Expression of Tax-1 is crucial for promoting survival and proliferation of virally infected human T lymphocytes and is necessary for initiating HTLV-1-mediated oncogenesis. In transgenic mice and humanized mouse model, Tax-1 has proven to be leukemogenic. Although Tax-1 is able to efficiently transform rodent fibroblasts and to induce lymphoma in mouse model, it rarely transforms primary human CD4+ T lymphocytes. In contrast, Tax-2 efficiently immortalizes human CD4+ T cells though it exhibits a lower transforming activity in rodent cells as compared to Tax-1. We here discuss our recent observation and views on the differential transforming activity of Tax-1 and Tax-2 in human T cells.

  2. Neochromine S5 improves contact hypersensitivity through a selective effect on activated T lymphocytes.

    PubMed

    Gao, Zhe; Ma, Yuxiang; Zhao, Dan; Zhang, Xiong; Zhou, Hang; Liu, Hailiang; Zhou, Yang; Wu, Xuefeng; Shen, Yan; Sun, Yang; Li, Jianxin; Wu, Xudong; Xu, Qiang

    2014-11-15

    Strategy on activated T cells is an effective treatment for T cell mediated diseases. By using a synthesized chromone derivative, we examined its effects on the activated T cells. This compound, (Z)-1,3-dihydroxy-9-methyl-13H-benzo[b]chromeno[3,2-f][1,4]oxazepin-13-one (neochromine S5), exhibited immunosuppressive activity in vitro and in vivo. Interestingly, neochromine S5 selectively inhibited proliferation and induced apoptosis in T lymphocytes activated by concanavalin A (Con A) in a dose-dependent manner but not in naïve T lymphocytes, distinct from quercetin. This compound triggered mitochondrial apoptotic pathway including cleavage of caspase 3, caspase 9 and PARP, downregulation of bcl-2 and release of cytochrome c in activated T cells, but did not affect ER stress or Fas signals. In addition, neochromine S5 downregulated the expression of CD25 and CD69 and the production of inflammatory cytokines, including TNFα, IFNγ and IL-2, improved ear swelling in mice with contact hypersensitivity, reduced CD4(+) T cells infiltration, and increased apoptosis of isolated T lymphocytes from peripheral lymph nodes. Moreover, neochromine S5 showed no effect on the weight of mice and their immune organs, while dexamethasone caused a significant weight loss. Taken together, our results suggest that neochromine S5 exerts a unique anti-inflammatory activity mainly through a selective effect on activated T cells, which is different from the current immunosuppressant, dexamethasone.

  3. Increased radiosensitivity of a subpopulation of T-lymphocyte progenitors from patients with Fanconi's anemia

    SciTech Connect

    Knox, S.J.; Wilson, F.D.; Greenberg, B.R.; Shifrine, M.; Rosenblatt, L.S.; Reeves, J.D.; Misra, H.

    1981-06-01

    In vitro radiation survival of peripheral blood T lymphocytes was studied in 15 clinically normal adults and 4 patients with Fanconi's anemia. Tritiated thymidine incorporation in a whole blood lymphocyte stimulation test (LST) and a newly developed whole blood T-lymphocyte colony assay were used to measure lymphocyte blastogenesis and colony formation in response to phytohemagglutinin (PHA) or concanavalin-A (Con-A) stimulation. Lymphocyte colony formation was found to be consistently more sensitive than the LST for detection of low-level radiation effects using both normal cells and lymphocytes from Fanconi's anemia patients. Lymphocytes from patients with Fanconi's anemia were significantly more sensitive to in vitro x irradiation than lymphocytes from clinically normal individuals as measured by their ability to divide when stimulated by PHA in the LST and colony formation assay. No significant difference in the radiosensitivity of the Con-A response was observed between the two groups. The PHA-responsive T-lymphocyte subpopulation in Fanconi's anemia patients appears to be intrinsically defective. The nature of this defect, significance in the disease process, and relevancy of these findings to the establishment of radiation protection standards are discussed.

  4. Increased radiosensitivity of a subpopulation ot T-lymphocyte progenitors from patients with Fanconi's anemia

    SciTech Connect

    Knox, S.J.; Wilson, F.D.; Greenberg, B.R.; Shifrine, M.; Rosenblatt, L.S.; Reeves, J.D.; Misra, H.

    1981-06-01

    In vitro radiation survival of peripheral blood T lymphocytes was studied in 15 clinically normal adults and 4 patients with Fanconi's anemia. Tritiated thymidine incorporation in a whole blood lymphocyte stimulation test (LST) and a newly developed whole blood T-lymphocyte colony assay were used to measure lymphocyte blastogenesis and colony formation in response to phytohemagglutinin (PHA) or concanavalin-A (Con-A) stimulation. Lymphocyte colony formation was found to be consistently more sensitive than the LST for detection of low-level radiation effects using both normal cells and lymphocytes from Fanconi's anemia patients. Lymphocytes from patients with Fanconi's anemia were significantly more sensitive to in vitro x-irradiation than lymphocytes from clinically normal individuals as measured by their ability to divide when stimulated by PHA in the LST (patients, D37 . 198 R; normals, D37 . 309 R, p . 0.057) and colony formation assay (patients, D37 . 53 R; normals, D37 . 109 R, p . 0.016). No significant difference in the radiosensitivity of the Con-A response was observed between the two groups. The PHA-responsive T-lymphocyte subpopulation in Fanconi's anemia patients appears to be intrinsically defective. The nature of this defect, significance in the disease process, and relevancy of these findings to the establishment of radiation protection standards are discussed.

  5. Fluoxetine suppresses calcium signaling in human T lymphocytes through depletion of intracellular calcium stores.

    PubMed

    Gobin, V; De Bock, M; Broeckx, B J G; Kiselinova, M; De Spiegelaere, W; Vandekerckhove, L; Van Steendam, K; Leybaert, L; Deforce, D

    2015-09-01

    Selective serotonin reuptake inhibitors, such as fluoxetine, have recently been shown to exert anti-inflammatory and immunosuppressive effects. Although the effects on cytokine secretion, proliferation and viability of T lymphocytes have been extensively characterized, little is known about the mechanism behind these effects. It is well known that Ca(2+) signaling is an important step in the signaling transduction pathway following T cell receptor activation. Therefore, we investigated if fluoxetine interferes with Ca(2+) signaling in Jurkat T lymphocytes. Fluoxetine was found to suppress Ca(2+) signaling in response to T cell receptor activation. Moreover, fluoxetine was found to deplete intracellular Ca(2+) stores, thereby leaving less Ca(2+) available for release upon IP3- and ryanodine-receptor activation. The Ca(2+)-modifying effects of fluoxetine are not related to its capability to block the serotonin transporter, as even a large excess of 5HT did not abolish the effects. In conclusion, these data show that fluoxetine decreases IP3- and ryanodine-receptor mediated Ca(2+) release in Jurkat T lymphocytes, an effect likely to be at the basis of the observed immunosuppression.

  6. Accumulation of eosinophils and T-lymphocytes in the lungs after exposure to pinewood dust.

    PubMed

    Gripenbäck, S; Lundgren, L; Eklund, A; Lidén, C; Skare, L; Tornling, G; Grunewald, J

    2005-01-01

    Exposure to wood dust within the woodworking industry has been shown to cause a variety of respiratory disorders. The aim of this study was to investigate the cellular effects in bronchoalveolar lavage (BAL) fluid and peripheral blood from healthy individuals exposed to pinewood dust. Eleven healthy volunteers were exposed to pinewood dust for 1 h in a whole-body exposure chamber. BAL fluid and blood cells were differentially counted and the expression of activation, adhesion and subset markers on alveolar macrophages and T-lymphocytes was determined 2-6 weeks before and 20 h after the exposure. Following pinewood dust exposure, the total BAL fluid cell concentration increased from 81.4 (64.1-97.5) x 10(6) cells x L(-1) (median (interquartile range)) to 195.3 (154.6-341.2) x 10(6) cells x L(-1). The BAL fluid T-lymphocyte concentration increased from 3.8% (3.5-6.5%) to 7.6% (4.9-11.2%), and BAL fluid eosinophil concentration from 0.0% (0.0-0.2%) to 1.8% (0.6-3.5%). Inhalation of pinewood dust leads to the recruitment of inflammatory cells to the airways of healthy individuals. The increase in numbers of eosinophils, T-lymphocytes and mast cells, i.e. cells of crucial importance to airway inflammation, in the lungs may be related to the increased risk of developing respiratory disorders among woodworkers.

  7. Autoimmune B-cell lymphopenia after successful adoptive therapy with telomerase-specific T lymphocytes.

    PubMed

    Ugel, Stefano; Scarselli, Elisa; Iezzi, Manuela; Mennuni, Carmela; Pannellini, Tania; Calvaruso, Francesco; Cipriani, Barbara; De Palma, Raffaele; Ricci-Vitiani, Lucia; Peranzoni, Elisa; Musiani, Piero; Zanovello, Paola; Bronte, Vincenzo

    2010-02-18

    Telomerase reverse transcriptase (TERT) is a good candidate for cancer immunotherapy because it is overexpressed in 85% of all human tumors and implicated in maintenance of the transformed phenotype. TERT-based cancer vaccines have been shown to be safe, not inducing any immune-related pathology, but their impact on tumor progression is modest. Here we show that adoptive cell therapy with the use of high-avidity T lymphocytes reactive against telomerase can control the growth of different established tumors. Moreover, in transgenic adenocarcinoma mouse prostate mice, which develop prostate cancer, TERT-based adoptive cell therapy halted the progression to more aggressive and poorly differentiated tumors, significantly prolonging mouse survival. We also demonstrated that human tumors, including Burkitt lymphoma, and human cancer stem cells, are targeted in vivo by TERT-specific cytotoxic T lymphocytes. Effective therapy with T cells against telomerase, different from active vaccination, however, led to autoimmunity marked by a consistent, although transient, B-cell depletion in primary and secondary lymphoid organs, associated with alteration of the spleen cytoarchitecture. These results indicate B cells as an in vivo target of TERT-specific cytotoxic T lymphocytes during successful immunotherapy.

  8. L-arginine metabolism in myeloid cells controls T-lymphocyte functions.

    PubMed

    Bronte, Vincenzo; Serafini, Paolo; Mazzoni, Alessandra; Segal, David M; Zanovello, Paola

    2003-06-01

    Although current attention has focused on regulatory T lymphocytes as suppressors of autoimmune responses, powerful immunosuppression is also mediated by a subset of myeloid cells that enter the lymphoid organs and peripheral tissues during times of immune stress. If these myeloid suppressor cells (MSCs) receive signals from activated T lymphocytes in the lymphoid organs, they block T-cell proliferation. MSCs use two enzymes involved in arginine metabolism to control T-cell responses: inducible nitric oxide synthase (NOS2), which generates nitric oxide (NO) and arginase 1 (Arg1), which depletes the milieu of arginine. Th1 cytokines induce NOS2, whereas Th2 cytokines upregulate Arg1. Induction of either enzyme alone results in a reversible block in T-cell proliferation. When both enzymes are induced together, peroxynitrites, generated by NOS2 under conditions of limiting arginine, cause activated T lymphocytes to undergo apoptosis. Thus, NOS2 and Arg1 might act separately or synergistically in vivo to control specific types of T-cell responses, and selective antagonists of these enzymes might prove beneficial in fighting diseases in which T-cell responses are inappropriately suppressed. This Opinion is the second in a series on the regulation of the immune system by metabolic pathways.

  9. Heterogeneity of thymic epithelial cells in promoting T-lymphocyte differentiation in vivo.

    PubMed Central

    Gutierrez, J C; Palacios, R

    1991-01-01

    To study in vivo the contribution of different thymic epithelial cells to T-lymphocyte differentiation, we have established several nontransformed thymic epithelial cell lines and developed an in vivo assay, not involving exposure to drugs or radiation, that permitted us to study the capacity of these epithelial lines to support T-cell differentiation. We found that cell lines EA2 and ET, which express markers of cortical epithelial cells, produce interleukin 7 mRNA and after being injected into the spleens of young athymic nude mice support in vivo generation of CD4+CD8- T-cell receptor alpha beta+ T lymphocytes (ET line) or both CD4+CD8- and CD4-CD8+ T-cell receptor alpha beta+ T cells (EA2 line). Both cell lines also supported generation of T-cell receptor gamma delta+ T cells but appear not to support development of double-positive (CD4+CD8+) cells. One cell line, EB3, which expresses markers of medullary epithelial cells, produces interleukin 1 alpha RNA transcripts but does not support T-lymphocyte differentiation. The results provide direct evidence for functional heterogeneity of thymic epithelial cells in vivo and show the involvement of different cortical epithelial cells in the differentiation of T-cell progenitors into distinct thymocyte subsets. Images PMID:1988959

  10. Structural basis of cross-allele presentation by HLA-A*0301 and HLA-A*1101 revealed by two HIV-derived peptide complexes.

    PubMed

    Zhang, Shihong; Liu, Jun; Cheng, Hao; Tan, Shuguang; Qi, Jianxun; Yan, Jinghua; Gao, George F

    2011-10-01

    Human leukocyte antigens (HLA) are initially classified by serotyping but recently can be re-grouped by their peptide-presentation characteristics into supertypes. Both HLA-A*0301 and HLA-A*1101 are grouped into A3 supertype. Although a number of cross-presented T cell epitopes of HLA-A*0301 and HLA-A*1101 have been identified, the molecular mechanisms of cross-presentation remain elusive. Herein, the structures of HLA-A*0301 with two HIV-derived immunodominant T cell epitopes were solved and their characteristics in comparison with HLA-A*1101 presenting the same peptides were analyzed. The comparable structures of HLA-A*0301 and HLA-A*1101 with subtle differences illustrate the common modes of cross-presented peptides and the strict HLA-restriction of T cell receptor (TCR)-recognition.

  11. Characterization of T-lymphocytes in the anterior uvea of eyes with chronic equine recurrent uveitis.

    PubMed

    Gilger, B C; Malok, E; Cutter, K V; Stewart, T; Horohov, D W; Allen, J B

    1999-10-01

    Equine recurrent uveitis (ERU), a chronic, recurrent inflammation primarily of the anterior uveal tract, is the most common cause of blindness in horses. Recently, T-lymphocytes have been found to be the most numerous cell type to infiltrate the anterior uveal of horses with ERU. In the present study, we characterized the T-lymphocyte population in the anterior uveal tract of eyes of horses with chronic ERU by evaluating the microscopic appearance (histopathologic features), the T-lymphocyte subsets, and the relative levels and amounts of T-lymphocyte cytokine mRNA in the anterior uvea. Seven inflamed eyes (from six horses with chronic ERU) and 5 normal eyes (from five horses with nonocular problems) were studied. After clinical examination, the eyes were removed, ocular fluids were aspirated, and anterior uveal tissues (iris and ciliary body) were processed for histologic and molecular (RNA isolation) analyses. Histologic examination by hematoxylin and eosin (H and E) staining and immunohistochemistry evaluating T-lymphocyte subsets (anti-CD4, CD8, CD5) were performed for each sample. RNA samples were analyzed for levels of messenger (m) RNA specific for interleukin (IL)-2, 4, and interferon-gamma (IFNgamma) by quantitative reverse transcriptase polymerase chain reaction (QRT-PCR). Eyes with ERU exhibited characteristic clinical signs, including corneal edema, aqueous flare, posterior synechia, corpora nigra degeneration, and cataract formation. Histologically, infiltration of the uveal tract with lymphocytes, plasma cells, and macrophages was most evident in the ciliary body and base of the iris. Loss of tissue structure (destruction) was most evident in the ciliary processes. Infiltrating lymphocytes were predominantly CD4+ T-cells (e.g. 48% CD4+ and 18% CD8+ in the ciliary body stroma), as determined by immunohistochemistry. Few inflammatory cells were observed in the normal eyes. The QRT-PCR results revealed increased transcription of IL-2 and IFNgamma and low

  12. PD-1 function in apoptosis of T lymphocytes in canine visceral leishmaniasis.

    PubMed

    Chiku, Vanessa Marim; Silva, Kathlenn Liezbeth Oliveira; de Almeida, Breno Fernando Martins; Venturin, Gabriela Lovizutto; Leal, Aline Aparecida Correa; de Martini, Cleber Costa; de Rezende Eugênio, Flavia; Dos Santos, Paulo Sergio Patto; de Lima, Valéria Marçal Felix

    2016-08-01

    Dogs infected with Leishmania infantum have a reduced number of T lymphocytes. PD-1 (Programmed cell death 1) a new member of the B7-CD28 family that is expressed by immune cells, and its binding to PD-L1 (CD274) or PD-L2 (CD273) induces the deactivation or apoptosis of T cells. This study aimed to evaluate the expression of PD-1 and its ligands, as well as blocking in the induction of apoptosis in T lymphocytes, TNF-α, IL-4 and nitric oxide production by leucokocytes from PBMC and spleen and the parasite load in dogs with visceral leishmaniasis (VL). Our results showed that the expression of PD1 and its ligands was increased in CD3(+) T cells and CD21(+) B lymphocytes within the peripheral blood and splenic mononuclear cells of dogs with VL. In peripheral blood monocytes, only PD-1 ligands exhibited increased expression; however, in spleen macrophages, increased expression of both PD-1 and its ligands was observed. Levels of apoptosis in peripheral blood and splenic T lymphocytes were higher in dogs with VL compared to healthy dogs. Blocking monoclonal antibodies to PD-1 and its ligands in the culture of mononuclear cells from the peripheral blood and spleen decreased the amount of CD3(+) T lymphocyte apoptosis. The concentration of nitric oxide, TNF-α and IL-4 increased in the culture supernatants of peripheral blood mononuclear cells treated with a blocking monoclonal antibody against PD-1. The TNF-α concentration increased in the culture supernatants of splenic cells following all treatments with antibodies blocking PD-1 and its ligands; however, the amount of IL-4 increased only in the presence of a PD-1 blocking agent. Treatment with a PD-1 blocking monoclonal antibody in the mononuclear peripheral blood of dogs with VL reduced the parasite burden while increased TNF-α. We conclude that in canine visceral leishmaniasis, PD-1 and its ligands are involved in the induction of T lymphocyte apoptosis and in regulating the production of nitric oxide, TNF

  13. CD4⁺CD28null T lymphocytes resemble CD8⁺CD28null T lymphocytes in their responses to IL-15 and IL-21 in HIV-infected patients.

    PubMed

    Echeverría, Ainara; Moro-García, Marco A; Asensi, Víctor; Cartón, José A; López-Larrea, Carlos; Alonso-Arias, Rebeca

    2015-09-01

    HIV-infected individuals suffer from accelerated immunologic aging. One of the most prominent changes during T lymphocyte aging is the accumulation of CD28(null) T lymphocytes, mainly CD8(+) but also CD4(+) T lymphocytes. Enhancing the functional properties of these cells may be important because they provide antigen-specific defense against chronic infections. The objective of this study was to compare the responses of CD4(+)CD28(null) and CD8(+)CD28(null) T lymphocytes from HIV-infected patients to the immunomodulatory effects of cytokines IL-15 and IL-21. We quantified the frequencies of CD4(+)CD28(null) and CD8(+)CD28(null) T lymphocytes in peripheral blood from 110 consecutive, HIV-infected patients and 25 healthy controls. Patients showed increased frequencies of CD4(+)CD28(null) and CD8(+)CD28(null). Both subsets were positively correlated to each other and showed an inverse correlation with the absolute counts of CD4(+) T lymphocytes. Higher frequencies of HIV-specific and CMV-specific cells were found in CD28(null) than in CD28(+) T lymphocytes. Activation of STAT5 by IL-15 and STAT3 by IL-21 was higher in CD28(null) compared with CD28(+) T lymphocytes. Proliferation, expression of CD69, and IFN-γ production in CD28(null) T lymphocytes were increased after treatment with IL-15, and IL-21 potentiated most of those effects. Nevertheless, IL-21 alone reduced IFN-γ production in response to anti-CD3 stimulation but increased CD28 expression, even counteracting the inhibitory effect of IL-15. Intracytoplasmic stores of granzyme B and perforin were increased by IL-15, whereas IL-21 and simultaneous treatment with the 2 cytokines also significantly enhanced degranulation in CD4(+)CD28(null) and CD8(+)CD28(null) T lymphocytes. IL-15 and IL-21 could have a role in enhancing the effector response of CD28(null) T lymphocytes against their specific chronic antigens in HIV-infected patients.

  14. A novel multi-epitope peptide vaccine against cancer: an in silico approach.

    PubMed

    Nezafat, Navid; Ghasemi, Younes; Javadi, Gholamreza; Khoshnoud, Mohammad Javad; Omidinia, Eskandar

    2014-05-21

    Cancer immunotherapy has an outstanding position in cancer prevention and treatment. In this kind of therapy, the immune system is activated to eliminate cancerous cells. Multi-epitope peptide cancer vaccines are manifesting as the next generation of cancer immunotherapy. In the present study, we have implemented various strategies to design an efficient multi-epitope vaccine. CD8+ cytolytic T lymphocytes (CTLs) epitopes, which have a pivotal role in cellular immune responses, helper epitopes and adjuvant, are three crucial components of peptide vaccine. CTL epitopes were determined from two high immunogenic protein Wilms tumor-1 (WT1) and human papillomavirus (HPV) E7 by various servers, which apply different algorithms. CTL epitopes were linked together by AAY and HEYGAEALERAG motifs to enhance epitope presentation. Pan HLA DR-binding epitope (PADRE) peptide sequence and helper epitopes, which have defined from Tetanus toxin fragment C (TTFrC) by various servers, were used to induce CD4+ helper T lymphocytes (HTLs) responses. Additionally, helper epitopes were conjugated together via GPGPG motifs that stimulate HTL immunity. Heparin-Binding Hemagglutinin (HBHA), a novel TLR4 agonist was employed as an adjuvant to polarize CD4+ T cells toward T-helper 1 to induce strong CTL responses. Moreover, the EAAAK linker was introduced to N and C terminals of HBHA for efficient separation. 3D model of protein was generated and predicted B cell epitopes were determined from the surface of built structure. Our protein contains several linear and conformational B cell epitopes, which suggests the antibody triggering property of this novel vaccine. Hence, our final protein can be used for prophylactic or therapeutic usages, because it can potentially stimulate both cellular and humoral immune responses.

  15. Contribution of CD8 T lymphocytes to the immuno-pathogenesis of multiple sclerosis and its animal models

    PubMed Central

    Mars, Lennart T.; Saikali, Philippe; Liblau, Roland S.; Arbour, Nathalie

    2016-01-01

    Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by multi-focal demyelination, axonal loss, and immune cell infiltration. Numerous immune mediators are detected within MS lesions, including CD4+ and CD8+ T lymphocytes suggesting that they participate in the related pathogenesis. Although CD4+ T lymphocytes are traditionally considered the main actors in MS immunopathology, multiple lines of evidence suggest that CD8+ T lymphocytes are also implicated in the pathogenesis. In this review, we outline the recent literature pertaining to the potential roles of CD8+ T lymphocytes both in MS and its animal models. The CD8+ T lymphocytes detected in MS lesions demonstrate characteristics of activated and clonally expanded cells supporting the notion that these cells actively contribute to the observed injury. Moreover, several experimental in vivo models mediated by CD8+ T lymphocytes recapitulate important features of the human disease. Whether the CD8+ T cells can induce or aggravate tissue destruction in the CNS needs to be fully explored. Strengthening our understanding of the pathogenic potential of CD8+ T cells in MS should provide promising new avenues for the treatment of this disabling inflammatory disease. PMID:20637863

  16. GTPase of the Immune-Associated Nucleotide Protein 5 Regulates the Lysosomal Calcium Compartment in T Lymphocytes

    PubMed Central

    Serrano, Daniel; Ghobadi, Farnaz; Boulay, Guylain; Ilangumaran, Subburaj; Lavoie, Christine; Ramanathan, Sheela

    2017-01-01

    T lymphocytes from Gimap5lyp/lyp rats carrying a recessive mutation in the GTPase of immune-associated protein 5 (Gimap5) gene undergo spontaneous apoptosis. Molecular mechanisms underlying this survival defect are not yet clear. We have shown that Gimap5lyp/lyp T lymphocytes display reduced calcium influx following T cell antigen receptor (TCR) stimulation that was associated with impaired buffering of calcium by mitochondria. Here, we investigated the subcellular localization of GIMAP5 and its influence on Ca2+ response in HEK293T cells and T lymphocytes. The more abundantly expressed GIMAP5v2 localizes to the lysosome and certain endosomal vesicles. Gimap5lyp/lyp T lymphocytes showed increased accumulation of calcium in the lysosomes as evidenced by Gly-Phe β-naphthylamide (GPN) triggered Ca2+ release. As a corollary, GPN-induced Ca2+ flux was decreased in HEK293T cells expressing GIMAP5v2. Strikingly, TCR stimulation of rat, mouse, and human T lymphocytes increased lysosomal calcium content. Overall, our findings show that lysosomes modulate cellular Ca2+ response during T cell activation and that GIMAP5 regulates the lysosomal Ca2+ compartment in T lymphocytes. PMID:28223986

  17. Cell surface Glut1 levels distinguish human CD4 and CD8 T lymphocyte subsets with distinct effector functions

    PubMed Central

    Cretenet, Gaspard; Clerc, Isabelle; Matias, Maria; Loisel, Severine; Craveiro, Marco; Oburoglu, Leal; Kinet, Sandrina; Mongellaz, Cédric; Dardalhon, Valérie; Taylor, Naomi

    2016-01-01

    CD4 and CD8 T lymphocyte activation requires the generation of sufficient energy to support new biosynthetic demands. Following T cell receptor (TCR) engagement, these requirements are met by an increased glycolysis, due, at least in part, to induction of the Glut1 glucose transporter. As Glut1 is upregulated on tumor cells in response to hypoxia, we assessed whether surface Glut1 levels regulate the antigen responsiveness of human T lymphocytes in both hypoxic and atmospheric oxygen conditions. Notably, Glut1 upregulation in response to TCR stimulation was significantly higher in T lymphocytes activated under hypoxic as compared to atmospheric oxygen conditions. Furthermore, TCR-stimulated human T lymphocytes sorted on the basis of Glut1-Lo and Glut1-Hi profiles maintained distinct characteristics, irrespective of the oxygen tension. While T cells activated in hypoxia divided less than those activated in atmospheric oxygen, Glut1-Hi lymphocytes exhibited increased effector phenotype acquisition, augmented proliferation, and an inverted CD4/CD8 ratio in both oxygen conditions. Moreover, Glut1-Hi T lymphocytes exhibited a significantly enhanced ability to produce IFN-γ and this secretion potential was completely dependent on continued glycolysis. Thus, Glut1 surface levels identify human T lymphocytes with distinct effector functions in both hypoxic and atmospheric oxygen tensions. PMID:27067254

  18. CD39 Expression on T Lymphocytes Correlates With Severity of Disease in Patients With Chronic Lymphocytic Leukemia

    PubMed Central

    Pulte, Dianne; Furman, Richard R.; Broekman, M. Johan; Drosopoulos, Joan H. F.; Ballard, Harold S.; Olson, Kim E.; Kizer, Jorge R.; Marcus, Aaron J.

    2012-01-01

    Introduction Chronic lymphocytic leukemia (CLL) is a B-cell disorder, but it is also associated with abnormalities in T-lymphocyte function. In this study we examine changes in T-lymphocyte CD39 and CD73 expression in patients with CLL. Methods Blood samples were drawn from 34 patients with CLL and 31 controls. The cells were stained for CD3, CD4, CD8, CD19, CD39, and CD73 and analyzed by flow cytometry. Results Overall, patients with CLL had a higher percentage of CD39+ T lymphocytes than did controls. The percentage of cells expressing CD39 was higher in both CD4+ cells and CD8+ cells. Higher CD3/CD39 expression was associated with a later disease stage. No correlations between T-lymphocyte CD39 levels and CD38 or Zap-70 expression were observed. In contrast, the percentage of T lymphocytes and B lymphocytes that expressed CD73 was decreased in patients with CLL. Average B-lymphocyte CD73 expression was decreased in CLL because the majority of CLL clones were CD73. However a minority of CLL clones were CD73+, and patients with CD73+ clones tended to have earlier stage disease. Conclusion T-lymphocyte CD39 and CD73 expression may be useful prognostic markers in patients with CLL. Expression of CD73 on the malignant cell population in CLL may be a marker of better prognosis. PMID:21816376

  19. Variant antigenic peptide promotes cytotoxic T lymphocyte adhesion to target cells without cytotoxicity

    PubMed Central

    Shotton, David M.; Attaran, Amir

    1998-01-01

    Timelapse video microscopy has been used to record the motility and dynamic interactions between an H-2Db-restricted murine cytotoxic T lymphocyte clone (F5) and Db-transfected L929 mouse fibroblasts (LDb) presenting normal or variant antigenic peptides from human influenza nucleoprotein. F5 cells will kill LDb target cells presenting specific antigen (peptide NP68: ASNENMDAM) after “browsing” their surfaces for between 8 min and many hours. Cell death is characterized by abrupt cellular rounding followed by zeiosis (vigorous “boiling” of the cytoplasm and blebbing of the plasma membrane) for 10–20 min, with subsequent cessation of all activity. Departure of cytotoxic T lymphocytes from unkilled target cells is rare, whereas serial killing is sometimes observed. In the absence of antigenic peptide, cytotoxic T lymphocytes browse target cells for much shorter periods, and readily leave to encounter other targets, while never causing target cell death. Two variant antigenic peptides, differing in nonamer position 7 or 8, also act as antigens, albeit with lower efficiency. A third variant peptide NP34 (ASNENMETM), which differs from NP68 in both positions and yet still binds Db, does not stimulate F5 cytotoxicity. Nevertheless, timelapse video analysis shows that NP34 leads to a significant modification of cell behavior, by up-regulating F5–LDb adhesive interactions. These data extend recent studies showing that partial agonists may elicit a subset of the T cell responses associated with full antigen stimulation, by demonstrating that TCR interaction with variant peptide antigens can trigger target cell adhesion and surface exploration without activating the signaling pathway that results in cytotoxicity. PMID:9861010

  20. The Cell Wall and Membrane of Cryptococcus neoformans Possess a Mitogen for Human T Lymphocytes

    PubMed Central

    Mody, Christopher H.; Wood, Cynthia J.; Syme, Rachel M.; Spurrell, Jason C. L.

    1999-01-01

    The mechanism of human T-lymphocyte activation by the pathogenic yeast Cryptococcus neoformans has not been established. Previous investigations have suggested that C. neoformans contains a mitogen for T lymphocytes, while other investigators have attributed lymphocyte proliferation in vitro to a recall antigen. Because of the potential importance of the mechanism of T-cell activation for our understanding of the immune response to C. neoformans, the present studies were performed to determine whether C. neoformans contains a mitogen for T lymphocytes. C. neoformans stimulates fetal blood lymphocytes to proliferate and stimulates proliferation of CD45RA+ cells from adults, indicating that it stimulates naive T cells. The T-cell response to C. neoformans was dependent upon the presence of accessory cells. However, allogeneic cells were sufficient for accessory cell function, indicating that the response was not major histocompatibility complex restricted. The percentage of T cells in the cell cycle was higher than that with the recall antigen tetanus toxoid but lower than that with the mitogenic lectin phytohemagglutinin A or the superantigen Staphylococcus enterotoxin B. Precursor frequency analysis established that 1 in 7,750 ± 2,270 T cells proliferated in response to the cryptococcal cell wall and membrane. Compared to the case for most mitogens or superantigens, the proliferative response is late and the number of T cells that enter the cell cycle and the precursor frequency are low, indicating that the mitogenic effect is modest. However, the mitogenic effect of C. neoformans should be considered when interpreting the immune response to C. neoformans, since even weak mitogens can have profound effects on host defense. PMID:9916111

  1. Difficulties in precise quantitation of CD4+ T lymphocytes for clinical trials: a review.

    PubMed

    Fei, D T; Paxton, H; Chen, A B

    1993-09-01

    Maintenance of CD4+ T helper lymphocyte counts has been used as a surrogate marker of efficacy for drugs in the treatment of AIDS. In a multicenter clinical trial, subtle improvement of CD4+ T cell counts may be masked and misinterpreted if care is not paid to likely sources that can contribute to the variability of measurement of CD4+ T lymphocytes. This review addresses major areas that can contribute to the variability of measurement of CD4+ T lymphocytes, with emphasis on applications to multicenter clinical trials, and proposes areas of improvement that may not be well recognized by the medical community. Whereas there are excellent guidelines for immunophenotyping, equal attention is needed in hematologic enumeration of WBC and absolute lymphocytes. In particular, allowing the margin of error acceptable to blood cell standards for HIV-infected specimens is unsatisfactory. Special attention should also be given to the stability of lymphocytes in the anticoagulant during storage, the lysing method, the quality assurance programs as well as intrasubject fluctuations which may be derived from exercise, medications and diurnal variations. Awareness of these contributing factors by physicians and technical analysts will expedite the discovery of potential therapy in the treatment of AIDS. For a multicenter clinical trial, it is advisable to select a centralized laboratory adopting a uniform protocol with regard to sample preparation and handling, using more stringent quality controls for hematologic analysers, calibration of instruments and immunophenotyping. Pending a true reference standard that can monitor the variation of the entire analytical procedure, we anticipate that future interlaboratory quality assurance programs will include absolute T lymphocyte count, an important parameter for assessing the accuracy and consistency of CD4+ T helper cell counts generated from a laboratory.

  2. Secretion of an articular cartilage proteoglycan-degrading enzyme activity by murine T lymphocytes in vitro.

    PubMed Central

    Kammer, G M; Sapolsky, A I; Malemud, C J

    1985-01-01

    Destruction of articular cartilage is the hallmark of inflammatory arthritides. Enzymes elaborated by mononuclear cells infiltrating the synovium mediate, in part, the degradation of the cartilage extracellular matrix. Since mononuclear cells are the dominant cell type found in chronic inflammatory synovitis, we investigated whether interaction of immune mononuclear cells with antigen initiated the synthesis and secretion of a proteoglycan-degrading enzyme activity. Proteoglycan-degrading enzyme activity was monitored by the capacity of murine spleen cell conditioned medium to release [3H]serine/35SO4 incorporated into rabbit cartilage proteoglycan monomer fraction (A1D1), and by the relative change in specific viscosity of bovine nasal cartilage proteoglycan monomer. The results demonstrated that both virgin and immune mononuclear cells spontaneously generated proteoglycan-degrading enzyme activity and that cellular activation and proliferation induced by the antigen keyhole limpet hemocyanin or the mitogen phytohemagglutinin was not required. Kinetic studies demonstrated stable release of the enzyme activity over 72 h. Cell separation studies showed that T lymphocytes, a thymoma line, and macrophages separately produced proteoglycan-degrading enzyme activity. The enzyme activity has been partially characterized and appears to belong to a class of neutral pH metal-dependent proteinases. These observations, the first to demonstrate that T lymphocytes secrete an enzyme capable of degrading cartilage proteoglycan, raise the possibility that this enzyme activity contributes to cartilage extracellular matrix destruction in vivo. Moreover, these data support the conclusion that production of this enzyme by T lymphocytes is independent of an antigen-specific stimulus. PMID:3897284

  3. [Change in acylneuraminic acid content of T-lymphocytes and in plasma in breast cancer].

    PubMed

    Stickl, H; Huber, W; Faillard, H; Becker, A; Holzhauser, R; Graeff, H

    1991-01-04

    Increased sialic acid levels reflecting tumor burden are found on the surface of T-lymphocytes and in the plasma of patients with carcinoma of the mammary gland. The data of the determinations of sialic acid content and distribution on T-cells, using microanalytical methods such as HPLC and a colorimetric test, show that the total sialic acid content is increased by about 60% and that nearly 80-90% of the sialic acids consist of N-acetyl-9-O-acetyl-neuraminic acid, in comparison to the healthy controls (not containing O-acetylated neuraminic acid). Investigations on lymphocytes of malignant melanoma patients show similar changes of sialic acid content and distribution on the cell surface. Increased sialic acid levels are also found in the plasma of patients with cancer but no O-acetylated derivative can be found. Furthermore the examinations show that the separation of the T-lymphocytes from the total lymphocyte fraction is not required. Determination of sialic acids in the total lymphocyte fraction can be a simplification in carrying out further diagnostic investigations. A high level of sialic acids as "antirecognition factor" seems to be not only a marker of tumor cells but also an attribute of T-lymphocytes, involved in the defence against the malignoma (malignant melanoma, breast cancer). Considering the possible contribution of sialic acid to the immunoregulatory protective mechanism during the first stage of pregnancy, sialic acid content and distribution on T-cells of pregnant women are investigated. Both an increase and a change in the distribution of sialic acids can be excluded.

  4. Linking Pig-Tailed Macaque Major Histocompatibility Complex Class I Haplotypes and Cytotoxic T Lymphocyte Escape Mutations in Simian Immunodeficiency Virus Infection

    PubMed Central

    Gooneratne, Shayarana L.; Alinejad-Rokny, Hamid; Ebrahimi, Diako; Bohn, Patrick S.; Wiseman, Roger W.; O'Connor, David H.; Davenport, Miles P.

    2014-01-01

    ABSTRACT The influence of major histocompatibility complex class I (MHC-I) alleles on human immunodeficiency virus (HIV) diversity in humans has been well characterized at the population level. MHC-I alleles likely affect viral diversity in the simian immunodeficiency virus (SIV)-infected pig-tailed macaque (Macaca nemestrina) model, but this is poorly characterized. We studied the evolution of SIV in pig-tailed macaques with a range of MHC-I haplotypes. SIVmac251 genomes were amplified from the plasma of 44 pig-tailed macaques infected with SIVmac251 at 4 to 10 months after infection and characterized by Illumina deep sequencing. MHC-I typing was performed on cellular RNA using Roche/454 pyrosequencing. MHC-I haplotypes and viral sequence polymorphisms at both individual mutations and groups of mutations spanning 10-amino-acid segments were linked using in-house bioinformatics pipelines, since cytotoxic T lymphocyte (CTL) escape can occur at different amino acids within the same epitope in different animals. The approach successfully identified 6 known CTL escape mutations within 3 Mane-A1*084-restricted epitopes. The approach also identified over 70 new SIV polymorphisms linked to a variety of MHC-I haplotypes. Using functional CD8 T cell assays, we confirmed that one of these associations, a Mane-B028 haplotype-linked mutation in Nef, corresponded to a CTL epitope. We also identified mutations associated with the Mane-B017 haplotype that were previously described to be CTL epitopes restricted by Mamu-B*017:01 in rhesus macaques. This detailed study of pig-tailed macaque MHC-I genetics and SIV polymorphisms will enable a refined level of analysis for future vaccine design and strategies for treatment of HIV infection. IMPORTANCE Cytotoxic T lymphocytes select for virus escape mutants of HIV and SIV, and this limits the effectiveness of vaccines and immunotherapies against these viruses. Patterns of immune escape variants are similar in HIV type 1-infected human

  5. Ferromagnetic nickel silicide nanowires for isolating primary CD4+ T lymphocytes

    NASA Astrophysics Data System (ADS)

    Kim, Dong-Joo; Seol, Jin-Kyeong; Lee, Mi-Ri; Hyung, Jung-Hwan; Kim, Gil-Sung; Ohgai, Takeshi; Lee, Sang-Kwon

    2012-04-01

    Direct CD4+ T lymphocytes were separated from whole mouse splenocytes using 1-dimensional ferromagnetic nickel silicide nanowires (NiSi NWs). NiSi NWs were prepared by silver-assisted wet chemical etching of silicon and subsequent deposition and annealing of Ni. This method exhibits a separation efficiency of ˜93.5%, which is comparable to that of the state-of-the-art superparamagnetic bead-based cell capture (˜96.8%). Furthermore, this research shows potential for separation of other lymphocytes, B, natural killer and natural killer T cells, and even rare tumor cells simply by changing the biotin-conjugated antibodies.

  6. Generation of cytotoxic T lymphocytes and cytostatic acting cells in T. annulata-immune cattle.

    PubMed

    Ahmed, J S; Wiegers, P; Ritz, H; Hartwig, H; Schein, E; Schnittger, L

    2000-01-01

    Cattle immunized against Theileria annulata with schizont containing autologous cell lines are immune to challenge with a homologous parasite strain. Two cell types have been detected in the peripheral blood of the immunized animals: cytotoxic T lymphocytes (CTL) and cytostatic acting cells (CAC). Killing the target cells by CTL is infection associated and is MHC class I restricted. Hence, no cytotoxicity was observed against target cells that were treated with the theilericidal drug buparvaquone or autologous Con A-blasts. The growth inhibition of CAC is MHC unrestricted, and not mediated by cytokine interferon gamma (IFN-gamma).

  7. T Lymphocyte Activation Threshold and Membrane Reorganization Perturbations in Unique Culture Model

    NASA Technical Reports Server (NTRS)

    Adams, C. L.; Sams, C. F.

    2000-01-01

    Quantitative activation thresholds and cellular membrane reorganization are mechanisms by which resting T cells modulate their response to activating stimuli. Here we demonstrate perturbations of these cellular processes in a unique culture system that non-invasively inhibits T lymphocyte activation. During clinorotation, the T cell activation threshold is increased 5-fold. This increased threshold involves a mechanism independent of TCR triggering. Recruitment of lipid rafts to the activation site is impaired during clinorotation but does occur with increased stimulation. This study describes a situation in which an individual cell senses a change in its physical environment and alters its cell biological behavior.

  8. Clonal heterogeneity of synovial fluid T lymphocytes from patients with rheumatoid arthritis

    SciTech Connect

    Duby, A.D.; Sinclair, A.K.; Osborne-Lawrence, S.L. ); Zeldes, W.; Kan, Li; Fox, D.A. )

    1989-08-01

    Although substantial evidence suggests that synovial T lymphocytes are critical in the pathogenesis of rheumatoid arthritis (RA), little is known regarding their antigenic specificities, antigen receptor gene rearrangements, and mechanisms of activation. To assess the extend of expansion of specific clones among RA synovial fluid T cells, Southern blot analyses of T-cell receptor (TCR) gene rearrangements were performed on 40 RA synovial fluid T-cell clones, as well as on fresh and polyclonally activated T cells from RA synovial fluid, RA peripheral blood, and normal peripheral blood. Two of the clones had identical TCR rearrangement patterns, but the remainder were unique. The nonclonal RA T-cell samples showed the same pattern of TCR {beta}-chain rearrangement that was observed among normal peripheral blood T cells, indicating no dominant clonal T-cell population in these samples. It was noted that with sufficient exposure of autoradiograms of the Southern blots, discrete TCR gene rearrangements, representing in some cases common D{sub {beta}}J{sub {beta}} (D, diversity; J, joining) rearrangements, were evident in T cells from peripheral blood of normal individuals and patients with RA, as well as T cells from RA synovial fluid. Taken together, the findings indicate that only a minor degree of oligoclonality can be demonstrated among T lymphocytes from RA synovial fluid.

  9. Induction of surface antigen CD69 expression in T-lymphocytes following exposure to actinomycin D.

    PubMed

    Morgan, C D; Greene, J F; Measel, J W

    1999-10-01

    The expression of surface antigen CD69 in immune response cells is typically associated with the early stage(s) of cell activation, with maximal expression levels within 4 h of appropriate antigenic or mitogenic stimulation, and maintenance of these high expression levels for 18-24 h. The expression profiles of CD69 in human peripheral blood mononuclear cells (PBMC) cultured with actinomycin D prior to mitogenic stimulation were evaluated by direct immunofluorescence using flow cytometry. Pretreatment of PBMC suspensions with low, non-toxic levels of actinomycin D stimulated CD3+ T-lymphocytes to express CD69 in a concentration-dependent manner. Furthermore, CD4+ T-lymphocytes were the primary cells responding in this fashion. Secondary mitogenic stimulation following antibiotic treatment potentiated cellular CD69 expression in these assays. CD69 expression was profoundly suppressed with in vitro actinomycin D concentrations >/=1-2 microg/ml, presumably by interference with cellular transcription/translation mechanisms. Parallel thymidine incorporation assays indicated that actinomycin D effectively inhibited thymidine uptake in a concentration-dependent manner, with complete inhibition at >/=0.1 microg/ml. The evaluation of cell cycling dynamics following antibiotic treatment, with and without secondary mitogen stimulation, indicated no substantial changes in DNA synthesis over controls. The diversity of these responses suggests that expression of CD69 may not solely reflect mitogenic activation status but may, under some conditions, result from induced cellular stress.

  10. Tumor vessel-injuring ability improves antitumor effect of cytotoxic T lymphocytes in adoptive immunotherapy

    PubMed Central

    Kanagawa, N; Yanagawa, T; Nakagawa, T; Okada, N; Nakagawa, S

    2013-01-01

    Angiogenesis is required for normal physiologic processes, but it is also involved in tumor growth, progression and metastasis. Here, we report the development of an immune-based antiangiogenic strategy based on the generation of T lymphocytes that possess killing specificity for cells expressing vascular endothelial growth factor receptor 2 (VEGFR2). To target VEGFR2-expressing cells, we engineered cytotoxic T lymphocyte (CTL) expressing chimeric T-cell receptors (cTCR–CTL) comprised of a single-chain variable fragment (scFv) against VEGFR2 linked to an intracellular signaling sequence derived from the CD3ζ chain of the TCR and CD28 by retroviral gene transduction methods. The cTCR–CTL exhibited efficient killing specificity against VEGFR2 and a tumor-targeting function in vitro and in vivo. Reflecting such abilities, we confirmed that the cTCR–CTL strongly inhibited the growth of a variety of syngeneic tumors after adoptive transfer into tumor-bearing mice without consequent damage to normal tissue. In addition, CTL expressing both cTCR and tumor-specific TCR induced complete tumor regression due to enhanced tumor infiltration by the CTL and long-term antigen-specific function. These findings provide evidence that the tumor vessel-injuring ability improved the antitumor effect of CTLs in adoptive immunotherapy for a broad range of cancers by inducing immune-mediated destruction of the tumor neovasculature. PMID:23175243

  11. CD160 expression defines a uniquely exhausted subset of T lymphocytes in HTLV-1 infection.

    PubMed

    Chibueze, Chioma Ezinne; Yoshimitsu, Makoto; Arima, Naomichi

    2014-10-24

    HTLV-1 infection is a life-long retroviral infection. Chronic viral antigenic stimulation induces persistent infection which results in a clinically asymptomatic carrier state. Only a minor proportion of infected individuals develop adult T cell leukemia/lymphoma (ATLL) or HTLV-1-associated myelopathy/tropical spastic myelopathy (HAM/TSP). This is dependent on a balance of host and genetic factors. CD8+ cytotoxic T lymphocyte function is important in the immune response against viral infection; however, the contribution of CD160 receptor associated with CD8+ T lymphocytes is unclear. Thus, we sought to decipher its role on CTL function in HTLV-1 infection. Here, we report high frequencies of CD160 on CD8+ T cells, with significantly higher levels on HTLV-1 specific CD8+ T cells. Intercepting the CD160 pathway via blockade of the receptor or its ligand, herpes virus entry mediator (HVEM) resulted in improved perforin production and CD107a degranulation of HTLV-1 specific CD8+ T cells. Analysis of the CD160-expressing CD8+ cells demonstrated a unique subset associated with a highly differentiated effector memory based on CD45RA and CCR7 co-expression, increased expression of inhibitory molecules, 2B4 and PD1. Altogether, these results suggest a role for CD160/HVEM pathway in regulating immune response against HTLV-1 infection which may prove promising in the development of immune therapies for the treatment of HTLV-1 infection and other associated disorders.

  12. Disruption of Kv1.3 Channel Forward Vesicular Trafficking by Hypoxia in Human T Lymphocytes*

    PubMed Central

    Chimote, Ameet A.; Kuras, Zerrin; Conforti, Laura

    2012-01-01

    Hypoxia in solid tumors contributes to decreased immunosurveillance via down-regulation of Kv1.3 channels in T lymphocytes and associated T cell function inhibition. However, the mechanisms responsible for Kv1.3 down-regulation are not understood. We hypothesized that chronic hypoxia reduces Kv1.3 surface expression via alterations in membrane trafficking. Chronic hypoxia decreased Kv1.3 surface expression and current density in Jurkat T cells. Inhibition of either protein synthesis or degradation and endocytosis did not prevent this effect. Instead, blockade of clathrin-coated vesicle formation and forward trafficking prevented the Kv1.3 surface expression decrease in hypoxia. Confocal microscopy revealed an increased retention of Kv1.3 in the trans-Golgi during hypoxia. Expression of adaptor protein-1 (AP1), responsible for clathrin-coated vesicle formation at the trans-Golgi, was selectively down-regulated by hypoxia. Furthermore, AP1 down-regulation increased Kv1.3 retention in the trans-Golgi and reduced Kv1.3 currents. Our results indicate that hypoxia disrupts AP1/clathrin-mediated forward trafficking of Kv1.3 from the trans-Golgi to the plasma membrane thus contributing to decreased Kv1.3 surface expression in T lymphocytes. PMID:22134923

  13. Nickel and vanadium metal ions induce apoptosis of T-lymphocyte Jurkat cells.

    PubMed

    Au, Angela; Ha, Jinny; Hernandez, Mauro; Polotsky, Anna; Hungerford, David S; Frondoza, Carmelita G

    2006-12-01

    Metal alloys are used as prosthetic components in the orthopaedic and dental field. However, there is growing concern over the reported leaching of metal ions from implants. Ions released from metals have been thought to be associated with local immune dysfunction, inflammation, and tissue cell death. The objective of our study was to investigate whether nickel(II) and vanadium(V), present at a smaller percentage in most alloys, are cytotoxic to T-lymphocyte cell models. Jurkat T cells possess characteristics similar to human T-lymphocytes and proliferate at a faster rate. Jurkat T cells were incubated with control media alone or with concentrations of 1, 10, and 100 microg/mL of Ni(II) or V(V) for 24 h. Both types of metal ions reduced cell viability and proliferation in a dose-dependent manner. Ni(II) at 10 microg/mL and V(V) at 100 microg/mL activated Caspase-3 expression. Hoechst 33258 staining and transmission electron microscopy revealed chromatin condensation, as well as nuclear blebbing and fragmentation. Induction of DNA fragmentation by Ni(II) at 100 microg/mL was also indicated by agarose electrophoresis. Our observations indicate that Ni and V ions kill T cells via apoptotic and nonapoptotic pathways.

  14. Dissecting eukaryotic cells by coherent phase microscopy: quantitative analysis of quiescent and activated T lymphocytes

    NASA Astrophysics Data System (ADS)

    Tychinsky, Vladimir P.; Kretushev, Alexander V.; Vyshenskaya, Tatiana V.; Shtil, Alexander A.

    2012-07-01

    We present a concept for quantitative characterization of a functional state of an individual eukaryotic cell based on interference imaging. The informative parameters of the phase images of quiescent and mitogen-activated T lymphocytes included the phase thickness, phase volume, the area, and the size of organelles. These parameters were obtained without a special hypothesis about cell structure. Combinations of these parameters generated a ``phase portrait'' of the cell. A simplified spherical multilayer optic model of a T lymphocyte was used to calculate the refractivity profile, to identify structural elements of the image with the organelles, and to interpret the parameters of the phase portrait. The values of phase image parameters underwent characteristic changes in the course of mitogenic stimulation of T cells; thereby, the functional state of individual cells can be described using these parameters. Because the values of the components of the phase portrait are measured in absolute units, it is possible to compare the parameters of images obtained with different interference microscopes. Thus, the analysis of phase portraits provides a new and perspective approach for quantitative, real-time analysis of subcellular structure and physiologic state of an individual cell.

  15. A novel regulatory mechanism of naringenin through inhibition of T lymphocyte function in contact hypersensitivity suppression

    SciTech Connect

    Fang, Feng; Tang, Yijun; Gao, Zhe; Xu, Qiang

    2010-06-25

    Naringenin, a flavonoid in grapefruits and citrus fruits, has been reported to exhibit anti-inflammatory and anti-oxidative activities. Contact hypersensitivity (CHS) is a T cell-mediated immune reaction, and the factors released from macrophages also contribute to this response. Previous studies showed that naringenin suppressed CHS by inhibiting activation and migration of macrophages. However, little is known about naringenin's effects on T lymphocytes. Our study indicated that naringenin potently suppressed picryl chloride (PCl)-induced contact hypersensitivity by inhibiting the proliferation and activation of T lymphocytes. In vitro, both of the activated hapten-specific T cells and the T cells stimulated with anti-CD3/anti-CD28 showed growth arrest after naringenin treatment. Furthermore, naringenin reduced CD69 (the protein level) and cytokines such as IL-2, TNF-{alpha}, and IFN-{gamma} (the mRNA level) expressions which highly expressed by activated T cells. Meanwhile, naringenin also induced T cell apoptosis by upregulation of Bax, Bad, PARP, cleaved-caspase 3 and downregulation of phosphorylated Akt, Bcl-2. These findings suggest that, besides its anti-inflammatory activities in macrophages, naringenin also showed inhibitory effects on the activation and proliferation of T cells to alleviate symptoms of contact hypersensitivity.

  16. Development of T Lymphocytes in the Nasal-associated Lymphoid Tissue (NALT) from Growing Wistar Rats

    PubMed Central

    Sosa, Gustavo A.

    2004-01-01

    The aim of the present report was to study the development of several T-lymphocyte subsets in the nasal-associated lymphoid tissue (NALT) of growing Wistar rats. CD5+ and CD4+ lymphocytes gradually increased with age. A predominance of CD8α+ over CD4+ T cells was found from 7 to 45 days but from 45 to 60 days of age T helper cells outnumbered the cytotoxic subpopulation. The majority of CD8+ T lymphocytes expressed the heterodimeric isoform. The most relevant findings by immunohistochemistry are: (1) the predominance of TCRγδ+ and CD8α+ cells at 7 days postpartum over all the other T-cell subpopulations; and (2) that TCRγβ+ outnumbered TCRαβ+ T cells from 7 to 45 days postpartum whereas αβ T cells predominated in 45- and 60-day-old rats. Besides, cytometric studies have shown that the percentages of TCRγ+, CD8+, as well as the population coexpressing both phenotypes (TCRγδ+CD8α+), were significantly higher in rats at 7 days postpartum when compared to 60 day-old rats. In the present study, the finding of a high number of γδ+ and CD8+ T cells early in NALT development may indicate the importance of these subpopulations in the protection of the nasal mucosa in suckling and weaning Wistar rats. PMID:15154609

  17. Physical association and functional interaction between beta1 integrin and CD98 on human T lymphocytes

    NASA Technical Reports Server (NTRS)

    Miyamoto, Yuko J.; Mitchell, Jason S.; McIntyre, Bradley W.

    2003-01-01

    CD98 is a cell surface protein previously characterized as a cell activation marker, an amino acid transporter, and has recently been implicated in integrin-related functions. Integrins are cell surface proteins, important for homotypic cell aggregation, cell adhesion, and coactivation of T lymphocytes. We have previously shown that the anti-CD98 mAb 80A10, when coimmobilized with anti-CD3 mAb OKT3, is able to mediate human T cell coactivation that is inhibited by anti-beta1 integrin specific mAb 18D3. These results indicated a functional association of CD98 and beta1 integrin signaling but left open the question of a physical association. We now show the induction of homotypic aggregation through CD98 among human T cells and this aggregation was inhibited by anti-beta1 integrin mAb. Therefore, CD98-dependent lymphocyte proliferation and adhesion may involve integrins. Competitive binding assays and fluorescence colocalization analysis suggested that CD98 and beta1 integrin were physically associated. Differential extraction techniques and immunoprecipitations provided the first evidence that the alpha4beta1 integrin and CD98 are specifically associated on human T lymphocytes.

  18. Random migration contributes to cytotoxicity of activated CD8+ T-lymphocytes but not NK cells.

    PubMed

    Onishi, Hideya; Kiyota, Akifumi; Koya, Norihiro; Tanaka, Hiroto; Umebayashi, Masayo; Katano, Mitsuo; Morisaki, Takashi

    2014-08-01

    Activated lymphocytes have the ability to undergo non-directional cell movement known as random migration, although the biological role for this remains unclear. Herein, we investigated how random migration affects cytotoxicity of activated lymphocytes using time-lapse imaging analysis. The kinetics of random migration paralleled cytotoxicity in activated lymphocytes. Sphingosine-1-phosphate (S1P) and its receptor-1 (S1PR1) play an important role in lymphocyte migration. Phosphorylated FTY720 (FTYP), a structural analog of S1P, significantly inhibited random migration and cytotoxicity of activated CD3(+)NKG2D(+)CD8(+) T-lymphocytes but not CD3(-)NKG2D(+)CD56(+) natural killer (NK) cells. In a mouse xenograft model, FTYP-treated activated lymphocytes exhibited lower cytotoxicity and less tumor infiltration for activated CD3(+)NKG2D(+) T-lymphocytes but not CD3(-)NKG2D(+) NK cells. These results suggest that random migration contributes to the cytotoxicity of activated CD8(+) T-cells but not of NK cells.

  19. Human gamma interferon increases the binding of T lymphocytes to endothelial cells.

    PubMed Central

    Yu, C L; Haskard, D O; Cavender, D; Johnson, A R; Ziff, M

    1985-01-01

    Binding of lymphocytes to human umbilical vein endothelial cells (EC) was quantitated by measuring adhesion of 51Cr labelled lymphocytes to endothelial cell monolayers and rosette formation between lymphocytes and EC in suspension. Mitogen stimulated human peripheral blood mononuclear cell culture supernatants and mixed lymphocyte reaction supernatants enhanced the binding of T lymphocytes to EC monolayers or suspensions preincubated with such supernatants. The active component of these supernatants appeared to be gamma interferon (IFN-gamma) since culture supernatants lost activity after heating at 56 degrees C for 60 min, exposure to pH 2.0 or treatment with anti-IFN-gamma. In addition, purified IFN-gamma increased the binding of T lymphocytes to EC (T-EC). This occurred in a concentration dependent manner when IFN-gamma was preincubated with EC but not with lymphocytes. While the optimum concentration of IFN-gamma was 250 u/ml, a significant enhancement was seen with as little as 10 u/ml. These findings suggest that IFN-gamma may play a part in the emigration of lymphocytes to perivascular chronic inflammatory sites by augmenting the adhesion of lymphocytes to the endothelium of small blood vessels. PMID:2935340

  20. Proteomic and protein interaction network analysis of human T lymphocytes during cell-cycle entry

    PubMed Central

    Orr, Stephen J; Boutz, Daniel R; Wang, Rong; Chronis, Constantinos; Lea, Nicholas C; Thayaparan, Thivyan; Hamilton, Emma; Milewicz, Hanna; Blanc, Eric; Mufti, Ghulam J; Marcotte, Edward M; Thomas, N Shaun B

    2012-01-01

    Regulating the transition of cells such as T lymphocytes from quiescence (G0) into an activated, proliferating state involves initiation of cellular programs resulting in entry into the cell cycle (proliferation), the growth cycle (blastogenesis, cell size) and effector (functional) activation. We show the first proteomic analysis of protein interaction networks activated during entry into the first cell cycle from G0. We also provide proof of principle that blastogenesis and proliferation programs are separable in primary human T cells. We employed a proteomic profiling method to identify large-scale changes in chromatin/nuclear matrix-bound and unbound proteins in human T lymphocytes during the transition from G0 into the first cell cycle and mapped them to form functionally annotated, dynamic protein interaction networks. Inhibiting the induction of two proteins involved in two of the most significantly upregulated cellular processes, ribosome biogenesis (eIF6) and hnRNA splicing (SF3B2/SF3B4), showed, respectively, that human T cells can enter the cell cycle without growing in size, or increase in size without entering the cell cycle. PMID:22415777

  1. Apparent cytosolic calcium gradients in T-lymphocytes due to fura-2 accumulation in mitochondria.

    PubMed

    Quintana, Ariel; Hoth, Markus

    2004-08-01

    Fura-2 is the most common dye to measure cytosolic Ca2+ concentrations ([Ca2+]i). To facilitate simultaneous imaging of many cells while preserving their cytosolic environment, fura-2 is often loaded into the cytosol in its membrane-permeant ester form. It has been reported that small amounts of fura-2 accumulate in intracellular compartments, an effect that is usually neglected. We show that either focal or non-focal stimulation methods induce large [Ca2+]i gradients in T-lymphocytes during both, Ca2+ release and Ca2+ influx across the plasma membrane. Interfering with mitochondrial Ca2+ homeostasis and by labeling mitochondria with MitoTracker, we demonstrate that [Ca2+]i gradients co-localize with mitochondria and are attributable to mitochondrial fura-2 sequestration. Gradients could not be avoided by different loading protocols, compromising measurements of "real" [Ca2+]i gradients following T-cell stimulation. They were observed in human blood and lamina propria lymphocytes, Jurkat T-cells, mast cells, but not to the same extent in HEK-293 cells. Finally, we show that T-lymphocytes can be efficiently loaded with the membrane-impermeant fura-2 salt by electroporation and by osmotic lysis of pinocytic vesicles, which result in the loss of [Ca2+]i gradients. These methods are therefore suitable to study localized Ca2+ signals in large populations of T-cells while preserving their cytosolic integrity.

  2. CD31 exhibits multiple roles in regulating T lymphocyte trafficking in vivo.

    PubMed

    Ma, Liang; Cheung, Kenneth C P; Kishore, Madhav; Nourshargh, Sussan; Mauro, Claudio; Marelli-Berg, Federica M

    2012-10-15

    The role of CD31, an Ig-like molecule expressed by leukocytes and endothelial cells (ECs), in the regulation of T lymphocyte trafficking remains contentious. Using CD31-deficient mice, we show that CD31 regulates both constitutive and inflammation-induced T cell migration in vivo. Specifically, T cell:EC interactions mediated by CD31 molecules are required for efficient localization of naive T lymphocytes to secondary lymphoid tissue and constitutive recirculation of primed T cells to nonlymphoid tissues. In inflammatory conditions, T cell:EC CD31-mediated interactions facilitate T cell recruitment to Ag-rich sites. However, endothelial CD31 also provides a gate-keeping mechanism to limit the rate of Ag-driven T cell extravasation. This event contributes to the formation of Ag-specific effector T cell infiltrates and is induced by recognition of Ag on the endothelium. In this context, CD31 engagement is required for restoring endothelial continuity, which is temporarily lost upon MHC molecule ligation by migrating cognate T cells. We propose that integrated adhesive and signaling functions of CD31 molecules exert a complex regulation of T cell trafficking, a process that is differentially adapted depending on cell-specific expression, the presence of inflammatory conditions and the molecular mechanism facilitating T cell extravasation.

  3. Analysis of the mechanisms of human cytotoxic T lymphocyte response inhibition by NO.

    PubMed

    Blesson, Séverine; Thiery, Jérôme; Gaudin, Catherine; Stancou, Rodica; Kolb, Jean-Pierre; Moreau, Jean-Louis; Theze, Jacques; Mami-Chouaib, Fathia; Chouaib, Salem

    2002-10-01

    NO is a potent cellular mediator which has been shown to modulate several immune mechanisms. Using human T lymphocytes as responder cells in a primary mixed lymphocyte reaction, we demonstrated that, at the initiation of the culture, exogenously provided NO via sodium nitroprusside, in non-toxic concentrations, inhibited both allogeneic proliferative and primary cytotoxic responses in a dose-dependent manner. In contrast, it had no effect on the cytotoxic activity of established human TCR (alpha)beta and TCR (gamma)delta cytotoxic T lymphocyte (CTL) clones. The NO inhibitory effect on primary cytotoxic T cell response correlates with inhibition of T cell blastogenesis. Furthermore, under our stimulation conditions, NO induced an inhibition of IL-2 production, an alteration of IL-2R(alpha) expression, and a down-regulation of NF-AT translocation in CD4(+) and CD8(+)allostimulated T cells. Furthermore, we demonstrate that the inhibition of allospecific CTL activity by the NO donor was at least in part related to an inhibition of granzyme B and Fas ligand transcription as revealed respectively by RNase protection and RT-PCR analysis. These results suggest that NO may function to fine tune human CD3(+) T cell activation and subsequent CTL generation.

  4. Evidence of alloreactive T lymphocytes in fetal liver: implications for fetal hematopoietic stem cell transplantation.

    PubMed

    Renda, M C; Fecarotta, E; Dieli, F; Markling, L; Westgren, M; Damiani, G; Jakil, C; Picciotto, F; Maggio, A

    2000-01-01

    The use of hematopoietic stem cells for in utero transplantation to create permanent hematochimerism represents a new concept in fetal therapy, although this approach has provided heterogeneous results. In this paper we have undertaken molecular, phenotypic and functional studies aimed at identifying the presence of fully competent T lymphocytes in samples of fetal livers and cord blood. We found mature VDJ TCR beta chain transcripts in fetal liver cells taken from 7 to 16 weeks of gestation and a similar pattern was detected in cord blood cells sampled from 13.5 to 20.5 weeks of gestation. A Vbeta8 gene sequence comparable to that detected in adult PBMC was found in fetal liver samples at 9 or 17 weeks gestation. PreTalpha message was detected in all samples and its expression decreased in fetal blood samples with increasing gestational age while Calpha message appeared at 9.4 weeks and its expression increased during gestational age. T cell clones obtained from fetal liver cells showed a mature TCR alphabeta+, CD8+ phenotype and displayed strong alloreactivity against allo-MHC class I molecules. The presence of alloreactive T lymphocytes may explain the failure to engraft in fetuses older than 13 to 16 weeks and may provide insights into fetal liver transplantation. Bone Marrow Transplantation (2000) 25, 135-141.

  5. Weft, warp, and weave: the intricate tapestry of calcium channels regulating T lymphocyte function.

    PubMed

    Omilusik, Kyla D; Nohara, Lilian L; Stanwood, Shawna; Jefferies, Wilfred A

    2013-01-01

    Calcium (Ca(2+)) is a universal second messenger important for T lymphocyte homeostasis, activation, proliferation, differentiation, and apoptosis. The events surrounding Ca(2+) mobilization in lymphocytes are tightly regulated and involve the coordination of diverse ion channels, membrane receptors, and signaling molecules. A mechanism termed store-operated Ca(2+) entry (SOCE), causes depletion of endoplasmic reticulum (ER) Ca(2+) stores following T cell receptor (TCR) engagement and triggers a sustained influx of extracellular Ca(2+) through Ca(2+) release-activated Ca(2+) (CRAC) channels in the plasma membrane. The ER Ca(2+) sensing molecule, stromal interaction molecule 1 (STIM1), and a pore-forming plasma membrane protein, ORAI1, have been identified as important mediators of SOCE. Here, we review the role of several additional families of Ca(2+) channels expressed on the plasma membrane of T cells that likely contribute to Ca(2+) influx following TCR engagement, particularly highlighting an important role for voltage-dependent Ca(2+) channels (CaV) in T lymphocyte biology.

  6. A high-content analysis toolbox permits dissection of diverse signaling pathways for T lymphocyte polarization.

    PubMed

    Freeley, Michael; Bakos, Gabor; Davies, Anthony; Kelleher, Dermot; Long, Aideen; Dunican, Dara J

    2010-06-01

    RNA interfering (RNAi) screening strategies offer the potential to elucidate the signaling pathways that regulate integrin and adhesion receptor-mediated changes in T lymphocyte morphology. Of crucial importance, however, is the definition of key sets of parameters that will provide accurate, quantitative, and nonredundant information to flag relevant hits in such assays. In this study, the authors have used an image-based high-content analysis (HCA) technology platform and a panel of 24 pharmacological inhibitors, at a range of concentrations, to define key sets of parameters that enables sensitive and quantitative effects on integrin (LFA-1)-mediated lymphocyte morphology to be evaluated. In particular, multiparametric analysis of lymphocyte morphology that was based on intracellular staining of both the F-actin and alpha-tubulin cytoskeleton resulted in improved ability to discriminate morphological behavior compared to F-actin staining alone. Morphological and fluorescence intensity/distribution profiling of pharmacologically treated lymphocytes stimulated with integrin (LFA-1) and adhesion receptors (CD44) also revealed notable differences in their sensitivity to inhibitors. The assay described here may be used in HCA strategies such as RNAi screening assays to elucidate the signaling pathways and molecules that regulate integrin/adhesion receptor-mediated T lymphocyte polarization.

  7. Role of vitamin D in cytotoxic T lymphocyte immunity to pathogens and cancer.

    PubMed

    Sarkar, Surojit; Hewison, Martin; Studzinski, George P; Li, Yan Chun; Kalia, Vandana

    2016-01-01

    The discovery of vitamin D receptor (VDR) expression in immune cells has opened up a new area of research into immunoregulation by vitamin D, a niche that is distinct from its classical role in skeletal health. Today, about three decades since this discovery, numerous cellular and molecular targets of vitamin D in the immune system have been delineated. Moreover, strong clinical associations between vitamin D status and the incidence/severity of many immune-regulated disorders (e.g. infectious diseases, cancers and autoimmunity) have prompted the idea of using vitamin D supplementation to manipulate disease outcome. While much is known about the effects of vitamin D on innate immune responses and helper T (T(H)) cell immunity, there has been relatively limited progress on the frontier of cytotoxic T lymphocyte (CTL) immunity--an arm of host cellular adaptive immunity that is crucial for the control of such intracellular pathogens as human immunodeficiency virus (HIV), tuberculosis (TB), malaria, and hepatitis C virus (HCV). In this review, we discuss the strong historical and clinical link between vitamin D and infectious diseases that involves cytotoxic T lymphocyte (CTL) immunity, present our current understanding as well as critical knowledge gaps in the realm of vitamin D regulation of host CTL responses, and highlight potential regulatory connections between vitamin D and effector and memory CD8 T cell differentiation events during infections.

  8. Apoptotic CD8 T-lymphocytes disable macrophage-mediated immunity to Trypanosoma cruzi infection

    PubMed Central

    Cabral-Piccin, M P; Guillermo, L V C; Vellozo, N S; Filardy, A A; Pereira-Marques, S T; Rigoni, T S; Pereira-Manfro, W F; DosReis, G A; Lopes, M F

    2016-01-01

    Chagas disease is caused by infection with the protozoan Trypanosoma cruzi. CD8 T-lymphocytes help to control infection, but apoptosis of CD8 T cells disrupts immunity and efferocytosis can enhance parasite infection within macrophages. Here, we investigate how apoptosis of activated CD8 T cells affects M1 and M2 macrophage phenotypes. First, we found that CD8 T-lymphocytes and inflammatory monocytes/macrophages infiltrate peritoneum during acute T. cruzi infection. We show that treatment with anti-Fas ligand (FasL) prevents lymphocyte apoptosis, upregulates type-1 responses to parasite antigens, and reduces infection in macrophages cocultured with activated CD8 T cells. Anti-FasL skews mixed M1/M2 macrophage profiles into polarized M1 phenotype, both in vitro and following injection in infected mice. Moreover, inhibition of T-cell apoptosis induces a broad reprogramming of cytokine responses and improves macrophage-mediated immunity to T. cruzi. The results indicate that disposal of apoptotic CD8 T cells increases M2-macrophage differentiation and contributes to parasite persistence. PMID:27195678

  9. Molecular analyses of in vivo hprt mutations in human T-lymphocytes: IV. Studies in newborns

    SciTech Connect

    McGinniss, M.J.; Nicklas, J.A.; Albertini, R.J. )

    1989-01-01

    In order to characterize in vivo gene mutations that occur during fetal development, molecular analyses were undertaken of mutant 6-thioguanine resistant T-lymphocytes isolated from placental cord blood samples of 13 normal male newborns. These mutant T-cells were studied to define hypoxanthine-guanine phosphoribosyltransferase (hprt) gene structural alterations and to determine T-cell receptor (TCR) gene rearrangement patterns. Structural hprt alterations, as shown by Southern blot analyses, occurred in 85% of these mutant clones. These alterations consisted mostly of deletion of exons 2 and 3. These findings contrast with the 10-20% of gross structural alterations occurring randomly across the entire gene previously reported for T-cell mutants isolated from normal young adults. Iterative analyses of hprt structural alterations and TCR gene rearrangement patterns show that approximately one-third of the newborn derived mutants may have originated as pre- or intrathymic hprt mutations. This too contrasts with previous findings in adults where the background in vivo hprt mutations appeared to originate in postthymic T-lymphocytes.

  10. Pertussis toxin activates adult and neonatal naive human CD4+ T lymphocytes.

    PubMed

    Tonon, Sandrine; Badran, Bassam; Benghiat, Fleur Samantha; Goriely, Stanislas; Flamand, Véronique; Willard-Gallo, Karen; Willems, Fabienne; Goldman, Michel; De Wit, Dominique

    2006-07-01

    Pertussis toxin (PTX) is known to be mitogenic for T lymphocytes, but its direct action on naive human T cells has not been specified. Herein, we show that PTX induces the proliferation of purified adult CD45RA(+)CD4(+) T cells independently of its ADP-ribosyltransferase activity. PTX directly induces TNF-alpha and IL-2 mRNA expression, modulates the level of several cell surface receptors and induces Forkhead box p3 (Foxp3) protein accumulation in naive CD4(+) T cells. Addition of autologous dendritic cells was found to be required for the production of high levels of IFN-gamma by PTX-stimulated naive T cells. These effects of PTX occurred in conjunction with activation of NF-kappaB and NFAT transcription factors. Overall, responses of neonatal CD4(+) T cells to PTX were similar to those of adult CD45RA(+)CD4(+) naive T cells except for their blunted CD40 ligand up-regulation. We suggest that the adjuvant properties of PTX during primary cell-mediated immune responses involve a direct action on naive T lymphocytes in addition to activation of antigen-presenting cells.

  11. CD8+ T lymphocyte expansion, proliferation and activation in dengue fever.

    PubMed

    de Matos, Andréia Manso; Carvalho, Karina Inacio; Rosa, Daniela Santoro; Villas-Boas, Lucy Santos; da Silva, Wanessa Cardoso; Rodrigues, Célia Luiza de Lima; Oliveira, Olímpia Massae Nakasone Peel Furtado; Levi, José Eduardo; Araújo, Evaldo Stanislau Affonso; Pannuti, Claudio Sergio; Luna, Expedito José Albuquerque; Kallas, Esper George

    2015-02-01

    Dengue fever induces a robust immune response, including massive T cell activation. The level of T cell activation may, however, be associated with more severe disease. In this study, we explored the level of CD8+ T lymphocyte activation in the first six days after onset of symptoms during a DENV2 outbreak in early 2010 on the coast of São Paulo State, Brazil. Using flow cytometry we detected a progressive increase in the percentage of CD8+ T cells in 74 dengue fever cases. Peripheral blood mononuclear cells from 30 cases were thawed and evaluated using expanded phenotyping. The expansion of the CD8+ T cells was coupled with increased Ki67 expression. Cell activation was observed later in the course of disease, as determined by the expression of the activation markers CD38 and HLA-DR. This increased CD8+ T lymphocyte activation was observed in all memory subsets, but was more pronounced in the effector memory subset, as defined by higher CD38 expression. Our results show that most CD8+ T cell subsets are expanded during DENV2 infection and that the effector memory subset is the predominantly affected sub population.

  12. Virus-specific T lymphocytes home to the skin during natural dengue infection.

    PubMed

    Rivino, Laura; Kumaran, Emmanuelle A; Thein, Tun-Linn; Too, Chien Tei; Gan, Victor Chih Hao; Hanson, Brendon J; Wilder-Smith, Annelies; Bertoletti, Antonio; Gascoigne, Nicholas R J; Lye, David Chien; Leo, Yee Sin; Akbar, Arne N; Kemeny, David M; MacAry, Paul A

    2015-03-11

    Dengue, which is the most prevalent mosquito-borne viral disease afflicting human populations, causes a spectrum of clinical symptoms that include fever, muscle and joint pain, maculopapular skin rash, and hemorrhagic manifestations. Patients infected with dengue develop a broad antigen-specific T lymphocyte response, but the phenotype and functional properties of these cells are only partially understood. We show that natural infection induces dengue-specific CD8(+) T lymphocytes that are highly activated and proliferating, exhibit antiviral effector functions, and express CXCR3, CCR5, and the skin-homing marker cutaneous lymphocyte-associated antigen (CLA). In the same patients, bystander human cytomegalovirus -specific CD8(+) T cells are also activated during acute dengue infection but do not express the same tissue-homing phenotype. We show that CLA expression by circulating dengue-specific CD4(+) and CD8(+) T cells correlates with their in vivo ability to traffic to the skin during dengue infection. The juxtaposition of dengue-specific T cells with virus-permissive cell types at sites of possible dengue exposure represents a previously uncharacterized form of immune surveillance for this virus. These findings suggest that vaccination strategies may need to induce dengue-specific T cells with similar homing properties to provide durable protection against dengue viruses.

  13. Elevated Expression of Immunoreceptor Tyrosine-Based Inhibitory Motif (TIGIT) on T Lymphocytes is Correlated with Disease Activity in Rheumatoid Arthritis

    PubMed Central

    Luo, Qing; Deng, Zhen; Xu, Chuxin; Zeng, Lulu; Ye, Jianqing; Li, Xue; Guo, Yang; Huang, Zikun; Li, Junming

    2017-01-01

    Background It is well known that lymphocytes play an important role in rheumatoid arthritis (RA). T cell immunoreceptors with immunoglobulin (Ig) and immunoreceptor tyrosine-based inhibitory motif (TIGIT) have immunosuppressive co-stimulatory molecules that mediate inhibitory effects, but their roles in RA are poorly understood. Material/Methods Were recruited 76 patients with RA and 33 healthy controls (HC). Clinical manifestations, laboratory measurements, physical examination, and medical history of RA patients were recorded. The expression of TIGIT on CD3+ T lymphocytes, B lymphocytes, monocytes, neutrophils, CD3+CD4+ T lymphocytes, and CD3+CD8+ T lymphocytes was determined using flow cytometry. The expression of TIGIT on T lymphocytes in patients with RA was further analyzed to investigate its correlations with markers of autoimmune response, inflammation, and disease activity in RA. Results Compared with HC, the expression levels of TIGIT on CD3+CD4+ T lymphocytes and CD3+CD8+ T lymphocytes were significantly increased in patients with RA (P < 0.01). The frequency of TIGIT-expressing CD3+CD4+ T lymphocytes was positively correlated with RF, increased ACPA, ESR, and CRP levels. The frequency of TIGIT-expressing CD3+CD8+ T lymphocytes was positively correlated with RF and ESR levels. Furthermore, the expression level of TIGIT on CD3+CD4+ T lymphocytes was positively correlated with the DAS28 score in RA. Conclusions The expression levels of TIGIT on T lymphocytes were elevated and correlated with disease activity in RA. PMID:28282368

  14. Response of in vivo protein synthesis in T lymphocytes and leucocytes to an endotoxin challenge in healthy volunteers

    PubMed Central

    Januszkiewicz, A; Loré, K; EsséN, P; Andersson, B; Mcnurlan, M A; Garlick, P J; RingdéN, O; Andersson, J; Wernerman, J

    2002-01-01

    In vivo determination of protein synthesis in immune cells reflects metabolic activity and immunological activation. An intravenous injection of endotoxin to healthy volunteers was used as a human sepsis model, and in vivo protein synthesis of T lymphocytes and leucocytes was measured. The results were related to plasma concentrations of selected cytokines, peripheral cell counts and subpopulations of immune cells. The subjects (n = 8 + 8) were randomized to an endotoxin (4 ng/kg) or a saline group. In vivo protein synthesis was determined twice: before and 1–2·5 h after the endotoxin/saline injection. Protein synthesis decreased in isolated T lymphocytes, but increased in leucocytes. Plasma levels of TNF-α, IL-8, IL-6, IL-1 ra and IL-10 were elevated, whereas IL-2 and IFN-γ, produced predominantly by T lymphocytes, did not change in response to endotoxin. Neutrophils increased, whereas lymphocytes and monocytes decreased 2·5 h after the endotoxin injection. Flow cytometry revealed a drop in total CD3+ T lymphocytes and CD56+ natural killer cells, accompanied by an increase in CD15+ granulocytes. In summary, in vivo protein synthesis decreased in T lymphocytes, while the total leucocyte population showed a concomitant increase immediately after the endotoxin challenge. The changes in protein synthesis were accompanied by alterations in immune cell subpopulations and in plasma cytokine levels. PMID:12390314

  15. Response of in vivo protein synthesis in T lymphocytes and leucocytes to an endotoxin challenge in healthy volunteers.

    PubMed

    Januszkiewicz, A; Loré, K; Essén, P; Andersson, B; McNurlan, M A; Garlick, P J; Ringdén, O; Andersson, J; Wernerman, J

    2002-11-01

    In vivo determination of protein synthesis in immune cells reflects metabolic activity and immunological activation. An intravenous injection of endotoxin to healthy volunteers was used as a human sepsis model, and in vivo protein synthesis of T lymphocytes and leucocytes was measured. The results were related to plasma concentrations of selected cytokines, peripheral cell counts and subpopulations of immune cells. The subjects (n = 8 + 8) were randomized to an endotoxin (4 ng/kg) or a saline group. In vivo protein synthesis was determined twice: before and 1-2.5 h after the endotoxin/saline injection. Protein synthesis decreased in isolated T lymphocytes, but increased in leucocytes. Plasma levels of TNF-alpha, IL-8, IL-6, IL-1 ra and IL-10 were elevated, whereas IL-2 and IFN-gamma, produced predominantly by T lymphocytes, did not change in response to endotoxin. Neutrophils increased, whereas lymphocytes and monocytes decreased 2.5 h after the endotoxin injection. Flow cytometry revealed a drop in total CD3+ T lymphocytes and CD56+ natural killer cells, accompanied by an increase in CD15+ granulocytes. In summary, in vivo protein synthesis decreased in T lymphocytes, while the total leucocyte population showed a concomitant increase immediately after the endotoxin challenge. The changes in protein synthesis were accompanied by alterations in immune cell subpopulations and in plasma cytokine levels.

  16. Increased CD45RO expression on T lymphocytes in mediastinal lymph node and pulmonary lesions of patients with pulmonary sarcoidosis.

    PubMed Central

    Fazel, S B; Howie, S E; Krajewski, A S; Lamb, D

    1994-01-01

    Sarcoidosis is characterized by a cell-mediated response mediated by the activation of CD4+ T lymphocytes in an environment lacking adequate numbers of regulatory CD8+ T lymphocytes. Immunohistological studies on frozen tissues have shown that sarcoid lesions have activated CD4 helper/inducer T lymphocytes at the centre of granulomata, whereas lymphocytes at the periphery are mainly CD8 suppressor/cytotoxic cells. In this study we investigated the immunohistological distribution of CD45 isoforms of T cells in 29 paraffin-embedded sarcoid lesions in mediastinal and open lung biopsies. Ten of these were assessed quantitatively, with single-staining of serial sections demonstrating a predominance of CD45RO memory T lymphocytes in granulomata and intergranulomatous areas. Ratios of CD45RO:CD45RA T lymphocytes (or the ratio of memory to naive T cells) were 42.0:1 for granulomata and 17.9:1 for intergranulomatous areas of sarcoid lesions counted. This finding is compatible with the hypothesis that nearly all the lymphocytes present in sarcoid lesions have been previously activated, and selectively home to sarcoid lesions. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:8137547

  17. Human cytotoxic T lymphocytes directed to seasonal influenza A viruses cross-react with the newly emerging H7N9 virus.

    PubMed

    van de Sandt, Carolien E; Kreijtz, Joost H C M; de Mutsert, Gerrie; Geelhoed-Mieras, Martina M; Hillaire, Marine L B; Vogelzang-van Trierum, Stella E; Osterhaus, Albert D M E; Fouchier, Ron A M; Rimmelzwaan, Guus F

    2014-02-01

    In February 2013, zoonotic transmission of a novel influenza A virus of the H7N9 subtype was reported in China. Although at present no sustained human-to-human transmission has been reported, a pandemic outbreak of this H7N9 virus is feared. Since neutralizing antibodies to the hemagglutinin (HA) globular head domain of the virus are virtually absent in the human population, there is interest in identifying other correlates of protection, such as cross-reactive CD8(+) T cells (cytotoxic T lymphocytes [CTLs]) elicited during seasonal influenza A virus infections. These virus-specific CD8(+) T cells are known to recognize conserved internal proteins of influenza A viruses predominantly, but it is unknown to what extent they cross-react with the newly emerging H7N9 virus. Here, we assessed the cross-reactivity of seasonal H3N2 and H1N1 and pandemic H1N1 influenza A virus-specific polyclonal CD8(+) T cells, obtained from HLA-typed study subjects, with the novel H7N9 virus. The cross-reactivity of CD8(+) T cells to H7N9 variants of known influenza A virus epitopes and H7N9 virus-infected cells was determined by their gamma interferon (IFN-γ) response and lytic activity. It was concluded that, apart from recognition of individual H7N9 variant epitopes, CD8(+) T cells to seasonal influenza viruses display considerable cross-reactivity with the novel H7N9 virus. The presence of these cross-reactive CD8(+) T cells may afford some protection against infection with the new virus.

  18. Human Cytotoxic T Lymphocytes Directed to Seasonal Influenza A Viruses Cross-React with the Newly Emerging H7N9 Virus

    PubMed Central

    van de Sandt, Carolien E.; Kreijtz, Joost H. C. M.; de Mutsert, Gerrie; Geelhoed-Mieras, Martina M.; Hillaire, Marine L. B.; Vogelzang-van Trierum, Stella E.; Osterhaus, Albert D. M. E.; Fouchier, Ron A. M.

    2014-01-01

    In February 2013, zoonotic transmission of a novel influenza A virus of the H7N9 subtype was reported in China. Although at present no sustained human-to-human transmission has been reported, a pandemic outbreak of this H7N9 virus is feared. Since neutralizing antibodies to the hemagglutinin (HA) globular head domain of the virus are virtually absent in the human population, there is interest in identifying other correlates of protection, such as cross-reactive CD8+ T cells (cytotoxic T lymphocytes [CTLs]) elicited during seasonal influenza A virus infections. These virus-specific CD8+ T cells are known to recognize conserved internal proteins of influenza A viruses predominantly, but it is unknown to what extent they cross-react with the newly emerging H7N9 virus. Here, we assessed the cross-reactivity of seasonal H3N2 and H1N1 and pandemic H1N1 influenza A virus-specific polyclonal CD8+ T cells, obtained from HLA-typed study subjects, with the novel H7N9 virus. The cross-reactivity of CD8+ T cells to H7N9 variants of known influenza A virus epitopes and H7N9 virus-infected cells was determined by their gamma interferon (IFN-γ) response and lytic activity. It was concluded that, apart from recognition of individual H7N9 variant epitopes, CD8+ T cells to seasonal influenza viruses display considerable cross-reactivity with the novel H7N9 virus. The presence of these cross-reactive CD8+ T cells may afford some protection against infection with the new virus. PMID:24257602

  19. Gibbon ape leukemia virus poorly replicates in primary human T lymphocytes: implications for safety testing of primary human T lymphocytes transduced with GALV-pseudotyped vectors.

    PubMed

    Lamers, Cor H J; Willemsen, Ralph A; van Elzakker, Pascal M M L; Gratama, Jan Willem; Debets, Reno

    2009-04-01

    The Food and Drug Administration/Center for Biologics Evaluation and Research has defined that for retroviral gene therapy, the vector-producing cell, the vector preparation, and the ex vivo gene-transduced cells have to be tested for absence of replication-competent retrovirus (RCR) if the transduced cells are cultured for >4 days. We assessed the sensitivity of the "extended PG4(S+L-) assay" to detect gibbon ape leukemia virus (GALV) RCR, and applied this assay to measure GALV RCR spread in retrovirally transduced T cells. To this end, T cells were expanded for 12 days after transduction with a GALV-envelope pseudotyped retroviral vector expressing single chain variable fragment (anticarbonic anhydrase IX) in presence or absence of GALV RCR. Results showed that: (1) the "extended PG4(S+L-) assay" detects 1 focus-forming unit (ffu) GALV RCR and thus is applicable and sufficiently sensitive to screen human T-cell cultures for absence of infectious GALV RCR; (2) although GALV RCR infect human T cells, it very poorly replicate in T cells; (3) GALV RCR, when present at low levels immediately upon gene transduction (ie, 100 ffu/20x10 T cells in 100 mL), did not spread during a 12-day T-cell culture at clinical scale. Our observation that GALV RCR poorly spreads in primary human T-cell cultures questions the relevance of testing T-cell transductants for RCR on top of testing the vector-producing cells and the clinical vector batch for RCR and warrants evaluation of the current policy for safety testing of ex vivo retrovirally transduced T lymphocytes for GALV RCR.

  20. Dengue virus-infected human dendritic cells reveal hierarchies of naturally expressed novel NS3 CD8 T cell epitopes.

    PubMed

    Piazza, P; Campbell, D; Marques, E; Hildebrand, W H; Buchli, R; Mailliard, R; Rinaldo, C R

    2014-09-01

    Detailed knowledge of dengue virus (DENV) cell-mediated immunity is limited. In this study we characterize CD8(+) T lymphocytes recognizing three novel and two known non-structural protein 3 peptide epitopes in DENV-infected dendritic cells. Three epitopes displayed high conservation (75-100%), compared to the others (0-50%). A hierarchy ranking based on magnitude and polyfunctionality of the antigen-specific response showed that dominant epitopes were both highly conserved and cross-reactive against multiple DENV serotypes. These results are relevant to DENV pathogenesis and vaccine design.

  1. Evidence for the presence of a low molecular-weight activator of suppressor monocytes (LASM) in dialysates of T lymphocytes.

    PubMed

    Nekam, K; Strelkauskas, A J; Fudenberg, H H; Donnan, G G; Goust, J M

    1981-05-01

    Lysates of peripheral blood T lymphocytes from healthy individuals were found to contain a low molecular-weight peptide that inhibited phytohaemagglutinin-induced DNA synthesis in vitro by autologous or allogeneic peripheral blood mononuclear cells. The peptide was dialysable, partially heat stable, resistant to trypsin, RNase, and DNase but not to pronase, and was not part of the membrane receptor involved in rosette formation by T lymphocytes with sheep erythrocytes. It was found to act through monocytes, inducing the synthesis of second mediator responsible for the inhibition of lymphocyte DNA synthesis. This inducer of inhibition, designated as "low molecular-weight activator of suppressor monocytes' (LASM), may have a role in the depression of cellular immune response seen in various pathological conditions involving the destruction of T lymphocytes.

  2. Evidence for the presence of a low molecular-weight activator of suppressor monocytes (LASM) in dialysates of T lymphocytes.

    PubMed Central

    Nekam, K; Strelkauskas, A J; Fudenberg, H H; Donnan, G G; Goust, J M

    1981-01-01

    Lysates of peripheral blood T lymphocytes from healthy individuals were found to contain a low molecular-weight peptide that inhibited phytohaemagglutinin-induced DNA synthesis in vitro by autologous or allogeneic peripheral blood mononuclear cells. The peptide was dialysable, partially heat stable, resistant to trypsin, RNase, and DNase but not to pronase, and was not part of the membrane receptor involved in rosette formation by T lymphocytes with sheep erythrocytes. It was found to act through monocytes, inducing the synthesis of second mediator responsible for the inhibition of lymphocyte DNA synthesis. This inducer of inhibition, designated as "low molecular-weight activator of suppressor monocytes' (LASM), may have a role in the depression of cellular immune response seen in various pathological conditions involving the destruction of T lymphocytes. PMID:6972906

  3. T Lymphocyte Inhibition by Tumor-Infiltrating Dendritic Cells Involves Ectonucleotidase CD39 but Not Arginase-1

    PubMed Central

    Trad, Malika; Gautheron, Alexandrine; Fraszczak, Jennifer; Alizadeh, Darya; Larmonier, Claire; LaCasse, Collin J.; Centuori, Sara; Audia, Sylvain; Samson, Maxime; Ciudad, Marion; Bonnefoy, Francis; Lemaire-Ewing, Stéphanie; Katsanis, Emmanuel; Perruche, Sylvain; Saas, Philippe; Bonnotte, Bernard

    2015-01-01

    T lymphocytes activated by dendritic cells (DC) which present tumor antigens play a key role in the antitumor immune response. However, in patients suffering from active cancer, DC are not efficient at initiating and supporting immune responses as they participate to T lymphocyte inhibition. DC in the tumor environment are functionally defective and exhibit a characteristic of immature phenotype, different to that of DC present in nonpathological conditions. The mechanistic bases underlying DC dysfunction in cancer responsible for the modulation of T-cell responses and tumor immune escape are still being investigated. Using two different mouse tumor models, we showed that tumor-infiltrating DC (TIDC) are constitutively immunosuppressive, exhibit a semimature phenotype, and impair responder T lymphocyte proliferation and activation by a mechanism involving CD39 ectoenzyme. PMID:26491691

  4. Detection of CD4+ and CD8 + T-lymphocytes with the optofluidic ring resonator (OFRR) biosensor

    NASA Astrophysics Data System (ADS)

    Gohring, John T.; Fan, Xudong

    2009-05-01

    We have demonstrated the use of the Opto-Fluidic ring resonator (OFRR) to achieve the label-free detection of CD4+ and CD8+ T-Lymphocytes. The OFRR sensing technology combines microfluidics and optical sensing in a small platform that achieves rapid detection. In this work, white blood cells were obtained from healthy blood and the concentration altered to reflect CD4 and CD8 concentrations of HIV infected individuals. The OFRR was modified to effectively capture these receptors located on T-Lymphocytes and obtain a sensing signal through interaction with an evanescent field. Results show isolation of CD4+ and CD8+ T-Lymphocytes at medically significant levels. This work will lead to a device that can provide a CD4 and CD8 count to measure HIV progression in a low cost sensing setup.

  5. [Peripheral blood T lymphocyte subtypes in multiple sclerosis--dependance of clinical course and duration of the disease].

    PubMed

    Vojinović, S; Vojinović, K; Kamenov, B; Vojinović, D; Gocić-Stanković, D

    1994-01-01

    Multiple sclerosis is a disease mediated by immunological mechanisms, with characteristics of an autoimmune prosses. We registered changes in distribution of immunophenotipisation markers CD2, CD3, CD4, CD8, CD56 and DR, by indirect immunoflourescence assay, on immune cells of peripheral blood. We tested 20 patients with clinically definite category of illness, in exacerbation, and 10 healthy individuals. Multiple sclerosis patients had changes in distribution of T cell subtypes in exacerbation, which correlated with clinical course and duration of the disease. Relapsing-remitting course of disease is followed by decrease of activated T lymphocytes and fluctuation of CD4+ T lymphocytes, while there are no changes in studied markers at patients with progressive course. Duration of the disease over 10 years is followed by decreases of CD4+ and CD8+ T lymphocytes, independent of course of the disease.

  6. Depletion of L-arginine induces autophagy as a cytoprotective response to endoplasmic reticulum stress in human T lymphocytes

    PubMed Central

    García-Navas, Rósula; Munder, Markus; Mollinedo, Faustino

    2012-01-01

    L-arginine (L-Arg) deficiency results in decreased T-cell proliferation and impaired T-cell function. Here we have found that L-Arg depletion inhibited expression of different membrane antigens, including CD247 (CD3ζ), and led to an ER stress response, as well as cell cycle arrest at G0/G1 in both human Jurkat and peripheral blood mitogen-activated T cells, without undergoing apoptosis. By genetic and biochemical approaches, we found that L-Arg depletion also induced autophagy. Deprivation of L-Arg induced EIF2S1 (eIF2α), MAPK8 (JNK), BCL2 (Bcl-2) phosphorylation, and displacement of BECN1 (Beclin 1) binding to BCL2, leading to autophagosome formation. Silencing of ERN1 (IRE1α) prevented the induction of autophagy as well as MAPK8 activation, BCL2 phosphorylation and XBP1 splicing, whereas led T lymphocytes to apoptosis under L-Arg starvation, suggesting that the ERN1-MAPK8 pathway plays a major role in the activation of autophagy following L-Arg depletion. Autophagy was required for survival of T lymphocytes in the absence of L-Arg, and resulted in a reversible process. Replenishment of L-Arg made T lymphocytes to regain the normal cell cycle profile and proliferate, whereas autophagy was inhibited. Inhibition of autophagy by ERN1, BECN1 and ATG7 silencing, or by pharmacological inhibitors, promoted cell death of T lymphocytes incubated in the absence of L-Arg. Our data indicate for the first time that depletion of L-Arg in T lymphocytes leads to a reversible response that preserves T lymphocytes through ER stress and autophagy, while remaining arrested at G0/G1. Our data also show that the L-Arg depletion-induced ER stress response could lead to apoptosis when autophagy is blocked. PMID:22874569

  7. Anticytotoxic T-Lymphocyte Antigen-4 Induced Autoimmune Hypophysitis: A Case Report and Literature Review

    PubMed Central

    Korytkowski, Mary T.

    2015-01-01

    Objective. We describe a case of autoimmune hypophysitis induced by the anticytotoxic T-lymphocyte antigen-4 (CTLA-4) agent, ipilimumab. Methods. Case presentation and review of the literature. Results. Autoimmune hypophysitis, a previously described rare disorder, is being recognized more frequently as a side effect of novel immunomodulatory agents used in the treatment of malignancies such as melanoma. CTLA-4 agents are associated with immune-related adverse effects (irAE) which occur as a result of activation (or lack of inactivation) of the immune response. This impacts not only malignant cells but also different host organ-systems. Autoimmune hypophysitis is one of several endocrinopathies associated with these agents. Conclusion. It is important that endocrinologists become familiar with the endocrinopathies, such as autoimmune hypophysitis, associated with new immunomodulator agents which are being used with increasing frequency to treat a variety of malignancies. PMID:25694832

  8. Peripheral regulatory T lymphocytes recirculating to the thymus suppress the development of their precursors.

    PubMed

    Thiault, Nicolas; Darrigues, Julie; Adoue, Véronique; Gros, Marine; Binet, Bénédicte; Perals, Corine; Leobon, Bertrand; Fazilleau, Nicolas; Joffre, Olivier P; Robey, Ellen A; van Meerwijk, Joost P M; Romagnoli, Paola

    2015-06-01

    Most T lymphocytes, including regulatory T cells (Treg cells), differentiate in the thymus. The age-dependent involution of this organ leads to decreasing production of T cells. Here we found that the output of new Treg cells from the thymus decreased substantially more than that of conventional T cells. Peripheral mouse and human Treg cells recirculated back to the thymus, where they constituted a large proportion of the pool of Treg cells and displayed an activated and differentiated phenotype. In the thymus, the recirculating cells exerted their regulatory function by inhibiting interleukin 2 (IL-2)-dependent de novo differentiation of Treg cells. Thus, Treg cell development is controlled by a negative feedback loop in which mature progeny cells return to the thymus and restrain development of precursors of Treg cells.

  9. Detection of doxorubicin-induced apoptosis of leukemic T-lymphocytes by laser tweezers Raman spectroscopy

    PubMed Central

    Moritz, Tobias J.; Taylor, Douglas S.; Krol, Denise M.; Fritch, John; Chan, James W.

    2010-01-01

    Laser tweezers Raman spectroscopy (LTRS) was used to acquire the Raman spectra of leukemic T lymphocytes exposed to the chemotherapy drug doxorubicin at different time points over 72 hours. Changes observed in the Raman spectra were dependent on drug exposure time and concentration. The sequence of spectral changes includes an intensity increase in lipid Raman peaks, followed by an intensity increase in DNA Raman peaks, and finally changes in DNA and protein (phenylalanine) Raman vibrations. These Raman signatures are consistent with vesicle formation, cell membrane blebbing, chromatin condensation, and the cytoplasm of dead cells during the different stages of drug-induced apoptosis. These results suggest the potential of LTRS as a real-time single cell tool for monitoring apoptosis, evaluating the efficacy of chemotherapeutic treatments, or pharmaceutical testing. PMID:21258536

  10. T lymphocytes hunt for antigen in lymph nodes like Lone Sharks

    NASA Astrophysics Data System (ADS)

    Raychaudhuri, Subhadip; Dustin, Michael L.; Chakraborty, Arup K.

    2004-03-01

    T lymphocytes (T cells) are the orchestrators of the adaptive immune response. T cells sample antigen presenting cells (APCs) in environments such as the lymphoid organs. Recent in vivo and in vitro imaging experiments using two-photon microscopy have demonstrated that, on large length scales, the motion of T cells within lymphoid organs is characterized by random walk statistics. This is surprising because directed chemokine gradients are expected to provide directional cues as T cells hunt for antigen presenting cells. Using stochastic Monte Carlo simulations and mathematical arguments, we show that short range chemokine gradient-directed motion yields random walk statistics on long length scales. We also demonstrate that this strategy for hunting for antigen is superior to others such as completely random or long-range chemokine directed migration strategies. Further insights are provided by analyzing our results using velocity autocorrelation functions.

  11. Emerging technologies for point-of-care CD4 T-lymphocyte counting

    PubMed Central

    Boyle, David S.; Hawkins, Kenneth R.; Steele, Matthew S.; Singhal, Mitra; Cheng, Xuanhong

    2012-01-01

    A CD4 T-lymphocyte count determines eligibility for antiretroviral therapy (ART) with patients recently diagnosed with HIV and also monitors the efficacy of ART treatment thereafter. ART slows the progression of HIV to AIDS. In the developing world, CD4 tests are often performed in centralized laboratories, typically in urban areas. The expansion of ART programs into rural areas has created a need for rapid CD4 counting as logistical barriers can delay the timely dissemination of test results and affect patient care through delay in intervention or loss of follow-up care. CD4 measurement at the point-of-care (POC) in rural areas could help facilitating ART and monitoring of treatment. This review highlights recent technology developments with applications towards determining CD4 counts at the POC. PMID:21798607

  12. CD152 (CTLA-4) regulates effector functions of CD8+ T lymphocytes by repressing Eomesodermin.

    PubMed

    Hegel, Johannes K; Knieke, Karin; Kolar, Paula; Reiner, Steven L; Brunner-Weinzierl, Monika C

    2009-03-01

    CD8(+) T lymphocytes are required for effective host defense against pathogens and also for mediating effector responses against uncontrolled proliferating self-tissues. In this study, we determine that individual CD8(+) T cells are tightly controlled in their effector functions by CD152 (CTLA-4). We demonstrate that signals induced by CD152 reduce the frequency of IFN-gamma and granzyme B expressing CD8(+) T cells independently of the transcription factors T-bet or cKrox by selectively inhibiting accumulation of Eomesodermin mRNA and protein. Ectopic expression of Eomesodermin reversed the CD152-mediated inhibition of effector molecule production. Additionally, enhanced cytotoxicity of individual CD8(+) T cells differentiated in the absence of CD152 signaling was determined in vivo. These novel insights extend our understanding of how immune responses of CD8(+) T cells are selectively modulated.

  13. Alteration of membrane phospholipid methylation by adenosine analogs does not affect T lymphocyte activation

    SciTech Connect

    Gormand, F.; Pacheco, Y. ); Fonlupt, P. ); Revillard, J.P. )

    1990-01-01

    Membrane phospholipid methylation has been described during activation of various immune cells. Moreover recent data indicated modulation of immune cells functions by adenosine. As S-adenosyl-methionine and S-adenosyl-homocysteine are adenosine analogs and modulators of transmethylation reactions, the effects of SAH and SAM were investigated on membrane phospholipid methylation and lymphocyte activation. SAM was shown to induce the membrane phospholipid methylation as assessed by the {sup 3}Hmethyl-incorporation in membrane extract. This effect was inhibited by SAH. In contrast SAM and SAH did not affect the phytohemagglutinin-induced proliferative response of peripheral blood mononuclear cells. SAH neither modified the early internalization of membrane CD3 antigens nor did it prevent the late expression of HLA-DR antigens on lymphocytes activated by phytohemagglutinin. These results indicate that in vitro alteration of phospholipid methylation does not affect subsequent steps of human T lymphocyte activation and proliferation.

  14. Fibroblastic reticular cells: organization and regulation of the T lymphocyte life cycle.

    PubMed

    Brown, Flavian D; Turley, Shannon J

    2015-02-15

    The connective tissue of any organ in the body is generally referred to as stroma. This complex network is commonly composed of leukocytes, extracellular matrix components, mesenchymal cells, and a collection of nerves, blood, and lymphoid vessels. Once viewed primarily as a structural entity, stromal cells of mesenchymal origin are now being intensely examined for their ability to directly regulate various components of immune cell function. There is particular interest in the ability of stromal cells to influence the homeostasis, activation, and proliferation of T lymphocytes. One example of this regulation occurs in the lymph node, where fibroblastic reticular cells support the maintenance of naive T cells, induce Ag-specific tolerance, and restrict the expansion of newly activated T cells. In an effort to highlight the varied immunoregulatory properties of fibroblastic reticular cells, we reviewed the most recent advances in this field and provide some insights into potential future directions.

  15. Aloe QDM complex enhances specific cytotoxic T lymphocyte killing in vivo in metabolic disease mice.

    PubMed

    Lee, Youngjoo; Kim, Jiyeon; An, Jinho; Lee, Heetae; Kong, Hyunseok; Song, Youngcheon; Shin, Eunju; Do, Seon-Gil; Lee, Chong-Kil; Kim, Kyungjae

    2017-03-01

    We developed spontaneous diet-induced metabolic disease in mice by feeding them a high-fat diet for 23 weeks and administered Aloe QDM complex for 16 weeks to examine its restorative effect on immune disorders and metabolic syndrome. A series of immune functional assays indicated Aloe QDM complex enhanced lymphocyte proliferation and antigen-specific immunity as determined by the restored functions of cytotoxic T lymphocytes (CTL) and IgG production. The elevated serum TNF-α level was also regulated by Aloe QDM complex treatment, which suggested its complex therapeutic potential. As for metabolic phenotypes, oral administration of Aloe QDM complex significantly improved diabetic symptoms, including high fasting glucose levels and glucose tolerance, and distinctly alleviated lipid accumulation in adipose and hepatic tissue. The simultaneous restoration of Aloe QDM complex on metabolic syndrome and host immune dysfunction, especially on the specific CTL killing was first elucidated in our study.

  16. Cytotoxic T lymphocytes against disease-associated determinant(s) in ankylosing spondylitis

    PubMed Central

    1986-01-01

    Cytotoxic T lymphocytes, induced by stimulating the PBMC of an HLA-B27+ normal individual (B27+, AS-) with the PBMC of an HLA-identical sibling suffering from ankylosing spondylitis (AS) (B27+, AS+), specifically lyse B27+, AS+ PBMC but not PBMC from HLA-27+ or B27-, AS- normal controls, or from HLA-B27- AS patients (B27-,AS+). CTL of similar specificity can also be raised by immunizing in vitro B27+,AS- cells with autologous cells modified by cross-reactive bacterial antigens. These results suggest that CTL can recognize certain bacterial antigens in association with HLA-B27 and that this interaction may lead to an inflammatory episode during the initial stages of the disease. PMID:3528379

  17. Human IFN-gamma up-regulates IL-2 receptors in mitogen-activated T lymphocytes.

    PubMed Central

    Rodriguez, M A; De Sanctis, J B; Blasini, A M; Leon-Ponte, M; Abadi, I

    1990-01-01

    This study examined the role of human recombinant interferon-gamma (rIFN-gamma) in the expression of interleukin-2 receptors (IL-2R) by human T lymphocytes. rIFN-gamma enhanced total numbers of IL-2R in mitogen-activated but not resting T cells. Scatchard plot analysis indicated that rIFN-gamma increased both high- and low-affinity receptors, with a predominant effect on the latter. Phytohaemagglutinin (PHA)-activated T cells treated with IFN-gamma showed higher IL-2 binding and greater IL-2 internalization and degradation than cells treated with PHA alone. There was a corresponding increase of mitogen-driven proliferative responses, indicating an increase of functional receptors in IFN-treated cultures. IFN-gamma may influence T-cell activation and proliferation by enhancing expression of IL-2R and promoting IL-2 uptake by mitogen-activated lymphocytes. PMID:2110548

  18. Leukotriene B4 mediates γδ T lymphocyte migration in response to diverse stimuli

    PubMed Central

    Costa, Maria Fernanda de Souza; de Souza-Martins, Raquel; de Souza, Mariana C.; Benjamim, Cláudia F.; Piva, Bruno; Diaz, Bruno L.; Peters-Golden, Marc; Henriques, Maria das Graças; Canetti, Cláudio; Penido, Carmen

    2010-01-01

    Herein, we investigated the involvement of the 5-LO-derived lipid mediator LTB4 in γδ T cell migration. When injected into the i.pl. space of C57BL/6 mice, LTB4 triggered γδ T lymphocyte mobilization in vivo, a phenomenon also observed in in vitro chemotaxis assays. The i.pl. injection of Escherichia coli endotoxin (LPS) triggered increased levels of LTB4 in pleural cavities. The in vivo inhibition of LTB4 biosynthesis by the 5-LO inhibitor zileuton or the FLAP inhibitor MK886 attenuated LPS-induced γδ T cell accumulation into pleural cavities. Accordingly, 5-LO KO mice failed to recruit γδ T cells into the inflammatory site after i.pl. LPS. Antagonists of the high-affinity LTB4 receptor BLT1, CP105,696, and LY292476 also attenuated LPS-induced γδ T cell accumulation in pleural cavities as well as in vitro chemotaxis toward pleural washes obtained from LPS-simulated mice. LTB4/BLT1 also accounted for γδ T cell migration induced by i.pl. administration of Mycobacterium bovis BCG or antigen in sensitized mice. BLT1 was expressed on naïve, resident as well as LPS-recruited γδ T cells. Isolated γδ T cells were found to undergo F-actin cytoskeleton reorganization when incubated with LTB4 in vitro, confirming that γδ T lymphocytes can respond directly to LTB4. In addition to its direct effect on γδ T cells, LTB4 triggered their accumulation indirectly, via modulation of CCL2 production in mouse pleural cavities. These data show that γδ T cell migration into the pleural cavity of mice during diverse inflammatory responses is dependent on LTB4/BLT1. PMID:19880577

  19. Modulation of potassium channels in human T lymphocytes: effects of temperature.

    PubMed Central

    Pahapill, P A; Schlichter, L C

    1990-01-01

    1. The predominant channels found in lymphocytes with patch-clamp whole-cell recordings are voltage-gated K+ channels. Several lines of evidence suggest that these channels are involved in lymphocyte function. Most lymphocyte functions are temperature sensitive and have not been correlated with electrophysiology at different temperatures. We have examined the effect of temperature on the voltage-dependent K+ channel in normal human T lymphocytes. Both macroscopic current and single-channel events were studied with whole-cell recordings at temperatures from 5 to 42 degrees C. 2. Peak conductance, activation rate, inactivation rate and rate of recovery from inactivation all increased progressively as the temperature increased. The effect of temperature on channel opening processes was greater at low temperatures. In contrast, the inactivation process was most sensitive to temperature changes above room temperature. Arrhenius plots of conductance and kinetic parameters were curvilinear with no obvious break-points. 3. The increase in whole-cell conductance at 37 degrees C was due to both an increase in the single-channel conductance and in the probability that each channel is open at any time. 4. K+ currents were fitted by Hodgkin-Huxley equations with n4j kinetics providing the best description of the currents at all temperatures tested. 5. Steady-state activation- and inactivation-voltage curves shifted in opposite directions with warming, resulting in a greater area of overlap of the curves ('window' current). The increase in resting K+ channel activity predicted by a greater window current was confirmed with single-channel measurements. 6. The present study has shown that the behaviour of K+ channels in human T lymphocytes is temperature dependent. PMID:2352174

  20. Charybdotoxin blocks voltage-gated K+ channels in human and murine T lymphocytes

    PubMed Central

    1989-01-01

    A variety of scorpion venoms and purified toxins were tested for effects on ion channels in human T lymphocytes, a human T leukemia cell line (Jurkat), and murine thymocytes, using the whole-cell patch-clamp method. Nanomolar concentrations of charbdotoxin (CTX), a purified peptide component of Leiurus quinquestriatus venom known to block Ca2+- activated K+ channels from muscle, blocked "type n" voltage-gated K+ channels in human T lymphoid cells. The Na+ channels occasionally expressed in these cells were unaffected by the toxin. From the time course of development and removal of K+ channel block we determined the rates of CTX binding and unbinding. CTX blocks K+ channels in Jurkat cells with a Kd value between 0.5 and 1.5 nM. Of the three types of voltage-gated K+ channels present in murine thymocytes, types n and n' are blocked by CTX at nanomolar concentrations. The third variety of K+ channels, "type l," is unaffected by CTX. Noxiustoxin (NTX), a purified toxin from Centruroides noxius known to block Ca2+-activated K+ channels, also blocked type n K+ channels with a high degree of potency (Kd = 0.2 nM). In addition, several types of crude scorpion venoms from the genera Androctonus, Buthus, Centruroides, and Pandinus blocked type n channels. We conclude that CTX and NTX are not specific for Ca2+ activated K+ channels and that purified scorpion toxins will provide useful probes of voltage-gated K+ channels in T lymphocytes. The existence of high-affinity sites for scorpion toxin binding may help to classify structurally related K+ channels and provide a useful tool for their biochemical purification. PMID:2475579

  1. T lymphocyte immunophenotypes in the cerebrospinal fluid of dogs with visceral leishmaniasis.

    PubMed

    Grano, Fernanda G; Silva, José Eduardo Dos S; Melo, Guilherme D; Perosso, Juliana; Lima, Valéria M F; Machado, Gisele F

    2016-12-15

    Visceral leishmaniasis (VL) is a disease causing several clinical manifestations in dogs, including neurological disorders. Nevertheless, there are few studies related to the evaluation of the brain alterations during VL. Evidences of the involvement of cerebral barriers in infected dogs was reported, including the presence of brain inflammatory infiltrate, with a predominance of CD3+ T cells. Therefore, the aim of this study was to determine the immunophenotypes of T lymphocytes in the cerebrospinal fluid (CSF), as well as in peripheral blood, and to correlate with brain alterations in dogs with VL. We detected elevated percentages of double negative (DN) and double positive (DP) T cells in the CSF, with a predominance of TCRαb. In the histopathological analysis, we observed a predominance of lymphoplasmacytic infiltrate, mainly in leptomeninges, ranging from mild to intense, and we observed a positive correlation between the intensity of inflammation in the subependymal area and the DN T cells of the CSF. Thus, the DN T cells seem be acting as villains of the immune system through pro-inflammatory mechanisms. Further, the proportion of the different population of CSF T cells did not differ from those observed in the blood, which provides us with more evidence of blood-CSF barrier breakdown. Together, the results provide more explanation to the inflammation observed in the brain of dogs with VL, which the DN T cells contribute to the origin and progression of the neurological disease. This study provides insight into the immunophenotypes of T lymphocytes in the CSF during canine visceral leishmaniasis.

  2. Erythrocyte receptor (CD2)-bearing T lymphocytes are affected by diet in experimental pulmonary tuberculosis.

    PubMed Central

    Bartow, R A; McMurray, D N

    1990-01-01

    Outbred (Hartley) and inbred (strain 2 and 13) guinea pigs were vaccinated with Mycobacterium bovis BCG and placed on isocaloric, purified diets containing either 10 or 30% ovalbumin or on commercial guinea pig chow. Six weeks later, the animals were challenged by the respiratory route with virulent M. tuberculosis H37Rv. At intervals postchallenge, groups were tuberculin tested and sacrificed. Thymus-dependent (T) lymphocytes were enumerated either by rosette formation with rabbit erythrocytes or by the indirect immunofluorescence assay (IFA) with a guinea pig pan-T-cell monoclonal antibody, 8BE6. Protein-deficient guinea pigs of all three strains had significantly fewer erythrocyte rosette-forming (CD2+) T cells in the peripheral blood, and malnourished strain 2 and Hartley guinea pigs exhibited reduced levels of CD2+ T cells in the thymus. In contrast, animals of all three strains fed the low-protein diet harbored more CD2+ T cells in the bronchotracheal lymph nodes than did their control-fed counterparts. A larger proportion of lymphocytes from the blood and lymph nodes of all three strains were IFA positive than formed erythrocyte rosettes regardless of diet treatment. Diet had no effect on IFA-positive lymphocytes in those organs. Protein deficiency is associated with significant alterations in the number and/or distribution of T lymphocytes expressing functional CD2-receptors in BCG-vaccinated animals exposed to virulent mycobacteria by the pulmonary route. These alterations may contribute to the reduction in BCG vaccine efficacy observed in this model. PMID:1971259

  3. Rapid alterations of cell cycle control proteins in human T lymphocytes in microgravity

    PubMed Central

    2012-01-01

    In our study we aimed to identify rapidly reacting gravity-responsive mechanisms in mammalian cells in order to understand if and how altered gravity is translated into a cellular response. In a combination of experiments using "functional weightlessness" provided by 2D-clinostats and real microgravity provided by several parabolic flight campaigns and compared to in-flight-1g-controls, we identified rapid gravity-responsive reactions inside the cell cycle regulatory machinery of human T lymphocytes. In response to 2D clinorotation, we detected an enhanced expression of p21 Waf1/Cip1 protein within minutes, less cdc25C protein expression and enhanced Ser147-phosphorylation of cyclinB1 after CD3/CD28 stimulation. Additionally, during 2D clinorotation, Tyr-15-phosphorylation occurred later and was shorter than in the 1 g controls. In CD3/CD28-stimulated primary human T cells, mRNA expression of the cell cycle arrest protein p21 increased 4.1-fold after 20s real microgravity in primary CD4+ T cells and 2.9-fold in Jurkat T cells, compared to 1 g in-flight controls after CD3/CD28 stimulation. The histone acetyltransferase (HAT) inhibitor curcumin was able to abrogate microgravity-induced p21 mRNA expression, whereas expression was enhanced by a histone deacetylase (HDAC) inhibitor. Therefore, we suppose that cell cycle progression in human T lymphocytes requires Earth gravity and that the disturbed expression of cell cycle regulatory proteins could contribute to the breakdown of the human immune system in space. PMID:22273506

  4. Prediction of cross-recognition of peptide-HLA A2 by Melan-A-specific cytotoxic T lymphocytes using three-dimensional quantitative structure-activity relationships.

    PubMed

    Fagerberg, Theres; Zoete, Vincent; Viatte, Sebastien; Baumgaertner, Petra; Alves, Pedro M; Romero, Pedro; Speiser, Daniel E; Michielin, Olivier

    2013-01-01

    The cross-recognition of peptides by cytotoxic T lymphocytes is a key element in immunology and in particular in peptide based immunotherapy. Here we develop three-dimensional (3D) quantitative structure-activity relationships (QSARs) to predict cross-recognition by Melan-A-specific cytotoxic T lymphocytes of peptides bound to HLA A*0201 (hereafter referred to as HLA A2). First, we predict the structure of a set of self- and pathogen-derived peptides bound to HLA A2 using a previously developed ab initio structure prediction approach [Fagerberg et al., J. Mol. Biol., 521-46 (2006)]. Second, shape and electrostatic energy calculations are performed on a 3D grid to produce similarity matrices which are combined with a genetic neural network method [So et al., J. Med. Chem., 4347-59 (1997)] to generate 3D-QSAR models. The models are extensively validated using several different approaches. During the model generation, the leave-one-out cross-validated correlation coefficient (q (2)) is used as the fitness criterion and all obtained models are evaluated based on their q (2) values. Moreover, the best model obtained for a partitioned data set is evaluated by its correlation coefficient (r = 0.92 for the external test set). The physical relevance of all models is tested using a functional dependence analysis and the robustness of the models obtained for the entire data set is confirmed using y-randomization. Finally, the validated models are tested for their utility in the setting of rational peptide design: their ability to discriminate between peptides that only contain side chain substitutions in a single secondary anchor position is evaluated. In addition, the predicted cross-recognition of the mono-substituted peptides is confirmed experimentally in chromium-release assays. These results underline the utility of 3D-QSARs in peptide mimetic design and suggest that the properties of the unbound epitope are sufficient to capture most of the information to determine the

  5. Can clinical response to cyclosporin in chronic severe asthma be predicted by an in vitro T-lymphocyte proliferation assay?

    PubMed

    Alexander, A G; Barnes, N C; Kay, A B; Corrigan, C J

    1996-07-01

    This study tests the hypothesis that the clinical response to cyclosporin therapy of patients with chronic severe asthma is related to the sensitivity of their T-lymphocytes to the antiproliferative effects of cyclosporin in vitro. In a previous study, we observed such a relationship with glucocorticoids and the same lectin-driven proliferation assay was used in the present study. Peripheral blood mononuclear cells were obtained from 33 patients participating in a cross-over trial of oral cyclosporin therapy during both cyclosporin and placebo treatment periods, and cultured in the presence of phytohaemagglutinin and serial dilutions of cyclosporin and dexamethasone. Proliferation was measured by tritiated thymidine uptake. Both cyclosporin and dexamethasone inhibited T-lymphocyte proliferation in a concentration-dependent manner in vitro at concentrations encompassing those achieved in peripheral blood during therapy in vivo. T-lymphocytes from the asthmatic patients showed a range of sensitivity to the antiproliferative effects of cyclosporin, but this could not be correlated with improvements in peak expiratory flow rate (PEFR) or forced expiratory volume in one second (FEV1) during cyclosporin therapy as compared with placebo. In contrast to previous observations with glucocorticoids, this in vitro T-lymphocyte proliferation assay is not predictive of clinical response to cyclosporin therapy in chronic severe asthmatics.

  6. Recombinant poxvirus boosting of DNA-primed rhesus monkeys augments peak but not memory T lymphocyte responses.

    PubMed

    Santra, Sampa; Barouch, Dan H; Korioth-Schmitz, Birgit; Lord, Carol I; Krivulka, Georgia R; Yu, Faye; Beddall, Margaret H; Gorgone, Darci A; Lifton, Michelle A; Miura, Ayako; Philippon, Valerie; Manson, Kelledy; Markham, Phillip D; Parrish, John; Kuroda, Marcelo J; Schmitz, Jörn E; Gelman, Rebecca S; Shiver, John W; Montefiori, David C; Panicali, Dennis; Letvin, Norman L

    2004-07-27

    Although a consensus has emerged that an HIV vaccine should elicit a cytotoxic T lymphocyte (CTL) response, the characteristics of an effective vaccine-induced T lymphocyte response remain unclear. We explored this issue in the simian human immunodeficiency virus/rhesus monkey model in the course of assessing the relative immunogenicity of vaccine regimens that included a cytokine-augmented plasmid DNA prime and a boost with DNA or recombinant pox vectors. Recombinant vaccinia virus, recombinant modified vaccinia Ankara (MVA), and recombinant fowlpox were comparable in their immunogenicity. Moreover, whereas the magnitude of the peak vaccine-elicited T lymphocyte responses in the recombinant pox virus-boosted monkeys was substantially greater than that seen in the monkeys immunized with plasmid DNA alone, the magnitudes of recombinant pox boosted CTL responses decayed rapidly and were comparable to those of the DNA-alone-vaccinated monkeys by the time of viral challenge. Consistent with these comparable memory T cell responses, the clinical protection seen in all groups of experimentally vaccinated monkeys was similar. This study, therefore, indicates that the steady-state memory, rather than the peak effector vaccine-elicited T lymphocyte responses, may be the critical immune correlate of protection for a CTL-based HIV vaccine.

  7. The tax gene of human T-cell leukemia virus type 2 is essential for transformation of human T lymphocytes.

    PubMed

    Ross, T M; Pettiford, S M; Green, P L

    1996-08-01

    The mechanism of human T-cell leukemia virus (HTLV)-mediated transformation and induction of malignancy is unknown; however, several studies have implicated the viral gene product, Tax. Conclusive evidence for the role of Tax in the HTLV malignant process has been impeded by the inability to mutate tax in the context of an infectious virus and dissociate viral replication from cellular transformation. To circumvent this problem we constructed a mutant of HTLV type 2 (HTLV-2) that replicates by a Tax-independent mechanism. For these studies, the Tax response element in the viral long terminal repeat was replaced with the cytomegalovirus immediate-early promoter enhancer (C-enh). Transcription of the chimeric HTLV-2 (HTLVC-enh) was efficiently directed by this heterologous promoter. Also, the chimeric virus transformed primary human T lymphocytes with an efficiency similar to that of wild-type HTLV-2. A tax-knockout virus, termed HTLVC-enhDeltaTax, was constructed to directly assess the importance of Tax in cellular transformation. Transfection and infection studies indicated that HTLVC-enhDeltaTax was replication competent; however, HTLVC-enhDeltaTax failed to transform primary human T lymphocytes. We conclude that Tax is essential for HTLV-mediated transformation of human T lymphocytes. Furthermore, this chimeric HTLV, that replicates in the absence of Tax, should facilitate studies to determine the precise mechanism of T-lymphocyte transformation by HTLV.

  8. Human T-lymphotropic virus type I-associated myelopathy and tax gene expression in CD4+ T lymphocytes.

    PubMed

    Moritoyo, T; Reinhart, T A; Moritoyo, H; Sato, E; Izumo, S; Osame, M; Haase, A T

    1996-07-01

    Infection by human T-lymphotropic virus type I (HTLV-I) is associated with adult T-cell leukemia and a slowly progressive disease of the central nervous system (CNS), HTLV-I-associated myelopathy/tropical spastic paraparesis, characterized pathologically by inflammation and white matter degeneration in the spinal cord. One of the explanations for the tissue destruction is that HTLV-I infects cells in the CNS, or HTLV-I-infected CD4+ T lymphocytes enter the CNS, and this drives local expansion of virus-specific CD8+ cytotoxic T lymphocytes, which along with cytokines cause the pathological changes. Because both in the circulation and in the cerebrospinal fluid, CD8+ cytotoxic T lymphocytes are primarily reactive to the product of the HTLV-I tax gene, we sought evidence of expression of this gene within cells in the inflammatory lesions. After using double-label in situ hybridization techniques, we now report definitive localization of HTLV-I tax gene expression in CD4+ T lymphocytes in areas of inflammation and white matter destruction. These findings lend support to a hypothetical scheme of neuropathogenesis in which HTLV-I tax gene expression provokes and sustains an immunopathological process that progressively destroys myelin and axons in the spinal cord.

  9. Classical scrapie prions are associated with peripheral blood monocytes and T-lymphocytes from naturally infected sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Classical scrapie is a transmissible spongiform encephalopathy that affects sheep and goats. As detected by enzyme-linked immunoassay, previous studies suggested scrapie prions in the blood of sheep might be associated with B lymphocytes but not with monocytes or T lymphocytes. The association of sc...

  10. Polarization of T Lymphocytes Is Regulated by Mesenchymal Stem Cells in NZBWF1 and BALB/c Mice

    PubMed Central

    Sun, Lingyun; Liang, Jun; Li, Hui; Hou, Yayi

    2007-01-01

    Mesenchymal stem cells (MSCs) have been shown to suppress proliferation and activation of T lymphocytes in vivo and in vitro although the molecular mechanism of the immunosuppressive effect is not completely understood. To investigate the immunoregulatory effects of mice bone marrow mesenchymal stem cells on T lymphocyte, MSCs from NZBWF1 and BALB/c mice were isolated and expanded from bone marrow, and identified with cell morphology and the surface phenotypes. CD3+ T lymphocytes isolated by nylon wool columns were co-cultured with PMA with or without the two strains of MSCs. Then T cell apoptosis and intercellular cytokines of T cell were assessed by flow cytometry. Quantification of transcription factors T-box (T-bet) and GATA-binding protein 3 (GATA-3) expressed in T cells was detected by RT-PCR and western blot. Our results showed that there was a decrease of CD3+ T cell apoptosis when NW MSCs or Bc MSCs were added, and an increase of Th2 subset by NW MSCs and Th1 subset by Bc MSCs were observed by co-culturing MSCs with T lymphocytes. It is suggested that, by favoring Th1-cell development and inhibitory Th2-cell development, normal MSCs might interfere with the SLE development, and that marrow-derived NW MSCs had defective immunoregulatory function when compared with MSCs from healthy mouse strains.

  11. 1α,25(OH)2 Vitamin D3 Modulates Avian T Lymphocyte Functions without Inducing CTL Unresponsiveness

    PubMed Central

    Boodhoo, Nitish; Sharif, Shayan; Behboudi, Shahriar

    2016-01-01

    1,25-Dihydroxyvitamin D3 (Vitamin D) is a naturally synthesized fat soluble vitamin shown to have immunomodulatory, anti-inflammatory and cancer prevention properties in human and murine models. Here, we studied the effects of Vitamin D on the functional abilities of avian T lymphocytes using chicken Interferon (IFN)-γ ELISPOT assay, BrdU proliferation assay, Annexin V apoptosis assay and PhosFlow for detecting phosphorylated signalling molecules. The results demonstrate that Vitamin D significantly inhibited the abilities of T lymphocytes to produce IFN-γ and proliferate in vitro (P≤0.05), but retained their ability to undergo degranulation, which is a maker for cytotoxicity of these cells. Similarly, Vitamin D did not inhibit Extracellular signal-Regulated Kinase (ERK) 1/2 phosphorylation, a key mediator in T cell signalling, in the stimulated T lymphocytes population, while reduced ERK1/2 phosphorylation levels in the unstimulated cells. Our data provide evidence that Vitamin D has immuno-modulatory properties on chicken T lymphocytes without inducing unresponsiveness and by limiting immuno-pathology can promote protective immunity against infectious diseases of poultry. PMID:26910045

  12. Gamma interferon activates a previously undescribed Ca2+ influx in T lymphocytes from patients with multiple sclerosis.

    PubMed Central

    Martino, G; Clementi, E; Brambilla, E; Moiola, L; Comi, G; Meldolesi, J; Grimaldi, L M

    1994-01-01

    Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system. The etiology of the disease is still unknown. Activated T lymphocytes are considered essential in mediating the inflammatory process leading to demyelination in MS. They operate through a complex network of cytokines among which gamma interferon (gamma-IFN) plays a key role. Here we report that exposure to gamma-IFN of T lymphocytes from patients with MS activates, by a protein kinase C-mediated pathway, a previously undescribed gamma-IFN-activated Ca2+ influx, functionally coupled to the gamma-IFN receptor. The influx mainly expressed by CD4+ T lymphocytes, was found in 12 of 15 (80%) patients with clinically active MS and in 14 of 30 (46%) patients with stable MS. The influx was found in only 3 of 24 (12%) control patients and in none of the 15 healthy subjects studied. Our results document the appearance in MS lymphocytes of a gamma-IFN-activated, protein kinase C-dependent, Ca2+ influx that might be due to the expression of a new cation-specific plasmalemma channel. This finding suggests that at least part of gamma-IFN's contribution to the pathogenesis of MS is exerted through a Ca(2+)-dependent regulation of T lymphocyte activity. PMID:8197142

  13. Effect of CD4+ T lymphocyte depletion on resistance of Gulf Coast Native lambs to Haemonchus contortus infection.

    PubMed

    Peña, M T; Miller, J E; Horohov, D W

    2006-06-15

    It has been reported that CD4(+) T lymphocytes are important in acquired immunity to gastrointestinal nematode infection. Whether these lymphocytes are also involved in the immune response of naturally resistant Gulf Coast Native (GCN) sheep to Haemonchus contortus infection remains to be defined. The objective of this study was to determine the role of CD4(+) T lymphocytes in this resistance. Ten GCN lambs were randomly assigned to a control (n=5) or a treatment (n=5) group. The treatment consisted of a series of IV injections with mouse anti-ovine CD4(+) T lymphocyte monoclonal antibodies for a period of 3 weeks. After the second treatment, all lambs were experimentally infected with 10,000 H. contortus infective larvae by oral inoculation. All lambs were monitored for fecal egg counts, blood packed cell volumes, white blood cell differential counts and serum antibody responses on a weekly basis. Fluorescence-activated cell sorter (FACS) analysis was done biweekly to enumerate CD4(+) T lymphocytes in peripheral blood. Necropsies were performed at the end of the study and 10% of the contents of the gastrointestinal tract were preserved for nematode enumeration and identification. Also at necropsy, mesenteric lymph nodes were extracted and FACS analysis was run on lymphoid cells. Mean fecal egg counts on day 21 and 28 post-infection and nematode counts at necropsy of the treated group were significantly (p<0.05) higher than that of the control group. Percent CD4(+) T lymphocytes in peripheral blood was significantly (p<0.05) lower in the treatment group than in the control group from day 9 to the end of the study. No differences were found in blood packed cell volumes, white blood cell differential counts, antibody titer or lymph node CD4(+) lymphocytes between groups. Lambs depleted of their CD4(+) T lymphocytes were more susceptible to H. contortus infection than undepleted lambs. The results of this study suggest that CD4(+) T lymphocytes are associated with the

  14. CD161 Expression Defines a Th1/Th17 Polyfunctional Subset of Resident Memory T Lymphocytes in Bronchoalveolar Cells

    PubMed Central

    Gonzalez, Yolanda; Herrera, María Teresa; Juárez, Esmeralda; Salazar-Lezama, Miguel Angel; Bobadilla, Karen; Torres, Martha

    2015-01-01

    Alveolar resident memory T cells (TRM) comprise a currently uncharacterized mixture of cell subpopulations. The CD3+CD161+ T cell subpopulation resides in the liver, intestine and skin, but it has the capacity for tissue migration; however, the presence of resident CD3+CD161+ T cells in the bronchoalveolar space under normal conditions has not been reported. Bronchoalveolar cells (BACs) from healthy volunteers were evaluated and found that 8.6% (range 2.5%-21%) of these cells were CD3+ T lymphocytes. Within the CD3+ population, 4.6% of the cells (2.1–11.3) expressed CD161 on the cell surface, and 74.2% of the CD161+CD3+ T cells expressed CD45RO. The number of CD3+CD161+ T cells was significantly lower in the bronchoalveolar space than in the blood (4.6% of BACs vs 8.4% of peripheral blood mononuclear cells (PBMCs); P<0.05). We also found that 2.17% of CD4+ T lymphocytes and 1.52% of CD8+ T lymphocytes expressed CD161. Twenty-two percent of the alveolar CD3+CD161+ T lymphocytes produced cytokines upon stimulation by PMA plus ionomycin, and significantly more interferon gamma (IFN-γ) was produced compared with other cytokines (P = 0.05). Most alveolar CD3+CD161+ T cells produced interleukin-17 (IL-17) and IFN-γ simultaneously, and the percentage of these cells was significantly higher than the percentage of CD3+CD161− T cells. Moreover, the percentage of alveolar CD3+CD161+ T lymphocytes that produced IFN-γ/IL-17 was significantly higher than those in the peripheral blood (p<0.05). In conclusion, Th1/Th17-CD3+CD161+ TRM could contribute to compartment-specific immune responses in the lung. PMID:25906076

  15. Desialylation of T lymphocytes overcomes the monocyte dependency of pokeweed mitogen-induced T-cell activation.

    PubMed Central

    Gallart, T; Angel de la Fuente, M; Josep Barceló, J; Alberola-Ila, J; Lozano, F

    1997-01-01

    Activation of T lymphocytes by pokeweed mitogen (PWM) is strictly monocyte (Mo)-dependent and results in T-cell mitogenesis and interleukin-2 (IL-2) secretion, coupled with an inability to utilize IL-2 due to an impaired expression of functional IL-2 receptor (IL-2R). Such IL-2R impairment could arise in PWM-activated T cells themselves or, alternatively, be the result of Mo-derived influences, as it is known that PWM binds Mo strongly and does not or poorly binds lymphocytes, and Mo becomes rapidly destroyed in PWM-stimulated cultures of blood mononuclear cells or T cells plus Mo. The present study investigated these possibilities. The results show for the first time that desialylation of T lymphocytes strongly increases their PWM-binding capacity and, in addition, overcomes the Mo requirement for PWM to induce T-cell mitogenesis and IL-2 secretion. Such secreted IL-2 levels were even higher that those found in cultures of Mo-dependent PWM-activated T lymphocytes but similarly to the latter, PWM-activated desialylated purified T lymphocytes exhibited negligible high-affinity IL-2 binding capacity and an inability to utilize the IL-2 they produced. These effects were not due to desialylation itself, as indicated by data obtained with peanut agglutinin, a lectin that becomes strongly reactive with desialylated T lymphocytes. The data clearly indicate the existence of PWM-related events capable of impairing the expression of functional IL-2R without affecting IL-2 secretion, and indicate that such events are due to mechanisms arising at the level of PWM-activated T cells themselves. Images Figure 3 PMID:9038713

  16. Multiple In Vitro and In Vivo Regulatory Effects of Budesonide in CD4+ T Lymphocyte Subpopulations of Allergic Asthmatics

    PubMed Central

    Pace, Elisabetta; Di Sano, Caterina; La Grutta, Stefania; Ferraro, Maria; Albeggiani, Giuseppe; Liotta, Giuseppe; Di Vincenzo, Serena; Uasuf, Carina Gabriela; Bousquet, Jean; Gjomarkaj, Mark

    2012-01-01

    Background Increased activation and increased survival of T lymphocytes characterise bronchial asthma. Objectives In this study the effect of budesonide on T cell survival, on inducible co-stimulator T cells (ICOS), on Foxp3 and on IL-10 molecules in T lymphocyte sub-populations was assessed. Methods Cell survival (by annexin V binding) and ICOS in total lymphocytes, in CD4+/CD25+ and in CD4+/CD25- and Foxp3 and IL-10 in CD4+/CD25+ and in CD4+/CD25-cells was evaluated, by cytofluorimetric analysis, in mild intermittent asthmatics (n = 19) and in controls (n = 15). Allergen induced T lymphocyte proliferation and the in vivo effects of budesonide in mild persistent asthmatics (n = 6) were also explored. Results Foxp3 was reduced in CD4+/CD25- and in CD4+/CD25+ cells and ICOS was reduced in CD4+/CD25+ cells but it was increased in CD4+CD25-in asthmatics when compared to controls. In asthmatics, in vitro, budesonide was able to: 1) increase annexin V binding and to reduce ICOS in total lymphocytes; 2) increase annexin V binding and Foxp3 and to reduce ICOS in CD4+/CD25- cells; 3) reduce annexin V binding and to increase IL-10 and ICOS in CD4+/CD25+ cells; 4) reduce cell allergen induced proliferation. In vivo, budesonide increased ICOS in CD4+/CD25+ while it increased Foxp3 and IL-10 in CD4+/CD25+ and in CD4+/CD25- cells. Conclusions Budesonide modulates T cell survival, ICOS, Foxp3 and IL-10 molecules differently in T lymphocyte sub-populations. The findings provided shed light on new mechanisms by which corticosteroids, drugs widely used for the clinical management of bronchial asthma, control T lymphocyte activation. PMID:23251336

  17. CD4+/CD25+ T-Lymphocytes and Th1/Th2 regulation in dilated cardiomyopathy

    PubMed Central

    Efthimiadis, I; Skendros, P; Sarantopoulos, A; Boura, P

    2011-01-01

    Objective: Autoimmune mechanisms are often involved in the pathogenesis of Dilated Cardiomyopathy (DCM) and Th1 immune response against cardiac antigens plays a pivotal role in disease development. Methods: IL-2 receptor (CD4+/CD25+) and cytokines IL-2, IFN-γ, IL-10 were studied in 42 patients (17 with DCM - DCM group, 10 patients with hypertrophic cardiac disease - HCD group, and 15 healthy volunteers - Control group). DCM group was subdivided in: DCM-1 (9 patients with recent disease onset) and DCM-2 (8 patients with chronic DCM). The % CD4+/CD25+ T-lymphocytes were analyzed by double fluorescence flow cytometry both ex vivo and after phytohaemagglutinin (PHA)-cultures with/without 5 and 10 microgr of human cardiac myosin. The cytokines were measured using Enzyme-Linked Immunosorbant Assay (ELISA) method. Results: Ex vivo analysis: In DCM group, CD4+/CD25+ T-cells significantly increased compared to other groups (p<0.05), due exclusively to DCM-2 subgroup (p=0.019). In PHA cultures in DCM-2 subgroup CD4+/CD25+ T-lymphocytes were significantly increased compared to all other groups (p<0.001). The addition of myosin in the cultures of DCM-2 subgroup maintained the same result. In cultures supernatants in DCM-2 subgroup, IL-2 levels were impressively increased compared to DCM-1 subgroup (p=5.91x10-6), HCD and Control groups (p<0.001). Addition of antigen decreased significantly IL-2 levels in DCM-2 subgroup (p=0.01). IFN-γ levels followed the same pattern of alterations. IL-10 levels were significantly increased in both DCM subgroups compared to HCD and Control groups (p<0.05). Conclusions: Increased peripheral CD4+/CD25+ T-cells found in chronic DCM could be a useful prognostic marker in DCM progress. Increased synthesis of IL-2 and IFN-γ and varying IL-10 levels reflects a Th1 pattern of immune response during chronic disease and implies active cellular immunity process, related to poor prognosis. Thus, analysis of the Th1/Th2 phenotype may be useful in disease

  18. Effects of ISS equivalent ionizing radiation dose on Human T-lymphocytes

    NASA Astrophysics Data System (ADS)

    Meloni, Maria Antonia; Pani, Giuseppe; Benotmane, Rafi; Mastroleo, Felice; Aboul-El-Ardat, Khalil; Janssen, Ann; Leysen, Liselotte; Vanhavere, Filip; Leys, Natalie; Galleri, Grazia; Pippia, Proto; Baatout, Sarah

    One of the objectives of the current international space programs is to investigate the effects of cosmic environment on Humans. It is known that during a long exposure to the space conditions, including ionizing radiations and microgravity, the immune system of the astronauts is impaired. In past years several experiments were performed to identify responsible factors of in vitro mitogenic activation process in human T-lymphocytes under simulated microgravity effect and during dedicated space missions. It come out that the lack of immune response in microgravity occurs at the cellular and molecular level. In order to evaluate effects on pure primary T-lymphocytes from peripheral blood exposed to International Space Station (ISS)-like ionizing radiation, we applied a mixture of Cesium-137, as representative of low energy particles, and Californium-252, as representative of hight energy particles, with rate similar to those monitored inside the ISS during previous space mission (Goossens et all. 2006). This facility is available at SCK•CEN (Belgium) (Mastroleo et al., 2009). Although the dose received by the cells was relatively low, flow cytometry analysis 24 hours after irradiation showed a decrease in cell viability coupled with the increase of the caspase-3 activity. However, Bcl-2 activity did not seem to be affected by the radiation. Furthermore, activation of cells induced an increase of the cell size and alteration of cellular morphology. Cell cycle as well as 8-oxo-G were also modified upon radiation and activation. Gene expression analysis shows a modulation of genes rather as a consequence of exposure than with the activation status. 330 genes have been identified to be significantly modulated in function of the time and have been grouped in four different cluster representing significant expression profiles. Preliminary functional analysis shows mainly genes involved in the immune response and inflammatory diseases as well as oxidative stress and

  19. Calcineurin phosphatase activity in T lymphocytes is inhibited by FK 506 and cyclosporin A.

    PubMed Central

    Fruman, D A; Klee, C B; Bierer, B E; Burakoff, S J

    1992-01-01

    The immunosuppressive agents cyclosporin A (CsA) and FK 506 bind to distinct families of intracellular proteins (immunophilins) termed cyclophilins and FK 506-binding proteins (FKBPs). Recently, it has been shown that, in vitro, the complexes of CsA-cyclophilin and FK 506-FKBP-12 bind to and inhibit the activity of calcineurin, a calcium-dependent serine/threonine phosphatase. We have investigated the effects of drug treatment on phosphatase activity in T lymphocytes. Calcineurin is expressed in T cells, and its activity can be measured in cell lysates. Both CsA and FK 506 specifically inhibit cellular calcineurin at drug concentrations that inhibit interleukin 2 production in activated T cells. Rapamycin, which binds to FKBPs but exhibits different biological activities than FK 506, has no effect on calcineurin activity. Furthermore, excess concentrations of rapamycin prevent the effects of FK 506, apparently by displacing FK 506 from FKBPs. These results show that calcineurin is a target of drug-immunophilin complexes in vivo and establish a physiological role for calcineurin in T-cell activation. Images PMID:1373887

  20. IL-10 is excluded from the functional cytokine memory of human CD4+ memory T lymphocytes.

    PubMed

    Dong, Jun; Ivascu, Claudia; Chang, Hyun-Dong; Wu, Peihua; Angeli, Roberta; Maggi, Laura; Eckhardt, Florian; Tykocinski, Lars; Haefliger, Carolina; Möwes, Beate; Sieper, Jochen; Radbruch, Andreas; Annunziato, Francesco; Thiel, Andreas

    2007-08-15

    Epigenetic modifications, including DNA methylation, profoundly influence gene expression of CD4(+) Th-specific cells thereby shaping memory Th cell function. We demonstrate here a correlation between a lacking fixed potential of human memory Th cells to re-express the immunoregulatory cytokine gene IL10 and its DNA methylation status. Memory Th cells secreting IL-10 or IFN-gamma were directly isolated ex vivo from peripheral blood of healthy volunteers, and the DNA methylation status of IL10 and IFNG was assessed. Limited difference in methylation was found for the IL10 gene locus in IL-10-secreting Th cells, as compared with Th cells not secreting IL-10 isolated directly ex vivo or from in vitro-established human Th1 and Th2 clones. In contrast, in IFN-gamma(+) memory Th cells the promoter of the IFNG gene was hypomethylated, as compared with IFN-gamma-nonsecreting memory Th cells. In accordance with the lack of epigenetic memory, almost 90% of ex vivo-isolated IL-10-secreting Th cells lacked a functional memory for IL-10 re-expression after restimulation. Our data indicate that IL10 does not become epigenetically marked in human memory Th cells unlike effector cytokine genes such as IFNG. The exclusion of IL-10, but not effector cytokines, from the functional memory of human CD4(+) T lymphocytes ex vivo may reflect the need for appropriate regulation of IL-10 secretion, due to its potent immunoregulatory potential.

  1. A Gene Encoding Antigenic Peptides of Human Squamous Cell Carcinoma Recognized by Cytotoxic T Lymphocytes

    PubMed Central

    Shichijo, Shigeki; Nakao, Masanobu; Imai, Yasuhisa; Takasu, Hideo; Kawamoto, Mayumi; Niiya, Fumihiko; Yang, Damu; Toh, Yuji; Yamana, Hideaki; Itoh, Kyogo

    1998-01-01

    Except for melanomas, tumor antigens recognized by cytotoxic T lymphocytes (CTLs) are yet unidentified. We have identified a gene encoding antigenic peptides of human squamous cell carcinomas (SCCs) recognized by human histocompatibility leukocyte antigens (HLA)- A2601–restricted CTLs. This gene showed no similarity to known sequences, and encoded two (125- and 43-kilodalton [kD]) proteins. The 125-kD protein with the leucine zipper motif was expressed in the nucleus of the majority of proliferating cells tested, including normal and malignant cells. The 43-kD protein was expressed in the cytosol of most SCCs from various organs and half of lung adenocarcinomas, but was not expressed in other cancers nor in a panel of normal tissues. The three nonapeptides shared by the two proteins were recognized by the KE4 CTLs, and one of the peptides induced in vitro from peripheral blood mononuclear cells (PBMCs) the CTLs restricted to the autologous tumor cells. The 43-kD protein and this nonapeptide (KGSGKMKTE) may be useful for the specific immunotherapy of HLA-A2601+ epithelial cancer patients. PMID:9449708

  2. Raman spectrum reveals the cell cycle arrest of Triptolide-induced leukemic T-lymphocytes apoptosis

    NASA Astrophysics Data System (ADS)

    Zhang, Daosen; Feng, Yanyan; Zhang, Qinnan; Su, Xin; Lu, Xiaoxu; Liu, Shengde; Zhong, Liyun

    2015-04-01

    Triptolide (TPL), a traditional Chinese medicine extract, possesses anti-inflammatory and anti-tumor properties. Though some research results have implicated that Triptolide (TPL) can be utilized in the treatment of leukemia, it remains controversial about the mechanism of TPL-induced leukemic T-lymphocytes apoptosis. In this study, combining Raman spectroscopic data, principal component analysis (PCA) and atomic force microscopy (AFM) imaging, both the biochemical changes and morphological changes during TPL-induced cell apoptosis were presented. In contrast, the corresponding data during Daunorubicin (DNR)-induced cell apoptosis was also exhibited. The obtained results showed that Raman spectral changes during TPL-induced cell apoptosis were greatly different from DNR-induced cell apoptosis in the early stage of apoptosis but revealed the high similarity in the late stage of apoptosis. Moreover, above Raman spectral changes were respectively consistent with the morphological changes of different stages during TPL-induced apoptosis or DNR-induced apoptosis, including membrane shrinkage and blebbing, chromatin condensation and the formation of apoptotic bodies. Importantly, it was found that Raman spectral changes with TPL-induced apoptosis or DNR-induced apoptosis were respectively related with the cell cycle G1 phase arrest or G1 and S phase arrest.

  3. Metabolic Maintenance of Cell Asymmetry following Division in Activated T Lymphocytes

    PubMed Central

    Verbist, Katherine C.; Guy, Cliff S; Milasta, Sandra; Liedmann, Swantje; Kamiński, Marcin M.; Wang, Ruoning; Green, Douglas R.

    2016-01-01

    Asymmetric cell division (ACD)—the partitioning of cellular components in response to polarizing cues during mitosis—plays roles in differentiation and development1. ACD is important for the self-renewal of neuroblasts in C. elegans and fertilized zygotes in Drosophila, and participates in the development of mammalian nervous and digestive systems1. T lymphocytes, upon activation by antigen-presenting cells (APC), can undergo ACD, wherein the daughter cell proximal to the APC is more likely to differentiate into an effector-like T cell and the distal daughter more likely to differentiate into a memory-like T cell2. Upon activation and prior to cell division, expression of the transcription factor c-Myc drives metabolic reprogramming, necessary for the subsequent proliferative burst3. We found that during the first division of an activated T cell, c-Myc can sort asymmetrically. Asymmetric amino acid transporter distribution, amino acid content, and TORC1 function correlate with c-Myc expression, and both amino acids and TORC1 activity sustain the differences in c-Myc expression in one daughter over the other. Asymmetric c-Myc levels in daughter T cells affect proliferation, metabolism, and differentiation, and these effects are altered by experimental manipulation of TORC1 activity or Myc expression. Therefore, metabolic signaling pathways cooperate with transcription programs to maintain differential cell fates following asymmetric T cell division. PMID:27064903

  4. Sp1 transcriptional activity is up-regulated by phosphatase 2A in dividing T lymphocytes.

    PubMed

    Lacroix, Isabelle; Lipcey, Carol; Imbert, Jean; Kahn-Perlès, Brigitte

    2002-03-15

    We have followed Sp1 expression in primary human T lymphocytes induced, via CD2 plus CD28 costimulation, to sustained proliferation and subsequent return to quiescence. Binding of Sp1 to wheat germ agglutinin lectin was not modified following activation, indicating that the overall glycosylation of the protein was unchanged. Sp1 underwent, instead, a major dephosphorylation that correlated with cyclin A expression and, thus, with cell cycle progression. A similar change was observed in T cells that re-entered cell cycle following secondary interleukin-2 stimulation, as well as in serum-induced proliferating NIH/3T3 fibroblasts. Phosphatase 2A (PP2A) appears involved because 1) treatment of dividing cells with okadaic acid or cantharidin inhibited Sp1 dephosphorylation and 2) PP2A dephosphorylated Sp1 in vitro and strongly interacted with Sp1 in vivo. Sp1 dephosphorylation is likely to increase its transcriptional activity because PP2A overexpression potentiated Sp1 site-driven chloramphenicol acetyltransferase expression in dividing Kit225 T cells and okadaic acid reversed this effect. This increase might be mediated by a stronger affinity of dephosphorylated Sp1 for DNA, as illustrated by the reduced DNA occupancy by hyperphosphorylated Sp factors from cantharidin- or nocodazole-treated cells. Finally, Sp1 dephosphorylation appears to occur throughout cell cycle except for mitosis, a likely common feature to all cycling cells.

  5. Development of a cytotoxic T-lymphocyte-based, broadly protective influenza vaccine.

    PubMed

    Uchida, Tetsuya

    2011-01-01

    The current vaccination strategy against influenza is to induce production of antibodies directed against the surface antigens of these viruses. However, frequent changes in the surface antigens of influenza viruses allow them to avoid antibody-mediated immunity. On the other hand, it is known that cytotoxic T-lymphocyte (CTL) populations directed against internal antigens of influenza A virus are broadly cross-reactive to influenza virus subtypes. The present authors have previously demonstrated that antigens chemically coupled to the surface of liposomes made using unsaturated fatty acids are cross-presented by APCs via MHC class I to CD8(+) T cells and induce antigen-specific CTLs. Based on this finding, a liposome vaccine that is capable of inducing CTL response against internal antigens of influenza viruses and removing virus-infected cells in the host has been developed. The CTL-based liposomal technique might be applicable for developing vaccines against influenza and other viruses, such as hepatitis C, HIV, and severe acute respiratory syndrome corona virus, which frequently change their surface antigenic molecules.

  6. Human immunodeficiency virus (HIV)-specific cytotoxic T lymphocyte activity in HIV-exposed seronegative persons.

    PubMed

    Bernard, N F; Yannakis, C M; Lee, J S; Tsoukas, C M

    1999-03-01

    Repeated exposure to human immunodeficiency virus (HIV) does not always result in seroconversion. Understanding the conditions that permit or protect against progressive infection with HIV is important for vaccine development. Nineteen subjects at risk for HIV infection were CCR-5 genotyped and screened for virus-specific memory cytotoxic T lymphocytes (CTL). None had the Delta32CCR-5/Delta32CCR-5 genotype associated with HIV resistance. HIV-specific CTL were detected in 7 (41.1%) of 17 exposed uninfected subjects versus 0 of 14 seronegative subjects with no HIV risk factors (P=.006, chi2 test). Recognition of virus by CTL in exposed uninfected subjects was major histocompatibility complex class I-restricted and multispecific, and specificity could change with time. Activity could persist up to 34 months after the last virus exposure. The presence of HIV-specific CTL in a greater proportion of seronegative HIV-exposed versus unexposed subjects supports the notion that in some cases, virus exposure induces HIV immunity without seroconversion or disease progression.

  7. In Situ Activation of Pituitary-Infiltrating T Lymphocytes in Autoimmune Hypophysitis

    PubMed Central

    Lin, Han-Huei; Gutenberg, Angelika; Chen, Tzu-Yu; Tsai, Nu-Man; Lee, Chia-Jung; Cheng, Yu-Che; Cheng, Wen-Hui; Tzou, Ywh-Min; Caturegli, Patrizio; Tzou, Shey-Cherng

    2017-01-01

    Autoimmune hypophysitis (AH) is a chronic inflammatory disease characterized by infiltration of T and B lymphocytes in the pituitary gland. The mechanisms through which infiltrating lymphocytes cause disease remain unknown. Using a mouse model of AH we assessed whether T lymphocytes undergo activation in the pituitary gland. Infiltrating T cells co-localized with dendritic cells in the pituitary and produced increased levels of interferon-γ and interleukin-17 upon stimulation in vitro. Assessing proliferation of CD3- and B220-postive lymphocytes by double immunohistochemistry (PCNA-staining) and flow cytometry (BrdU incorporation) revealed that a discrete proportion of infiltrating T cells and B cells underwent proliferation within the pituitary parenchyma. This proliferation persisted into the late disease stage (day 56 post-immunization), indicating the presence of a continuous generation of autoreactive T and B cells within the pituitary gland. T cell proliferation in the pituitary was confirmed in patients affected by autoimmune hypophysitis. In conclusion, we show that pituitary-infiltrating lymphocytes proliferate in situ during AH, providing a previously unknown pathogenic mechanism and new avenues for treatment. PMID:28262761

  8. Tissue Dimensionality Influences the Functional Response of Cytotoxic T Lymphocyte-Mediated Killing of Targets

    PubMed Central

    Gadhamsetty, Saikrishna; Marée, Athanasius F. M.; de Boer, Rob J.; Beltman, Joost B.

    2017-01-01

    Cytotoxic T lymphocyte (CTL)-mediated killing of virus infections and tumors occurs over a wide range of conditions. The spatial environments in which CTLs encounter target cells vary from narrow vessels, to two-dimensional epithelial tissues, to densely populated 3-dimensional (3D) T cell areas within lymphoid tissues. How such spatial environments alter the functional response of CTL-mediated killing, i.e., how the killing efficiency depends on cell densities, is unclear. In this study, we perform cellular Potts model simulations in different spatial configurations to investigate how the dimensionality of the space affects the functional response of CTL-mediated killing. Irrespective of the spatial configuration, the function with separate saturation constants for CTL and for target cell densities that we previously proposed can in all cases describe the response, demonstrating its generality. However, the tissue dimensionality determines at which cell densities the killing rate starts to saturate. We show that saturation in a fully 3D environment is stronger than in a “flat” 3D environment, which is largely due to accompanying differences in the CTL–target encounter rates. PMID:28123385

  9. Suppression of T-lymphocyte responses to Entamoeba histolytica antigen by immune sera.

    PubMed Central

    Salata, R A; Martinez-Palomo, A; Canales, L; Murray, H W; Trevino, N; Ravdin, J I

    1990-01-01

    Lymphocytes from patients cured of amebic liver abscesses proliferate and produce gamma interferon upon incubation with soluble Entamoeba histolytica antigen: however, amebic liver abscesses exhibit a relentless progression without treatment. To determine whether suppressive factors are present in sera, we studied T-lymphocyte responses to total soluble E. histolytica antigen by using cells from five patients treated for amebic liver abscesses in the presence of 15 different immune sera and 10 control sera. In the presence of immune sera, E. histolytica antigen-induced lymphocyte proliferation decreased by 63% and production of gamma interferon was reduced by 93.2% (P less than 0.01). Immune sera had no effect on the mitogenic responses of patient lymphocytes to phytohemagglutinin or on the proliferative responses of control lymphocytes to phytohemagglutinin or tetanus toxoid. The suppressive activity of immune sera diminished as the time between therapy for amebic liver abscesses and serum collection increased (P less than 0.05). Suppressive activity did not correlate with the titers of serum anti-amebic antibody and was not affected when serum was absorbed with viable amebic trophozoites. In conclusion, soluble factors present in the sera of amebic liver abscess patients suppressed in vitro lymphocyte responses to E. histolytica antigen and may have contributed to the lack of development of effective in vivo cell-mediated immune responses following the onset of amebic liver abscesses. Images PMID:2123828

  10. A new theory of cytotoxic T-lymphocyte memory: implications for HIV treatment.

    PubMed Central

    Wodarz, D; Page, K M; Arnaout, R A; Thomsen, A R; Lifson, J D; Nowak, M A

    2000-01-01

    We use simple mathematical models to examine the dynamics of primary and secondary cytotoxic T-lymphocyte (CTL) responses to viral infections. In particular, we are interested in conditions required to resolve the infection and to protect the host upon secondary challenge. While protection against reinfection is only effective in a restricted set of circumstances, we find that resolution of the primary infection requires persistence of CTL precursors (GTLp), as well as a fast rate of activation of the CTLp. Since these are commonly the defining characteristics of CTL memory, we propose that CTL memory may have evolved in order to clear the virus during primary challenge. We show experimental data from lymphocytic choriomeningitis virus infection in mice, supporting our theory on CTL memory. We adapt our models to HIV and find that immune impairment during the primary phase of the infection may result in the failure to establish CTL memory which in turn leads to viral persistence. Based on our models we suggest conceptual treatment regimes which ensure establishment of CTL memory. This would allow the immune response to control HIV in the long term in the absence of continued therapy. PMID:10794051

  11. cAMP inducibility of transcriptional repressor ICER in developing and mature human T lymphocytes.

    PubMed Central

    Bodor, J; Spetz, A L; Strominger, J L; Habener, J F

    1996-01-01

    Stimulation of the cAMP-dependent signaling pathway exerts an inhibitory effect on the proliferation and effector functions of T cells. The ability of T cells to form high intracellular levels of cAMP is acquired during development in the human thymus and is retained by the majority of mature peripheral T lymphocytes. Here we show that elevated cAMP levels in T cells correlate with the expression of the potent transcriptional repressor ICER (inducible cAMP early repressor) previously described in the hypothalamic-pituitary-gonadal axis. Further, in transcriptional assays in vivo, ICER inhibits calcineurin-mediated expression of the interleukin 2 promoter as well as Tax-mediated transactivation of the human T-lymphotropic virus type I (HTLV-I) promoter. Thus, the induction of ICER in T cells may play an important role in the cAMP-induced quiescence and the persistent latency of HTLV-I. Images Fig. 3 Fig. 4 Fig. 5 PMID:8622971

  12. Effects of Clostridium difficile toxin A and B on human T lymphocyte migration.

    PubMed

    Wu, Dan; Joyee, Antony George; Nandagopal, Saravanan; Lopez, Marianela; Ma, Xiuli; Berry, Jody; Lin, Francis

    2013-05-03

    Bacterial products such as toxins can interfere with a variety of cellular processes, leading to severe human diseases. Clostridium difficile toxins, TcdA and TcdB are the primary contributing factors to the pathogenesis of C. difficile-associated diseases (CDAD). While the mechanisms for TcdA and TcdB mediated cellular responses are complex, it has been shown that these toxins can alter chemotactic responses of neutrophils and intestinal epithelial cells leading to innate immune responses and tissue damages. The effects of C. difficile toxins on the migration and trafficking of other leukocyte subsets, such as T lymphocytes, are not clear and may have potential implications for adaptive immunity. We investigated here the direct and indirect effects of TcdA and TcdB on the migration of human blood T cells using conventional cell migration assays and microfluidic devices. It has been found that, although both toxins decrease T cell motility, only TcdA but not TcdB decreases T cell chemotaxis. Similar effects are observed in T cell migration toward the TcdA- or TcdB-treated human epithelial cells. Our study demonstrated the primary role of TcdA (compared to TcdB) in altering T cell migration and chemotaxis, suggesting possible implications for C. difficile toxin mediated adaptive immune responses in CDAD.

  13. Methamphetamine causes mitrochondrial oxidative damage in human T lymphocytes leading to functional impairment.

    PubMed

    Potula, Raghava; Hawkins, Brian J; Cenna, Jonathan M; Fan, Shongshan; Dykstra, Holly; Ramirez, Servio H; Morsey, Brenda; Brodie, Michael R; Persidsky, Yuri

    2010-09-01

    Methamphetamine (METH) abuse is known to be associated with an inordinate rate of infections. Although many studies have described the association of METH exposure and immunosuppression, so far the underlying mechanism still remains elusive. In this study, we present evidence that METH exposure resulted in mitochondrial oxidative damage and caused dysfunction of primary human T cells. METH treatment of T lymphocytes led to a rise in intracellular calcium levels that enhanced the generation of reactive oxygen species. TCR-CD28 linked calcium mobilization and subsequent uptake by mitochondria in METH-treated T cells correlated with an increase in mitochondrion-derived superoxide. Exposure to METH-induced mitochondrial dysfunction in the form of marked decrease in mitochondrial membrane potential, increased mitochondrial mass, enhanced protein nitrosylation and diminished protein levels of complexes I, III, and IV of the electron transport chain. These changes paralleled reduced IL-2 secretion and T cell proliferative responses after TCR-CD28 stimulation indicating impaired T cell function. Furthermore, antioxidants attenuated METH-induced mitochondrial damage by preserving the protein levels of mitochondrial complexes I, III, and IV. Altogether, our data indicate that METH can cause T cell dysfunction via induction of oxidative stress and mitochondrial injury as underlying mechanism of immune impairment secondary to METH abuse.

  14. Evaluation of adenosine deaminase assay for analyzing T-lymphocyte density in vitro.

    PubMed

    Kainthla, Rani Poonam; Kashyap, Rajpal Singh; Prasad, Sweta; Purohit, Hemant J; Taori, Giridhar M; Daginawala, Hatim F

    2006-01-01

    The proliferative capacity of T cells in response to various stimuli is commonly determined by radioactive assay based on incorporation of [3H]thymidine ([3H]TdR) into newly synthesized DNA. In order to assess techniques for application in laboratories where radioactive facilities are not present, an alternative method was tested. As an alternative, T-cell proliferation was measured by spectrophotometrically analyzing the presence of an enzyme adenosine deaminase in lymphocytes and also using a standard XTT assay. Jurkat (human) T-cell line (clone E6.1) was used for lymphocyte population. The Jurkat cell concentration was adjusted according to different cell densities and enzyme activity was determined. Cells were also seeded in complete medium up to 72 h and harvested for estimation of enzyme activity. A significant correlation between the standard cell-proliferation assay and adenosine deaminase assay was observed. The present study indicates that the assay of adenosine deaminase is a reliable and accurate method for measuring proliferation of T lymphocytes.

  15. Experimental Murine Candidiasis: Pathological and Immune Responses in T-Lymphocyte-Depleted Mice

    PubMed Central

    Giger, Donald K.; Domer, Judith E.; Moser, Stephen A.; McQuitty, J. T.

    1978-01-01

    Mice depleted of T-lymphocytes by thymectomy and irradiation (TXB) and immunologically competent mice were compared for gross and histological pathology as well as immune responses after cutaneous and/or intravenous challenge with Candida albicans. In response to a first cutaneous inoculation with viable Candida, TXB, sham-operated (SXB), and unmanipulated (normal) mice, all developed lesions of comparable size, duration, and histopathology. When challenged a second time cutaneously, normal and SXB mice developed lesions which were greatly increased in size when compared with those produced by a first cutaneous infection, whereas TXB mice developed lesions comparable in size to those initiated by the first infection. Histologically, the first and second lesions in all animals were acute abscesses predominantly comprised of polymorphonuclear leukocytes. The larger second lesions in SXB and normal mice were accompanied by detectable circulating antibody and by delayed hypersensitivity. Neither circulating antibody nor delayed hypersensitivity were stimulated in the TXB mice. When challenged intravenously, all previously uninfected mice, regardless of T-cell status, were equally susceptible to C. albicans. Contrary to SXB or normal mice, however, TXB mice which had been infected cutaneously were not more resistant to a subsequent intravenous challenge as judged by 6-week survival. The results suggest that T-cells do not play a significant role in innate resistance of mice to systemic candidiasis, but that such cells are important in the development of acquired resistance. PMID:309437

  16. Inorganic mercury dissociates preassembled Fas/CD95 receptor oligomers in T lymphocytes

    SciTech Connect

    Ziemba, Stamatina E.; McCabe, Michael J.; Rosenspire, Allen J. . E-mail: arosensp@sun.science.wayne.edu

    2005-08-15

    Genetically susceptible rodents exposed to low burdens of inorganic mercury (Hg{sup 2+}) develop autoimmune disease. Previous studies have shown that low, noncytotoxic levels of Hg{sup 2+} inhibit Fas-mediated apoptosis in T cells. These results suggest that inhibition of the Fas death receptor pathway potentially contributes to autoimmune disease after Hg{sup 2+} exposure, as a consequence of disruption of peripheral tolerance. The formation of active death inducing signaling complexes (DISC) following CD95/Fas receptor oligomerization is a primary step in the Fas-mediated apoptotic pathway. Other recent studies have shown that Hg{sup 2+} at concentrations that inhibit apoptosis also inhibit formation of active DISC, suggesting that inhibition of DISC is the mechanism responsible for Hg{sup 2+}-mediated inhibition of apotosis. Preassociated Fas receptors have been implicated as key elements necessary for the production of functional DISC. We present evidence in this study showing that low and nontoxic concentrations of Hg{sup 2+} induce the dissociation of preassembled Fas receptor complexes in Jurkat T cells. Thus, this Hg{sup 2+}-induced event should subsequently decrease the amount of preassembled Fas available for DISC formation, potentially resulting in the attenuation of Fas-mediated apoptosis in T lymphocytes.

  17. Loss of prolyl hydroxylase-2 in myeloid cells and T-lymphocytes impairs tumor development.

    PubMed

    Mamlouk, Soulafa; Kalucka, Joanna; Singh, Rashim Pal; Franke, Kristin; Muschter, Antje; Langer, Anika; Jakob, Christiane; Gassmann, Max; Baretton, Gustavo B; Wielockx, Ben

    2014-02-15

    The tumor microenvironment plays a pivotal role during cancer development and progression. The balance between suppressive and cytotoxic responses of the tumor immune microenvironment has been shown to have a direct effect on the final outcome in various human and experimental tumors. Recently, we demonstrated that the oxygen sensor HIF-prolyl hydroxylase-2 (PHD2) plays a detrimental role in tumor cells, stimulating systemic growth and metastasis in mice. In our current study, we show that the conditional ablation of PHD2 in the hematopoietic system also leads to reduced tumor volume, intriguingly generated by an imbalance between enhanced cell death and improved proliferation of tumor cells. This effect seems to rely on the overall downregulation of protumoral as well as antitumoral cytokines. Using different genetic approaches, we were able to confine this complex phenotype to the crosstalk of PHD2-deficient myeloid cells and T-lymphocytes. Taken together, our findings reveal a multifaceted role for PHD2 in several hematopoietic lineages during tumor development and might have important implications for the development of tumor therapies in the future.

  18. DR3 regulation of apoptosis of naive T-lymphocytes in children with acute infectious mononucleosis.

    PubMed

    Filatova, Elena Nikolaevna; Anisenkova, Elena Viktorovna; Presnyakova, Nataliya Borisovna; Utkin, Oleg Vladimirovich

    2016-09-01

    Acute infectious mononucleosis (AIM) is a widespread viral disease that mostly affects children. Development of AIM is accompanied by a change in the ratio of immune cells. This is provided by means of different biological processes including the regulation of apoptosis of naive T-cells. One of the potential regulators of apoptosis of T-lymphocytes is a death receptor 3 (DR3). We have studied the role of DR3 in the regulation of apoptosis of naive CD4(+) (nTh) and CD8(+) (nCTL) T-cells in healthy children and children with AIM. In healthy children as well as in children with AIM, the activation of DR3 is accompanied by inhibition of apoptosis of nTh. In healthy children, the stimulation of DR3 resulted in the increase in apoptosis of nCTL. On the contrary, in children with AIM, the level of apoptosis of nCTL decreased after DR3 activation, which is a positive contribution to the antiviral immune response. In children with AIM, nCTL are characterized by reduced level of apoptosis as compared with healthy children. These results indicate that DR3 can be involved in the reduction of sensitivity of nCTL to apoptosis in children with AIM.

  19. A General Functional Response of Cytotoxic T Lymphocyte-Mediated Killing of Target Cells

    PubMed Central

    Gadhamsetty, Saikrishna; Marée, Athanasius F.M.; Beltman, Joost B.; de Boer, Rob J.

    2014-01-01

    Cytotoxic T lymphocytes (CTLs) kill virus-infected cells and tumor cells, and play a critical role in immune protection. Our knowledge of how the CTL killing efficiency varies with CTL and target cell numbers is limited. Here, we simulate a region of lymphoid tissue using a cellular Potts model to characterize the functional response of CTL killing of target cells, and find that the total killing rate saturates both with the CTL and the target cell densities. The relative saturation in CTL and target cell densities is determined by whether a CTL can kill multiple target cells at the same time, and whether a target cell can be killed by many CTLs together. We find that all the studied regimes can be well described by a double-saturation (DS) function with two different saturation constants. We show that this DS model can be mechanistically derived for the cases where target cells are killed by a single CTL. For the other cases, a biological interpretation of the parameters is still possible. Our results imply that this DS function can be used as a tool to predict the cellular interactions in cytotoxicity data. PMID:24739177

  20. Tissue Dimensionality Influences the Functional Response of Cytotoxic T Lymphocyte-Mediated Killing of Targets.

    PubMed

    Gadhamsetty, Saikrishna; Marée, Athanasius F M; de Boer, Rob J; Beltman, Joost B

    2016-01-01

    Cytotoxic T lymphocyte (CTL)-mediated killing of virus infections and tumors occurs over a wide range of conditions. The spatial environments in which CTLs encounter target cells vary from narrow vessels, to two-dimensional epithelial tissues, to densely populated 3-dimensional (3D) T cell areas within lymphoid tissues. How such spatial environments alter the functional response of CTL-mediated killing, i.e., how the killing efficiency depends on cell densities, is unclear. In this study, we perform cellular Potts model simulations in different spatial configurations to investigate how the dimensionality of the space affects the functional response of CTL-mediated killing. Irrespective of the spatial configuration, the function with separate saturation constants for CTL and for target cell densities that we previously proposed can in all cases describe the response, demonstrating its generality. However, the tissue dimensionality determines at which cell densities the killing rate starts to saturate. We show that saturation in a fully 3D environment is stronger than in a "flat" 3D environment, which is largely due to accompanying differences in the CTL-target encounter rates.

  1. A general functional response of cytotoxic T lymphocyte-mediated killing of target cells.

    PubMed

    Gadhamsetty, Saikrishna; Marée, Athanasius F M; Beltman, Joost B; de Boer, Rob J

    2014-04-15

    Cytotoxic T lymphocytes (CTLs) kill virus-infected cells and tumor cells, and play a critical role in immune protection. Our knowledge of how the CTL killing efficiency varies with CTL and target cell numbers is limited. Here, we simulate a region of lymphoid tissue using a cellular Potts model to characterize the functional response of CTL killing of target cells, and find that the total killing rate saturates both with the CTL and the target cell densities. The relative saturation in CTL and target cell densities is determined by whether a CTL can kill multiple target cells at the same time, and whether a target cell can be killed by many CTLs together. We find that all the studied regimes can be well described by a double-saturation (DS) function with two different saturation constants. We show that this DS model can be mechanistically derived for the cases where target cells are killed by a single CTL. For the other cases, a biological interpretation of the parameters is still possible. Our results imply that this DS function can be used as a tool to predict the cellular interactions in cytotoxicity data.

  2. Induction of cytotoxic T-lymphocytes by electroporation-enhanced needle-free skin immunization.

    PubMed

    Zhao, Y L; Murthy, S N; Manjili, M H; Guan, L J; Sen, A; Hui, S W

    2006-02-27

    A needle-free method based on transcutaneous electroporation is described for delivering peptide vaccines. The K(b)-binding OVA-peptide SIINFEKL was used as an example to induce the peptide-specific cytotoxic T-lymphocytes (CTL) response in mice. A saturated anionic lipid was added during electroporation, and post-pulse electro-osmosis was applied to enhance the vaccine delivery. Electroporation was found to stimulate the exodus of Langerhans cells (LC) from the skin. The peptide transported into and through murine skin was measured using a Franz diffusion apparatus. Most peptide was retained in the skin rather than passing through the skin in the process. The peptide was delivered to the dorsal skin of mice by in vivo electroporation. An electroporation-transportable oligonucleotide with CpG motif was used as adjuvant. The efficacy of peptide delivery was comparable to that of intradermally injected with Freund's complete adjuvant (FCA). Peptide-specific CTL response to the vaccine delivered by needle-free electroporation/electro-osmosis was equivalent to that delivered by intradermal injection, as determined by production of the peptide-specific IFN-gamma in ELISPOT assay.

  3. Effects of Clostridium difficile Toxin A and B on Human T Lymphocyte Migration

    PubMed Central

    Wu, Dan; Joyee, Antony George; Nandagopal, Saravanan; Lopez, Marianela; Ma, Xiuli; Berry, Jody; Lin, Francis

    2013-01-01

    Bacterial products such as toxins can interfere with a variety of cellular processes, leading to severe human diseases. Clostridium difficile toxins, TcdA and TcdB are the primary contributing factors to the pathogenesis of C. difficile-associated diseases (CDAD). While the mechanisms for TcdA and TcdB mediated cellular responses are complex, it has been shown that these toxins can alter chemotactic responses of neutrophils and intestinal epithelial cells leading to innate immune responses and tissue damages. The effects of C. difficile toxins on the migration and trafficking of other leukocyte subsets, such as T lymphocytes, are not clear and may have potential implications for adaptive immunity. We investigated here the direct and indirect effects of TcdA and TcdB on the migration of human blood T cells using conventional cell migration assays and microfluidic devices. It has been found that, although both toxins decrease T cell motility, only TcdA but not TcdB decreases T cell chemotaxis. Similar effects are observed in T cell migration toward the TcdA- or TcdB-treated human epithelial cells. Our study demonstrated the primary role of TcdA (compared to TcdB) in altering T cell migration and chemotaxis, suggesting possible implications for C. difficile toxin mediated adaptive immune responses in CDAD. PMID:23645153

  4. Functional changes in astrocytes by human T-lymphotropic virus type-1 T-lymphocytes.

    PubMed

    Akaoka, H; Szymocha, R; Beurton-Marduel, P; Bernard, A; Belin, M F; Giraudon, P

    2001-10-30

    The human T-lymphotropic virus type-1 (HTLV-1) is the causative agent of a chronic progressive myelopathy (TSP/HAM) in which lesions of the central nervous system (CNS) are associated with infiltration of HTLV-1-infected T-cells. In a model that mimics the interaction between glial and T-cells, we show that transient contact with T-lymphocytes chronically infected with HTLV-1 induce profound metabolic alterations in astrocytes. Within the first week post-contact, an overall activation of astrocyte metabolism was observed as assessed by enhanced uptake of glutamate and glucose, and lactate release. In contrast, longer examination showed a reduced astrocytic accumulation of glutamate. The time course of the change in glutamate uptake was in fact biphasic. Previous observations indicated that HTLV-1 protein Tax-1 was involved in this delayed decrease, via the induction of TNF-alpha. The expression of the glial glutamate transporters, GLAST and GLT-1 decreased in parallel. These decreases in glutamate uptake and transporters' expression were associated with an imbalance in the expression of the catabolic enzymes of glutamate, GS and GDH, presumably due to Tax-1. Given the fact that impairment of glutamate management in astrocytes is able to compromise the functional integrity of neurons and oligodendrocytes, our results altogether give new insights into the physiopathology of TSP/HAM.

  5. Effects of anti-human T lymphocyte immune globulins in patients: new or old.

    PubMed

    Wang, Diane C; Wang, Xiangdong; Chen, Chengshui

    2016-09-01

    Multiple studies demonstrated that anti-human T lymphocyte immune globulins (ATG) can decrease the incidence of acute and chronic graft rejection in cell or organ transplants. However, further in-depth study indicates that different subgroups may benefit from either different regimes or alteration of them. Studies among renal transplant patients indicate that low immunological risk patients may not gain the same amount of benefit and thus tilt the risk versus benefit consideration. This may hold true for low immunological risk patients receiving other organ transplants and would be worth further investigation. The recovery time of T cells and natural killer (NK) cells also bears consideration and the impact that it has on the severity and incidence of opportunistic infections closely correlated with the dosage of ATG. The use of lower doses of ATG in combination with other induction medications may offer a solution. The finding that ATG may lose efficacy in cases of multiple transplants or re-transplants in the case of heart transplants may hold true for other transplantations. This may lead to reconsideration of which induction therapies would be most beneficial in the clinical setting. These studies on ATG done on different patient groups will naturally not be applicable to all, but the evidence accrued from them as a whole may offer us new and different perspectives on how to approach and potentially solve the clinical question of how to best reduce the mortality associated with chronic host-versus-graft disease.

  6. Reduced frequency of T lymphocytes expressing CTLA-4 in frontotemporal dementia compared to Alzheimer's disease.

    PubMed

    Santos, Rodrigo Ribeiro; Torres, Karen C; Lima, Giselle S; Fiamoncini, Carolina M; Mapa, Filipe C; Pereira, Patricia A; Rezende, Vitor B; Martins, Luiza C; Bicalho, Maria A; Moraes, Edgar N; Reis, Helton J; Teixeira, Antonio L; Romano-Silva, Marco A

    2014-01-03

    Studies suggest that inflammation is involved in the neurodegenerative cascade of dementias. Immunological mechanisms may be part of the pathophysiological process in frontotemporal dementia (FTD), but up till now only vague evidence of such mechanisms has been presented. The B7- CD28/CTLA-4 pathway is an important immunological signaling pathway involved in modulation of T cell activation. The aim of this study was to compare the expression of molecules associated with co-stimulatory signaling in peripheral blood mononuclear cells (PBMC) of FTD to Alzheimer disease (AD) and control groups. Our results confirm the previous demonstrated increased expression of CD80 in CD14+ Alzheimer patients T cells but show, for the first time, a reduction in the expression of CTLA-4 in CD4+ FTD cells. As CTLA-4 is the most potent negative regulators of T-cell activation we speculated that peripheral T lymphocytes in FTD are more activated and this could be involved in the neurodegeneration observed in this dementia.

  7. Early T cell signalling is reversibly altered in PD-1+ T lymphocytes infiltrating human tumors.

    PubMed

    Wang, Shu-Fang; Fouquet, Stéphane; Chapon, Maxime; Salmon, Hélène; Regnier, Fabienne; Labroquère, Karine; Badoual, Cécile; Damotte, Diane; Validire, Pierre; Maubec, Eve; Delongchamps, Nicolas B; Cazes, Aurélie; Gibault, Laure; Garcette, Marylène; Dieu-Nosjean, Marie-Caroline; Zerbib, Marc; Avril, Marie-Françoise; Prévost-Blondel, Armelle; Randriamampita, Clotilde; Trautmann, Alain; Bercovici, Nadège

    2011-03-07

    To improve cancer immunotherapy, a better understanding of the weak efficiency of tumor-infiltrating T lymphocytes (TIL) is necessary. We have analyzed the functional state of human TIL immediately after resection of three types of tumors (NSCLC, melanoma and RCC). Several signalling pathways (calcium, phosphorylation of ERK and Akt) and cytokine secretion are affected to different extents in TIL, and show a partial spontaneous recovery within a few hours in culture. The global result is an anergy that is quite distinct from clonal anergy induced in vitro, and closer to adaptive tolerance in mice. PD-1 (programmed death -1) is systematically expressed by TIL and may contribute to their anergy by its mere expression, and not only when it interacts with its ligands PD-L1 or PD-L2, which are not expressed by every tumor. Indeed, the TCR-induced calcium and ERK responses were reduced in peripheral blood T cells transfected with PD-1. Inhibition by sodium stibogluconate of the SHP-1 and SHP-2 phosphatases that associate with several inhibitory receptors including PD-1, relieves part of the anergy apparent in TIL or in PD-1-transfected T cells. This work highlights some of the molecular modifications contributing to functional defects of human TIL.

  8. The effects of ILLLI on peripheral blood T lymphocytes subpopulation & NK cells in psoriasis treatment

    NASA Astrophysics Data System (ADS)

    Zhu, Jing; Nie, Fan

    2005-07-01

    Objective: To research the effects of Intravascular low level laser irradiation (ILLLI) on the immulogic function of cells in treatment of psoriasis. Method: 49 patients suffered from psoriasis were treated by Intravascular low level laser irradiation (laser output power: 4-5mw, 1 hour per day, a course of treatment is 10 days). We checked the function of T lymphocyte subgroup and NK cell in peripheral blood between pre and post treatment. Results: 1.The mean value of CD3+ in post treatment is higher. P<0.05. Significant difference is showed between pre and post treatment 2. The mean value of CD4+ in post treatment dropped slightly while the mean value of CD4/CD8, NK cell in post treatment increased little, nearly approach the mean value of natural person. 3.The mean value of CD4+,CD8+,NK cell which is under 30% increased the percent obviously after the treatment; The mean value of CD4+,CD8+ u higher than 30% obviously drop the percent, P#0.05 and <0.01. Related statistical analysis showed significant and much significant difference between pre and post treatment. Conclusions: The low level laser irradiation (ILLLI) in treatment of psoriasis has bidirectional ajustive effect which can balance the immulogic function of cell.

  9. HDAC6 regulates the dynamics of lytic granules in cytotoxic T lymphocytes

    PubMed Central

    Núñez-Andrade, Norman; Iborra, Salvador; Trullo, Antonio; Moreno-Gonzalo, Olga; Calvo, Enrique; Catalán, Elena; Menasche, Gaël; Sancho, David; Vázquez, Jesús; Yao, Tso-Pang

    2016-01-01

    HDAC6 is a tubulin deacetylase involved in many cellular functions related to cytoskeleton dynamics including cell migration and autophagy. In addition, HDAC6 affects antigen-dependent CD4+ T cell activation. In this study, we show that HDAC6 contributes to the cytotoxic function of CD8+ T cells. Immunization studies revealed defective cytotoxic activity in vivo in the absence of HDAC6. Adoptive transfer of wild-type or Hdac6-/- CD8+ T cells to Rag1-/- mice demonstrated specific impairment in CD8+ T cell responses against vaccinia infection. Mechanistically, HDAC6-deficient cytotoxic T lymphocytes (CTLs) showed defective in vitro cytolytic activity related to altered dynamics of lytic granules, inhibited kinesin 1 – dynactin mediated terminal transport of lytic granules to the immune synapse and deficient exocytosis, but not to target cell recognition, T cell receptor (TCR) activation or interferon (IFNγ) production. Our results establish HDAC6 as an effector of the immune cytotoxic response that acts by affecting the dynamics, transport and secretion of lytic granules by CTLs. PMID:26869226

  10. Dynamin2 controls Rap1 activation and integrin clustering in human T lymphocyte adhesion

    PubMed Central

    Eppler, Felix J.

    2017-01-01

    Leukocyte trafficking is crucial to facilitate efficient immune responses. Here, we report that the large GTPase dynamin2, which is generally considered to have a key role in endocytosis and membrane remodeling, is an essential regulator of integrin-dependent human T lymphocyte adhesion and migration. Chemical inhibition or knockdown of dynamin2 expression significantly reduced integrin-dependent T cell adhesion in vitro. This phenotype was not observed when T cells were treated with various chemical inhibitors which abrogate endocytosis or actin polymerization. We furthermore detected dynamin2 in signaling complexes and propose that it controls T cell adhesion via FAK/Pyk2- and RapGEF1-mediated Rap1 activation. In addition, the dynamin2 inhibitor-induced reduction of lymphocyte adhesion can be rescued by Rap1a overexpression. We demonstrate that the dynamin2 effect on T cell adhesion does not involve integrin affinity regulation but instead relies on its ability to modulate integrin valency. Taken together, we suggest a previously unidentified role of dynamin2 in the regulation of integrin-mediated lymphocyte adhesion via a Rap1 signaling pathway. PMID:28273099

  11. Heterologous expression of specific K+ channels in T lymphocytes: functional consequences for volume regulation.

    PubMed Central

    Deutsch, C; Chen, L Q

    1993-01-01

    It has been postulated that the K+ channel isoform Kv1.3 plays a role in regulatory volume decrease (RVD) in response to hypotonic shock. We show that a mouse cytotoxic T-lymphocyte line, CTLL-2, is devoid of voltage-dependent K+ channels and is unable to volume regulate. Transient transfection of these cells with Kv1.3 reconstitutes their ability to volume regulate. As predicted by our model, this ability depends critically on volume-induced changes in membrane potential and the isoform of the K+ channel used. When the cells were transfected with Kv3.1, an isoform believed to be expressed in a specific subclass of mouse thymocytes, the CTLL-2 cells did not show RVD. The difference in the ability of the two isoforms to confer the capacity for RVD is expected from differences in the voltage dependence of activation of the channels, according to our proposed model for RVD. The experimental approach that we use, transient transfection and panning to select positive transfectants, is highly effective; it has a > 95% efficiency. This method, and this cell line, may be important tools in studying lymphocyte K+ channels and their function in situ. Images Fig. 3 PMID:8234253

  12. Formin like 1 expression is increased on CD4+ T lymphocytes in spontaneous autoimmune uveitis.

    PubMed

    Degroote, Roxane L; Uhl, Patrizia B; Amann, Barbara; Krackhardt, Angela M; Ueffing, Marius; Hauck, Stefanie M; Deeg, Cornelia A

    2017-02-10

    The membrane protein expression repertoire of cells changes in course of activation. In equine recurrent uveitis (ERU), a spontaneous autoimmune disease in horses with relapsing and ultimately blinding inner eye inflammation, CD4+ T lymphocytes are the crucial pathogenic cells activated in the periphery directly prior to an inflammatory episode. In order to find relevant changes in the membrane proteome associated to disease, we sorted CD4+ lymphocytes and compared protein abundance from the generated proteome datasets of both healthy horses and ERU cases. We detected formin like 1, a key player in actin dependent cellular processes such as phagocytosis, cell adhesion and cell migration, with significantly higher abundance in the CD4+ cell membrane proteome of horses with ERU. In transmigration experiments, we demonstrated higher migration rate of cells originating from diseased animals connecting formin like 1 to the migratory ability of cells. These findings are the first description of formin like 1 in association to processes involved in migration of inflammatory CD4+ T cells across the blood-retinal barrier in a spontaneous ocular autoimmune disease and suggest formin like 1 to play a role in the molecular mechanisms of ERU disease pathogenesis. Data are available via ProteomeXchange with identifier PXD005384.

  13. Low CD4/CD8 T lymphocyte ratio in acute myocardial infarction.

    PubMed Central

    Syrjälä, H; Surcel, H M; Ilonen, J

    1991-01-01

    T lymphocyte subsets were analysed using monoclonal antibodies and flow cytometry to determine whether myocardial infarction and cardiopulmonary resuscitation induce changes in these. Groups of 11 infarct patients and 10 patients with past cardiopulmonary resuscitation were compared with 11 age- and sex-matched controls and 12 sepsis patients. The differences in the CD4/CD8 ratios between the four groups were significant (F = 7.71, P = 0.001). The infarct patients had lower CD4/CD8 ratios (mean +/- s.d. 0.83 +/- 0.43) than the control (2.12 +/- 1.13; P = 0.001) or sepsis cases (1.76 +/- 1.05; P = 0.004), but their ratios did not differ from those of the resuscitation group (0.93 +/- 0.79, P = 0.84). The latter group also had lower ratios than the control (P = 0.003) and sepsis groups (P = 0.013). Most infarct patients had an on admission inverted CD4/CD8 ratio which usually returned to normal in the next 2 days. A permanently low CD4/CD8 ratio may be a poor sign prognostically after both myocardial infarction and resuscitation. PMID:1899632

  14. Polyomavirus DNA is damaged in target cells during cytotoxic T-lymphocyte-mediated killing

    SciTech Connect

    Sellins, K.S.; Cohen, J.J.

    1989-02-01

    Target cell DNA damage is an early event in cytotoxic T-lymphocyte (CTS)-mediated killing. It has been hypothesized that this DNA damage may serve as one mechanism of destroying viral genetic material inside infected cells. The authors directly examined the fate of viral DNA in target cells during CTL-mediated lysis. Polyomavirus DNA in transfected murine P815 mastocytoma targets was digested along with cellular DNA into oligonucleosome-sized fragments, although intact forms, possibly virion-associated DNA, were also present. In infected BALB/3T3 murine fibroblasts, which normally undergo single-stranded nicks when killed by CTL, polyomavirus DNA was converted to relaxed forms in the presence of CTL. These results suggest that the fate of the viral DNA depends on the stage of the viral life cycle and corresponds to the fate of the host cell DNA. Cleavage of the viral genome prior to assembly may thus be an important mechanism in specific antiviral immunity.

  15. VAMP8-dependent fusion of recycling endosomes with the plasma membrane facilitates T lymphocyte cytotoxicity

    PubMed Central

    Marshall, Misty R.; Pattu, Varsha; Halimani, Mahantappa; Maier-Peuschel, Monika; Müller, Martha-Lena; Becherer, Ute; Hong, Wanjin; Hoth, Markus; Tschernig, Thomas

    2015-01-01

    Cytotoxic T lymphocytes (CTLs) eliminate infected and neoplastic cells through directed release of cytotoxic granule contents. Although multiple SNARE proteins have been implicated in cytotoxic granule exocytosis, the role of vesicular SNARE proteins, i.e., vesicle-associated membrane proteins (VAMPs), remains enigmatic. VAMP8 was posited to represent the cytotoxic granule vesicular SNARE protein mediating exocytosis in mice. In primary human CTLs, however, VAMP8 colocalized with Rab11a-positive recycling endosomes. Upon stimulation, these endosomes rapidly trafficked to and fused with the plasma membrane, preceding fusion of cytotoxic granules. Knockdown of VAMP8 blocked both recycling endosome and cytotoxic granule fusion at immune synapses, without affecting activating signaling. Mechanistically, VAMP8-dependent recycling endosomes deposited syntaxin-11 at immune synapses, facilitating assembly of plasma membrane SNARE complexes for cytotoxic granule fusion. Hence, cytotoxic granule exocytosis is a sequential, multivesicle fusion process requiring VAMP8-mediated recycling endosome fusion before cytotoxic granule fusion. Our findings imply that secretory granule exocytosis pathways in other cell types may also be more complex than previously appreciated. PMID:26124288

  16. Retractile processes in T lymphocyte orientation on a stimulatory substrate: morphology and dynamics

    NASA Astrophysics Data System (ADS)

    Arkhipov, Sergey N.; Maly, Ivan V.

    2008-03-01

    T cells of the immune system target infected and tumor cells in crowded tissues with high precision by coming into direct contact with the intended target and orienting the intracellular Golgi apparatus and the associated organelles to the area of the cell-cell contact. The mechanism of this orientation remains largely unknown. To further elucidate it we used three-dimensional microscopy of living T cells presented with an artificial substrate mimicking the target cell surface. The data indicate that long, finger-like processes emanate from the T cell surface next to the intracellular Golgi apparatus. These processes come in contact with the substrate and retract. The retraction accompanies the reorientation of the T cell body which brings the Golgi apparatus closer to the stimulatory substrate. Numerical modeling indicates that considering the forces involved the retraction of a process attached with one end to the cell body near the Golgi apparatus and with the other end to the substrate can bring the Golgi apparatus to the substrate by moving the entire cell body. The dynamic scenarios that are predicted by the quantitative model explain features of the reorientation movements that we measured but could not explain previously. We propose that retraction of the surface processes is a force-generating mechanism contributing to the functional orientation of T lymphocytes.

  17. A High Throughput Phenotypic Screen of Cytotoxic T Lymphocyte Lytic Granule Exocytosis Reveals Candidate Immunosuppressants

    PubMed Central

    Zhao, Ziyan; Haynes, Mark K.; Ursu, Oleg; Edwards, Bruce S.; Sklar, Larry A.; Zweifach, Adam

    2015-01-01

    We screened the NIH’s Molecular Libraries Small Molecule Repository for inhibitors of cytotoxic T lymphocyte (CTL) lytic granule exocytosis by measuring binding of an antibody in the extracellular solution to a lysosomal membrane protein (LAMP-1) that is transferred to the plasma membrane by exocytosis. We used TALL-104 human leukemic CTLs stimulated with soluble chemicals. Using high-throughput cluster cytometry to screen 364202 compounds in 1536-well plate format, identifying 2404 initial hits. 161 were confirmed on retesting, and dose-response measurements were performed. 75 of those compounds were obtained, and 48 were confirmed active. Experiments were conducted to determine the molecular mechanism of action (MMOA) of the active compounds. Fifteen blocked increases in intracellular calcium >50%. Seven blocked phosphorylation of ERK by upstream MAP kinase kinases >50%. One completely blocked the activity of the calcium-dependent phosphatase calcineurin. None blocked ERK catalytic activity. Eight blocked more than one pathway. For eight compounds, we were unable to determine an MMOA. The activity of one of these compounds was confirmed from powder resupply. We conclude that a screen based on antibody binding to CTLs is a good means of identifying novel candidate immunosuppressants with either known or unknown MMOA. PMID:25381253

  18. Identification of genes and pathways associated with cytotoxic T lymphocyte infiltration of serous ovarian cancer

    PubMed Central

    Leffers, N; Fehrmann, R S N; Gooden, M J M; Schulze, U R J; ten Hoor, K A; Hollema, H; Boezen, H M; Daemen, T; de Jong, S; Nijman, H W; van der Zee, A G J

    2010-01-01

    Background: Tumour-infiltrating lymphocytes (TILs) are predictors of disease-specific survival (DSS) in ovarian cancer. It is largely unknown what factors contribute to lymphocyte recruitment. Our aim was to evaluate genes and pathways contributing to infiltration of cytotoxic T lymphocytes (CTLs) in advanced-stage serous ovarian cancer. Methods: For this study global gene expression was compared between low TIL (n=25) and high TIL tumours (n=24). The differences in gene expression were evaluated using parametric T-testing. Selectively enriched biological pathways were identified with gene set enrichment analysis. Prognostic influence was validated in 157 late-stage serous ovarian cancer patients. Using immunohistochemistry, association of selected genes from identified pathways with CTL was validated. Results: The presence of CTL was associated with 320 genes and 23 pathways (P<0.05). In addition, 54 genes and 8 pathways were also associated with DSS in our validation cohort. Immunohistochemical evaluation showed strong correlations between MHC class I and II membrane expression, parts of the antigen processing and presentation pathway, and CTL recruitment. Conclusion: Gene expression profiling and pathway analyses are valuable tools to obtain more understanding of tumour characteristics influencing lymphocyte recruitment in advanced-stage serous ovarian cancer. Identified genes and pathways need to be further investigated for suitability as therapeutic targets. PMID:20664601

  19. Changes of B and T lymphocytes and selected apopotosis markers in Hashimoto's thyroiditis.

    PubMed

    Kaczmarek, Elzbieta; Lacka, Katarzyna; Jarmolowska-Jurczyszyn, Donata; Sidor, Anna; Majewski, Przemyslaw

    2011-07-01

    The aim was to assess changes of B and T lymphocytes and selected apoptotic markers in Hashimoto thyroiditis (HT) cases on the basis of quantitative immunohistochemical studies (CD20, CD43, CD8, Bcl-2, caspase-3). The control group comprised colloid goitres without inflammatory infiltrate taken from 10 female patients. Thyroid specimens were obtained retrospectively from 40 patients. The immunohistochemical reactions were subject to quantitative evaluation performed using image-processing methods, including a spatial visualisation of the markers' expression. The percentage of Bcl-2 reactions in HT (mean 3.65%, SD 2.94%) was significantly lower than in the control group (mean 13.99%, SD 5.04%), while the thyroid follicles in HT samples exhibited a higher degree of staining for caspase-3 (mean 1.10%, SD 1.03%) in contrast to normal control tissues (mean 0.48%, SD 1.02%). The results from this study indicate that apoptosis plays a major role in the patogenesis of autoimmune thyroid diseases containing the main pathogenic events in the lesion of thyroid follicular cells in HT. Moreover, the reactivity of CD43 and CD20 was significantly higher in Hashimoto disease, while CD8 was not significantly different from the control group.

  20. Engineered cytotoxic T lymphocytes with AFP-specific TCR gene for adoptive immunotherapy in hepatocellular carcinoma.

    PubMed

    Sun, Longhao; Guo, Hao; Jiang, Ruoyu; Lu, Li; Liu, Tong; He, Xianghui

    2016-01-01

    Alpha-fetoprotein (AFP) is overexpressed in hepatocellular carcinoma (HCC) and could serve as a tumor-associated antigen (TAA) and potential target for adoptive immunotherapy. However, low frequency and severe functional impairment of AFP-specific T cells in vivo hamper adoptive infusion. TAA-specific T cell receptor (TCR) gene transfer could be an efficient and reliable alternation to generate AFP-specific cytotoxic T lymphocytes (CTLs). Autologous dendritic cells (DC) pulsed with AFP158-166 peptides were used to stimulate AFP-specific CTLs. TCR α/β chain genes of AFP-specific CTLs were cloned and linked by 2A peptide to form full-length TCR coding sequence synthesized into a lentiviral vector. Nonspecific activated T cells were engineered by lentivirus infection. Transgenetic CTLs were evaluated for transfection efficiency, expression of AFP158-166-specific TCR, interferon (IFN)-γ secretion, and specific cytotoxicity toward AFP+ HCC cells in vitro and in vivo. Flow cytometry revealed the AFP158-166-MHC-Pentamer positive transgenetic CTLs was 9.86 %. The number of IFN-γ secretion T cells and the specific cytotoxicity toward HpeG2 in vitro and in tumor-bearing NOD/SCID mice were significantly raised in transgenetic CTLs than that of AFP158-166-specific CTLs obtained by peptide-pulsed DCs or control group. TCR gene transfer is a promising strategy to generate AFP158-166-specific CTLs for the treatment of HCC.

  1. Effect of melatonin on monochromatic light-induced T-lymphocyte proliferation in the thymus of chickens.

    PubMed

    Chen, Fuju; Reheman, Aikebaier; Cao, Jing; Wang, Zixu; Dong, Yulan; Zhang, Yuxian; Chen, Yaoxing

    2016-08-01

    A total of 360 post-hatching day 0 (P0) Arbor Acre male broilers, including intact, sham operation and pinealectomy groups, were exposed to white light (WL), red light (RL), green light (GL) and blue light (BL) from a light-emitting diode (LED) system until for P14. We studied the effects of melatonin and its receptors on monochromatic light-induced T-lymphocyte proliferation in the thymus of broilers. The density of proliferating cell nuclear antigen (PCNA) cells and the proliferation of T-lymphocytes in response to Concanavalin A (ConA) in GL significantly increased both in vivo and in vitro (from 9.57% to 32.03% and from 34.30% to 50.53%, respectively) compared with other lights (p<0.005) and was strongly correlated with melatonin levels in plasma (p<0.005). Pinealectomy reduced the levels of circulatory melatonin and the proliferation of T-lymphocytes and eliminated the differences between GL and other lights (p<0.005). However, exogenous melatonin (10(-9)M) significantly increased the proliferative activity of T-lymphocyte by 9.64% (p=0.002). In addition, GL significantly increased mRNA expression levels of Mel1a, Mel1b and Mel1c receptors from 21.09% to 32.57%, and protein expression levels from 24.43% to 42.92% compared with RL (p<0.05). However, these effects were blocked after pinealectomy. Furthermore, 4P-PDOT (a selective Mel1b antagonist) and prazosin (a selective Mel1c antagonist) attenuated GL-induced T-lymphocyte proliferation in response to ConA (p=0.000). Luzindole (a nonselective Mel1a/Mel1b antagonist), however, did not induce these effects (p=0.334). These results suggest that melatonin may mediate GL-induced T-lymphocyte proliferation via the Mel1b and Mel1c receptors but not via the Mel1a receptor.

  2. Induction of Bcl-xL-specific cytotoxic T lymphocytes in mice.

    PubMed

    Larsen, H L; Andersen, M H; Wandall, H H; Madsen, C B; Christensen, R E; Petersen, T R; Pedersen, A E

    2014-08-01

    The induction of active immunity against tumour-associated antigens to prevent relapse of cancer is a promising approach but has so far shown only low efficacy. This low efficacy may in part be due to clonal escape of tumour cell variants by the downregulation of antigen expression or inflammation-induced dedifferentiation. Identification of novel tumour-associated antigens that at the same time are essential for continued tumour cell survival is thus critical for the development of active cancer vaccinations. At the same time, identification of novel endogenous murine tumour antigens will help improve preclinical development of cancer immunotherapy. The anti-apoptotic protein Bcl-xL has been suggested to be such an essential tumour antigen, but the lack of well-defined murine epitopes have delayed preclinical studies of Bcl-xL-targeting cancer vaccines. Here, we report the identification of two novel murine tumour-associated epitopes TAYQSFEQV and AFFSFGGAL derived from mouse Bcl-xL. Dendritic cell (DC)-based vaccination induced CD8(+) T cells capable of producing IFN-γ upon restimulation with these epitopes. Thus, our data may benefit the design of future immunotherapy strategies by providing a preclinical model for cancer vaccination with an endogenous tumour antigen that can be combined with other cancer treatments.

  3. In vitro and ex vivo evaluation of a multi-epitope heparinase vaccine for various malignancies.

    PubMed

    Tang, Xu-Dong; Guo, Shu-Liang; Wang, Guo-Zhen; Li, Ning; Wu, Yu-Yun; Fang, Dian-Chun; Fan, Ya-Han; Yang, Shi-Ming

    2014-01-01

    Previous studies have indicated that heparanase (Hpa) might represent a candidate universal tumor-associated antigen. However, vaccine therapy targeting only one cytotoxic T lymphocyte (CTL) epitope is suboptimal in preventing cancer. In the present study, we designed heparanase multi-epitope vaccines to increase the immune response to standard single heparanase epitopes. The results showed that multi-epitope vaccines Hpa525 + 277 + 405 + 16 and Hpa8 + 310 + 315 + 363 induced higher Hpa-specific lysis of various cancer cells from different tissues in a HLA-A2-restricted and heparanase-specific manner compared with the single epitope vaccines Hpa525, Hpa277, Hpa405, Hpa16, Hpa8, Hpa310, Hpa315 and Hpa363, both in vitro and ex vivo. Heparanase multi-epitope vaccines not only induced the heparanase-specific CTL to lyse tumor cells but also increased CTL secretion of interferon-γ. However, these heparanase-specific CTL did not lyse heparanase-expressing autologous lymphocytes and dendritic cells, which confirms the safety of these multi-epitope vaccines. Therefore, the present study provides theoretical evidence for the use of heparanase multi-epitope vaccines for clinical application.

  4. Cytotoxic-T-lymphocyte-mediated elimination of target cells transduced with engineered adeno-associated virus type 2 vector in vivo.

    PubMed

    Li, Chengwen; Hirsch, Matt; DiPrimio, Nina; Asokan, Aravind; Goudy, Kevin; Tisch, Roland; Samulski, R Jude

    2009-07-01

    A recent clinical trial in patients with hemophilia B has suggested that adeno-associated virus (AAV) capsid-specific cytotoxic T lymphocytes (CTLs) eliminated AAV-transduced hepatocytes and resulted in therapeutic failure. AAV capsids elicit a CTL response in animal models; however, these capsid-specific CTLs fail to kill AAV-transduced target cells in mice. To better model the human clinical trial data in mice, we introduced an immunodominant epitope derived from ovalbumin (OVA; SIINFEKL) into the AAV capsid and tested CTL-mediated killing of AAV2-transduced target tissues in vivo. Initially, in vitro experiments demonstrated both classical class I and cross-presentation of the OVA antigen, following endogenous expression or AAV2-OVA vector transduction, respectively. Furthermore, an OVA-specific CTL response was elicited after muscular or systemic injection of the AAV2-OVA vector. Finally, CTL reactivity was enhanced in mice with established SIINFEKL-specific immunity after AAV2-OVA/alpha1 anti-trypsin (AAT) administration. Most importantly, these OVA-specific CTLs decreased AAT expression in mice treated with AAV2-OVA/AAT vector that followed a time course mimicking uncoating kinetics of AAV2 transduction in OVA-immunized mice. These results demonstrate that AAV capsid-derived antigens elicit CD8(+) CTL reactivity, and these CTLs eliminated AAV-transduced target cells in mice. Notably, this model system can be exploited to study the kinetics of capsid presentation from different serotypes of AAV and permit the design of novel strategies to block CTL-mediated killing of AAV-transduced cells.

  5. Cytotoxic-T-Lymphocyte-Mediated Elimination of Target Cells Transduced with Engineered Adeno-Associated Virus Type 2 Vector In Vivo▿

    PubMed Central

    Li, Chengwen; Hirsch, Matt; DiPrimio, Nina; Asokan, Aravind; Goudy, Kevin; Tisch, Roland; Samulski, R. Jude

    2009-01-01

    A recent clinical trial in patients with hemophilia B has suggested that adeno-associated virus (AAV) capsid-specific cytotoxic T lymphocytes (CTLs) eliminated AAV-transduced hepatocytes and resulted in therapeutic failure. AAV capsids elicit a CTL response in animal models; however, these capsid-specific CTLs fail to kill AAV-transduced target cells in mice. To better model the human clinical trial data in mice, we introduced an immunodominant epitope derived from ovalbumin (OVA; SIINFEKL) into the AAV capsid and tested CTL-mediated killing of AAV2-transduced target tissues in vivo. Initially, in vitro experiments demonstrated both classical class I and cross-presentation of the OVA antigen, following endogenous expression or AAV2-OVA vector transduction, respectively. Furthermore, an OVA-specific CTL response was elicited after muscular or systemic injection of the AAV2-OVA vector. Finally, CTL reactivity was enhanced in mice with established SIINFEKL-specific immunity after AAV2-OVA/α1 anti-trypsin (AAT) administration. Most importantly, these OVA-specific CTLs decreased AAT expression in mice treated with AAV2-OVA/AAT vector that followed a time course mimicking uncoating kinetics of AAV2 transduction in OVA-immunized mice. These results demonstrate that AAV capsid-derived antigens elicit CD8+ CTL reactivity, and these CTLs eliminated AAV-transduced target cells in mice. Notably, this model system can be exploited to study the kinetics of capsid presentation from different serotypes of AAV and permit the design of novel strategies to block CTL-mediated killing of AAV-transduced cells. PMID:19369348

  6. Inhibition of CD4+ T lymphocyte binding to fibronectin and immune-cell accumulation in inflammatory sites by non-peptidic mimetics of Arg-Gly-Asp.

    PubMed Central

    Hershkoviz, R; Greenspoon, N; Mekori, Y A; Hadari, R; Alon, R; Kapustina, G; Lider, O

    1994-01-01

    The Arg-Gly-Asp (RGD) cell adhesion motif has been demonstrated in various studies to play a pivotal role in leucocyte and platelet interactions with plasma and extracellular matrix (ECM) glycoproteins. The recognition of the RGD sequence is mediated by heterodimeric receptors designated integrins of the beta 1 subfamily, expressed on distinct cell types, including T lymphocytes. We have recently shown that flexible non-peptidic mimetics of RGD, in which the two ionic side groups were separated by a linear spacer of 11 atoms, bound specifically to the platelet integrin alpha 11b beta 3, and inhibited T cell-mediated immune responses. The present study was designed to (i) further characterize the structural requirements for RGD interactions with CD4+ T cells, and (ii) examine the mechanisms by which the RGD mimetics interfere with immune cell reactivity in vivo. We now report that freezing the conformational degrees of freedom in the spacer chain, which fixes the relative orientation of the guanidinium and carboxylate side groups in a favourable manner, results in a higher level of inhibition of T cell binding to immobilized fibronectin, an RGD-containing ECM glycoprotein. In vivo, treatment of mice with relatively low doses of the RGD mimetics, but not the RGD peptide, inhibited the elicitation of an adoptively transferred DTH reaction. This inhibition was achieved by direct impairment of the ability of antigen-primed lymph node cells to migrate and accumulate in inflammatory sites. Hence, we suggest that the design and production of non-peptidic mimetics of RGD offers a novel approach to study defined parameters related to the structure-function requirements of small adhesion epitopes. Furthermore, this approach could be used therapeutically to inhibit pathological processes which depend on RGD recognition. PMID:7905794

  7. Computer-based design of an HLA-haplotype and HIV-clade independent cytotoxic T-lymphocyte assay for monitoring HIV-specific immunity.

    PubMed Central

    Amicosante, Massimo; Gioia, Cristiana; Montesano, Carla; Casetti, Rita; Topino, Simone; D'Offizi, Gianpiero; Cappelli, Giulia; Ippolito, Giuseppe; Colizzi, Vittorio; Poccia, Fabrizio; Pucillo, Leopoldo P.

    2002-01-01

    BACKGROUND: Human immunodeficiency virus (HIV)- specific CD8-positive cytotoxic T-lymphocytes (CTL) play a key role in controlling HIV infection. Monitoring CTL response could be clinically relevant during structured therapy interruption (STI), HIV exposure, and vaccine trials. However, HLA patients' restriction and HIV variability limited the development of a CTL assay with broad specificity. MATERIALS AND METHODS: We designed an HLA-class I/HIV-1 clade independent assay for assessing HIV- specific CTL by using a computer-assisted selection ofthe CTL epitopes. Twenty-eight 15-mers were selected by peptide-binding motifs analysis using different databases (HIV-Immunology Database, SYFPEITHI, BIMAS). Altogether they putatively bind to more than 90% of HLA haplotypes in different populations, with an overall HIV-1 variability below 9%. The peptide pool was used as an antigen in an intracellular cytokine staining (ICS) assay for quantifying HIV-specific CTL response. RESULTS: The test can be performed using both fresh and cryopreserved peripheral blood mononuclear cells (PBMC), whereas GAG protein as antigen works only on fresh PBMC. A significantly higher CTL response with respect to HIV-negative controls was detected in all HIV-1 infected subjects of two groups of patients with different ethnicities (Caucasians and Africans) and coming from areas with different HIV-1 clade prevalences (clade B and A/G, respectively). In Caucasian patients, after month of STI, the number of HIV-1 specific CTL (2,896 +/- 2,780 IFN-gamma specific CD8 cells/ml) was significantly higher than that found at enrolment (2,125 +/- 4,426 IFN-gamma specific CD8 cells/ml, p< 0.05). CONCLUSIONS: These data indicate that this CTL assay is broadly specific and could represent a useful clinical tool for HIV immunodiagnostic independent of HLA-haplotype and HIV-clade variabilities. PMID:12606814

  8. High-affinity interactions between peptides and heat shock protein 70 augment CD8+ T lymphocyte immune responses.

    PubMed

    Flechtner, Jessica B; Cohane, Kenya Prince; Mehta, Sunil; Slusarewicz, Paul; Leonard, Alexis Kays; Barber, Brian H; Levey, Daniel L; Andjelic, Sofija

    2006-07-15

    Exogenously delivered antigenic peptides complexed to heat shock proteins (HSPs) are able to enter the endogenous Ag-processing pathway and prime CD8+ CTL. It was determined previously that a hybrid peptide containing a MHC class I-binding epitope and HSP70-binding sequence Javelin (J0) in complex with HSP70 could induce cytotoxic T cell responses in vivo that were more robust than those induced by the minimal epitope complexed with HSP70. The present study introduces a novel, higher-affinity HSP70-binding sequence (J1) that significantly enhances binding of various antigenic peptides to HSP70. A competition binding assay revealed a dissociation constant that was 15-fold lower for the H2-K(b) OVA epitope SIINFEKL-J1 compared with SIINFEKL-J0, indicating a substantially higher affinity for HSP70. Further, modifying the orientation of the hybrid epitope and introducing a cleavable linker sequence between the Javelin and the epitope results in even greater immunogenicity, presumably by greater efficiency of epitope processing. The enhanced immunogenicity associated with Javelin J1 and the cleavable linker is consistently observed with multiple mouse and human epitopes. Thus, by creating a series of epitopes with uniform, high-affinity binding to HSP70, successful multiple epitope immunizations are possible, with equal delivery of each antigenic epitope to the immune system via HSP70. These modified epitopes have the potential for creating successful multivalent vaccines for immunotherapy of both infectious disease and cancer.

  9. Cytolytic T lymphocytes specific for tumors and infected cells from mice with a retrovirus-induced immunodeficiency syndrome.

    PubMed Central

    Erbe, J G; Green, K A; Crassi, K M; Morse, H C; Green, W R

    1992-01-01

    LP-BM5 retrovirus complex-infected C57BL/6 mice develop immunodeficiency, somewhat analogous to AIDS, termed murine AIDS (MAIDS). After secondary stimulation with syngeneic B-cell lymphomas from LP-BM5-infected mice, C57BL/6 mice produced vigorous CD8+ cytotoxic T lymphocytes specific for MAIDS-associated tumors. An anti-LP-BM5 specificity was suggested because spleen and lymph node cells from LP-BM5-infected mice served as target cells in competition assays, and cells from LP-BM5, but not ecotropic, virus-infected mice functioned as secondary in vitro stimulators to generate cytotoxic T lymphocytes to MAIDS tumors. PMID:1560546

  10. [Novel therapy for malignant lymphoma: adoptive immuno-gene therapy using chimeric antigen receptor(CAR)-expressing T lymphocytes].

    PubMed

    Ozawa, Keiya

    2014-03-01

    Adoptive T-cell therapy using chimeric antigen receptor (CAR) technology is a novel approach to cancer immuno-gene therapy. CARs are hybrid proteins consisting of target-antigen-specific single-chain antibody fragment fused to intracellular T-cell activation domains (CD28 or CD137/CD3 zeta receptor). CAR-expressing engineered T lymphocytes can directly recognize and kill tumor cells in an HLA independent manner. In the United States, promising results have been obtained in the clinical trials of adoptive immuno-gene therapy using CD19-CAR-T lymphocytes for the treatment of refractory B-cell malignancies, including chronic lymphocytic leukemia (CLL) and acute lymphoblastic leukemia (ALL). In this review article, CD19-CAR-T gene therapy for refractory B-cell non-Hodgkin lymphoma is discussed.

  11. Murine viable motheaten mutation reveals a gene critical to the development of both B and T lymphocytes

    SciTech Connect

    Sidman, C.L.; Marshall, J.D.; Allen, R.D. )

    1989-08-01

    In lethally irradiated normal mice reconstituted with both normal and autoimmune mutant viable moth-eaten (me{sup v}) bone marrow, the me{sup v}-derived B and T cells display aberrant behavior, while those derived from the normal bone marrow develop and function normally. The observed developmental abnormalities of me{sup v} B and T lymphocytes are therefore intrinsic to these cell types, rather than being determined by defective influences from the cells' environment. These data bring into question the in vivo significance of reported intracellular regulatory defects in motheaten (me) and me{sup v} mice and suggest that these mutations affect a gene whose product acts cell autonomously in the development of several hematopoietic cell lineages including B and T lymphocytes.

  12. Cytotoxic T Lymphocyte Antigen-4 Gene Variants in Type 2 Diabetic Patients with or without Neuropathy.

    PubMed

    Kiani, Javad; Khadempar, Saedeh; Hajilooi, Mehrdad; Rezaei, Hamzeh; Keshavarzi, Fatemeh; Solgi, Ghasem

    2016-06-01

    Many studies have shown that cytotoxic T lymphocyte antigen-4 (CTLA-4) gene variants are associated with several autoimmune diseases particularly type 1 diabetes. Due to the lack of consistent data for this association with type 2 diabetes (T2D), this study explored the possible influence of CTLA-4 gene polymorphisms at -1722 (T/C), -318 (C/T), and +49 (G/A) positions for susceptibility to T2D in relation with neuropathy. One hundred and eleven unrelated patients with T2D [49 patients with diabetic peripheral neuropathy (DPN) and 62 patients without PDN] and 100 healthy ethnic- and gender-matched controls were included in this study. The dimorphisms at -1722 (C/T), -318 (C/T) and +49 (A/G) for CTLA-4 gene were determined using ARMS-PCR. The CTLA-4 (+49 G/G) and (+49 A/A) genotypes were found to be positively and negatively associated with T2D, respectively (p=0.03). The -318 C/T and T/T genotypes were more frequent in patients than controls and -318 C/C genotype was shown to be protective for T2D (p=0.003). ACT and GTT Haplotypes were less and more frequent in controls and patients, respectively (p=3.86×10-7 and p=2.29×10-5). Genotypes distribution among T2D patients with and without DPN compared to healthy controls showed significantly lower frequencies for -318 C/C and +49 A/A genotypes and significantly higher frequencies for -318 C/T and T/T genotypes as well. Our findings indicate that CTLA-4 (+49 A/G) and (-318 C/T) genotypes could be considered as genetic risk factors associated with susceptibility or protection for T2D.

  13. Effect of prolactin on carcinoembryonic antigen-specific cytotoxic T lymphocyte response induced by dendritic cells.

    PubMed

    Matera, L; Beltramo, E; Martinuzzi, E; Buttiglieri, S

    2004-08-01

    The cytokine hormone prolactin (PRL) has been shown previously to modulate native cellular responses and maturation of antigen-presenting cells. Here we have addressed its effect on the antigen-specific response of cytotoxic T lymphocytes (CTL). CTL were generated from HLA-A2 lymphocytes after three rounds of stimulation with autologous dendritic cells loaded with HLA-A2-restricted carcinoembrionic antigen (CEA) Cap-1 (YLSGANLNL) peptide. Selected cultures were expanded on cytokine-supplemented feeder-layers, enriched for CD8+ lymphocytes and analysed for PRL-receptor (PRL-R) expression and PRL responsiveness. Resting CD8+ lymphocytes were negative for PRL-R, whereas antigen-activated CD8+ lymphocytes derived from long-term cultures were highly positive. Results of a 51Cr release assay showed CTL killing of CEA-loaded, but not unloaded, T2 cell line and the CEA-positive gastric carcinoma cell line KATO, but not of the CEA-negative T leukaemia cell line Jurkat. Interferon (IFN)-gamma release, evaluated in an ELISPOT assay against CEA-loaded T2, was enhanced (P < 0.05) by concentrations of PRL (12-25 ng/ml) very close to the physiological levels (6-20 ng/ml), but was decreased (P < 0.05) by high concentrations (200 ng/ml). Pre-incubation of the stimulators with the anti-MHC class I MoAb W6.32 induced a 40-60% decrease of the PRL-boosted IFN-gamma release, thus proving the MHC restriction of the lymphocyte response. Cytotoxicity against CEA-loaded T2 and KATO cell lines was also increased by 12-25 ng (P < 0.05) and decreased (P < 0.05) by 200 ng PRL. Pre-incubation of CTL with an antibody specific for the PRL-R almost completely abrogated this effect.

  14. Inhibition of murine splenic T lymphocyte proliferation by 2-deoxy-D-glucose-induced metabolic stress

    NASA Technical Reports Server (NTRS)

    Miller, E. S.; Klinger, J. C.; Akin, C.; Koebel, D. A.; Sonnenfeld, G.

    1994-01-01

    Female Swiss-Webster mice were injected with the glucose analogue 2-deoxy-D-glucose (2-DG), which when administered to rodents induces acute periods of metabolic stress. A single or multiple injections of 2-DG invoked a stress response, as evidenced by increases in serum corticosterone levels. The influence of this metabolic stressor on the blastogenic potential of splenic T lymphocytes was then examined. It was found that one, two, or three injections of 2-DG resulted in depressed T cell proliferative responses, with an attenuation of the effect occurring by the fifth injection. The 2-DG-induced inhibition of T cell proliferation was not attributable to 2-DG-induced cytolysis, as in vitro incubation of naive T cells with varying concentrations of 2-DG did not result in a reduction in cell number or viability, and flow cytometric analysis demonstrated that percentages of CD3, CD4, and CD8 splenic T cells were not altered as a result of 2-DG-induced stress. Incubating naive T cells in varying concentrations of 2-DG resulted in a dose-dependent inhibition of T cell blastogenic potential. Following in vivo exposure to 2-DG, T cell proliferation did not return to normal levels until 3 days after the cessation of 2-DG injections. Administering the beta-adrenergic receptor antagonist propranolol did not reverse the inhibited lymphoproliferation in 2-DG-treated mice. The inhibition in T cell proliferation was not observed, however, in mice that had been adrenalectomized or hypophysectomized and injected with 2-DG.(ABSTRACT TRUNCATED AT 250 WORDS).

  15. Transcriptional activation of the human cytotoxic serine protease gene CSP-B in T lymphocytes.

    PubMed Central

    Hanson, R D; Ley, T J

    1990-01-01

    The cytotoxic serine protease B (CSP-B) gene is activated during cytotoxic T-lymphocyte maturation. In this report, we demonstrate that the PEER T-cell line (bearing gamma/delta T-cell receptors) accumulates CSP-B mRNA following exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA) and N6-2'-O-dibutyryladenosine 3',5'-cyclic monophosphate (bt2cAMP) because of transcriptional activation of the CSP-B gene. TPA and bt2cAMP act synergistically to induce CSP-B expression, since neither agent alone causes activation of CSP-B transcription or mRNA accumulation. Chromatin upstream from the CSP-B gene is resistant to DNase I digestion in untreated PEER cells, but becomes sensitive following TPA-bt2cAMP treatment. Upon activation of PEER cells, a DNase I-hypersensitive site forms upstream from the CSP-B gene within a region that is highly conserved in the mouse. Transient transfection of CSP-B promoter constructs identified two regulatory regions in the CSP-B 5'-flanking sequence, located at positions -609 to -202 and positions -202 to -80. The region from -615 to -63 is sufficient to activate a heterologous promoter in activated PEER cells, but activation is orientation specific, suggesting that this region behaves as an upstream promoter element rather than a classical enhancer. Consensus AP-1, AP-2, and cAMP response elements are found upstream from the CSP-B gene (as are several T-cell-specific consensus elements), but the roles of these elements in CSP-B gene activation have yet to be determined. Images PMID:2233710

  16. Immunological potential of cytotoxic T lymphocyte antigen 4 immunoglobulin in murine autoimmune cholangitis.

    PubMed

    Tanaka, H; Yang, G-X; Tomiyama, T; Tsuneyama, K; Zhang, W; Leung, P S C; Coppel, R L; Joh, T; Nadler, S G; Ansari, A A; Bowlus, C; Gershwin, M E

    2015-06-01

    Cytotoxic T lymphocyte antigen 4 (CTLA-4) immunoglobulin (Ig) is an important regulator of T cell activation and a fusion protein directed at CD80 and CD86; it blocks co-stimulatory signalling and T cell activation. We have taken advantage of a murine model of human primary biliary cirrhosis (PBC), mice expressing a transforming growth factor (TGF)-β receptor II dominant negative (dnTGF-βRII) transgene to address the potential therapeutic efficacy of CTLA-4 Ig. To mimic patients with PBC at different stages or duration of disease, we treated mice with either CTLA-4 Ig or control IgG three times weekly from 3 to 12 or 24 weeks of age, or from 12 to 24 weeks of age. CTLA-4 Ig treatment from 3 weeks of age significantly reduced liver inflammation to 12 weeks of age. Treatment initiated at 12 weeks of age also ameliorated the autoimmune cholangitis at 24 weeks of age. However, in mice treated at 3 weeks of age, suppression of liver inflammation was not sustained and colitis was aggravated when treatment was extended to 24 weeks of age. Our data indicate that, in dnTGF-βRII mice, CTLA-4 Ig treatment has short-term beneficial effects on autoimmune cholangitis, but the effect varies according to duration of treatment and the time in which therapy was initiated. Further dissection of the events that lead to the reduction in therapeutic effectiveness of CTLA-4 Ig will be critical to determining whether such efforts can be applied to human PBC.

  17. Cytotoxic T lymphocyte-mediated cytolysis: an example of programmed cell death in the immune system

    SciTech Connect

    Duke, R.C.

    1985-01-01

    Target cells are programmed to die following interaction with cytotoxic T lymphocytes (CTLs). Within minutes of exposure to CTL the target cell's nuclear DNA is fragmented. Target cell lysis, as measured by /sup 51/Cr release, occurs about 60 minutes after induction of DNA fragmentation. DNA fragmentation results from the action of an endonuclease which cleaves DNA in the linker region between nucleosomes. The origin of this nuclease, whether transferred to the target by the CTL or endogenous to the target cell, has not been resolved. DNA fragmentation occurs only when appropriately sensitized CTL are used and is not merely the result of cell death because killing of target cells by extreme deviation from homeostasis, by interruption of energy production, or by lysis with antibody and complement does not induce DNA cleavage. When Triton X-100 is added to target cells which have interacted with CTL, the DNA fragments do not remain in association with the nucleus. This observation suggests that breakdown of overall nuclear structure is induced concomitantly with DNA fragmentation. Morphologically, disruption of nuclear structure and DNA fragmentation are observed as widespread chromatin condensation (apoptosis). Apoptosis is observed in metabolically active target cells and is not a consequence of cell death. A cell whose DNA is extensively fragmented is condemmed to die. Induction of oligonucleosome-sized DNA is also an early event in glucocorticoid-induced thymocyte death and death of T cells upon removal of growth factor. Several similarities exist between these systems and CTL-mediated cytolysis suggesting a final common biochemical pathway for all three types of cell death.

  18. Behavior and Properties of Mature Lytic Granules at the Immunological Synapse of Human Cytotoxic T Lymphocytes

    PubMed Central

    Ming, Min; Schirra, Claudia; Becherer, Ute; Stevens, David R.; Rettig, Jens

    2015-01-01

    Killing of virally infected cells or tumor cells by cytotoxic T lymphocytes requires targeting of lytic granules to the junction between the CTL and its target. We used whole-cell patch clamp to measure the cell capacitance at fixed intracellular [Ca2+] to study fusion of lytic granules in human CTLs. Expression of a fluorescently labeled human granzyme B construct allowed identification of lytic granule fusion using total internal reflection fluorescence microscopy. In this way capacitance steps due to lytic granule fusion were identified. Our goal was to determine the size of fusing lytic granules and to describe their behavior at the plasma membrane. On average, 5.02 ± 3.09 (mean ± s.d.) lytic granules were released per CTL. The amplitude of lytic granule fusion events was ~ 3.3 fF consistent with a diameter of about 325 nm. Fusion latency was biphasic with time constants of 15.9 and 106 seconds. The dwell time of fusing lytic granules was exponentially distributed with a mean dwell time of 28.5 seconds. Fusion ended in spite of the continued presence of granules at the immune synapse. The mobility of fusing granules at the membrane was indistinguishable from that of lytic granules which failed to fuse. While dwelling at the plasma membrane lytic granules exhibit mobility consistent with docking interspersed with short periods of greater mobility. The failure of lytic granules to fuse when visible in TIRF at the membrane may indicate that a membrane-confined reaction is rate limiting. PMID:26296096

  19. Interleukin-22 Is Produced by Invariant Natural Killer T Lymphocytes during Influenza A Virus Infection

    PubMed Central

    Paget, Christophe; Ivanov, Stoyan; Fontaine, Josette; Renneson, Joelle; Blanc, Fany; Pichavant, Muriel; Dumoutier, Laure; Ryffel, Bernhard; Renauld, Jean Christophe; Gosset, Philippe; Gosset, Pierre; Si-Tahar, Mustapha; Faveeuw, Christelle; Trottein, François

    2012-01-01

    Invariant natural killer T (iNKT) cells are non-conventional lipid-reactive αβ T lymphocytes that play a key role in host responses during viral infections, in particular through the swift production of cytokines. Their beneficial role during experimental influenza A virus (IAV) infection has recently been proposed, although the mechanisms involved remain elusive. Here we show that during in vivo IAV infection, mouse pulmonary iNKT cells produce IFN-γ and IL-22, a Th17-related cytokine critical in mucosal immunity. Although permissive to viral replication, IL-22 production by iNKT cells is not due to IAV infection per se of these cells but is indirectly mediated by IAV-infected dendritic cells (DCs). We show that activation of the viral RNA sensors TLR7 and RIG-I in DCs is important for triggering IL-22 secretion by iNKT cells, whereas the NOD-like receptors NOD2 and NLRP3 are dispensable. Invariant NKT cells respond to IL-1β and IL-23 provided by infected DCs independently of the CD1d molecule to release IL-22. In vitro, IL-22 protects IAV-infected airway epithelial cells against mortality but has no role on viral replication. Finally, during early IAV infection, IL-22 plays a positive role in the control of lung epithelial damages. Overall, IAV infection of DCs activates iNKT cells, providing a rapid source of IL-22 that might be beneficial to preserve the lung epithelium integrity. PMID:22294696

  20. Pseudomonas aeruginosa Exoenzyme S Is a Mitogen but Not a Superantigen for Human T Lymphocytes

    PubMed Central

    Bruno, Tony F.; Buser, Deborah E.; Syme, Rachel M.; Woods, Donald E.; Mody, Christopher H.

    1998-01-01

    Virtually all cystic fibrosis (CF) patients become infected with Pseudomonas aeruginosa, and once the infection is established, the organism is rarely cleared. One of the P. aeruginosa virulence factors, exoenzyme S, has been shown to correlate with increased morbidity and mortality both in rat models of chronic pulmonary inflammation and in human CF patients. It has previously been shown that exoenzyme S is a potent stimulus for the proliferation of T cells in greater than 95% of adults, which could contribute to the pathogenesis of CF. The goal of this study was to determine the mechanism of T-cell stimulation by exoenzyme S in an effort to shed light on the immune response and contribute to understanding its role in P. aeruginosa pathogenesis. The current studies demonstrate that exoenzyme S stimulates naive T cells, since fetal blood lymphocytes proliferated and adult lymphocytes that expressed CD45RA proliferated. The percentage of T cells activated by exoenzyme S after a 4-h culture (as measured by CD69 surface expression) was intermediate in magnitude compared to levels induced by a panel of superantigens and mitogens. To determine the mechanism of activation, the requirement for accessory cells was investigated. The proliferative response to exoenzyme S was dependent on the presence of accessory cells but was not blocked by an anti-DR antibody. Exoenzyme S activated both CD4+ and CD8+ T cells, but CD4+ T cells were preferentially activated. The Vβ repertoire of donor T cells showed no preferential activation or preferential expansion after stimulation by exoenzyme S, suggesting that it is not a superantigen. Taken together, our data suggest that exoenzyme S is a T-cell mitogen but not a superantigen. Activation of a large percentage of T lymphocytes by exoenzyme S may produce a lymphocyte-mediated inflammatory response that should be considered in the pathogenesis of CF. PMID:9632568

  1. In vitro generation of cytotoxic T lymphocyte response using dendritic cell immunotherapy in osteosarcoma

    PubMed Central

    He, Ye-Teng; Zhang, Qing-Min; Kou, Quan-Chun; Tang, Bo

    2016-01-01

    Immunotherapy with tumor lysate-pulsed dendritic cells (DCs) is one of the breakthrough strategies used in the treatment of cancer. However, DC-based immunotherapies for osteosarcoma are limited. In the present study, preclinical studies of a C3H osteosarcoma mouse model (produced by subcutaneous injection of LM8 murine osteosarcoma cells) validated the concept that LM8 cell lysate-pulsed bone marrow-derived DCs may evoke a more potent immune response compared with DCs that have been matured using polyinosinic:polycytidylic acid (poly I:C). A cytotoxic T lymphocyte (CTL) response was established using two groups of C3H mice (n=9) with osteosarcoma; the treatment group consisted of LM8 cell lysate-pulsed DCs and the control group consisted of DCs matured using poly I:C. Each group was immunized with doses of 1×106 cells twice per week for 3 weeks. No difference in the expression of cluster of differentiation markers was identified in the two groups. DCs pulsed with LM8 cell lysate were associated with the increased induction of CTL activity. Serum interferon-γ levels were increased in mice that received DCs pulsed with LM8 cell lysate compared with that in the poly I:C-matured DC group (P<0.041). Serum interleukin-4 was decreased in the treatment group vs. the control group (P<0.033). A mixed lymphocyte reaction assay confirmed that LM8-DC immunotherapy may evoke a significant antigen-specific immune response in a mouse model. The present study reveals promising data on efficacy of a DC-based immunotherapy in the treatment of osteosarcoma; however, further clinical studies are warranted. PMID:27446401

  2. T lymphocyte responses to antigens of gram-negative bacteria in pyelonephritis.

    PubMed

    Wilz, S W; Kurnick, J T; Pandolfi, F; Rubin, R H; Warren, H S; Goldstein, R; Kersten, C M; McCluskey, R T

    1993-10-01

    We showed previously that large numbers of T lymphocytes accumulate within a few days in the kidneys of rats with ascending pyelonephritis induced with Escherichia coli or Pseudomonas aeruginosa. CD4+ T cells propagated from the lesions exhibited MHC-restricted proliferative responses to formalin-fixed bacteria of the species used to induce infection. In the present study we investigated further the nature of the antigens responsible for the T cell proliferation and studied the ability of different bacterial strains and species to produce proliferative responses. We found that heat-killed bacteria were more stimulatory than formalin-fixed bacteria, and that soluble supernatants of heat-killed organism were also effective. The stimulatory effects of supernatants were destroyed by trypsin and the responses were MHC-restricted. Twelve different E. coli strains, with or without characteristics of uropathogenicity in humans, were all highly stimulatory to T cells derived from a kidney infected with a single E. coli strain. Strains of Klebsiella pneumoniae, Enterobacter aerogenes, and Serratia marcescens--species of Enterobacteriaceae closely related to E. coli--were also stimulatory, whereas more distantly related bacteria--Proteus, Morganella, and P. aeruginosa--were not. T cells propagated from kidneys infected with P. aeruginosa responded to supernatants of this organism, but not to E. coli supernatants. We conclude that a protein antigen (or antigens) shared by strains of E. coli and related Enterobacteriaceae, but not by other gram-negative bacteria, produce MHC-restricted proliferative responses of CD4+ T cells that infiltrate rat kidneys infected with E. coli.

  3. T-lymphocyte subpopulations in type I diabetes mellitus. A longitudinal study.

    PubMed

    Richens, E R; Jones, W G

    1985-01-01

    Monoclonal antibodies were used to characterize peripheral T-lymphocyte subpopulations in 23 patients with type I diabetes mellitus. Initial measurements were made at diagnosis and in 10 of the patients further studies were carried out at 1, 3 and 6 months. T-cell subsets were also measured in 16 patients with type II diabetes, in 16 patients with various autoimmune diseases and in 17 healthy control subjects. At diagnosis, the type I diabetic patients showed a significant decrease in the percentage of cytotoxic/suppressor cells. Both total T-cells and helper/inducer cells were normal. However, when the helper/inducer population was analyzed in the context of islet cell antibodies (ICAs), it was found that those patients possessing ICAs had significantly higher proportions of helper/inducer cells than those lacking them. A significant inverse correlation was seen between the proportions of total T-cells and NK/K cells. At 1 month, the proportions of cytotoxic/suppressor cells returned to normal, whilst the helper/inducer cells showed a transient depression. By 6 months, the only change seen was a significant increase in the percentage total t-cells. No relationship was found between T-cell subset perturbation and metabolic control, as assessed by measurement of hemoglobin A1 (HbA1). The type II diabetic patients showed a significant increase in the percentage of total T cells. The autoimmune patients also showed a significant increase in the proportions of total T-cells; this appeared to reflect an increase in the helper/inducer subset. In the autoimmune patients these findings occurred in conjunction with significant decreases in the absolute numbers of each T-cell subset. It is surmised that, in some cases of type I diabetes, alterations in immune homeostasis may permit autoimmune processes, which lead to cell damage at the onset of diabetes.

  4. CD3+CD8+CD28− T Lymphocytes in Patients with Lupus Nephritis

    PubMed Central

    Krajewska, Magdalena

    2016-01-01

    The results of studies on the CD3+CD8+CD28− cells in SLE are inconsistent since several analyses describe CD3+CD8+CD28− as either immunosuppressive or cytotoxic. The aim of this study is to inquire whether the quantitative changes of CD3+CD8+CD28− T lymphocytes subpopulation are related to the clinical status of patients with lupus nephritis. Evaluation of Foxp3 expression on CD3+CD8+CD28− cells may shed some light on functional properties of these cells. 54 adult SLE patients and 19 sex and age matched healthy volunteers were enrolled in the study. There were 15 patients in inactive (SLEDAI ≤ 5) and 39 in active (SLEDAI > 5) phase of disease. We determined absolute count of CD3+CD8+CD28− and CD3+CD8+CD28−Foxp3+ subpopulations by flow cytometry. We observed a statistically significant increase in absolute count and percentage of CD3+CD8+CD28− in SLE patients compared to HC (p < 0.001). Moreover there was significant positive correlation between increasing absolute count of CD3+CD8+CD28− cells and disease activity measured by SLEDAI (rs = 0.281, p = 0.038). Active LN patients had increased absolute count of CD3+CD8+CD28− cells compared to HC. Positive correlation of CD3+CD8+CD28− number with disease activity, and lack of Foxp3 expression on these cells, suggests that CD3+CD8+CD28− lymphocytes might be responsible for an increased proinflammatory response in the exacerbation of SLE. PMID:27446964

  5. Epithelial nuclear factor-κB signaling promotes lung carcinogenesis via recruitment of regulatory T lymphocytes.

    PubMed

    Zaynagetdinov, R; Stathopoulos, G T; Sherrill, T P; Cheng, D-S; McLoed, A G; Ausborn, J A; Polosukhin, V V; Connelly, L; Zhou, W; Fingleton, B; Peebles, R S; Prince, L S; Yull, F E; Blackwell, T S

    2012-06-28

    The mechanisms by which chronic inflammatory lung diseases, particularly chronic obstructive pulmonary disease, confer enhanced risk for lung cancer are not well-defined. To investigate whether nuclear factor (NF)-κB, a key mediator of immune and inflammatory responses, provides an interface between persistent lung inflammation and carcinogenesis, we utilized tetracycline-inducible transgenic mice expressing constitutively active IκB kinase β in airway epithelium (IKTA (IKKβ trans-activated) mice). Intraperitoneal injection of ethyl carbamate (urethane), or 3-methylcholanthrene (MCA) and butylated hydroxytoluene (BHT) was used to induce lung tumorigenesis. Doxycycline-treated IKTA mice developed chronic airway inflammation and markedly increased numbers of lung tumors in response to urethane, even when transgene expression (and therefore epithelial NF-κB activation) was begun after exposure to carcinogen. Studies using a separate tumor initiator/promoter model (MCA+BHT) indicated that NF-κB functions as an independent tumor promoter. Enhanced tumor formation in IKTA mice was preceded by increased proliferation and reduced apoptosis of alveolar epithelium, resulting in increased formation of premalignant lesions. Investigation of inflammatory cells in lungs of IKTA mice revealed a substantial increase in macrophages and lymphocytes, including functional CD4+/CD25+/FoxP3+ regulatory T lymphocytes (Tregs). Importantly, Treg depletion using repetitive injections of anti-CD25 antibodies limited excessive tumor formation in IKTA mice. At 6 weeks following urethane injection, antibody-mediated Treg depletion in IKTA mice reduced the number of premalignant lesions in the lungs in association with an increase in CD8 lymphocytes. Thus, persistent NF-κB signaling in airway epithelium facilitates carcinogenesis by sculpting the immune/inflammatory environment in the lungs.

  6. Expression of structurally diverse Qa-2-encoded molecules on the surface of cloned cytotoxic T lymphocytes

    PubMed Central

    1984-01-01

    Extracts of 125I-labeled cloned murine cytotoxic T lymphocytes (CTL) were immunoprecipitated with alloantisera to the cloned CTL and rabbit antisera to beta-2 microglobulin. Polyacrylamide gel electrophoresis (PAGE) of the specific precipitates revealed, as expected, 125I-labeled components that corresponded to products of class I genes of the major histocompatibility complex (MHC). However, additional class I gene products of relatively low apparent molecular weight (Mr) were also observed. Similar analyses of spleen cells from a variety of MHC- congenic mouse strains suggested that the class I molecules of relatively low Mr are encoded in the Qa-2 region of the MHC, and this was confirmed by immunoprecipitation with a monoclonal antibody to Qa- 2. Surprisingly, however, the cell surface Qa-2 molecules of different CTL clones differed in Mr, in isoelectric focusing (IEF) pattern, and in the number of distinguishable molecules expressed per clone: some clones seemed to express only a single Qa-2-encoded molecule while others expressed two distinct ones. Treatment of the immunoprecipitated Qa-2 with endoglycosidase F (Endo F) resulted in a decrease in Mr of approximately 5,000-6,000, corresponding to the expected loss of N- linked oligosaccharides, but the decrease did not eliminate structural variability among the clones. Structural diversity of the Qa-2-encoded molecules expressed on CTL could arise because CTL clones differ (a) in the particular Qa-2 genes they express, (b) in the way they splice Qa-2 gene transcripts or, perhaps, (c) in Endo F-resistant oligosaccharides on their Qa-2 molecules. PMID:6333483

  7. Generation of cytotoxic T lymphocytes (CTL) with phorbol ester and calcium ionophore

    SciTech Connect

    Tuttle, T.M.; Bear, H.D. )

    1991-03-15

    Stimulation of lymphocytes with viable tumor cells can induce cytotoxic T lymphocytes (CTL) against autologous tumor. However, sufficient numbers of tumor cells are not always available for such stimulation, and high dose interleukin-2 (IL-2) is often required for growth. Using the weakly immunogenic methylcholanthrene-induced sarcoma MCA105, the authors demonstrate here that CTLs can be expected by pharmacologic manipulation of protein kinase C (PKC) and intracellular calcium with phorbol dibutyrate (PD-Bu) and ionomycin (Io), respectively. Lymphocytes were obtained from the spleens and ipsilateral popliteal draining lymph nodes (DLN) 10 days after the footpad injection of viable MCA105 tumor cells. The cells were stimulated with autologous tumor and 20U/ml IL-2 for 7 days and then treated with PDBu and Io and expanded in culture with 20U/ml IL-2 for an additional 14 days. The lymphocytes from the spleens and DLNs demonstrated significant expansion and marked cytotoxicity against MCA105. In another regimen, lymphocytes from the DLNs of tumor-bearing mice were stimulated directly with PDBu and Io without prior in vitro exposure to autologous tumor and expanded in culture with 20U/ml IL-2. The expansion of these lymphocytes was 500 fold and the cytotoxicity against MCA 105 remained high. Lymphocytes expanded with PDBu and Io also killed MCA102, but normal spleen cells expanded in the same way had no cytotoxic activity. The authors conclude that PKC activators coupled with calcium ionophores and low-dose IL-2 can generate CTL when little or no antigen is available.

  8. CD4(+)/CD8(+) T-lymphocyte Ratio: Effects of Rehydration before Exercise in Dehydrated Men

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.; Jackson, Catherine G. R.; Lawless, Desales

    1995-01-01

    Effects of fluid ingestion on CD4+/CD8+ T-lymphocyte cell ratios were measured in four dehydrated men (ages 30-46 yr) before and after 70 min of supine submaximal (71 % VO(sub 2max) lower extremity cycle exercise. Just before exercise, Evans blue dye was injected for measurement of plasma volume. The subjects then drank one of six fluid formulations (12 ml/kg) in 3-4 min. All six mean post-hydration (pre-exercise) CD4+/CD8+ ratios (Becton-Dickinson Fluorescence Activated Cell Sorter and FACScan Consort-30 software program were below the normal range of 1.2-1.5; mean (+/- SE) and range were 0.77 +/- 0.12 and 0.39-1.15, respectively. The post-exercise ratios increased: mean = 1.36 =/- 0.15 (P less than 0.05) and range = 0.98-1.98. Regression of mean CD4+/CD8+ ratios on mean plasma osmolality resulted in pre- and post-exercise correlation coefficients of -0.76 (P less than 0.10) and -0.92 (P less than 0.01), respectively. The decreased pre-exercise ratios (after drinking) were probably not caused by the Evans blue dye but appeared to be associated more with the stress (osmotic) of dehydration. The increased post-exercise ratios to normal levels accompanied the rehydration and were not due to the varied electrolyte and osmotic concentrations of the ingested fluids or to the varied vascular volume shifts during exercise. Thus, the level of subject hydration and plasma osmotality may be factors involved in the mechanism of immune system modulation induced by exercise.

  9. B and T lymphocyte attenuator restricts the protective immune response against experimental malaria.

    PubMed

    Adler, Guido; Steeg, Christiane; Pfeffer, Klaus; Murphy, Theresa L; Murphy, Kenneth M; Langhorne, Jean; Jacobs, Thomas

    2011-11-15

    The immune response against the blood stage of malaria has to be tightly regulated to allow for vigorous antiplasmodial activity while restraining potentially lethal immunopathologic damage to the host like cerebral malaria. Coinhibitory cell surface receptors are important modulators of immune activation. B and T lymphocyte attenuator (BTLA) (CD272) is a coinhibitory receptor expressed by most leukocytes, with the highest expression levels on T and B cells, and is involved in the maintenance of peripheral tolerance by dampening the activation of lymphocytes. The function of BTLA is described in several models of inflammatory disorders and autoimmunity, but its function in infectious diseases is less well characterized. Also, little is known about the influence of BTLA on non-T cells. In this study, we analyzed the function of BTLA during blood-stage malaria infection with the nonlethal Plasmodium yoelii strain 17NL. We show that BTLA knockout mice exhibit strongly reduced parasitemia and clear the infection earlier compared with wild-type mice. This increased resistance was seen before the onset of adaptive immune mechanisms and even in the absence of T and B cells but was more pronounced at later time points when activation of T and B cells was observed. We demonstrate that BTLA regulates production of proinflammatory cytokines in a T cell-intrinsic way and B cell intrinsically regulates the production of P. yoelii 17NL-specific Abs. These results indicate that the coinhibitory receptor BTLA plays a critical role during experimental malaria and attenuates the innate as well as the subsequent adaptive immune response.

  10. An alternative mode of CD43 signal transduction activates pro-survival pathways of T lymphocytes.

    PubMed

    Bravo-Adame, Maria Elena; Vera-Estrella, Rosario; Barkla, Bronwyn J; Martínez-Campos, Cecilia; Flores-Alcantar, Angel; Ocelotl-Oviedo, Jose Pablo; Pedraza-Alva, Gustavo; Rosenstein, Yvonne

    2017-01-01

    CD43 is one of the most abundant co-stimulatory molecules on a T-cell surface; it transduces activation signals through its cytoplasmic domain, contributing to modulation of the outcome of T-cell responses. The aim of this study was to uncover new signalling pathways regulated by this sialomucin. Analysis of changes in protein abundance allowed us to identify pyruvate kinase isozyme M2 (PKM2), an enzyme of the glycolytic pathway, as an element potentially participating in the signalling cascade resulting from the engagement of CD43 and the T-cell receptor (TCR). We found that the glycolytic activity of this enzyme was not significantly increased in response to TCR+CD43 co-stimulation, but that PKM2 was tyrosine phosphorylated, suggesting that it was performing moonlight functions. We report that phosphorylation of both Y(105) of PKM2 and of Y(705) of signal transducer and activator of transcription 3 was induced in response to TCR+CD43 co-stimulation, resulting in activation of the mitogen-activated protein kinase kinase 5/extracellular signal-regulated kinase 5 (MEK5/ERK5) pathway. ERK5 and the cAMP response element binding protein (CREB) were activated, and c-Myc and nuclear factor-κB (p65) nuclear localization, as well as Bad phosphorylation, were augmented. Consistent with this, expression of human CD43 in a murine T-cell hybridoma favoured cell survival. Altogether, our data highlight novel signalling pathways for the CD43 molecule in T lymphocytes, and underscore a role for CD43 in promoting cell survival through non-glycolytic functions of metabolic enzymes.

  11. An antigenic threshold for maintaining human immunodeficiency virus type 1-specific cytotoxic T lymphocytes.

    PubMed Central

    Jin, X.; Ogg, G.; Bonhoeffer, S.; Safrit, J.; Vesanen, M.; Bauer, D.; Chen, D.; Cao, Y.; Demoitie, M. A.; Zhang, L.; Markowitz, M.; Nixon, D.; McMichael, A.; Ho, D. D.

    2000-01-01

    BACKGROUND: Using the lymphocytic choriomeningitis virus (LCMV) model in mice, a number of studies show that memory cytotoxic T-lymphocyte (CTL) responses are maintained in the presence of continuous antigenic stimulation. Yet, other groups found that memory CTL specific for LCMV could last for a lifetime in mice without viral antigens. Thus, the extent to which an antigen is required for the maintenance of virus-specific CTL remains controversial. In humans, very few studies have been conducted to investigate the relationship between the quantity of antigen and the magnitude of CTL responses. MATERIALS AND METHODS: We quantified CTL precursors (CTLp) using a limiting-dilution analysis (LDA) and CTL effectors (CTLe) using a new Major Histocompatibility Complex (MHC) class I tetramer technology in six long-term nonprogressors (LTNPs) with human immunodeficiency virus type-1 (HIV-1) infection, as well as in eight patients whose viral loads were well suppressed by antiretroviral therapy. The viremia levels in these patients were measured using an reverse transcription polymerase chain reaction (RT-PCR) assay. The proviral DNA load in peripheral blood mononuclear cell (PBMC) was also measured by PCR in four LTNPs. RESULTS: The LTNPs had high levels of HIV-1-specific memory CTLp and CTLe, while maintaining a low plasma viral load. Despite also having low viral loads, patients whose plasma viremia was well-suppressed by effective therapy had low levels of CTLe. CONCLUSIONS: Our findings suggest that a complex, rather than a monotonic, relationship exists between CTL levels and HIV-1 viremia, including what appears to be an antigenic threshold for the maintenance of CTL at a measurable level. Under conditions of "antigen excess,", CTLe levels correlate inversely with viral load. On the other hand, under conditions that are "antigen limited," the correlation appears to be direct. PMID:11071274

  12. Depletion of T lymphocytes ameliorates cardiac fibrosis in streptozotocin-induced diabetic cardiomyopathy.

    PubMed

    Abdullah, Chowdhury S; Li, Zhao; Wang, Xiuqing; Jin, Zhu-Qiu

    2016-10-01

    T cell infiltration has been associated with increased coronary heart disease risk in patients with diabetes mellitus. Effect of modulation of T cell trafficking on diabetes-induced cardiac fibrosis has yet to be determined. Therefore, our aim was to investigate the circulatory T cell depletion-mediated cardioprotection in streptozotocin-induced diabetic cardiomyopathy. Fingolimod (FTY720), an immunomodulatory drug, was tested in wild-type (WT) C57BL/6 and recombination activating gene 1 (Rag1) knockout (KO) mice without mature lymphocytes in streptozotocin-induced type 1 diabetic model. FTY720 (0.3mg/kg/day) was administered intraperitoneally daily for the first 4weeks with interim 3weeks then resumed for another 4weeks in 11weeks study period. T lymphocyte counts, cardiac histology, function, and fibrosis were examined in diabetic both WT and KO mice. FTY720 reduced both CD4(+) and CD8(+) T cells in diabetic WT mice. FTY720-treated diabetic WT mouse myocardium showed reduction in CD3 T cell infiltration and decreased expression of S1P1 and TGF-β1 in cardiac tissue. Fibrosis was reduced after FTY720 treatment in diabetic WT mice. Rag1 KO mice exhibited no CD4(+) and CD8(+) T cells in the blood and CD3 T cells in the heart. Diabetic Rag1 KO mouse hearts appeared no fibrosis and exhibited preserved myocardial contractility. FTY720-induced antifibrosis was abolished in diabetic Rag1 KO mice. These findings demonstrate that chronic administration with FTY720 induces lymphopenia and protects diabetic hearts in WT mice whereas FTY720 increases cardiac fibrosis and myocardial dysfunction in diabetic Rag1 KO mice without mature lymphocytes.

  13. Expression of CD8alpha identifies a distinct subset of effector memory CD4+ T lymphocytes.

    PubMed

    Macchia, Iole; Gauduin, Marie-Claire; Kaur, Amitinder; Johnson, R Paul

    2006-10-01

    Circulating CD4+ CD8+ T lymphocytes have been described in the peripheral blood of humans and several animal species. However, the origin and functional properties of these cells remain poorly understood. In the present study, we evaluated the frequency, phenotype and function of peripheral CD4+ CD8+ T cells in rhesus macaques. Two distinct populations of CD4+ CD8+ T cells were identified: the dominant one was CD4hi CD8lo and expressed the CD8alphaalpha homodimer, while the minor population was CD4lo CD8hi and expressed the CD8alphabeta heterodimer. The majority of CD4hi CD8alphalo T cells exhibited an activated effector/memory phenotype (CCR5lo CD7- CD28- HLA-DR+) and expressed relatively high levels of granzyme B. Intracellular cytokine staining assays demonstrated that the frequency of cytomegalovirus-specific T cells was enriched five-fold in CD4hi CD8alphalo T cells compared to single-positive CD4+ T cells, whereas no consistent enrichment was observed for simian immunodeficiency virus (SIV)-specific T cells. Cross-sectional studies of SIV-infected animals demonstrated that the frequency of CD4hi CD8alphalo T cells was lower in wild-type SIV-infected animals compared to uninfected controls, although prospective studies of SIV-infected animals demonstrated depletion of CD4hi CD8alphalo lymphocytes only in a subset of animals. Taken together, these data suggest that CD4+ T cells expressing CD8alpha represent an effector/memory subset of CD4+ T cells and that this cell population can be depleted during the course of SIV infection.

  14. T-lymphocyte homing: an underappreciated yet critical hurdle for successful cancer immunotherapy.

    PubMed

    Sackstein, Robert; Schatton, Tobias; Barthel, Steven R

    2017-03-27

    Advances in cancer immunotherapy have offered new hope for patients with metastatic disease. This unfolding success story has been exemplified by a growing arsenal of novel immunotherapeutics, including blocking antibodies targeting immune checkpoint pathways, cancer vaccines, and adoptive cell therapy (ACT). Nonetheless, clinical benefit remains highly variable and patient-specific, in part, because all immunotherapeutic regimens vitally hinge on the capacity of endogenous and/or adoptively transferred T-effector (Teff) cells, including chimeric antigen receptor (CAR) T cells, to home efficiently into tumor target tissue. Thus, defects intrinsic to the multi-step T-cell homing cascade have become an obvious, though significantly underappreciated contributor to immunotherapy resistance. Conspicuous have been low intralesional frequencies of tumor-infiltrating T-lymphocytes (TILs) below clinically beneficial threshold levels, and peripheral rather than deep lesional TIL infiltration. Therefore, a Teff cell 'homing deficit' may arguably represent a dominant factor responsible for ineffective immunotherapeutic outcomes, as tumors resistant to immune-targeted killing thrive in such permissive, immune-vacuous microenvironments. Fortunately, emerging data is shedding light into the diverse mechanisms of immune escape by which tumors restrict Teff cell trafficking and lesional penetrance. In this review, we scrutinize evolving knowledge on the molecular determinants of Teff cell navigation into tumors. By integrating recently described, though sporadic information of pivotal adhesive and chemokine homing signatures within the tumor microenvironment with better established paradigms of T-cell trafficking under homeostatic or infectious disease scenarios, we seek to refine currently incomplete models of Teff cell entry into tumor tissue. We further summarize how cancers thwart homing to escape immune-mediated destruction and raise awareness of the potential impact of immune

  15. Retrovirally transduced murine T lymphocytes expressing FasL mediate effective killing of prostate cancer cells

    PubMed Central

    Symes, JC; Siatskas, C; Fowler, DH; Medin, JA

    2010-01-01

    Adoptively transferred T cells possess anticancer activities partially mediated by T-cell FasL engagement of Fas tumor targets. However, antigen-induced T-cell activation and clonal expansion, which stimulates FasL activity, is often inefficient in tumors. As a gene therapy approach to overcome this obstacle, we have created oncoretroviral vectors to overexpress FasL or non-cleavable FasL (ncFasL) on murine T cells of a diverse T-cell receptor repertoire. Expression of c-FLIP was also engineered to prevent apoptosis of transduced cells. Retroviral transduction of murine T lymphocytes has historically been problematic, and we describe optimized T-cell transduction protocols involving CD3/CD28 co-stimulation of T cells, transduction on ice using concentrated oncoretrovirus, and culture with IL-15. Genetically modified T cells home to established prostate cancer tumors in vivo. Co-stimulated T cells expressing FasL, ncFasL and ncFasL/c-FLIP each mediated cytotoxicity in vitro against RM-1 and LNCaP prostate cancer cells. To evaluate the compatibility of this approach with current prostate cancer therapies, we exposed RM-1, LNCaP, and TRAMP-C1 cells to radiation, mitoxantrone, or docetaxel. Fas and H-2b expression were upregulated by these methods. We have developed a novel FasL-based immuno-gene therapy for prostate cancer that warrants further investigation given the apparent constitutive and inducible Fas pathway expression in this malignancy. PMID:19096446

  16. Extended Interferon-Alpha Therapy Accelerates Telomere Length Loss in Human Peripheral Blood T Lymphocytes

    PubMed Central

    O'Bryan, Joel M.; Potts, James A.; Bonkovsky, Herbert L.; Mathew, Anuja; Rothman, Alan L.

    2011-01-01

    Background Type I interferons have pleiotropic effects on host cells, including inhibiting telomerase in lymphocytes and antiviral activity. We tested the hypothesis that long-term interferon treatment would result in significant reduction in average telomere length in peripheral blood T lymphocytes. Methods/Principal Findings Using a flow cytometry-based telomere length assay on peripheral blood mononuclear cell samples from the Hepatitis-C Antiviral Long-term Treatment against Cirrhosis (HALT-C) study, we measured T cell telomere lengths at screening and at months 21 and 45 in 29 Hepatitis-C virus infected subjects. These subjects had failed to achieve a sustained virologic response following 24 weeks of pegylated-interferon-alpha plus ribavirin treatment and were subsequently randomized to either a no additional therapy group or a maintenance dose pegylated-IFNα group for an additional 3.5 years. Significant telomere loss in naïve T cells occurred in the first 21 months in the interferon-alpha group. Telomere losses were similar in both groups during the final two years. Expansion of CD8+CD45RA+CD57+ memory T cells and an inverse correlation of alanine aminotransferase levels with naïve CD8+ T cell telomere loss were observed in the control group but not in the interferon-alpha group. Telomere length at screening inversely correlated with Hepatitis-C viral load and body mass index. Conclusions/Significance Sustained interferon-alpha treatment increased telomere loss in naïve T cells, and inhibited the accumulation of T cell memory expansions. The durability of this effect and consequences for immune senescence need to be defined. PMID:21829595

  17. Umbilical Cord Tissue-Derived Mesenchymal Stem Cells Induce T Lymphocyte Apoptosis and Cell Cycle Arrest by Expression of Indoleamine 2, 3-Dioxygenase

    PubMed Central

    Li, Xiuying; Xu, Zhuo; Bai, Jinping; Yang, Shuyuan; Zhao, Shuli; Zhang, Yingjie; Chen, Xiaodong

    2016-01-01

    It has been reported that human mesenchymal stem cells are able to inhibit T lymphocyte activation; however, the discrepancy among different sources of MSCs is not well documented. In this study, we have compared the MSCs from bone marrow (BM), adipose tissue (AT), placenta (PL), and umbilical cord (UC) to determine which one displayed the most efficient immunosuppressive effects on phytohemagglutinin-induced T cell proliferation. Among them we found that hUC-MSC has the strongest effects on inhibiting T cell proliferation and is chosen to do the further study. We observed that T lymphocyte spontaneously released abundant IFN-γ. And IFN-γ secreted by T lymphocyte could induce the expression of indoleamine 2, 3-dioxygenase (IDO) in hUC-MSCs. IDO was previously reported to induce T lymphocyte apoptosis and cell cycle arrest in S phase. When cocultured with hUC-MSCs, T lymphocyte expression of caspase 3 was significantly increased, while Bcl2 and CDK4 mRNA expression decreased dramatically. Addition of 1-methyl tryptophan (1-MT), an IDO inhibitor, restored T lymphocyte proliferation, reduced apoptosis, and induced resumption of the cell cycle. In addition, the changes in caspase 3, CDK4, and Bcl2 expression were reversed by 1-MT. These findings demonstrate that hUC-MSCs induce T lymphocyte apoptosis and cell cycle arrest by expressing abundant IDO and provide an explanation for some of the immunomodulatory effects of MSCs. PMID:27418932

  18. Recombinant human erythropoietin treatment of chronic renal failure patients normalizes altered phenotype and proliferation of CD4-positive T lymphocytes.

    PubMed

    Lisowska, Katarzyna A; Debska-Slizien, Alicja; Radzka, Monika; Witkowski, Jacek M; Rutkowski, Boleslaw; Bryl, Ewa

    2010-03-01

    Patients with chronic renal failure (CRF) receive recombinant human erythropoietin (rhEPO) for the correction of anemia. However, rhEPO also has an immunomodulatory effect. Detailed changes of phenotype and function of CD4(+) T lymphocytes in CRF patients receiving rhEPO have not been reported yet; their study may bring insight into understanding of this immunomodulatory action of rhEPO. Two groups of CRF patients were included into the study: those treated; and those not receiving rhEPO. The expression of activation markers on CD4(+) lymphocytes was measured with flow cytometry, both ex vivo and in vitro. The kinetics of CD4(+) T lymphocytes proliferation was calculated using a dividing cells tracing method and numerical approach. Significantly higher percentages of CD4(+)CD95(+), CD4(+)HLA-DR(+) cells, and lower percentages of CD4(+)CD69(+) and CD4(+)CD28(+) cells were observed in both rhEPO-treated and untreated patients when compared with healthy controls. Changes in the proportions of CD4(+)CD28(+) and CD4(+)HLA-DR(+) subpopulations were dependent on the type of rhEPO, being more pronounced for rhEPObeta. CD4(+) lymphocytes from untreated patients exhibited decreased expression of CD28 and CD69 after stimulation in vitro, whereas the expression of these antigens on lymphocytes of rhEPO-treated patients was similar to that observed in healthy controls. Fewer CD4(+)CD28(+) T lymphocytes of untreated patients proliferated in vitro; these cells had longer G0-->G1 time, which negatively correlated with surface expression of CD28. Our study confirms that rhEPO treatment normalizes activation parameters of CD4(+) T lymphocytes and their proliferative capacity, which could explain earlier described immunomodulatory effects of rhEPO in patients suffering from CRF.

  19. CCR5 susceptibility to ligand-mediated down-modulation differs between human T lymphocytes and myeloid cells.

    PubMed

    Fox, James M; Kasprowicz, Richard; Hartley, Oliver; Signoret, Nathalie

    2015-07-01

    CCR5 is a chemokine receptor expressed on leukocytes and a coreceptor used by HIV-1 to enter CD4(+) T lymphocytes and macrophages. Stimulation of CCR5 by chemokines triggers internalization of chemokine-bound CCR5 molecules in a process called down-modulation, which contributes to the anti-HIV activity of chemokines. Recent studies have shown that CCR5 conformational heterogeneity influences chemokine-CCR5 interactions and HIV-1 entry in transfected cells or activated CD4(+) T lymphocytes. However, the effect of CCR5 conformations on other cell types and on the process of down-modulation remains unclear. We used mAbs, some already shown to detect distinct CCR5 conformations, to compare the behavior of CCR5 on in vitro generated human T cell blasts, monocytes and MDMs and CHO-CCR5 transfectants. All human cells express distinct antigenic forms of CCR5 not detected on CHO-CCR5 cells. The recognizable populations of CCR5 receptors exhibit different patterns of down-modulation on T lymphocytes compared with myeloid cells. On T cell blasts, CCR5 is recognized by all antibodies and undergoes rapid chemokine-mediated internalization, whereas on monocytes and MDMs, a pool of CCR5 molecules is recognized by a subset of antibodies and is not removed from the cell surface. We demonstrate that this cell surface-retained form of CCR5 responds to prolonged treatment with more-potent chemokine analogs and acts as an HIV-1 coreceptor. Our findings indicate that the regulation of CCR5 is highly specific to cell type and provide a potential explanation for the observation that native chemokines are less-effective HIV-entry inhibitors on macrophages compared with T lymphocytes.

  20. Bovine WC1(+) γδ T lymphocytes modify monocyte-derived macrophage responses during early Mycobacterium avium subspecies paratuberculosis infection.

    PubMed

    Baquero, Monica M; Plattner, Brandon L

    2016-02-01

    Following Mycobacterium avium subspecies paratuberculosis (Map) infection, some calves are apparently able to successfully clear the pathogen whereas others become persistently infected; however the reasons for this remain unknown. The importance of innate immunity, and in particular the role of γδ T lymphocytes, during early anti-mycobacterial immune response is recognized but specific mechanisms remain incompletely characterized. The objective of this study was to investigate how bovine WC1(+) γδ T lymphocytes mediate macrophage function during early Map infection. To achieve this objective, Map-infected monocyte-derived macrophages (MDMs) were co-cultured either in direct contact with, or separated by a semi-permeable membrane from, autologous WC1(+) γδ T lymphocytes. Nitrites, IL-17A, IFN-γ, IL-4 and IL-10 from cell culture supernatants were measured. Expression of CD25 on WC1(+) γδ T lymphocytes, expression of MHC-I and MHC-II on MDMs and the viability of Map recovered from MDM cultures 72h after Map infection were also assessed. Map viability was significantly reduced when WC1(+) γδ T lymphocytes were co-cultured in direct contact with Map-infected MDMs. Both MDMs and WC1(+) γδ T lymphocytes generated increased concentrations of IFN-γ and IL-4 in our system, and MDM/WC1(+) γδ T lymphocyte synergism was identified for IFN-γ production. MDMs but not WC1(+) γδ T lymphocytes were a significant source of IL-17A. The presence of WC1(+) γδ T lymphocytes was associated with higher expression of MHC-I on MDMs and increased concentration of nitrites in supernatants 72h after Map infection. In conclusion, this study showed that WC1(+) γδ lymphocytes had differential effects on Map-infected macrophages in vitro.

  1. Interaction of dendritic cells and T lymphocytes for the therapeutic effect of Dangguiliuhuang decoction to autoimmune diabetes.

    PubMed

    Liu, Tingting; Cao, Hui; Ji, Yachun; Pei, Yufeng; Yu, Zhihong; Quan, Yihong; Xiang, Ming

    2015-09-11

    In traditional Chinese medicine (TCM), Dangguiliuhuang decoction (DGLHD) is an effective treatment of autoimmune diabetes. Here, we studied potential anti-diabetic mechanisms of DGLHD in a non-obese diabetic (NOD) mouse model. In vitro, DGLHD and individual active ingredients enhanced glucose uptake in HepG2 cells, inhibited T lymphocyte proliferation, and suppressed dendritic cells (DCs) function. In vivo, DGLHD significantly inhibited insulitis, delayed the onset and development of diabetes, promoted insulin secretion and sensitivity, and balanced partially normalized Th1 and Th2 cytokines in NOD mice. In addition, DGLHD increased α1-antitrypsin (AAT-1), Bcl-2, and CyclinD1, and decreased Bax levels in pancreas, spleen, thymus, DCs, and a NIT-1 cell line, all consistent with protecting and repairing islet β cell. More detailed studies indicated that DGLHD regulated the maturation and function of DCs, decreased the percentage of merocytic dendritic cells (mcDCs) subset, and increased programmed death ligand-1 (PD-L1) expression in DCs. DGLHD also impeded T lymphocyte proliferation and promoted regulatory T cells (T(regs)) differentiation in vivo. A JAK2-STAT3-dependent pathway was involved in the suppression by DGLHD of interactions between DCs and T lymphocyte. The experiments implicated five active ingredients in specific anti-diabetic actions of DGLHD. The results demonstrated the reasonable composition of the formula.

  2. Regulation of the energy sensor AMP-activated protein kinase by antigen receptor and Ca2+ in T lymphocytes

    PubMed Central

    Tamás, Peter; Hawley, Simon A.; Clarke, Rosemary G.; Mustard, Kirsty J.; Green, Kevin; Hardie, D. Grahame; Cantrell, Doreen A.

    2006-01-01

    The adenosine monophosphate (AMP)–activated protein kinase (AMPK) has a crucial role in maintaining cellular energy homeostasis. This study shows that human and mouse T lymphocytes express AMPKα1 and that this is rapidly activated in response to triggering of the T cell antigen receptor (TCR). TCR stimulation of AMPK was dependent on the adaptors LAT and SLP76 and could be mimicked by the elevation of intracellular Ca2+ with Ca2+ ionophores or thapsigargin. AMPK activation was also induced by energy stress and depletion of cellular adenosine triphosphate (ATP). However, TCR and Ca2+ stimulation of AMPK required the activity of Ca2+–calmodulin-dependent protein kinase kinases (CaMKKs), whereas AMPK activation induced by increased AMP/ATP ratios did not. These experiments reveal two distinct pathways for the regulation of AMPK in T lymphocytes. The role of AMPK is to promote ATP conservation and production. The rapid activation of AMPK in response to Ca2+ signaling in T lymphocytes thus reveals that TCR triggering is linked to an evolutionally conserved serine kinase that regulates energy metabolism. Moreover, AMPK does not just react to cellular energy depletion but also anticipates it. PMID:16818670

  3. IL-2 Expression and T lymphocyte Phenotyping in Young Children Suffering from Upper Respiratory Tract Infection with Streptococcus Pyogenes

    PubMed Central

    Guadalupe Ramirez-Valles, Eda; Dayali Gutierrez-Martinez, Verónica; Cervantes-Flores, Maribel; Ruiz-Baca, Estela; Alvarado-Esquivel, Cosme

    2016-01-01

    T cells are components of adaptive immunity and are involved in the resolution of respiratory infections, which are a major cause of morbidity and mortality in young children worldwide. Activation and differentiation of T cells is given mostly by the cytokine IL-2. This study aimed to determine the phenotype of T cells and IL-2 expression in children suffering from upper respiratory tract infection with Streptococcus pyogenes (S. pyogenes). For this purpose, IL-2 expression at its gene and protein levels and quantitation of CD4+ and CD8+ T lymphocytes were assessed in children aged 0-5 years old suffering from upper respiratory tract infection with S. pyogenes and healthy children of the same age. Children with S. pyogenes infection had a higher expression of IL-2 gene and a lower level of this cytokine expression at protein level than healthy children. The numbers of CD4+ T lymphocytes were similar among the groups. In contrast, difference in the numbers of CD8+ T lymphocytes among the groups was found. We conclude that infections by S. pyogenes in young children lead to an increased expression of IL-2 mRNA. PMID:27493590

  4. Sequential immunological studies on an asbestos-exposed population. I. Factors affecting peripheral blood leucocytes and T lymphocytes.

    PubMed Central

    Wagner, M M; Campbell, M J; Edwards, R E

    1979-01-01

    Peripheral blood leucocyte counts, and E binding rosettes were measured on 138 men on five separate occasions. Little effect was seen from age, or length of asbestos exposure. Overall the most marked effect was that obtained from smoking. Most relevant was an increase in percentage of E-rosettes read after 1 1/2 hrs, which was obtained in the group of those with radiological evidence of fibrosis who smoked. Restricted to subjects with small opacities, those who smoke have a significantly higher (P less than 0.05) percentage E 1 1/2 hr rosettes than those who do not smoke. (Percentage E rosettes read overnight remained unaltered by smoking or X-ray). This increase was found on each occasion that it was measured. Since the absolute number of T lymphocytes rosetting at 1 1/2 hr did not increase, it is suggested that there is either no stimulation of the central pool of T lymphocytes or a decrease in the absolute number of T lymphocytes which could only rosette overnight. PMID:316753

  5. Interaction of dendritic cells and T lymphocytes for the therapeutic effect of Dangguiliuhuang decoction to autoimmune diabetes

    PubMed Central

    Liu, Tingting; Cao, Hui; Ji, Yachun; Pei, Yufeng; Yu, Zhihong; Quan, Yihong; Xiang, Ming

    2015-01-01

    In traditional Chinese medicine (TCM), Dangguiliuhuang decoction (DGLHD) is an effective treatment of autoimmune diabetes. Here, we studied potential anti-diabetic mechanisms of DGLHD in a non-obese diabetic (NOD) mouse model. In vitro, DGLHD and individual active ingredients enhanced glucose uptake in HepG2 cells, inhibited T lymphocyte proliferation, and suppressed dendritic cells (DCs) function. In vivo, DGLHD significantly inhibited insulitis, delayed the onset and development of diabetes, promoted insulin secretion and sensitivity, and balanced partially normalized Th1 and Th2 cytokines in NOD mice. In addition, DGLHD increased α1-antitrypsin (AAT-1), Bcl-2, and CyclinD1, and decreased Bax levels in pancreas, spleen, thymus, DCs, and a NIT-1 cell line, all consistent with protecting and repairing islet β cell. More detailed studies indicated that DGLHD regulated the maturation and function of DCs, decreased the percentage of merocytic dendritic cells (mcDCs) subset, and increased programmed death ligand-1 (PD-L1) expression in DCs. DGLHD also impeded T lymphocyte proliferation and promoted regulatory T cells (Tregs) differentiation in vivo. A JAK2-STAT3-dependent pathway was involved in the suppression by DGLHD of interactions between DCs and T lymphocyte. The experiments implicated five active ingredients in specific anti-diabetic actions of DGLHD. The results demonstrated the reasonable composition of the formula. PMID:26358493

  6. Circulating T lymphocyte subsets, cytokines, and immune checkpoint inhibitors in patients with bipolar II or major depression: a preliminary study

    PubMed Central

    Wu, Wei; Zheng, Ya-li; Tian, Li-ping; Lai, Jian-bo; Hu, Chan-chan; Zhang, Peng; Chen, Jing-kai; Hu, Jian-bo; Huang, Man-li; Wei, Ning; Xu, Wei-juan; Zhou, Wei-hua; Lu, Shao-jia; Lu, Jing; Qi, Hong-li; Wang, Dan-dan; Zhou, Xiao-yi; Duan, Jin-feng; Xu, Yi; Hu, Shao-hua

    2017-01-01

    This study aimed to investigate the less known activation pattern of T lymphocyte populations and immune checkpoint inhibitors on immunocytes in patients with bipolar II disorder depression (BD) or major depression (MD). A total of 23 patients with BD, 22 patients with MD, and 20 healthy controls (HCs) were recruited. The blood cell count of T lymphocyte subsets and the plasma level of cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) were selectively investigated. The expression of T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), programmed cell death protein 1 (PD-1) and its ligands, PD-L1 and PD-L2, on T lymphocytes and monocytes, was detected. In results, blood proportion of cytotoxic T cells significantly decreased in BD patients than in either MD patients or HCs. The plasma level of IL-6 increased in patients with BD and MD. The expression of TIM-3 on cytotoxic T cells significantly increased, whereas the expression of PD-L2 on monocytes significantly decreased in patients with BD than in HCs. These findings extended our knowledge of the immune dysfunction in patients with affective disorders. PMID:28074937

  7. Effects of strong magnetic fields on cell growth and radiation response of human T-lymphocytes in culture.

    PubMed

    Norimura, T; Imada, H; Kunugita, N; Yoshida, N; Nikaido, M

    1993-06-01

    Experiments were undertaken in order to verify whether or not a strong magnetic field would have any biological effects on the cell growth, viability and radiation response of mammalian cells. Magnetic field exposures were conducted using a superconducting magnet with freshly-isolated human peripheral blood T-lymphocytes maintained at their normal growing temperature of 37 degrees C. The static magnetic fields with intensities up to 6.3-tesla (T) exerted little influence on the cell growth and viability of actively-growing T-lymphocytes under normal cell-culture conditions. On the other hand, the T cells exposed to the magnetic fields (4 T-6.3 T) during PHA stimulation were inhibited in their cell growth when compared to controls. The effects of the magnetic fields with intensities up to 2 T on cell growth properties, however, were minimal in this system. Also, the radiosensitivity of T-lymphocytes previously exposed to the strong magnetic fields was more sensitive than that of control cells. These results suggest that exposure to a static magnetic field of 4 T or stronger might lead to physiological and growth abnormalities at the cellular level.

  8. High IFN-gamma production of individual CD8 T lymphocytes is controlled by CD152 (CTLA-4).

    PubMed

    Pandiyan, Pushpa; Hegel, J Kolja E; Krueger, Manuela; Quandt, Dagmar; Brunner-Weinzierl, Monika C

    2007-02-15

    CD8 T cell expansion and cytokine production is needed to generate an effective defense against viral invasion of the host. These features of CD8 T lymphocytes are regulated, especially during primary responses, by positive and negative costimulation. We show in this study that surface expression of CD152 is highly up-regulated on activated CD8 T lymphocytes during primary immune responses, suggesting a prominent regulatory role. Indeed, production of the proinflammatory cytokine IFN-gamma, but not TNF-alpha, by CD8 T cells was inhibited by CD152 engagement. The inhibition was regulated independent of proliferation and IL-2 production, but dependent on the quality of the TCR signaling. We show that signals induced by CD152 on activated CD8 T lymphocytes reduce the frequency of IFN-gamma(high)-expressing cells. Our data also show that in activated CD8 T cells, the CD152-mediated inhibition of cytokine production is more pronounced than inhibition of their proliferation.

  9. Colchicum autumnale agglutinin activates all murine T-lymphocytes but does not induce the proliferation of all activated cells.

    PubMed

    Bemer, V; Van Damme, E J; Peumans, W J; Perret, R; Truffa-Bachi, P

    1996-08-25

    Plant lectins with mitogenic properties for T-lymphocytes have been particularly useful for the study of T-cell activation and effector functions. In the search for mitogenic lectins possessing activation features different from the ones associated with the already known mitogens, we found that an agglutinin isolated from Colchicum autumnale tubers, Colchicum autumnale agglutinin (CAA), possesses interesting properties. First, contrasting with the classical mitogens, CAA induces the proliferation of a fraction of the CD4+ and CD8+ mouse T-lymphocytes. Second, the CAA-induced proliferation requires MHC class II and CD4 molecules. Third, although only a fraction of T-cells enters into the cell cycle, all T-lymphocytes are activated and express high levels of the activation markers CD69 and CD44. Finally, CAA-stimulation is characterized by a particular pattern of the cytokine gene expression, reflected by the transcription of the IL2, IL5, and IFN-gamma genes, while the IL4 and IL10 genes remained silent. Taken together these data demonstrate that CAA activation does not conform to the pathway of T-cell triggering observed with classical mitogenes and represents a new tool for the analysis of T-cell activation.

  10. HIV infection of monocytes inhibits the T-lymphocyte proliferative response to recall antigens, via production of eicosanoids.

    PubMed Central

    Foley, P; Kazazi, F; Biti, R; Sorrell, T C; Cunningham, A L

    1992-01-01

    Human monocytes infected in vitro with human immunodeficiency virus (HIV) soon after adherence to plastic substrate demonstrated a significantly decreased ability to restimulate autologous immune T-lymphocyte proliferation after exposure to soluble (tetanus toxoid) and particulate [herpes simplex virus (HSV)] antigen. Incubation with the cyclo-oxygenase inhibitor, indomethacin (2-5 microM), prevented inhibition of antigen-stimulated lymphocyte proliferation. The inhibitory activity was identified in ultrafiltrates containing the low molecular weight fraction (less than 3000 MW) of supernatants from HIV-infected monocyte cultures. This activity was significantly and markedly reduced in similar ultrafiltrates prepared from indomethacin-treated cultures. Increased concentrations of prostaglandin E2 (PGE2) were detected in ultrafiltrates from HIV-infected monocyte cultures compared with uninfected cultures and cultures preincubated with indomethacin. Ultrafiltrates were inhibitory when added during the presentation of antigen to T lymphocytes but not when removed from monocyte cultures prior to the addition of lymphocytes. In addition, ultrafiltrates inhibited antigen-stimulated lymphocyte proliferation and PHA-induced lymphocyte proliferation to the same extent. These data indicate that cyclo-oxygenase products of arachidonic acid, including PGE2, are produced in excess by HIV-infected monocytes and that PGE2 and perhaps other cyclo-oxygenase products are implicated in the inhibition of antigen-stimulated lymphocyte proliferation via a direct effect on T lymphocytes. PMID:1572689

  11. Dengue virus-specific murine T-lymphocyte proliferation: serotype specificity and response to recombinant viral proteins.

    PubMed Central

    Rothman, A L; Kurane, I; Zhang, Y M; Lai, C J; Ennis, F A

    1989-01-01

    Definition of the T-lymphocyte responses to dengue viruses should aid in the development of safe and effective vaccines and help to explain the pathophysiology of dengue hemorrhagic fever and dengue shock syndrome. In this study, we demonstrated that dengue virus-specific T lymphocytes were detected in spleen cells from dengue virus-immune mice using an in vitro proliferation assay. Following immunization with a single dose of infectious dengue virus, murine lymphocytes showed increased proliferation when incubated in the presence of viral antigens of the same serotype but not in the presence of control antigens. Depletion experiments with antibody and complement showed that the population of responding cells expressed the Thy1+ L3T4+ Lyt2- phenotype. This indicates that the predominant proliferating cells are T lymphocytes of the helper-inducer phenotype. Dengue virus-specific memory lymphocyte responses were detectable for at least 22 weeks after immunization. The response to primary infection was primarily serotype specific, with some serotype cross-reactivity present at a low level. We demonstrated that lymphocytes from mice immunized with dengue 4 virus proliferate in response to a combination of dengue 4 virus C, pre-M, E, NS1, and NS2a proteins expressed in Sf9 cells with a recombinant baculovirus, and, to a lesser extent, to the dengue 4 virus E protein alone. PMID:2786087

  12. The natural killer T lymphocyte: a player in the complex regulation of autoimmune diabetes in non-obese diabetic mice

    PubMed Central

    Cardell, S L

    2006-01-01

    Manipulation of the immune response to specifically prevent autoaggression requires an understanding of the complex interactions that occur during the pathogenesis of autoimmunity. Much attention has been paid to conventional T lymphocytes recognizing peptide antigens presented by classical major histocompatibility complex (MHC) class I and II molecules, as key players in the destructive autoreactive process. A pivotal role for different types of regulatory T lymphocytes in modulating the development of disease is also well established. Lately, CD1d-restricted natural killer T (NKT) lymphocytes have been the subject of intense investigation because of their ability to regulate a diversity of immune responses. The non-classical antigen presenting molecule CD1d presents lipids and glycolipids to this highly specialized subset of T lymphocytes found in both humans and mice. From experimental models of autoimmunity, evidence is accumulating that NKT cells can protect from disease. One of the best studied is the murine type 1 diabetes model, the non-obese diabetic (NOD) mouse. While the NKT cell population was first recognized to be deficient in NOD mice, augmenting NKT cell activity has been shown to suppress the development of autoimmune disease in this strain. The mechanism by which CD1d-restricted T cells exert this function is still described incompletely, but investigations in NOD mice are starting to unravel specific effects of NKT cell regulation. This review focuses on the role of CD1d-restricted NKT cells in the control of autoimmune diabetes. PMID:16412042

  13. Vav1 and Rac Control Chemokine-promoted T Lymphocyte Adhesion Mediated by the Integrin α4β1D⃞

    PubMed Central

    García-Bernal, David; Wright, Natalia; Sotillo-Mallo, Elena; Nombela-Arrieta, César; Stein, Jens V.; Bustelo, Xosé R.; Teixidó, Joaquin

    2005-01-01

    The chemokine CXCL12 promotes T lymphocyte adhesion mediated by the integrin α4β1. CXCL12 activates the GTPase Rac, as well as Vav1, a guanine-nucleotide exchange factor for Rac, concomitant with up-regulation of α4β1-dependent adhesion. Inhibition of CXCL12-promoted Rac and Vav1 activation by transfection of dominant negative Rac or Vav1 forms, or by transfection of their siRNA, remarkably impaired the increase in T lymphocyte attachment to α4β1 ligands in response to this chemokine. Importantly, inhibition of Vav1 expression by RNA interference resulted in a blockade of Rac activation in response to CXCL12. Adhesions in flow chambers and soluble binding assays using these transfectants indicated that initial ligand binding and adhesion strengthening mediated by α4β1 were dependent on Vav1 and Rac activation by CXCL12. Finally, CXCL12-promoted T-cell transendothelial migration involving α4β1-mediated adhesion was notably inhibited by expression of dominant negative Vav1 and Rac. These results indicate that activation of Vav1-Rac signaling pathway by CXCL12 represents an important inside-out event controlling efficient up-regulation of α4β1-dependent T lymphocyte adhesion. PMID:15872091

  14. Induction of antigen-specific regulatory T lymphocytes by human dendritic cells expressing the glucocorticoid-induced leucine zipper.

    PubMed

    Hamdi, Haifa; Godot, Véronique; Maillot, Marie-Christine; Prejean, Maria Victoria; Cohen, Nicolas; Krzysiek, Roman; Lemoine, François M; Zou, Weiping; Emilie, Dominique

    2007-07-01

    Dendritic cells (DCs) determine whether antigen presentation leads to immune activation or to tolerance. Tolerance-inducing DCs (also called regulatory DCs) act partly by generating regulatory T lymphocytes (Tregs). The mechanism used by DCs to switch toward regulatory DCs during their differentiation is unclear. We show here that human DCs treated in vitro with glucocorticoids produce the glucocorticoid-induced leucine zipper (GILZ). Antigen presentation by GILZ-expressing DCs generates CD25(high)FOXP3(+)CTLA-4/CD152(+) and interleukin-10-producing Tregs inhibiting the response of CD4(+) and CD8(+) T lymphocytes. This inhibition is specific to the antigen presented, and only proliferating CD4(+) T lymphocytes express the Treg markers. Interleukin-10 is required for Treg induction by GILZ-expressing DCs. It is also needed for the suppressive function of Tregs. Antigen-presenting cells from patients treated with glucocorticoids generate interleukin-10-secreting Tregs ex vivo. These antigen-presenting cells produce GILZ, which is needed for Treg induction. Therefore, GILZ is critical for commitment of DCs to differentiate into regulatory DCs and to the generation of antigen-specific Tregs. This mechanism may contribute to the therapeutic effects of glucocorticoids.

  15. GILZ expression in human dendritic cells redirects their maturation and prevents antigen-specific T lymphocyte response.

    PubMed

    Cohen, Nicolas; Mouly, Enguerran; Hamdi, Haifa; Maillot, Marie-Christine; Pallardy, Marc; Godot, Véronique; Capel, Francis; Balian, Axel; Naveau, Sylvie; Galanaud, Pierre; Lemoine, François M; Emilie, Dominique

    2006-03-01

    Interleukin (IL)-10 and glucocorticoids (GCs) inhibit the ability of antigen-presenting dendritic cells (DCs) to stimulate T lymphocytes. We show that induction of GILZ (GC-induced leucine zipper) is involved in this phenomenon. IL-10, dexamethasone (DEX), and transforming growth factor (TGF)beta stimulate GILZ production in human immature DCs derived from monocytes and from CD34+ cells. GILZ is necessary and sufficient for DEX, IL-10, and TGFbeta modulation of CD80, CD83, CD86, immunoglobulin-like transcript (ILT)-3, and B7-H1 expression by DCs, and alteration of DC functions. GILZ stimulates the production of IL-10 by immature DCs and prevents the production of inflammatory chemokines by CD40L-activated DCs. In contrast, GILZ does not prevent CD40 ligand-mediated inhibition of phagocytosis, indicating that it affects some but not all aspects of DC maturation. GILZ prevents DCs from activating antigen-specific T lymphocyte responses. Administration of GCs to patients stimulates GILZ expression in their circulating antigen-presenting cells, and this contributes to the weak lymphocyte responses of GC-treated patients. Thus, regulation of GILZ expression is an important factor determining the decision of DCs whether or not to stimulate T lymphocytes, and IL-10, GCs, and TGFbeta share this mechanism for influencing DC functions and the balance between immune response and tolerance.

  16. Clinical Significance of Programmed Death Ligand‑1 and Intra-Tumoral CD8+ T Lymphocytes in Ovarian Carcinosarcoma

    PubMed Central

    Zhu, Jun; Wen, Hao; Ju, Xingzhu; Bi, Rui; Zuo, Wenjia; Wu, Xiaohua

    2017-01-01

    Ovarian carcinosarcoma (OCS) accounts for high mortality and lacks effective therapeutic methods. So far, we lack reliable biomarkers capable of predicting the risk of aggressive course of the disease. Programmed death ligand-1 (PD-L1) is expressed in various tumors, and antibodies targeting its receptor programmed cell death 1 (PD-1) are emerging cancer therapeutics. This study was designed to evaluate the expression of PD-L1 and intratumoral CD8+ T lymphocytes by immunohistochemistry from 19 OCS patients who underwent primary surgery at Fudan University Shanghai Cancer Center. The correlations between PD-L1 expression and CD8+ T lymphocytes as well as the patients’ clinicopathologic characteristics were integrated and statistically analyzed. PD-L1-positive expression was observed in 52.6% of intraepithelial tissues and 47.4% of mesenchymal tissues (p = 0.370). Meanwhile, intraepithelial and mesenchymal CD8+ T lymphocytes were positive in 36.8% and 84.2% of OCS, respectively (p = 0.628). A significantly negative correlation was found between mesenchymal CD8+ T lymphocytes and PD-L1 expression (r = -0.630, p = 0.011). Intraepithelial PD-L1-positive expression was associated only with positive ascitic fluid (p = 0.008). Mesenchymal PD-L1-positive patients had a poorer survival than those with negative expression (p = 0.036). Meanwhile, intraepithelial PD-L1-positive patients had a better survival trend than PD-L1-negative patients, though no statistical significance was found (p = 0.061). There was a better postoperative survival noted in mesenchymal CD8-positive patients (p = 0.024), and allthough a better trend of OS was observed in intraepithelial CD8-positive patients, no statistical significance was found (p = 0.382). Positive tumoral CD8+ T lymphocytes and mesenchymal PD-L1-negative expression seem to be associated with better survival in OCS. It is possible that immunotherapy targeting PD-L1 pathway could be used in OCS. PMID:28125702

  17. Activation of rat T lymphocytes by anti-CD2 monoclonal antibodies

    PubMed Central

    1988-01-01

    Rat T cells and thymocytes were induced to proliferate by a pair of mAbs, MRC OX-54 and MRC OX-55, directed against rat CD2. Accessory cells were required but their role was not simply for crosslinking of the two mAbs, as neither MRC OX-54 nor MRC OX-55 alone, in the presence of a crosslinking second antibody, caused T cell mitogenesis. Nor could the phorbol ester PMA replace either antibody. The two mAbs recognized distinct epitopes on rat CD2; however, MRC OX-54 could partially block MRC OX-55 binding whereas the reverse situation was not seen. A further CD2 epitope was recognized by two mutually competitive mAbs, MRC OX-34 and MRC OX-53, which were not mitogenic. Neither MRC OX-34 nor MRC OX- 53 affected the binding of MRC OX-54 or MRC OX-55, yet they prevented the mitogenic effect induced by these mAbs. The presence of mAbs against CD4 and the IL-2-R also abrogated this mitogenesis, whereas an anti-CD5 mAb augmented the CD2-induced proliferation. PMID:3133442

  18. HLA-DPB1*05: 01-restricted WT1332-specific TCR-transduced CD4+ T lymphocytes display a helper activity for WT1-specific CTL induction and a cytotoxicity against leukemia cells.

    PubMed

    Lin, Yuhung; Fujiki, Fumihiro; Katsuhara, Akiko; Oka, Yoshihiro; Tsuboi, Akihiro; Aoyama, Nao; Tanii, Satoe; Nakajima, Hiroko; Tatsumi, Naoya; Morimoto, Soyoko; Tamanaka, Taichi; Tachino, Sho; Hosen, Naoki; Nishida, Sumiyuki; Oji, Yusuke; Kumanogoh, Atsushi; Sugiyama, Haruo

    2013-04-01

    Wilms tumor gene 1 (WT1) is overexpressed in various malignant neoplasms, and has been demonstrated as an attractive target for cancer immunotherapy. We previously reported the identification of a WT1 protein-derived, 16-mer helper peptide WT1332 that could elicit Th1-type CD4+ T-cell response and bind to multiple HLA class II molecules. In this study, we examined the feasibility of adoptive therapy using CD4+ T cells that were transduced an HLA-DPB1*05:01-restricted, WT1332-specific T-cell receptor (TCR). HLA-DPB1*05:01-restricted, WT1332-specific TCR-transduced CD4+ T cells were successfully generated using lentiviral vector and exhibited strong proliferative response and Th1-type cytokine production in response to WT1332 peptide, WT1 protein, or WT1-expressing tumor cell lysate. Furthermore, the WT1332-specific TCR-transduced CD4+ T cells lysed HLA-DPB1*05:01-positive, WT1-expressing human leukemia cells through granzyme B/perforin pathway. Furthermore, stimulation of peripheral blood mononuclear cells with both HLA-A*24:02-restricted cytotoxic T lymphocytes-epitope peptide (modified 9-mer WT1235 peptide, WT1235m) and WT1332 helper peptide in the presence of WT1332-specific TCR-transduced CD4+ T cells strikingly enhanced the induction of WT1235m-specific cytotoxic T lymphocytes. Thus, these results demonstrated the feasibility of immunotherapy based on adoptive transfer of WT1332-specific TCR-transduced CD4+ T cells for the treatment of leukemia.

  19. Acute exercise mobilises CD8+ T lymphocytes exhibiting an effector-memory phenotype.

    PubMed

    Campbell, John P; Riddell, Natalie E; Burns, Victoria E; Turner, Mark; van Zanten, Jet J C S Veldhuijzen; Drayson, Mark T; Bosch, Jos A

    2009-08-01

    An acute bout of exercise evokes mobilisation of lymphocytes into the bloodstream, which can be largely attributed to increases in CD8+ T lymphocytes (CD8TLs) and natural killer (NK) cells. Evidence further suggests that, even within these lymphocyte subsets, there is preferential mobilisation of cells that share certain functional and phenotypic characteristics, such as high cytotoxicity, low proliferative ability, and high tissue-migrating potential. These features are characteristic of effector-memory CD8TL subsets. The current study therefore investigated the effect of exercise on these newly-identified subsets. Thirteen healthy and physically active males (mean+/-SD: age 20.9+/-1.5 yr) attended three sessions: a control session (no exercise); cycling at 35% Watt(max) (low intensity exercise); and 85% Watt(max) (high intensity exercise). Each bout lasted 20 min. Blood samples were obtained before exercise, during the final min of exercise, and +15, and +60 min post-exercise. CD8TLs were classified into naïve, central memory (CM), effector-memory (EM), and CD45RA+ effector-memory (RAEM) using combinations of the cell surface markers CCR7, CD27, CD62L, CD57, and CD45RA. In parallel, the phenotypically distinct CD56(bright) 'regulatory' and CD56(dim) 'cytotoxic' NK subsets were quantified. The results show a strong differential mobilisation of CD8TL subsets (RAEM>EM>CM>naïve); during high intensity exercise the greatest increase was observed for RAEM CD8Tls (+450%) and the smallest for naïve cells (+84%). Similarly, CD56(dim) NK cells (+995%) were mobilised to a greater extent than CD56(bright) (+153%) NK cells. In conclusion, memory CD8TL that exhibit a high effector and tissue-migrating potential are preferentially mobilised during exercise. This finding unifies a range of independent observations regarding exercise-induced phenotypic and functional changes in circulating lymphocytes. The selective mobilisation of cytotoxic tissue-migrating subsets, both

  20. Anchorage and lymphocyte function. Spreading-capacity distinguishes common thymocytes and peripheral T lymphocytes.

    PubMed Central

    Otteskog, P; Sundqvist, K G

    1983-01-01

    Contact of T-enriched human blood lymphocytes with an adhesive surface in the presence of Concanavalin A (Con A) almost immediately induced a sequence of motile changes in virtually all cells. The initial event in this spreading process was the formation of filopodia distinct from the microvilli of lymphocytes in suspension. The filopodia were accompanied by lamellipodia, ruffles and flattening of the nucleus. Contact with a nonadhesive substratum in the presence of Con A did not trigger this sequence of changes. Cytochalasin B and D or low temperature inhibited the contact-induced changes. With the exception of a small number of cells (5-15%), T-enriched lymphocytes that were allowed to settle in the absence of Con A showed a radius of action (area occupied by the cells/translational movement per hr) of 39 micrometers 2/ less than 1 micrometer. The small 'motile' population showed a radius of action of 74 micrometers 2/8 micrometers. The Con-A-mediated spreading-process yielded a radius of action of the lymphocytes of 117 micrometers 2/6 micrometers. This augmented radius of action markedly facilitated cell-cell interaction in a high frequency of the cells and appeared to be a prerequisite for such interactions at 'low' cell density. Thymocytes reactive with OKT 6 antibodies or belonging to the 'high-density' fraction of cells attached to a Con-A-coated surface to the same extent as peripheral OKT 3 positive lymphocytes, but did not exhibit the morphological changes characteristic of a spreading-process. In contrast, OKT 6 negative thymocytes or thymocytes with a relatively low density showed spreading indistinguishable from that of OKT 3 positive peripheral lymphocytes. These results characterize the spreading-process in human T lymphocytes and demonstrate its functional importance for interactions with the environment. Spreading-capacity appears to reflect the stage of maturation of T cells. Images Figure 1 Figure 2 Figure 3 Figure 4b Figure 4c Figure 7 PMID

  1. Protection against Acute Hepatocellular Injury Afforded by Liver Fibrosis Is Independent of T Lymphocytes

    PubMed Central

    Lacoste, Benoit; Raymond, Valérie-Ann; Lapierre, Pascal; Bilodeau, Marc

    2016-01-01

    Collagen produced during the process of liver fibrosis can induce a hepatocellular protective response through ERK1 signalling. However, the influence of T cells and associated cytokine production on this protection is unknown. In addition, athymic mice are frequently used in hepatocellular carcinoma xenograft experiments but current methods limit our ability to study the impact of liver fibrosis in this setting due to high mortality. Therefore, a mouse model of liver fibrosis lacking T cells was developed using Foxn1 nu/nu mice and progressive oral administration of thioacetamide (TAA) [0.01–0.02%] in drinking water. Fibrosis developed over a period of 16 weeks (alpha-SMA positive area: 20.0 ± 2.2%, preCol1a1 mRNA expression: 11.7 ± 4.1 fold changes, hydroxyproline content: 1041.2 ± 77μg/g of liver) at levels comparable to that of BALB/c mice that received intraperitoneal TAA injections [200 μg/g of body weight (bw)] (alpha-SMA positive area: 20.9 ± 2.9%, preCol1a1 mRNA expression: 13.1 ± 2.3 fold changes, hydroxyproline content: 931.6 ± 14.8μg/g of liver). No mortality was observed. Athymic mice showed phosphorylation of ERK1/2 during fibrogenesis (control 0.03 ± 0.01 vs 16 weeks 0.22 ± 0.06AU; P<0.05). The fibrosis-induced hepatoprotection against cytotoxic agents, as assessed histologically and by serum AST levels, was not affected by the absence of circulating T cells (anti-Fas JO2 [0.5μg/g bw] for 6h (fibrotic 4665 ± 2596 vs non-fibrotic 13953 ± 2260 U/L; P<0.05), APAP [750 mg/kg bw] for 6 hours (fibrotic 292 ± 66 U/L vs non-fibrotic 4086 ± 2205; P<0.01) and CCl4 [0.5mL/Kg bw] for 24h (fibrotic 888 ± 268 vs non-fibrotic 15673 ± 2782 U/L; P<0.001)). In conclusion, liver fibrosis can be induced in athymic Foxn1 nu/nu mice without early mortality. Liver fibrosis leads to ERK1/2 phosphorylation. Finally, circulating T lymphocytes and associated cytokines are not involved in the hepatocellular protection afforded by liver fibrosis. PMID

  2. Dendritic cells are accessory cells for the development of anti- trinitrophenyl cytotoxic T lymphocytes

    PubMed Central

    1980-01-01

    This study establishes that dendritic cells (DC) are the critical accessory cells for the development of anti-trinitrophenol (TNP) cytotoxic T lymphocytes (CTL) in vitro. We developed a model in which nylon wool-nonadherent spleen cells were used both as the responding and stimulating cells, the latter having been TNP-modified and x- irradiated. Thy-1-bearing CTL developed in C57BL/6, B6D2F1, and CBA mice only when small numbers of DC were added. Maximal responses in 5-d cultures were achieved with 0.5-1 DC/100 responding T cells. The DC did not have to be TNP modified directly. Anti-Ia and complement inactivated accessory cells, whereas similar treatment of the responders had no effect. DC exposed to ultraviolet radiation were ineffective, but x-irradiated DC were fully active. Culture media from DC, or from DC-nylon wool-passed spleen T cell cocultures that contained abundant CTL, would not substitute for viable DC. Enriched preparations of macrophages (M phi) were obtained from blood, peritoneal cavity, and spleens of BCG-immune and unprimed mice. M phi added at doses of 0.2-4% were weak or inactive as accessory cells. The level of Ia antigens on test M phi populations was quantitated and visualized by binding of a radioiodinated monoclonal anti-I-Ab,d antibody, clone B-21. M phi that bore substantial amounts of Ia from all organs were weak accessory cells. Addition of M phi to DC-T cell cocultures produced inhibitory effects, usually at a dose of 2% M phi. In contrast, 0.5% Ia-bearing M phi from BCG-immune boosted mice inhibited > 80% of the DC-mediated CTL response. Addition of indomethacin reversed M phi inhibition, and 10(-9) M prostaglandin E2 in turn blocked the indomethacin effect. Indomethacin also restored a low level of accessory cell function in immune-boosted adherent peritoneal cells, but not in preparations of monocytes and spleen M phi. Small numbers of DC were identified in preparations of immune- boosted peritoneal cells and may have accounted

  3. CD8+ T lymphocytes in lung tissue from patients with idiopathic pulmonary fibrosis

    PubMed Central

    Daniil, Zoe; Kitsanta, Panagiota; Kapotsis, George; Mathioudaki, Maria; Kollintza, Androniki; Karatza, Marilena; Milic-Emili, Joseph; Roussos, Charis; Papiris, Spyros A

    2005-01-01

    Background Several studies have implicated a role of inflammation in the pathogenesis of lung damage in idiopathic pulmonary fibrosis (IPF). Parenchymal lung damage leads to defects in mechanics and gas exchange and clinically manifests with exertional dyspnea. Investigations of inflammatory cells in IPF have shown that eosinophils, neutrophils and CD8+ TLs may be associated with worse prognosis. We wished to investigate by quantitative immunohistochemistry infiltrating macrophages, neutrophils and T lymphocytes (TLs) subpopulations (CD3+, CD4+ and CD8+) in lung tissue of patients with IPF and their correlation with lung function indices and grade of dyspnoea. Methods Surgical biopsies of 12 patients with IPF were immunohistochemically stained with mouse monoclonal antibodies (anti-CD68 for macrophages, anti-elastase for neutrophils, and anti-CD3, anti-CD4, anti-CD8 for CD3+TLs, CD4+TLs, and CD8+TLs respectively). The number of positively stained cells was determined by observer-interactive computerized image analysis (SAMBA microscopic image processor). Cell numbers were expressed in percentage of immunopositive nuclear surface in relation to the total nuclear surface of infiltrative cells within the tissue (labeling Index). Correlations were performed between cell numbers and physiological indices [FEV1, FVC, TLC, DLCO, PaO2, PaCO2 and P(A-a)O2)] as well as dyspnoea scores assessed by the Medical Research Council (MRC) scale. Results Elastase positive cells accounted for the 7.04% ± 1.1 of total cells, CD68+ cells for the 16.6% ± 2, CD3+ TLs for the 28.8% ± 7, CD4+ TLs for the 14.5 ± 4 and CD8+ TLs for the 13.8 ± 4. CD8+TLs correlated inversely with FVC % predicted (rs = -0.67, p = 0.01), TLC % predicted (rs = -0.68, p = 0.01), DLCO % predicted (rs = -0.61, p = 0.04), and PaO2 (rs = -0.60, p = 0.04). Positive correlations were found between CD8+TLs and P(A-a)O2 (rs = 0.65, p = 0.02) and CD8+TLs and MRC score (rs = 0.63, p = 0.02). Additionally, CD68+ cells

  4. Laboratory control values for CD4 and CD8 T lymphocytes. Implications for HIV-1 diagnosis.

    PubMed Central

    Bofill, M; Janossy, G; Lee, C A; MacDonald-Burns, D; Phillips, A N; Sabin, C; Timms, A; Johnson, M A; Kernoff, P B

    1992-01-01

    With the advent of standard flow cytometric methods using two-colour fluorescence on samples of whole blood, it is possible to establish the ranges of CD3, CD4 and CD8 T lymphocyte subsets in the routine laboratory, and also to assist the definition of HIV-1-related deviations from these normal values. In 676 HIV-1-seronegative individuals the lymphocyte subset percentages and absolute counts were determined. The samples taken mostly in the morning. The groups included heterosexual controls, people with various clotting disorders but without lymphocyte abnormalities as well as seronegative homosexual men as the appropriate controls for the HIV-1-infected groups. The stability of CD4% and CD8% values was demonstrated throughout life, and in children CD4 values less than 25% could be regarded as abnormal. The absolute counts of all T cell subsets decreased from birth until the age of 10 years. In adolescents and adults the absolute numbers (mean +/- s.d.) of lymphocytes, CD3, CD4 and CD8 cells were 1.90 +/- 0.55, 1.45 +/- 0.46, 0.83 +/- 0.29 and 0.56 +/- 0.23 x 10(9)/l, respectively. In patients with haemophilia A and B the mean values did not differ significantly. In homosexual men higher CD8 levels were seen compared with heterosexual men and 27% had an inverted CD4/CD8 ratio but mostly without CD4 lymphopenia (CD4 less than 0.4 x 10(9)/l). However, some healthy uninfected people were 'physiologically' lymphopenic without having inverted CD4/CD8 ratios. When the variations 'within persons' were studied longitudinally over a 5-year period, the absolute CD4 counts tended to be fixed at different levels. As a marked contrast, over 60% of asymptomatic HIV-1+ patients exhibited low CD4 counts less than 0.4 x 10(9)/l together with inverted CD4/CD8 ratios. Such combined changes among the heterosexual and HIV-1-seronegative homosexual groups were as rare as 1.4% and 3%, respectively. For this reason, when the lymphocyte tests show less than 0.4 x 10(9)/l CD4 count and a CD

  5. Leishmania infantum antigens modulate memory cell subsets of liver resident T lymphocyte.

    PubMed

    Rodrigues, A; Claro, M; Alexandre-Pires, G; Santos-Mateus, D; Martins, C; Valério-Bolas, A; Rafael-Fernandes, M; Pereira, M A; Pereira da Fonseca, I; Tomás, A M; Santos-Gomes, G

    2017-02-01

    In the recent years, the liver has been recognized as an important immune organ with major regulatory functions and immune memory, adding to the well-described vital metabolic functions. There are evidences from experimental infections performed with visceral Leishmania species that immune responses to parasite infection can be organ-specific. The liver is the compartment of acute resolving infection, with minimal tissue damage and resistance to reinfection, whereas the spleen is the compartment of parasite persistence. Control of hepatic infection in mice requires a coordinated immune response that involves the development of inflammatory granulomas. It is also described that the liver harbors populations of resident lymphocytes, which may exhibit memory characteristics. Therefore, the present study aims to address the role of the liver as an immune memory organ in the context of Leishmania infantum infection, by characterizing phenotypically resident liver T lymphocytes. The dynamics of memory T cells in L. infantum infected BALB/c mice and the effect of anti-leishmanial treatment in the differentiation of memory cell subsets were analyzed. The potential of recognition, differentiation and selection of memory lymphocytes by three L. infantum recombinant proteins were also explored. L. infantum infection generates effector and central memory T cells, but the cells did not expand when recalled, demonstrating a possible parasite silencing effect. The treatment with a leishmanicidal drug (antimoniate meglumine) increases the levels of memory and effector T cells, eliciting a more robust hepatic immune response. L. infantum parasites with a decreased sensitivity to the leishmanicidal drug favor the expansion of memory CD8(+) T cell subset, but inhibit the proliferation of CD8(+) T effector cells, possibly assuring their own survival. The recombinant proteins LirCyp1 and LirSOD are strongly recognized by memory cells of treated mice, indicating that these proteins

  6. DEFICIENCY OF γδ T-LYMPHOCYTES CONTRIBUTES TO MORTALITY AND IMMUNOSUPPRESSION IN SEPSIS

    PubMed Central

    Chung, Chun-Shiang; Watkins, Lara; Funches, Antonio; Lomas-Neira, Joanne; Cioffi, William G.; Ayala., Alfred

    2006-01-01

    Studies have indicated that γδ T-lymphocytes play an important role in the regulation of immune function and the clearance of intracellular pathogens. We have recently reported that intraepithelial lymphocytes (IEL), which is rich in γδ T-cells, within the small intestine illustrated a significant increase in apoptosis and immune dysfunction in mice subjected to sepsis. However, the contribution of γδ T-cells to the host response to polymicrobial sepsis remains unclear. In this study, we initially observed that following sepsis induced by cecal ligation and puncture (CLP) there was an increase in small intestinal IEL CD8+-γδ+ T-cells in control γδ +/+ mice. Importantly, we subsequently found an increased early mortality in mice lacking γδ T-cells (γδ −/−) after sepsis. This was associated with a decrease in plasma TNF-α, IL-6 and IL-12 levels in γδ −/− mice compared to γδ +/+ mice after sepsis. In addition, even though in vitro LPS-stimulated peritoneal macrophages showed a reduction in IL-6 and IL-12 release after CLP, these cytokines were less suppressed in macrophages isolated from γδ −/− mice. Alternatively, IL-10 release was not different between septic γδ +/+ and γδ −/− mice. While Th1 cytokine release by anti-CD3-stimulated splenocytes was significantly depressed in septic γδ +/+ mice, there was no such depression in γδ −/− mice. However, γδ T-cell deficiency had no effect on Th2 cytokine release. These findings suggest that γδ T-cells may play a critical role in regulating the host immune response and survival to sepsis, in part by alteration of the level of IEL CD8+-γδ+ T-cells and through the development of Th1 response. PMID:16793935

  7. A multi-epitope vaccine based on Chlamydia trachomatis major outer membrane protein induces specific immunity in mice.

    PubMed

    Tu, Jianxin; Hou, Bailong; Wang, Bingbing; Lin, Xiaoyun; Gong, Wenci; Dong, Haiyan; Zhu, Shanli; Chen, Shao; Xue, Xiangyang; Zhao, Kong-Nan; Zhang, Lifang

    2014-05-01

    We evaluated the immunogenicity and efficacy of a candidate vaccine comprising the major outer membrane protein (MOMP) multi-epitope of Chlamydia trachomatis. A short gene of multi-epitope derived from MOMP containing multiple T- and B-cell epitopes was artificially synthesized. The recombinant plasmid pET32a(+) containing codon optimized MOMP multi-epitope gene was constructed. Expression of the fusion protein Trx-His-MOMP multi-epitope in Escherichia coli was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and western blot analysis. Balb/c mice were inoculated with the purified fusion protein subcutaneously three times with 2-week intervals. Results showed that the MOMP multi-epitope elicited not only strong humoral immune responses to C. trachomatis by generating significantly high levels of specific antibodies (IgG1 and IgG2a), but also a cellular immune response by inducing robust cytotoxic T lymphocyte responses in mice. Furthermore, the MOMP multi-epitope substantially primed secretion of IFN-γ, revealing that this vaccine could induce a strong Th1 response. Finally, the mice vaccinated with the MOMP multi-epitope displayed a reduction of C. trachomatis shedding upon a chlamydial challenge and an accelerated clearance of the infected C. trachomatis. In conclusion, the MOMP multi-epitope vaccine may have the potentiality for the development of effective prophylactic and therapeutic vaccines against the C. trachomatis infection.

  8. Production of a novel multi-epitope peptide vaccine for cancer immunotherapy in TC-1 tumor-bearing mice.

    PubMed

    Nezafat, Navid; Sadraeian, Mohammad; Rahbar, Mohammad Reza; Khoshnoud, Mohammad Javad; Mohkam, Milad; Gholami, Ahmad; Banihashemi, Mehrzad; Ghasemi, Younes

    2015-01-01

    In our previous research, several bioinformatic strategies were utilized to design an efficient multi-epitope peptide vaccine (MEV) against cancer. The designed vaccine consists of Wilms tumor-1 (WT-1) and human papillomavirus (HPV) E7 cytotoxic T lymphocyte (CTL) epitopes, tetanus toxin fragment C (TTFrC) and HLA-DR epitope (PADRE) helper T lymphocyte (HTL) epitopes and heparin-binding hemagglutinin (HBHA) as an immunostimulatory adjuvant. All segments were fused together by suitable linkers. In the current study, we cloned and expressed the designed MEV in E. coli. We subsequently performed in vivo preventative and therapeutic assays to evaluate antitumor efficacy of the vaccine against the HPV-16 E7-expressing murine tumor cell line TC-1 as a model for cancer immunotherapy. The results showed that in preventive experiments, vaccination with MEV significantly augmented the IgG antibody titer and the percentage of tumor-free mice compared to control groups (PBS and E7). Moreover, in therapeutic experiments, vaccination with MEV led to a reduction in the number of metastatic nodules, lung weights and the ratio of lung weights to body weights compared to other groups. In sum, our epitope vaccine could efficiently induce preventive and therapeutic antitumor immunity in TC-1 tumor bearing mice.

  9. Accumulation of Pol Mutations Selected by HLA-B*52:01-C*12:02 Protective Haplotype-Restricted Cytotoxic T Lymphocytes Causes Low Plasma Viral Load Due to Low Viral Fitness of Mutant Viruses.

    PubMed

    Murakoshi, Hayato; Koyanagi, Madoka; Chikata, Takayuki; Rahman, Mohammad Arif; Kuse, Nozomi; Sakai, Keiko; Gatanaga, Hiroyuki; Oka, Shinichi; Takiguchi, Masafumi

    2017-02-15

    HLA-B*52:01-C*12:02, which is the most abundant haplotype in Japan, has a protective effect on disease progression in HIV-1-infected Japanese individuals, whereas HLA-B*57 and -B*27 protective alleles are very rare in Japan. A previous study on HLA-associated polymorphisms demonstrated that the number of HLA-B*52:01-associated mutations at four Pol positions was inversely correlated with plasma viral load (pVL) in HLA-B*52:01-negative individuals, suggesting that the transmission of HIV-1 with these mutations could modulate the pVL in the population. However, it remains unknown whether these mutations were selected by HLA-B*52:01-restricted CTLs and also reduced viral fitness. In this study, we identified two HLA-B*52:01-restricted and one HLA-C*12:02-restricted novel cytotoxic T-lymphocyte (CTL) epitopes in Pol. Analysis using CTLs specific for these three epitopes demonstrated that these CTLs failed to recognize mutant epitopes or more weakly recognized cells infected with mutant viruses than wild-type virus, supporting the idea that these mutations were selected by the HLA-B*52:01- or HLA-C*12:02-restricted T cells. We further showed that these mutations reduced viral fitness, although the effect of each mutation was weak. The present study demonstrated that the accumulation of these Pol mutations selected by HLA-B*52:01- or HLA-C*12:02-restricted CTLs impaired viral replication capacity and thus reduced the pVL. The fitness cost imposed by the mutations partially accounted for the effect of the HLA-B*52:01-C*12:02 haplotype on clinical outcome, together with the effect of HLA-B*52:01-restricted CTLs on viral replication, which had been previously demonstrated.

  10. A synthetic multi-epitope antigen enhances hepatitis C virus-specific B- and T-cell responses.

    PubMed

    Yang, Guimei; Chen, Shuwen; Zhu, Xiangying; Liang, Shenghua; Liu, Longding; Ren, Daming

    2011-04-01

    Combining results from previous studies, a multi-epitope antigen PCXZ against the hepatitis C virus was synthesized in this study. The antigenic specificity of PCXZ was determined by recognizing antibodies in serum samples from hepatitis C virus patients, but not from healthy subjects or subjects who had the hepatitis B virus. The characteristics of PCXZ immunogenicity were evaluated in BALB/c mice. Strong antibody responses were generated in mice immunized with either naked PCXZ or PCXZ in Freund's adjuvant. As for the T-cell responses, Freund's adjuvant significantly increased interferon-γ secretion and enhanced the lytic activity of cytotoxic T lymphocytes. The epitope Pa, one component of PCXZ, made the most significant contribution to specific CTL lysis; this epitope was also a B-cell epitope and was able to induce high IgG titers. In summary, PCXZ was found to be highly immunogenic, and elicited both humoral and cellular immune responses in mice.

  11. FcRgamma chain does not replace CD3zeta chain in CD3zeta-deficient T lymphocytes of patients with gastric adenocarcinoma.

    PubMed

    Lopez-Santalla, Mercedes; Krishnan, Sandeep; Valeri, Anna P; Aguilera-Montilla, Noemi; Fisher, Carolyn U; Perez-Blas, Mercedes; Gutierrez-Calvo, Alberto; Lasa, Inmaculada; Granell-Vicent, Javier; Tsokos, George C; Martin-Villa, José M

    2007-03-01

    Defective CD3zeta chain expression has been reported in T lymphocytes of patients with inflammatory diseases, such as systemic lupus erythematosus or osteoarthritis, and with cancer. In lupus, the absent CD3zeta chain is replaced by the FcRgamma chain, rendering the T cells hyper responsive. However, there are no data on T lymphocytes from patients with cancer. In this study, the presence of the FcRgamma chain and its associated kinase, Syk, was analysed in patients with gastric adenocarcinoma and healthy subjects. Western blot and immunoprecipitation experiments were carried out with total cell or lipid raft extracts from fresh peripheral blood mononuclear cells or T lymphocytes, and Herpesvirus saimiri-derived T-cell lines (of blood or tissue origin). Our results revealed that the absent CD3zeta chain in cancer T lymphocytes was not replaced by FcRgamma either in fresh T cells or T-cell lines, in contrast to lupus T cells. This altered expression of signalling molecules in T lymphocytes of cancer patients, would explain their low proliferative capacity. Our T-cell lines represent tools to unveil the signalling abnormalities of cancer T lymphocytes.

  12. Human cytotoxic T-lymphocyte membrane-camouflaged nanoparticles combined with low-dose irradiation: a new approach to enhance drug targeting in gastric cancer

    PubMed Central

    Zhang, Lianru; Li, Rutian; Chen, Hong; Wei, Jia; Qian, Hanqing; Su, Shu; Shao, Jie; Wang, Lifeng; Qian, Xiaoping; Liu, Baorui

    2017-01-01

    Cell membrane-derived nanoparticles are becoming more attractive because of their ability to mimic many features of their source cells. This study reports on a biomimetic delivery platform based on human cytotoxic T-lymphocyte membranes. In this system, the surface of poly-lactic-co-glycolic acid nanoparticles was camouflaged using T-lymphocyte membranes, and local low-dose irradiation (LDI) was used as a chemoattractant for nanoparticle targeting. The T-lymphocyte membrane coating was verified using dynamic light scattering, transmission electron microscopy, and confocal laser scanning microscopy. This new platform reduced nanoparticle phagocytosis by macrophages to 23.99% (P=0.002). Systemic administration of paclitaxel-loaded T-lymphocyte membrane-coated nanoparticles inhibited the growth of human gastric cancer by 56.68% in Balb/c nude mice. Application of LDI at the tumor site significantly increased the tumor growth inhibition rate to 88.50%, and two mice achieved complete remission. Furthermore, LDI could upregulate the expression of adhesion molecules in tumor vessels, which is important in the process of leukocyte adhesion and might contribute to the localization of T-lymphocyte membrane-encapsulated nanoparticles in tumors. Therefore, this new drug-delivery platform retained both the long circulation time and tumor site accumulation ability of human cytotoxic T lymphocytes, while local LDI could significantly enhance tumor localization. PMID:28360520

  13. Staphylococcus aureus infection induced redox signaling and DNA fragmentation in T-lymphocytes: possible ameliorative role of nanoconjugated vancomycin.

    PubMed

    Chakraborty, Subhankari Prasad; Das, Sabyasachi; Chattopadhyay, Sourav; Tripathy, Satyajit; Dash, Sandeep Kumar; Pramanik, Panchanan; Roy, Somenath

    2012-04-01

    Staphylococcus aureus is most frequently isolated pathogen causing bloodstream infections, skin and soft tissue infections and pneumonia. Vancomycin sensitive and resistant S. aureus infection causes oxidative stress in neutrophils and lymphocytes. Lymphocyte is an important immune cell. The immune cells use reactive oxygen species (ROS) for carrying out their normal functions while an excess amount of ROS can attack cellular components that lead to cell damage. The aim of the present study was to test the protective role of nanoconjugated vancomycin against Vancomycin Sensitive S. aureus (VSSA) and Vancomycin Resistant S. aureus (VRSA) infection induced oxidative stress in T-lymphocytes. VSSA and VRSA infection were developed in Swiss mice by intraperitoneal injection of 5 × 10(6) CFU/ml bacterial solutions. Nanoconjugated vancomycin was treated to VSSA and VRSA infected mice at a dose of 100 mg/kg bw/day and 500 mg/kg bw/day, respectively for successive 10 days. Vancomycin was treated to VSSA and VRSA infected mice at similar dose, respectively, for 10 days. The result of this study reveals that in vivo VSSA and VRSA infection significantly increases the level of nitrite generation, lipid peroxidation, protein oxidation, oxidized glutathione level, DNA fragmentation, and decreases the level of reduced glutathione, antioxidant enzyme status, glutathione dependent enzymes as compared to control group; which were increased or decreased significantly near to normal in T-lymphocytes of nanoconjugated vancomycin treated group. These finding suggests the potential use and beneficial protective role of nanoconjugated vancomycin against VSSA and VRSA infection induced oxidative stress in T-lymphocytes.

  14. Hepatocytes can serve as accessory cells in the response of immune T lymphocytes to heat-killed Listeria monocytogenes.

    PubMed Central

    Jiang, X; Gregory, S H; Wing, E J

    1995-01-01

    Previous findings in our laboratory indicated that the bulk of Listeria monocytogenes injected intravenously into mice and recovered in the liver is taken up and replicates within hepatocytes. Other investigators have shown that hepatocytes can display costimulatory adhesion molecules, express major histocompatibility complex class I and II molecules, and secrete a number of cytokines, including interleukin-1 (IL-1), IL-6, and IL-8. These data suggest that hepatocytes may serve as accessory cells in the immune response to L. monocytogenes. The accessory function and capacity of hepatocytes to present listerial antigens, however, have never been explored. We undertook a series of experiments to examine the response of Listeria-immune T lymphocytes to murine hepatocytes preincubated with heat-killed listeriae (HKL). Electron micrographs showing the organism within membrane-limiting vacuoles demonstrated the capacity of hepatocytes to internalize HKL. T cells cocultured with hepatocytes pulsed with HKL exhibited a 5- to 10-fold increase in [methyl-3H]thymidine incorporation relative to T cells cultured with either hepatocytes or HKL alone. Similarly, gamma interferon production by immune T cells was elevated significantly in cultures that contained both hepatocytes and HKL. The optimal response of T cells required lysosomal processing of HKL by hepatocytes and contact between the two cell populations. Furthermore, maximum T-cell proliferation and gamma interferon production were dependent upon the presence of CD4+ T lymphocytes and the expression of Ia antigens. Taken together, these findings demonstrate that hepatocytes pulsed with HKL can stimulate the antigen-specific response of immune T lymphocytes. These results suggest that hepatocytes can serve as accessory cells in host defenses to listerial infections of the liver. PMID:7868265

  15. Disruption of circulating CD4+ T-lymphocyte subpopulations in psoriasis patients is ameliorated by narrow-band UVB therapy.

    PubMed

    Wang, Xiuxiu; Wang, Guanghua; Gong, Yu; Liu, Yeqiang; Gu, Junying; Chen, Wenjuan; Shi, Yuling

    2015-01-01

    Narrow-band UVB (NB-UVB) therapy is widely used in the treatment of psoriasis; however, its precise mechanism is still unclear. To investigate the circulating CD4(+) T-lymphocyte subpopulations in psoriasis patients before and after NB-UVB, thus providing new insights into the mechanism of NB-UVB in the treatment of psoriasis. We performed NB-UVB treatments for psoriasis patients (n = 30) and used flow cytometry, real-time PCR, and ELISA for the detection of circulating CD4(+) T-lymphocyte subpopulations. The results were compared with healthy controls (n = 20) as well. We found increased circulating T helper 1 (Th1) and Th17 cell levels as well as decreased circulating regulatory T cells (Treg) levels compared to healthy controls. Additionally, there was a positive correlation between the percentage of circulating Th17 cells and Psoriasis Area and Severity Index (PASI) score. Furthermore, the percentage of circulating Th17 cells was negatively correlated with the Treg cells which led to an imbalance of Th17/Treg. NB-UVB therapy significantly reduced circulating Th1and Th17 cell levels while increasing Treg cell levels. These findings indicate that the overexpression of Th1 and Th17 cells together with the imbalance of Th17/Treg cells may play an important role in the pathogenesis of psoriasis. The mechanism of NB-UVB in the treatment of psoriasis may be through the inhibition of Th1 and Th17 cell immune response as well as the promotion of Treg cell immune response, thus ameliorating the disorder of circulating CD4(+) T-lymphocyte subsets.

  16. Analysis of the relationship between peripheral blood T lymphocyte subsets and HCV RNA levels in patients with chronic hepatitis C.

    PubMed

    Huang, Y; Zheng, M J; Xu, Y H

    2015-08-21

    We investigated the relationship between peripheral blood T lymphocyte subsets and hepatitis C virus (HCV) RNA levels in patients with hepatitis C. Samples from 69 chronic hepatitis C (CHC) patients and 20 healthy controls were analyzed using quantitative polymerase chain reaction (PCR) to detect HCV RNA and flow cytometry to determine the expression levels of CD3, CD4, and CD8 in lymphocytes. The percentage of CD4+ T cells (42.87 ± 6.11%) and the ratio of CD4+/CD8+ (1.34 ± 0.25) in these patients were significantly lower than those in the healthy control group (49.55 ± 6.68%, 1.82 ± 0.11, respectively) (P < 0.01, P < 0.01), while the percentage of CD8+ T cells (32.78 ± 5.48%) was higher than that in the control group (27.35 ± 4.32%) (P < 0.01). There was no significant difference in the percentage of CD3+ T cells between the two groups (P > 0.05). With the increase in HCV RNA replication, the percentage of CD8+ T cells increased gradually, while the CD4+ T cell percentage and CD4/CD8 ratio decreased. The change in the percentage of T lymphocyte subsets may be one of the reasons for persistent HCV infection, and the high expression levels of HCV RNA might be the reason for the low frequency of CD4+ T lymphocytes in patients with chronic HCV.

  17. T-Lymphocyte Deficiency Exacerbates Behavioral Deficits in the 6-OHDA Unilateral Lesion Rat Model for Parkinson’s Disease

    PubMed Central

    Wheeler, Christopher J; Seksenyan, Akop; Koronyo, Yosef; Rentsendorj, Altan; Sarayba, Danielle; Wu, Henry; Gragg, Ashley; Siegel, Emily; Thomas, Deborah; Espinosa, Andres; Thompson, Kerry; Black, Keith; Koronyo-Hamaoui, Maya; Pechnick, Robert; Irvin, Dwain K

    2014-01-01

    T-lymphocytes have been previously implicated in protecting dopaminergic neurons in the substantianigra from induced cell death. However, the role of T-cells in neurodegenerative models such as Parkinson’s disease (PD) has not been fully elucidated. To examine the role of T-lymphocytes on motor behavior in the 6-hydroxydopamine (6-OHDA) unilateral striatal partial lesion PD rat model, we assessed progression of hemi-parkinsonian lesions in the substantia nigra, induced by 6-OHDA striatal injections, in athymic rats (RNU−/−, T-lymphocyte-deficient) as compared to RNU−/+ rats (phenotypically normal). Motor skills were determined by the cylinder and D-amphetamine sulfate-induced rotational behavioral tests. Cylinder behavioral test showed no significant difference between unilaterally lesioned RNU−/− and RNU−/+ rats. However both unilaterally lesioned RNU−/− and RNU−/+ rats favored the use of the limb ipsilateral to lesion. Additionally, amphetamine-induced rotational test revealed greater rotational asymmetry in RNU−/− rats compared to RNU−/+ rats at two- and six-week post-lesion. Quantitative immunohistochemistry confirmed loss of striatal TH-immunopositive fibers in RNU−/− and RNU−/+ rat, as well as blood-brain-barrier changes associated with PD that may influence passage of immune cells into the central nervous system in RNU−/− brains. Specifically, GFAP immunopositive cells were decreased, as were astrocytic end-feet (AQP4) contacting blood vessels (laminin) in the lesioned relative to contralateral striatum. Flow cytometric analysis in 6-OHDA lesioned RNU−/+rats revealed increased CD4+ and decreased CD8+ T cells specifically within lesioned brain. These results suggest that both major T cell subpopulations are significantly and reciprocally altered following 6-OHDA-lesioning, and that global T cell deficiency exacerbates motor behavioral defects in this rat model of PD. PMID:25346865

  18. Effects of Canarium odontophyllum leaves on plasma glucose and T lymphocyte population in streptozotocin-induced diabetic rats.

    PubMed

    Saari, Shafikha Mohd; Basri, Dayang Fredalina; Budin, Siti Balkis; Warif, Nor Malia Abd

    2017-02-01

    Type 1 diabetes mellitus is a chronic disease characterized by lack of insulin production. Immune mechanisms are implicated in the pathogenesis of Type 1 diabetes. Canarium odontophyllum (CO) fruits and leaves have been shown to possess high antioxidant activity. This study was conducted to evaluate the effects of CO leaves aqueous extract on the blood glucose and T lymphocyte population in the spleen of streptozotocin (STZ)-induced diabetic rats. Nineteen male Sprague-Dawley rats were randomly divided into three groups: normal, diabetic control and CO treated diabetic groups. Diabetes was induced by a single intraperitoneal injection of 65 mg STZ/kg body weight. The extract of CO leaves was administered orally by force feeding daily at the dose of 300 mg/kg for 28 days. The rats were sacrificed at the end of the study and the spleen was harvested for flow cytometry analysis. The results showed a significant decrease in body weight of diabetic and CO treated diabetic groups compared with the normal group (p < 0.05). The fasting blood glucose level of CO treated diabetic group was significantly lower than the diabetic group (p < 0.05). Diabetic and CO treated diabetic groups showed a significant increase in the percentage of spleen CD3(+) CD4(+) T lymphocytes (p < 0.05) when compared with the normal group. However, there was no significant difference in the percentage of spleen CD3(+) CD8(+) T lymphocytes among all experimental groups. The finding suggested that an aqueous extract of CO leaves has the ability to reduce blood glucose levels in diabetic rats.

  19. Regulation of T lymphocyte apoptotic markers is associated to cell activation during the acute phase of dengue.

    PubMed

    Torrentes-Carvalho, Amanda; Marinho, Cintia Ferreira; de Oliveira-Pinto, Luzia Maria; de Oliveira, Débora Batista; Damasco, Paulo Vieira; Cunha, Rivaldo Venâncio; de Souza, Luiz José; de Azeredo, Elzinandes Leal; Kubelka, Claire Fernandes

    2014-05-01

    Dengue fever, a public health problem in Brazil, may present severe clinical manifestations as result of an increased vascular permeability and coagulation disorders. T cell activation is a critical event for an effective immune response against infection, including the production of cytokines. We aim to reveal mechanisms that modulate the virus-cell interaction, with an emphasis on cell death. Apoptosis is involved in lymphocyte homeostasis, contributes to the clearance of virus-infected cells but also may play a role in the pathogenesis. Phosphatidylserine exposure on CD8T lymphocytes from dengue patients support early apoptotic processes and loss of genomic integrity, observed by DNA fragmentation in T lymphocytes and indicating late apoptosis. These T cells express activation and cytotoxic phenotypes as revealed by CD29 and CD107a upregulation. Higher frequencies of CD95 were detected in T lymphocytes mainly in those with the cytotoxic profile (CD107a+) and lower levels of anti-apoptotic molecule Bcl-2, suggesting that both CD4+ and CD8+ T cell subsets are more susceptible to apoptosis during acute dengue. The analysis of apoptosis-related protein expression profile showed that not only molecules with pro- but also those with anti-apoptotic functions are overexpressed, indicating that survival mechanisms could be possibly protecting cells against apoptosis caused by viral, immune, oxidative and/or genotoxic stresses. These observations led us to propose that in dengue patients there is an association between T cell susceptibility to apoptosis and the activation state. The mechanisms for understanding the immunopathogenesis during dengue infection are discussed.

  20. A combined stress hormone infusion decreases in vivo protein synthesis in human T lymphocytes in healthy volunteers.

    PubMed

    Januszkiewicz, A; Essén, P; McNurlan, M A; Ringdén, O; Garlick, P J; Wernerman, J

    2001-11-01

    In vivo protein synthesis decreases in mononuclear cells following a combined stress hormone infusion given to healthy volunteers as a human trauma model. Here, the purpose was to further investigate this finding and to measure in vivo protein synthesis in isolated T lymphocytes. Furthermore, the effects of stress hormones on the lymphocyte subpopulations and mononuclear cells, characterized by flow cytometry and phytohemagglutinin (PHA)-induced and unstimulated proliferative responses in vitro, were elucidated. Healthy volunteers (n = 16) were randomized into 2 groups to receive either a stress hormone or a saline infusion for 6 hours. In vivo protein synthesis was studied before and after the treatment by measuring the incorporation of stable isotopically-labeled phenylalanine into lymphocyte and mononuclear cell proteins. Protein synthesis decreased after stress hormone infusion in both cell populations: in T lymphocytes from 13.0% +/- 0.7%/d (mean +/- SD) to 8.6% +/- 2.1%/d (P <.01) and in mononuclear cells from 13.3% +/- 1.2%/d to 6.3 +/- 2.0%/d (P <.001). No change in proliferative responsiveness in vitro was observed. The stress hormone infusion produced a decrease in the percentage of T helper CD3/CD4 from 41% to 18% (P <.001), T cytotoxic CD3/CD8 from 27% to 15% (P <.001), as well as total T CD3 cells from 69% to 35% (P <.001). There was an increase in the percentage of natural killer (NK) cells CD16/CD56 from 17% to 55% (P <.001). Determination of phenotypes expressed on activated T lymphocytes showed that CD3/HLA-DR was unchanged and CD3/CD25 decreased from 14% to 7% (P <.01) in the stress hormone group. The study showed that the decrease of in vivo protein synthesis was 34% in T lymphocytes as compared with 53% in mononuclear cells, when determined immediately after a 6-hour stress hormone infusion. This change was associated with a pronounced decrease in all lymphocyte subpopulations, except for the NK cells, which increased substantially.

  1. Replication-Competent Foamy Virus Vaccine Vectors as Novel Epitope Scaffolds for Immunotherapy

    PubMed Central

    Lei, Janet; Osen, Wolfram; Gardyan, Adriane; Hotz-Wagenblatt, Agnes; Wei, Guochao; Gissmann, Lutz; Eichmüller, Stefan; Löchelt, Martin

    2015-01-01

    The use of whole viruses as antigen scaffolds is a recent development in vaccination that improves immunogenicity without the need for additional adjuvants. Previous studies highlighted the potential of foamy viruses (FVs) in prophylactic vaccination and gene therapy. Replication-competent FVs can trigger immune signaling and integrate into the host genome, resulting in persistent antigen expression and a robust immune response. Here, we explored feline foamy virus (FFV) proteins as scaffolds for therapeutic B and T cell epitope delivery in vitro. Infection- and cancer-related B and T cell epitopes were grafted into FFV Gag, Env, or Bet by residue replacement, either at sites of high local sequence homology between the epitope and the host protein or in regions known to tolerate sequence alterations. Modified proviruses were evaluated in vitro for protein steady state levels, particle release, and virus titer in permissive cells. Modification of Gag and Env was mostly detrimental to their function. As anticipated, modification of Bet had no impact on virion release and affected virus titers of only some recombinants. Further evaluation of Bet as an epitope carrier was performed using T cell epitopes from the model antigen chicken ovalbumin (OVA), human tyrosinase-related protein 2 (TRP-2), and oncoprotein E7 of human papillomavirus type 16 (HPV16E7). Transfection of murine cells with constructs encoding Bet-epitope chimeric proteins led to efficient MHC-I-restricted epitope presentation as confirmed by interferon-gamma enzyme-linked immunospot assays using epitope-specific cytotoxic T lymphocyte (CTL) lines. FFV infection-mediated transduction of cells with epitope-carrying Bet also induced T-cell responses, albeit with reduced efficacy, in a process independent from the presence of free peptides. We show that primate FV Bet is also a promising T cell epitope carrier for clinical translation. The data demonstrate the utility of replication-competent and -attenuated

  2. Selection of Conserved Epitopes from Hepatitis C Virus for Pan-Populational Stimulation of T-Cell Responses

    PubMed Central

    Molero-Abraham, Magdalena; Lafuente, Esther M.; Flower, Darren R.; Reche, Pedro A.

    2013-01-01

    The hepatitis C virus (HCV) is able to persist as a chronic infection, which can lead to cirrhosis and liver cancer. There is evidence that clearance of HCV is linked to strong responses by CD8 cytotoxic T lymphocytes (CTLs), suggesting that eliciting CTL responses against HCV through an epitope-based vaccine could prove an effective means of immunization. However, HCV genomic plasticity as well as the polymorphisms of HLA I molecules restricting CD8 T-cell responses challenges the selection of epitopes for a widely protective vaccine. Here, we devised an approach to overcome these limitations. From available databases, we first collected a set of 245 HCV-specific CD8 T-cell epitopes, all known to be targeted in the course of a natural infection in humans. After a sequence variability analysis, we next identified 17 highly invariant epitopes. Subsequently, we predicted the epitope HLA I binding profiles that determine their potential presentation and recognition. Finally, using the relevant HLA I-genetic frequencies, we identified various epitope subsets encompassing 6 conserved HCV-specific CTL epitopes each predicted to elicit an effective T-cell response in any individual regardless of their HLA I background. We implemented this epitope selection approach for free public use at the EPISOPT web server. PMID:24348677

  3. Characterization of CD3(+) T lymphocytes of Japanese flounder (Paralichthys olivaceus) and its response after immunization with formalin-inactivated Edwardsiella tarda.

    PubMed

    Tang, Xiaoqian; Qin, Yinghui; Sheng, Xiuzhen; Xing, Jing; Zhan, Wenbin

    2017-04-01

    The CD3 complex is an important cell surface marker of T lymphocytes and essential for T lymphocytes activation in higher vertebrates. In the present work, the CD3ε of Japanese flounder (Paralichthys olivaceus) was recombinantly expressed in E. coli BL21 (DE3) and used as an immunogen to produce mouse anti-rCD3ε polyclonal antibodies, which could specifically recognize a 20 kDa protein in the membrane proteins of peripheral blood lymphocytes (PBL) of Japanese flounder by co-immunoprecipitation assay. Mass spectrometric analysis showed the 20 kDa protein was the native CD3ε of Japanese flounder. Both the flow cytometric analysis and double immunofluorescence assay (DIFA) showed that the CD3(+) T lymphocytes could be identified specifically by the mouse anti-rCD3ε polyclonal antibodies, which didn't cross-react with the sIgM(+) lymphocytes. Immunohistochemistry showed that CD3(+) T lymphocytes could be detected in gill, skin, stomach, intestine, spleen, liver, head-kidney and mid-kidney. Flow cytometric analysis showed the percentages of CD3(+) T lymphocytes in the PBL, spleen lymphocytes (SL) and head-kidney lymphocytes (HKL) of Japanese flounder increased rapidly after immunization with formalin-inactivated Edwardsiella tarda, and reached their peak levels at 5th day with 12.6%, 9.7% and 8.7%, respectively, and then decreased gradually. These results suggested that CD3(+) T lymphocytes play important roles in mucosal and cell-mediated immunity, and the results would deepen our understanding on the roles of teleost T lymphocytes in the immune response.

  4. Differential sensitivity of T lymphocytes and hematopoietic precursor cells to photochemotherapy with 8-methoxypsoralen and ultraviolet A light.

    PubMed

    Mabed, Mohamed; Coffe, Christian; Racadot, Evelyne; Angonin, Regis; Pavey, Jean-Jaques; Tiberghien, Pierre; Herve, Patrick

    2006-01-01

    The combination of 8-methoxypsoralen (8-MOP) and long wave ultraviolet radiation (UV-A) has immunomodulatory effects and might abolish both graft-vs-host and host-vs-graft reactions after allogeneic hematopoietic stem cell transplantation. In the present study, we have confirmed the sensitivity of T lymphocytes to 8-MOP treatment plus UV-A exposure as evidenced by the abrogation of the alloreactivity in mixed lymphocyte cultures as well as the inhibition of the response to phytohemagglutinin A. However, the clonogenic capacity of the bone marrow hematopoietic progenitors was inhibited with UV-A doses lower than the doses needed to inhibit T-lymphocytes alloreactivity. Moreover, long-term bone marrow cultures showed that 8-MOP plus UV-A treatment had detrimental effects on the more immature bone marrow stem cells. These data were confirmed when murine bone marrow graft was treated with 8-MOP, exposed to UV-A, then transplanted into semiallogeneic recipient mice. The treated cells could not maintain their clonogenic capacity in vivo resulting in death of all animals. Taken together, these data show that ex vivo 8-MOP plus UV-A treatment of the marrow graft cannot be used to prevent post-bone marrow transplantation alloreactivity.

  5. The Suppressed Induction of Human Mature Cytotoxic T Lymphocytes Caused by Asbestos Is Not due to Interleukin-2 Insufficiency.

    PubMed

    Kumagai-Takei, Naoko; Nishimura, Yasumitsu; Matsuzaki, Hidenori; Lee, Suni; Yoshitome, Kei; Hayashi, Hiroaki; Otsuki, Takemi

    2016-01-01

    We previously reported that exposure to chrysotile B (CB) asbestos suppressed the induction of mature cytotoxic T lymphocytes (CTLs) during mixed lymphocyte reaction assays (MLRs) with a decrease in the proliferation of immature CTLs. However, the mechanism responsible for the effect of asbestos fibers on the differentiation of CTLs remains unclear. Since interleukin-2 (IL-2) is a regulator of T lymphocyte proliferation, we examined the effect of IL-2 addition on suppressed CTL differentiation in CB-exposed cultures using flow cytometry (FCM). When IL-2 was added at 1 ng/mL on the second day of MLRs, the asbestos-caused decreases in the proliferation and percentages of CD25(+) and CD45RO(+) cells in CD8(+) lymphocytes were not recovered by IL-2 addition, although the decrease in percentage of granzyme B(+) cells was partially recovered. CD8(+) lymphocytes from the IL-2-treated culture with asbestos showed the same degree of cytotoxicity as those in cultures without IL-2 or asbestos. These findings indicate that IL-2 insufficiency is not the main cause for the suppressed induction of CTLs by asbestos exposure, although they suggest a potential for the improvement of such suppressed CTL functions. Secretory factors other than IL-2 in addition to membrane-bound stimulatory molecules may play a role in asbestos-caused suppressed CTL differentiation.

  6. Effects of moderate and severe malnutrition in rats on splenic T lymphocyte subsets and activation assessed by flow cytometry

    PubMed Central

    Cortés-Barberena, E; González-Márquez, H; Gómez-Olivares, J L; Ortiz-Muñiz, R

    2008-01-01

    Malnutrition is distributed widely throughout the world and is a particular problem in developing countries. Laboratory animals have been very useful in studying the effects of varying levels of malnutrition because non-nutritional factors that affect humans may be controlled. The objective of the present study was to determine the effects of moderate and severe malnutrition on lymphocyte proportions and activation markers of T cells in experimentally malnourished rats during lactation by flow cytometry. Lower absolute (total) and relative (%) numbers of CD3+ and CD4+ lymphocyte subpopulations were observed in moderately (second degree) and severely (third degree) malnourished rats compared with well-nourished rats (P < 0·05). Both groups of malnourished rats showed a significant decrease in the percentage of CD71+ cells at 24 h post-activation with phytohaemagglutinin (PHA). After 24 h activation of spleen cells with PHA, a lower percentage of CD25+ cells was observed in malnourished than well-nourished rats (P < 0·05). In conclusion, the results of this study indicated an altered expression of CD71 and CD25 during activation of T lymphocytes in malnourished rats and may partially explain increased susceptibility to infection associated with malnutrition. Moreover, these results demonstrated that moderate malnutrition affects the response of T lymphocytes as much as severe malnutrition. PMID:18373698

  7. T lymphocyte subpopulations defined by two sets of monoclonal antibodies in chronic active hepatitis and systemic lupus erythematosus.

    PubMed Central

    Frazer, I H; Mackay, I R

    1982-01-01

    Lymphocyte subpopulations were enumerated in human peripheral blood using murine monoclonal antibodies with specificity for all peripheral blood T lymphocytes (OKT3, alpha-Leu 1) and for the helper subset (OKT4, alpha Leu 3a) and suppressor/cytotoxic subset (OKT8, alpha Leu 2a). Patients with chronic active hepatitis (CAH) (23) or systemic lupus erythematosus (SLE) (10), compared with healthy subjects (20), had a lower mean T lymphocyte count. Patients with CAH had normal numbers of suppressor/cytotoxic (TSC) cells, but fewer helper (TH) cells than healthy subjects (0 . 96 +/- 0 . 11 X 10(9)/1 versus 1 . 45 +/- 0 . 15 X 10(9)/1), and those with SLE also had fewer TH cells (0 . 93 +/- 0 . 11 X 10(9)/1). Patients with CAH receiving azathioprine (n = 8) had significantly fewer TSC cells, and a higher TH/TSC ratio (2 . 69 +/- 0 . 35) than those (n = 15) not on this therapy (1 . 85 +/- 0 . 15). When patients taking azathioprine were excluded, no correlation was found between disease activity and the TH/TSC ratio for either disease. PMID:6216997

  8. Cancer-induced defective cytotoxic T lymphocyte effector function: another mechanism how antigenic tumors escape immune-mediated killing.

    PubMed Central

    Radoja, S.; Frey, A. B.

    2000-01-01

    BACKGROUND: The notion that a deficit in immune cell functions permits tumor growth has received experimental support with the discovery of several different biochemical defects in T lymphocytes that infiltrate cancers. Decreased levels of enzymes involved with T-cell signal transduction have been reported by several laboratories, suggesting that tumors or host cells recruited to the tumor site actively down-regulate antitumor T-cell immune response. This permits tumor escape from immune-mediated killing. The possibility that defects in T-cell signal transduction can be reversed, which would potentially permit successful vaccination or adoptive immunotherapy, motivates renewed interest in the field. Summarizing the literature concerning tumor-induced T-cell dysfunction, we focus on the end stage of immune response to human cancer, that of defective cytotoxic T lymphocyte killing function. Based on the data from several laboratories, we hypothesize a biochemical mechanism that accounts for the unusual phenotype of antitumor T-cell accumulation in tumors, but with defective killing function. PMID:10972084

  9. T Lymphocytes and Inflammatory Mediators in the Interplay between Brain and Blood in Alzheimer's Disease: Potential Pools of New Biomarkers

    PubMed Central

    Mietelska-Porowska, Anna

    2017-01-01

    Alzheimer's disease (AD) is a chronic neurodegenerative disorder and the main cause of dementia. The disease is among the leading medical concerns of the modern world, because only symptomatic therapies are available, and no reliable, easily accessible biomarkers exist for AD detection and monitoring. Therefore extensive research is conducted to elucidate the mechanisms of AD pathogenesis, which seems to be heterogeneous and multifactorial. Recently much attention has been given to the neuroinflammation and activation of glial cells in the AD brain. Reports also highlighted the proinflammatory role of T lymphocytes infiltrating the AD brain. However, in AD molecular and cellular alterations involving T cells and immune mediators occur not only in the brain, but also in the blood and the cerebrospinal fluid (CSF). Here we review alterations concerning T lymphocytes and related immune mediators in the AD brain, CSF, and blood and the mechanisms by which peripheral T cells cross the blood brain barrier and the blood-CSF barrier. This knowledge is relevant for better AD therapies and for identification of novel biomarkers for improved AD diagnostics in the blood and the CSF. The data will be reviewed with the special emphasis on possibilities for development of AD biomarkers. PMID:28293644

  10. Estimating the number of hematopoietic or lymphoid stem cells giving rise to clonal chromosome aberrations in blood T lymphocytes.

    PubMed

    Nakano, M; Kodama, Y; Ohtaki, K; Itoh, M; Awa, A A; Cologne, J; Kusunoki, Y; Nakamura, N

    2004-03-01

    Quantifying the proliferative capacity of long-term hematopoietic stem cells in humans is important for bone marrow transplantation and gene therapy. Obtaining appropriate data is difficult, however, because the experimental tools are limited. We hypothesized that tracking clonal descendants originating from hematopoietic stem cells would be possible if we used clonal chromosome aberrations as unique tags of individual hematopoietic stem cells in vivo. Using FISH, we screened 500 blood T lymphocytes from each of 513 atomic bomb survivors and detected 96 clones composed of at least three cells with identical aberrations. The number of clones was inversely related to their population size, which we interpreted to mean that the progenitor cells were heterogeneous in the number of progeny that they could produce. The absolute number of progenitor cells contributing to the formation of the observed clones was estimated as about two in an unexposed individual. Further, scrutiny of ten clones revealed that lymphocyte clones could originate roughly equally from hematopoietic stem cells or from mature T lymphocytes, thereby suggesting that the estimated two progenitor cells are shared as one hematopoietic stem cell and one mature T cell. Our model predicts that one out of ten people bears a non- aberrant clone comprising >10% of the total lymphocytes, which indicates that clonal expansions are common and probably are not health-threatening.

  11. UCP2 up-regulation within the course of autoimmune encephalomyelitis correlates with T-lymphocyte activation.

    PubMed

    Smorodchenko, Alina; Schneider, Stephanie; Rupprecht, Anne; Hilse, Karoline; Sasgary, Soleman; Zeitz, Ute; Erben, Reinhold G; Pohl, Elena E

    2017-04-01

    Multiple sclerosis (MS) is an inflammatory demyelinating autoimmune disorder of the central nervous system (CNS) associated with severe neurological disability. Reactive oxygen species (ROS) and mitochondrial dysfunction play a pivotal role in the pathogenesis of this disease. Several members of the mitochondrial uncoupling protein subfamily (UCP2-UCP5) were suggested to regulate ROS by diminishing the mitochondrial membrane potential and constitute therefore a promising pharmacological target for MS. To evaluate the role of different uncoupling proteins in neuroinflammation, we have investigated their expression patterns in murine brain and spinal cord (SC) during different stages of experimental autoimmune encephalomyelitis (EAE), an animal model for MS. At mRNA and protein levels we found that only UCP2 is up-regulated in the SC, but not in brain. The increase in UCP2 expression was antigen-independent, reached its maximum between 14 and 21days in both OVA and MOG immunized animals and correlated with an augmented number of CD3(+) T-lymphocytes in SC parenchyma. The decrease in abundance of UCP4 was due to neuronal injury and was only detected in CNS of MOG-induced EAE animals. The results provide evidence that the involvement of mitochondrial UCP2 in CNS inflammation during EAE may be mainly explained by the invasion of activated T-lymphocytes. This conclusion coincides with our previous observation that UCP2 is up-regulated in activated and rapidly proliferating T-cells and participates in fast metabolic re-programming of cells during proliferation.

  12. Vaccination with Mycobacterium bovis BCG affects the distribution of Fc receptor-bearing T lymphocytes in experimental pulmonary tuberculosis.

    PubMed Central

    Bartow, R A; McMurray, D N

    1989-01-01

    Inbred strain 2 guinea pigs were vaccinated with Mycobacterium bovis BCG or were left unvaccinated and challenged 6 weeks later by the respiratory route with virulent Mycobacterium tuberculosis. By using a double rosette assay with isotype-specific antibody-coated ox and uncoated rabbit erythrocytes, the proportions of T lymphocytes bearing Fc receptors for immunoglobulin G (IgG) (T gamma cells) or IgM (T mu cells) were quantified in tissues taken from animals that were killed within 4 weeks postchallenge. Tuberculin reactivity in vivo and in vitro and antimycobacterial resistance were also measured. BCG vaccination protected the guinea pigs and resulted in significantly enhanced proportions of T mu cells in the blood during the first 3 weeks and in the spleen during weeks 2 and 3 postchallenge. Levels of T gamma cells declined in all tissues during the first 3 weeks of infection and were unaffected by prior vaccination with BCG. Increased proportions of T mu cells in the blood were accompanied by dramatic tuberculin skin reactions and purified protein derivative-induced lymphoproliferation in BCG-vaccinated guinea pigs during the first 2 weeks following virulent pulmonary challenge. Peak levels of T mu cells in the spleens of vaccinated animals at 2 weeks coincided with the first appearance of virulent mycobacteria in that organ. BCG vaccination appears to influence immunoregulatory events in pulmonary tuberculosis through effects on the distribution of IgM Fc receptor-bearing (T mu cell) T lymphocytes. PMID:2523350

  13. The Suppressed Induction of Human Mature Cytotoxic T Lymphocytes Caused by Asbestos Is Not due to Interleukin-2 Insufficiency

    PubMed Central

    Kumagai-Takei, Naoko; Lee, Suni; Yoshitome, Kei; Hayashi, Hiroaki

    2016-01-01

    We previously reported that exposure to chrysotile B (CB) asbestos suppressed the induction of mature cytotoxic T lymphocytes (CTLs) during mixed lymphocyte reaction assays (MLRs) with a decrease in the proliferation of immature CTLs. However, the mechanism responsible for the effect of asbestos fibers on the differentiation of CTLs remains unclear. Since interleukin-2 (IL-2) is a regulator of T lymphocyte proliferation, we examined the effect of IL-2 addition on suppressed CTL differentiation in CB-exposed cultures using flow cytometry (FCM). When IL-2 was added at 1 ng/mL on the second day of MLRs, the asbestos-caused decreases in the proliferation and percentages of CD25+ and CD45RO+ cells in CD8+ lymphocytes were not recovered by IL-2 addition, although the decrease in percentage of granzyme B+ cells was partially recovered. CD8+ lymphocytes from the IL-2-treated culture with asbestos showed the same degree of cytotoxicity as those in cultures without IL-2 or asbestos. These findings indicate that IL-2 insufficiency is not the main cause for the suppressed induction of CTLs by asbestos exposure, although they suggest a potential for the improvement of such suppressed CTL functions. Secretory factors other than IL-2 in addition to membrane-bound stimulatory molecules may play a role in asbestos-caused suppressed CTL differentiation. PMID:27975069

  14. Natural variants of cytotoxic epitopes are T-cell receptor antagonists for antiviral cytotoxic T cells

    NASA Astrophysics Data System (ADS)

    Bertoletti, Antonio; Sette, Alessandro; Chisari, Francis V.; Penna, Amalia; Levrero, Massimo; Carli, Marco De; Fiaccadori, Franco; Ferrari, Carlo

    1994-06-01

    IT has been suggested that mutations within immunodominant cytotoxic T-lymphocyte (CTL) epitopes may be exploited by viruses to evade protective immune responses critical for clearance1-4. Viral escape could originate from passive mechanisms, such as mutations within crucial CTL epitopes, either affecting major histocompatibility complex binding or T-cell antigen receptor (TCR) recognition. Additionally, it has recently been shown that substitutions of TCR contact sites can yield analogue peptides that can still interact with the T-cell receptor but be unable to deliver a full stimulatory signal, thus inducing anergy5 or acting as an antagonist for the TCR6-8. We report here that hepatitis B virus isolates derived from two chronically infected patients display variant epitopes that act as natural TCR antagonists with the capacity to inhibit the CTL response to the wild-type epitope. During natural infection, TCR antagonist mutations of CTL epitopes could contribute to the development of viral persistence, especially if the antiviral CTL response is monospecific or the epitope is strongly immunodominant.

  15. Design of immunogenic and effective multi-epitope DNA vaccines for melanoma.

    PubMed

    Cho, Hyun-Il; Celis, Esteban

    2012-03-01

    Plasmid DNA vaccination is an attractive way to elicit T cell responses against infectious agents and tumor cells. DNA constructs can be designed to contain multiple T cell epitopes to generate a diverse immune response to incorporate numerous antigens and to reduce limitations due to MHC restriction into a single entity. We have prepared cDNA plasmid constructs containing several mouse T cell epitopes connected by either furin-sensitive or furin-resistant linkers and studied the effects of a cationic cell-penetrating sequence from HIV-tat. Significant CD8 T cell responses were obtained with multi-epitope DNA vaccines followed by in vivo electroporation regardless of the type of linker used and whether the construct had the HIV-tat sequence. The magnitude of immune responses was very similar to all CD8 T cell epitopes contained within each vaccine construct, indicating the absence of immunodominance. Incorporating a T helper epitope into the constructs increased the T cell responses. Prophylactic and therapeutic antitumor responses against B16 melanoma were obtained using a construct containing epitopes from melanosomal proteins, indicating that this vaccination was successful in generating responses to self-antigens that potentially may be subjected to immune tolerance. These findings are useful for designing DNA vaccines for a multitude of diseases where T lymphocytes play a protective or therapeutic role.

  16. CD8 epitope escape and reversion in acute HCV infection.

    PubMed

    Timm, Joerg; Lauer, Georg M; Kavanagh, Daniel G; Sheridan, Isabelle; Kim, Arthur Y; Lucas, Michaela; Pillay, Thillagavathie; Ouchi, Kei; Reyor, Laura L; Schulze zur Wiesch, Julian; Gandhi, Rajesh T; Chung, Raymond T; Bhardwaj, Nina; Klenerman, Paul; Walker, Bruce D; Allen, Todd M

    2004-12-20

    In the setting of acute hepatitis C virus (HCV) infection, robust HCV-specific CD8+ cytotoxic T lymphocyte (CTL) responses are associated with initial control of viremia. Despite these responses, 70-80% of individuals develop persistent infection. Although viral escape from CD8 responses has been illustrated in the chimpanzee model of HCV infection, the effect of CD8 selection pressure on viral evolution and containment in acute HCV infection in humans remains unclear. Here, we examined viral evolution in an immunodominant human histocompatibility leukocyte antigen (HLA)-B8-restricted NS3 epitope in subjects with acute HCV infection. Development of mutations within the epitope coincided with loss of strong ex vivo tetramer and interferon gamma enzyme-linked immunospot responses, and endogenous expression of variant NS3 sequences suggested that the selected mutations altered processing and presentation of the variant epitope. Analysis of NS3 sequences from 30 additional chronic HCV-infected subjects revealed a strong association between sequence variation within this region and expression of HLA-B8, supporting reproducible allele-specific selection pressures at the population level. Interestingly, transmission of an HLA-B8-associated escape mutation to an HLA-B8 negative subject resulted in rapid reversion of the mutation. Together, these data indicate that viral escape from CD8+ T cell responses occurs during human HCV infection and that acute immune selection pressure is of sufficient magnitude to influence HCV evolution.

  17. Macrophages from disease resistant B2 haplotype chickens activate T lymphocytes more effectively than macrophages from disease susceptible B19 birds.

    PubMed

    Collisson, Ellen; Griggs, Lisa; Drechsler, Yvonne

    2017-02-01

    Resistance to respiratory pathogens, including coronavirus-induced infection and clinical illness in chickens has been correlated with the B (MHC) complex and differential ex vivo macrophage responses. In the current study, in vitro T lymphocyte activation measured by IFNγ release was significantly higher in B2 versus B19 haplotypes. AIV infection of macrophages was required to activate T lymphocytes and prior in vivo exposure of chickens to NP AIV plasmid enhanced responses to infected macrophages. This study suggests that the demonstrated T lymphocyte activation is in part due to antigen presentation by the macrophages as well as cytokine release by the infected macrophages, with B2 haplotypes showing stronger activation. These responses were present both in CD4 and CD8 T lymphocytes. In contrast, T lymphocytes stimulated by ConA showed greater IFNγ release of B19 haplotype cells, further indicating the greater responses in B2 haplotypes to infection is due to macrophages, but not T cells. In summary, resistance of B2 haplotype chickens appears to be directly linked to a more vigorous innate immune response and the role macrophages play in activating adaptive immunity.

  18. Alpharetroviral self-inactivating vectors produced by a superinfection-resistant stable packaging cell line allow genetic modification of primary human T lymphocytes.

    PubMed

    Labenski, Verena; Suerth, Julia D; Barczak, Elke; Heckl, Dirk; Levy, Camille; Bernadin, Ornellie; Charpentier, Emmanuelle; Williams, David A; Fehse, Boris; Verhoeyen, Els; Schambach, Axel

    2016-08-01

    Primary human T lymphocytes represent an important cell population for adoptive immunotherapies, including chimeric-antigen and T-cell receptor applications, as they have the capability to eliminate non-self, virus-infected and tumor cells. Given the increasing numbers of clinical immunotherapy applications, the development of an optimal vector platform for genetic T lymphocyte engineering, which allows cost-effective high-quality vector productions, remains a critical goal. Alpharetroviral self-inactivating vectors (ARV) have several advantages compared to other vector platforms, including a more random genomic integration pattern and reduced likelihood for inducing aberrant splicing of integrated proviruses. We developed an ARV platform for the transduction of primary human T lymphocytes. We demonstrated functional transgene transfer using the clinically relevant herpes-simplex-virus thymidine kinase variant TK.007. Proof-of-concept of alpharetroviral-mediated T-lymphocyte engineering was shown in vitro and in a humanized transplantation model in vivo. Furthermore, we established a stable, human alpharetroviral packaging cell line in which we deleted the entry receptor (SLC1A5) for RD114/TR-pseudotyped ARVs to prevent superinfection and enhance genomic integrity of the packaging cell line and viral particles. We showed that superinfection can be entirely prevented, while maintaining high recombinant virus titers. Taken together, this resulted in an improved production platform representing an economic strategy for translating the promising features of ARVs for therapeutic T-lymphocyte engineering.

  19. Identification of novel Lck-derived T helper epitope long peptides applicable for HLA-A2(+) cancer patients as cancer vaccine.

    PubMed

    Matsueda, Satoko; Shichijo, Shigeki; Nagata, Sayaka; Seki, Chieko; Yamada, Akira; Noguchi, Masanori; Itoh, Kyogo

    2015-11-01

    The present study attempted to identify T helper epitope long peptides capable of inducing cytotoxic T lymphocytes (CTL) from Lck antigen (p56(Lck) ), the src family tyrosine kinase, which is known to be aberrantly expressed in metastatic cancers cells, in order to develop a long peptide-based cancer vaccine for HLA-A2(+) cancer patients. Based on the biding motif to the HLA-DR and HLA-A2 alleles, 94 peptides were prepared from the Lck antigen. These peptides were screened for their reactivity to immunoglobulin G (IgG) from plasma of cancer patients, followed by testing of their ability to induce both CD4(+) and CD8(+) T lymphocytes showing not only peptide-specific IFN-γ production but cytotoxicity against HLA-A2(+) cancer cells from peripheral blood mononuclear cells (PBMC) of HLA-A2(+) cancer patients. Among 94 peptides tested, the three T helper epitope long peptides and their inner CTL epitope short peptides with HLA-A2 binding motifs were frequently recognized by IgG of cancer patients, and efficiently induced both CD4(+) IFN-γ(+) and CD8(+) IFN-γ(+) T lymphocytes. Patients' PBMC stimulated with these long peptides showed cytotoxicity against HLA-A2(+) Lck(+) cancer cells in HLA-class I and HLA-class II dependent manners. These three peptides might be useful for long peptide-based vaccines for HLA-A2(+) cancer patients with Lck(+) tumor cells.

  20. Evaluation of the ability of N-terminal fragment of lethal factor of Bacillus anthracis for delivery of Mycobacterium T cell antigen ESAT-6 into cytosol of antigen presenting cells to elicit effective cytotoxic T lymphocyte response

    SciTech Connect

    Chandra, Subhash; Kaur, Manpreet; Midha, Shuchi; Bhatnagar, Rakesh . E-mail: rakbhat01@yahoo.com; Banerjee-Bhatnagar, Nirupama . E-mail: nirupama@icgeb.res.in

    2006-12-22

    We report the ability of N-terminal fragment of lethal factor of Bacillus anthracis to deliver genetically fused ESAT-6 (early secretory antigen target), a potent T cell antigen of Mycobacterium tuberculosis, into cytosol to elicit Cytotoxic T lymphocyte (CTL) response. In vitro Th1 cytokines data and CTL assay proved that efficient delivery of LFn.ESAT-6 occurs in cytosol, in the presence of protective antigen (PA), and leads to generation of effective CTL response. Since CTL response is essential for protection against intracellular pathogens and, it is well known that only single T cell epitope or single antigenic protein is not sufficient to elicit protective CTL response due to variation or polymorphism in MHC-I alleles among the individuals, we suggest that as a fusion protein LFn can be used to deliver multiepitopes of T cells or multiproteins which can generate effective CTLs against intracellular pathogens like M. tuberculosis. It can be used to enhance the protective efficacy of BCG vaccine.

  1. Identification and characterization of pro-T lymphocytes and lineage- uncommitted lymphocyte precursors from mice with three novel surface markers

    PubMed Central

    1990-01-01

    The study of prethymic stages of T cell development has been limited because specific markers for mouse pro-T lymphocytes were not available. We developed a panel of rat monoclonal antibodies (mAbs) that bind to our pro-T lymphocyte clones obtained from bone marrow of young adult mice and the thymus of 14-d-old embryos. The mAbs, called Joro 30-8, Joro 37-5, and Joro 75, were found to bind to all pro-T clones tested but not to cell lines representing later stages of T cell development, B lymphocyte, or myeloid lineages. We determined the frequency and tissue distribution in normal and immunodeficient mouse strains as well as the ontogeny in liver and thymus of cells positive for these mAbs. The results were consistent with the pattern of reactivity observed with cell lines. We isolated Joro 30-8+, Joro 37- 5+, and Joro 75+ bone marrow cells by cell sorter and found that: (a) phenotypically, they are Thy-1+, CD4-, CD8-, CD3-, B-220-, IgM-, F4/80- , and PgP-1+; (b) they grew in response to the combination of interleukin 3 (IL-3) + IL-4 or IL-3 + IL-4 + IL-6; and (c) Joro 37-5+ and Joro 75+ marrow cells gave rise to mature T lymphocytes but not to B lymphocytes, while Joro 30-8+ marrow cells generated both T and B lymphocytes after 8-12 wk of transfer into severe combined immunodeficient (Scid) mice. In normal mice subjected to 600 rad of irradiation to induce a wave of thymus recolonization, we found by flow fluorocytometry analysis that Joro+ cells entered the thymus 2 d after irradiation, expanded during the next 4 d, and underwent further differentiation, and from day 8 up to day 21, post-irradiation Joro+ cells were no longer detectable in the thymuses. Immunohistochemical analysis of normal thymus shows the presence of very few Joro 30-8+, Joro 37-5+, and Joro 75+ lymphoid cells in the subcapsular area and outer cortex but not in the medulla. The kinetic analysis of tissue sections from thymuses at various days post-irradiation suggests that Joro+ cells enter

  2. Epiligrin, a component of epithelial basement membranes, is an adhesive ligand for alpha 3 beta 1 positive T lymphocytes

    PubMed Central

    1993-01-01

    The cutaneous T cell lymphomas (CTCL), typified by mycosis fungoides, and several chronic T cell mediated dermatoses are characterized by the migration of T lymphocytes into the epidermis (epidermotropism). Alternatively, other types of cutaneous inflammation (malignant cutaneous B cell lymphoma, CBCL, or lymphocytoma cutis, non-malignant T or B cell type) do not show evidence of epidermotropism. This suggests that certain T lymphocyte subpopulations are able to interact with and penetrate the epidermal basement membrane. We show here that T lymphocytes derived from patients with CTCL (HUT 78 or HUT 102 cells), adhere to the detergent-insoluble extracellular matrix prepared from cultured basal keratinocytes (HFK ECM). HUT cell adhesion to HFK ECM was inhibitable with monoclonal antibodies (mAbs) directed to the alpha 3 (P1B5) or beta 1 (P4C10) integrin receptors, and could be up- regulated by an activating anti-beta 1 mAb (P4G11). An inhibitory mAb, P3H9-2, raised against keratinocytes identified epiligrin as the ligand for alpha 3 beta 1 positive T cells in HFK ECM. Interestingly, two lymphocyte populations could be clearly distinguished relative to expression of alpha 3 beta 1 by flow cytometry analysis. Lymphokine activated killer cells, alloreactive cytotoxic T cells and T cells derived from patients with CTCL expressed high levels of alpha 3 beta 1 (alpha 3 beta 1high). Non-adherent peripheral blood mononuclear cells, acute T or B lymphocytic leukemias, or non-cutaneous T or B lymphocyte cell lines expressed low levels of alpha 3 beta 1 (alpha 3 beta 1low). Resting PBL or alpha 3 beta 1low T or B cell lines did not adhere to HFK ECM or purified epiligrin. However, adhesion to epiligrin could be up-regulated by mAbs which activate the beta 1 subunit indicating that alpha 3 beta 1 activity is a function of expression and affinity. In skin derived from patients with graft-vs.-host (GVH) disease, experimentally induced delayed hypersensitivity reactions, and CTCL

  3. The impact of lower induction values of 50 Hz external electromagnetic fields on in vitro T lymphocyte adherence capabilities.

    PubMed

    Coček, Aleš; Hahn, Aleš; Mártonová, Jana; Ambruš, Miloslav; Dohnalová, Alena; Nedbalová, Martina; Jandová, Anna

    2012-06-01

    Our research thus far has concerned the impact of external electromagnetic fields (50 Hz) and low (0.01-10 mT) induction on adherence capabilities of T lymphocytes obtained from the blood of patients with head and neck tumors. We know that the in vitro adherence capability of T lymphocytes towards surfaces in cancer patients is less than that of control. Previously, we have found that exposure to electromagnetic fields (50 Hz/0.01-10 mT) increases the capability of T lymphocytes, in larynx/pharynx cancer patients, to adhere in vitro to surfaces, achieving almost physiological values, in not only pre-treatment patients but also those receiving treatment in the course of follow-up. The capability of T lymphocytes in controls (voluntary blood donors) to adhere to surfaces was also increased (50 Hz/0.01-0.5 mT). The present study concentrates on the significance of the level of electromagnetic field induction in order to determine whether low induction values can restore T lymphocytes adherence capabilities. Testing a subset of 20 patients showed a statistically significant difference (p<0.05) in the in vitro adherence capacity of T lymphocytes between both 0.01 and 0.05, and 0.1 mT induction levels. In the control group (patients diagnosed with chronic sensorineural hearing loss) there was even a statistically significant difference between induction values of 0.05 and 0.01 mT. A statistically significant difference (p<0.05) was also achieved with induction levels of 1 and 10 mT compared to 0.5, 0.1, and 0.05 mT, respectively. Therefore, we concluded that lower induction values resulted in a more biologically significant response.

  4. In vitro T lymphocyte adherence capabilities under the influence of lower induction values (0.1 - 0.01 mT) of 50 Hz external magnetic fields

    NASA Astrophysics Data System (ADS)

    Čoček, A.; Jandová, A.; Hahn, A.; Mártonová, J.; Ambruš, M.; Dohnalová, A.; Nedbalová, M.; Pokorný, J.

    2011-12-01

    Our research thus far has concerned the impact of external magnetic fields (50 Hz) and low (0.01-10 mT) induction on adherence capabilities of T lymphocytes obtained from the blood of patients with head and neck tumors. We know that the in vitro adherence capability of T lymphocytes towards surfaces in cancer patients is less than that of control. Previously, we have found that exposure to magnetic fields (50 Hz / 0.01-10 mT) increases the capability of T lymphocytes, in larynx/pharynx cancer patients, to adhere in vitro to surfaces, achieving almost physiological values, in not only pre-treatment patients but also those receiving treatment in the course of follow-up. The capability of T lymphocytes in controls (voluntary blood donors) to adhere to surfaces was also increased (50 Hz / 0.01-0.5 mT). The present study concentrates on the significance of the level of magnetic field induction in order to determine whether low induction values can restore T lymphocytes adherence capabilities. Testing a set of 20 patients showed a statistically significant difference (p < 0.05) in the in vitro adherence capacity of T lymphocytes between both 0.01 and 0.05, and 0.1 mT induction levels. In the control group (patients diagnosed with chronic sensorineural hearing loss) there was even a statistically significant difference between induction values of 0.05 and 0.01 mT. Therefore, we concluded that lower induction values resulted in a more biologically significant response.

  5. Membrane expression of NK receptors CD160 and CD158k contributes to delineate a unique CD4+ T-lymphocyte subset in normal and mycosis fungoides skin.

    PubMed

    Sako, Nouhoum; Schiavon, Valérie; Bounfour, Touda; Dessirier, Valérie; Ortonne, Nicolas; Olive, Daniel; Ram-Wolff, Caroline; Michel, Laurence; Sicard, Hélène; Marie-Cardine, Anne; Bagot, Martine; Bensussan, Armand; Schmitt, Christian

    2014-10-01

    CD160 is a GPI-anchored Ig-like receptor identified by the BY55 mAb on human circulating CD56dim+ NK cells and TCRγδ lymphocytes. In addition, while most intestinal T lymphocytes express it, only a minor circulating CD4+ or CD8+ T lymphocyte subset is CD160+. Here we describe a population of CD4+ CD160+ human blood T lymphocytes of circulating cutaneous T cells. These rare T lymphocytes represent 2.1 ± 1.9% of the circulating CD3+ CD4+ T cells, coexpress CD8αα, CD244, and perforin but lack CD28 expression, a phenotype corresponding to effector memory cytotoxic T-lymphocytes. Functional studies further confirmed their cytotoxic potential. These cells lack αEβ7 integrin and CCR7 expression but do express skin-addressing molecules CLA, and CCR4. In normal human skin, CD4+ CD160+ cells represent 34.6 ± 14.7% of the CD4+ T lymphocytes extracted by collagenase treatment. These T cells coexpress CLA (81 ± 13.6%), CCR4 (62.3 ± 15.9%), and some CD8αα (19.6 ± 13%) or CCR7 (24.4 ± 11.7%) expression. Cutaneous T-cell lymphoma cells express the natural killer receptor KIR3DL2 (CD158k) used as a tumor marker. Not only we confirmed the expression of this marker in the blood and/or skin of mycosis fungoides patients but we also show for the first time CD158k expression (often associated with CD160) on cutaneous CD4+ T cells from healthy individuals (25.3 ± 15%). Therefore, CD4+ CD160+ T cells expressing CD158k might represent specialized cutaneous lymphocytes devoted to immune surveillance, from which could originate cutaneous T-cell lymphomas such as mycosis fungoides.

  6. Mixed T Lymphocyte Chimerism after Allogeneic Hematopoietic Transplantation Is Predictive for Relapse of Acute Myeloid Leukemia and Myelodysplastic Syndromes.

    PubMed

    Lee, Hans C; Saliba, Rima M; Rondon, Gabriela; Chen, Julianne; Charafeddine, Yasmeen; Medeiros, L Jeffrey; Alatrash, Gheath; Andersson, Borje S; Popat, Uday; Kebriaei, Partow; Ciurea, Stefan; Oran, Betul; Shpall, Elizabeth; Champlin, Richard

    2015-11-01

    Chimerism testing after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in patients with acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) represents a promising tool for predicting disease relapse, although its precise role in this setting remains unclear. We investigated the predictive value of T lymphocyte chimerism analysis at 90 to 120 days after allo-HSCT in 378 patients with AML/MDS who underwent busulfan/fludarabine-based myeloablative preparative regimens. Of 265 (70%) patients with available T lymphocyte chimerism data, 43% of patients in first or second complete remission (CR1/CR2) at the time of transplantation had complete (100%) donor T lymphocytes at day +90 to +120 compared with 60% of patients in the non-CR1/CR2 cohort (P = .005). In CR1/CR2 patients, donor T lymphocyte chimerism ≤ 85% at day +90 to +120 was associated with a higher frequency of 3-year disease progression (29%; 95% confidence interval [CI], 18% to 46% versus 15%; 95% CI, 9% to 23%; hazard ratio [HR], 2.1; P = .04). However, in the more advanced, non-CR1/CR2 cohort, mixed T lymphocyte chimerism was not associated with relapse (37%; 95% CI, 20% to 66% versus 34%; 95% CI, 25% to 47%; HR, 1.3; P = .60). These findings demonstrate that early T lymphocyte chimerism testing at day +90 to +120 is a useful approach for predicting AML/MDS disease recurrence in patients in CR1/CR2 at the time of transplantation.

  7. Epitopes rationally selected through computational analyses induce T-cell proliferation in mice and are recognized by serum from individuals infected with Schistosoma mansoni.

    PubMed

    Lopes, Marcelo D; Oliveira, Flávio M; Coelho, Ivan E V; Passos, Maria J F; Alves, Clarice C; Taranto, Alex G; Júnior, Moacyr C; Santos, Luciana L; Fonseca, Cristina T; Villar, José A F P; Lopes, Débora O

    2017-04-03

    Schistosomiasis is the second leading cause of death due to parasitic diseases in the world. Seeking an alternative for the control of disease, the World Health Organization funded the genome sequencing of the major species related to schistosomiasis to identify potential vaccines and therapeutic targets. Therefore, the aim of this work was to select T and B-cell epitopes from Schistosoma mansoni through computational analyses and evaluate the immunological potential of epitopes in vitro. Extracellular regions of membrane proteins from the Schistosoma mansoni were used to predict promiscuous epitopes with affinity to different human Major Histocompatibility Class II (MHCII) molecules by bioinformatics analysis. The three-dimensional structure of selected epitopes was constructed and used in molecular docking to verify the interaction with murine MHCII H2-IA(b) . In this process, four epitopes were selected and synthesized to assess their ability to stimulate proliferation of CD4(+) T lymphocytes in mice splenocyte cultures. The results showed that Sm041370 and Sm168240 epitopes induced significant cell proliferation. Additionally, the four epitopes were used as antigens in the Indirect Enzyme-Linked Immunosorbent Assay (ELISA) to assess the recognition by serum from individuals infected with Schistosoma mansoni. Sm140560, Sm168240 and Sm041370 epitopes were recognized by infected individuals IgG antibodies. Therefore, Sm041370 and Sm168240 epitopes that stood out in in silico and in vitro analyses could be promising antigens in schistosomiasis vaccine development or diagnostic kits. This article is protected by copyright. All rights reserved.

  8. Selective impairment of T lymphocyte activation through the T cell receptor/CD3 complex after cytomegalovirus infection.

    PubMed Central

    Timón, M; Arnaiz-Villena, A; Ruiz-Contreras, J; Ramos-Amador, J T; Pacheco, A; Regueiro, J R

    1993-01-01

    Cytomegalovirus (CMV) infection is reported to cause transient immunosuppression in man. In this study we have analysed the effect of CMV on T lymphocyte function in 29 children diagnosed for acute CMV infection. Peripheral blood mononuclear cells (PBMC) obtained from the patients showed a significant specific impairment in their proliferative response to enterotoxins A and C1, to concanavalin A and to the anti-CD3 MoAb OKT3. The impaired responses were corrected with exogenous IL-2. In contrast, stimulation using phytohaemagglutinin, as well as activation signals delivered through the surface molecules CD26 or CD28, elicited normal proliferative responses in CMV PBMC. The results indicate that the T cell anergy associated with CMV infection is restricted to the T cell receptor/CD3 activation pathway. PMID:8403514

  9. T3 glycoprotein is functional although structurally distinct on human T-cell receptor. gamma. T lymphocytes

    SciTech Connect

    Krangel, M.S.; Bierer, B.E.; Devlin, P.; Clabby, M.; Strominger, J.L.; McLean, J.; Brenner, M.B.

    1987-06-01

    The T-cell receptor (TCR) ..gamma.. gene product occurs in association with T3 (CD3) polypeptides on the surface of human T lymphocytes. TCR ..gamma.. lymphocytes express arrays of T3 polypeptides distinct from those typically observed on TCR ..cap alpha beta.. lymphocytes. This report demonstrates that identical T3 ..gamma.., delta, and element of polypeptides are synthesized by TCR ..gamma.. lymphocytes and TCR ..cap alpha beta.. lymphocytes. However, the processing of T3 delta oligosaccharides is distinct in the two cell types. This observation may suggest distinct quaternary structures of these receptor complexes. Despite these structural differences, the T3 molecule on TCR ..gamma.. lymphocytes is functional. It is associated with and comodulates with TCR ..gamma.. and it serves as a substrate from protein kinase C-mediated phosphorylation. Anti-T3 monoclonal antibodies induce a rapid increase in cytoplasmic free calcium, indicating that the receptor complex is involved in signal transduction and triggering of TCR ..gamma.. lymphocytes.

  10. Differentiation and activation of γδ T Lymphocytes: Focus on CD27 and CD28 costimulatory receptors.

    PubMed

    Ribot, Julie C; Silva-Santos, Bruno

    2013-01-01

    γδ T lymphocytes are major providers of the pro-inflammatory cytokines interferon-γ (IFN-γ) and interleukin-17 (IL-17) at early stages of (auto)immune responses. We and others have recently described the phenotype and differentiation requirements of two distinct murine γδ T cell subsets producing either IFN-γ or IL-17. Here we summarize our current understanding of the molecular mechanisms that control γδ T cell differentiation, which is programmed in the thymus, and peripheral activation upon infection. We focus on the costimulatory receptors CD27 and CD28, which play independent and non-redundant roles in the physiology of γδ T cells in mice and in humans.

  11. Induction of cytotoxic T lymphocyte response against Mycobacterial antigen using domain I of anthrax edema factor as antigen delivery system

    SciTech Connect

    Chandra, Subhash; Kaur, Manpreet; Midha, Shuchi; Gorantala, Jyotsna; Bhatnagar, Rakesh . E-mail: rakbhat01@yahoo.com

    2007-05-25

    We have investigated the efficiency of N-terminal 1-260 residues of Edema factor (EFn) as a delivery system for ESAT-6, an antigenic protein of Mycobacterium tuberculosis H{sub 37}R{sub v}, into the cytosol of mammalian cells. The EFn.ESAT-6 recombinant protein was obtained by genetic fusion of EFn and ESAT-6 DNA. Our data shows that in the presence of PA, EFn.ESAT-6 fusion protein is internalized into the cytosol of antigen presenting cells, and the splenocytes produced both Th1 and Th2 cytokines in vitro. Further, EFn.ESAT-6 elicited effective cytotoxicT lymphocyte (CTL) response in an in vitro CTL assay. This study for the first time demonstrates that EFn can be used as a vehicle to deliver heterologous proteins of therapeutic importance.

  12. Dynamic visualization the whole process of cytotoxic T lymphocytes killing the B16 tumor cells in vitro

    NASA Astrophysics Data System (ADS)

    Qi, Shuhong; Zhang, Zhihong

    2016-03-01

    Cytotoxic T lymphocytes (CTLs) played a key role in the immune system to destroy the tumor cells. Although some mechanisms of CTLs killing the tumor cells are revealed already, the dynamic information of CTLs interaction with tumor cells are still not known very clearly. Here we used confocal microscopy to visualize the whole process of CTLs killing the tumor cells in vitro. The imaging data showed that CTLs destroyed the target tumor cells rapidly and efficiently. Several CTLs surrounded one or some tumor cells and the average time for CTLs destroying one tumor cell is just a few minutes in vitro. The study displayed the temporal events of CTLs interacting with tumor cells at the beginning and finally killing them and directly presented the efficient tumor cell cytotoxicity of the CTLs. The results helped us to deeply understand the mechanism of the CTLs destroying the tumor cells and to develop the cancer immunotherapy.

  13. Participation of V beta 4(+)-, V beta 7(+)-, and V beta 11(+)-T lymphocytes in haematogenously acquired Staphylococcus aureus nephritis.

    PubMed

    Verba, V; Tarkowski, A

    1996-09-01

    The most frequent pathogen in haematogenously acquired kidney infections in humans in Staphylococcus aureus. In order to characterize in situ the immunological patterns of septic nephritis we developed a murine model of this disease. A single intravenous injection of S. aureus producing toxic shock syndrome toxin-1 resulted in high frequency of inflammatory kidney lesions. Histopathologically, both focal and diffuse inflammatory infiltrates were seen in kidney cortex and medulla. Immunohistochemical evaluation revealed high numbers of Mac-1+ phagocytic cells as well as CD4(+)-and CD8(+)-lymphocytes. The expansion of lymphocytes carrying T-cell receptor V beta chain 4, 7, and 11 families in the kidney was observed. Our results suggest that the haematogenously acquired kidney infection by superantigen-producing staphylococci leads to migration, in situ activation and expansion of responding T-lymphocyte subsets.

  14. T-lymphocyte-rich Thymoma and Myasthenia Gravis in a Siberian Tiger (Panthera tigris altaica)☆

    PubMed Central

    Allan, K.; Masters, N.; Rivers, S.; Berry, K.; Routh, A.; Lamm, C.

    2014-01-01

    Summary A 10-year-old captive male Siberian tiger (Panthera tigris altaica) presented with acute onset collapse, vomiting and dyspnoea, preceded by a 6-month period of progressive muscle wasting. Following humane destruction, post-mortem examination revealed a large multilobulated mass in the cranial mediastinum, which was diagnosed as a T-lymphocyte-rich thymoma with the aid of immunohistochemistry. Retrospective serology for acetylcholine receptor antibodies (titre 3.90 nmol/l) confirmed a diagnosis of thymoma-associated myasthenia gravis. Thymomas are reported rarely in wild carnivores, but when detected they appear to be similar in morphology to those seen in domestic carnivores and may also be accompanied by paraneoplastic syndromes. The clinical signs of myasthenia gravis in the tiger were consistent with those reported in cats and dogs and the condition is proposed as an important differential diagnosis for generalized weakness in captive Felidae. PMID:24444818

  15. Chimeric virus-like particles for the delivery of an inserted conserved influenza A-specific CTL epitope.

    PubMed

    Cheong, Wan-Shoo; Reiseger, Jessica; Turner, Stephen John; Boyd, Richard; Netter, Hans-Jürgen

    2009-02-01

    The small hepatitis B virus surface antigens (HBsAg-S) have the ability to self-assemble with host-derived lipids into empty non-infectious virus-like particles (VLPs). HBsAg-S VLPs are the sole component of the licensed hepatitis B vaccine, and they are a useful delivery platform for foreign epitopes. To develop VLPs capable of transporting foreign cytotoxic T lymphocyte (CTL) epitopes, HBsAg-S specific CTL epitopes at various sites were substituted with a conserved CTL epitope derived from the influenza matrix protein. Depending on the insertion site, the introduction of the MHC class I A2.1-restricted influenza epitope was compatible with the secretion competence of HBsAg-S indicating that chimeric VLPs were assembled. Immunizations of transgenic HHDII mice with chimeric VLPs induced anti-influenza CTL responses proving that the inserted foreign epitope can be correctly processed and cross-presented. Chimeric VLPs in the absence of adjuvant were able to induce memory T cell responses, which could be recalled by influenza virus infections in the mouse model system. The ability of chimeric HBsAg-S VLPs to induce anti-foreign CTL responses and also with the proven ability to induce humoral immune responses constitute a highly versatile platform for the delivery of selected multiple epitopes to target disease associated infectious agents.

  16. Methamphetamine induces trace amine-associated receptor 1 (TAAR1) expression in human T lymphocytes: role in immunomodulation.

    PubMed

    Sriram, Uma; Cenna, Jonathan M; Haldar, Bijayesh; Fernandes, Nicole C; Razmpour, Roshanak; Fan, Shongshan; Ramirez, Servio H; Potula, Raghava

    2016-01-01

    The novel transmembrane G protein-coupled receptor, trace amine-associated receptor 1 (TAAR1), represents a potential, direct target for drugs of abuse and monoaminergic compounds, including amphetamines. For the first time, our studies have illustrated that there is an induction of TAAR1 mRNA expression in resting T lymphocytes in response to methamphetamine. Methamphetamine treatment for 6 h significantly increased TAAR1 mRNA expression (P < 0.001) and protein expression (P < 0.01) at 24 h. With the use of TAAR1 gene silencing, we demonstrate that methamphetamine-induced cAMP, a classic response to methamphetamine stimulation, is regulated via TAAR1. We also show by TAAR1 knockdown that the down-regulation of IL-2 in T cells by methamphetamine, which we reported earlier, is indeed regulated by TAAR1. Our results also show the presence of TAAR1 in human lymph nodes from HIV-1-infected patients, with or without a history of methamphetamine abuse. TAAR1 expression on lymphocytes was largely in the paracortical lymphoid area of the lymph nodes with enhanced expression in lymph nodes of HIV-1-infected methamphetamine abusers rather than infected-only subjects. In vitro analysis of HIV-1 infection of human PBMCs revealed increased TAAR1 expression in the presence of methamphetamine. In summary, the ability of methamphetamine to activate trace TAAR1 in vitro and to regulate important T cell functions, such as cAMP activation and IL-2 production; the expression of TAAR1 in T lymphocytes in peripheral lymphoid organs, such as lymph nodes; and our in vitro HIV-1 infection model in PBMCs suggests that TAAR1 may play an important role in methamphetamine -mediated immune-modulatory responses.

  17. Enhanced function of cytotoxic T lymphocytes induced by dendritic cells modified with truncated PSMA and 4-1BBL.

    PubMed

    Youlin, Kuang; Li, Zhang; Xin, Gou; Mingchao, Xiao; Xiuheng, Liu; Xiaodong, Weng

    2013-04-01

    Interactions between costimulatory molecules and their receptors are vital for Ag-presenting dendritic cells (DCs) to initiate T cells activation, expansion and their antitumor immune responses. Augmentation of costimulatory signal due to the interaction of DCs and T cells may amplify, sustain and drive diversity of cytotoxic T lymphocytes (CTLs) and consequently enhance the antitumor response. 4-1BBL/4-1BB is such a pair of costimulatory ligand and receptor, playing an important role in the co-stimulation of CTLs. Previously, we demonstrated that DCs transduced with recombinant adenovirus encoding truncated PSMA (tPSMA) and m4-1BBL could induce prostate cancer regression in mouse models. In the present study, we further explored the adjuvant role of 4-1BBL in modulating CTLs activation induced by tPSMA gene-pulsed DCs. The apoptosis and cytotoxicity against tPSMA expressing RM-1 cells of CTLs were determined. Results showed that tPSMA gene-pulsed DCs effectively induced T lymphocyte activation and cytotoxicity, which was enhanced by upregulated expression of 4-1BBL, displaying better cell viability, lower CTLs apoptosis, higher expression anti-apoptotic protein of Bcl-xL and phosphorylation of P38, enhanced NF-κB activation, as well as more IFN-γ production. These results demonstrated that 4-1BBL may play a significant role in the co-stimulation pathway for Ag-presenting DCs-mediated CTLs activity, which might be a beneficial adjuvant factor for DCs-based cancer immunotherapy.

  18. Distribution of HIV-1 Infection in Different T Lymphocyte Subsets: Antiretroviral Therapy-Naïve vs. Experienced Patients

    PubMed Central

    Perez, Raul; Gibson, Sonia; Lopez, Pablo; Koenig, Ellen; De Castro, Marisol

    2011-01-01

    Abstract Memory CD4 T cells are the primary targets of HIV-1 infection, which then subsequently spreads to other T lymphocyte subsets. Antiretroviral therapy (ART) alters the pattern of HIV-1 distribution. Blood samples were collected from ART-naïve or -experienced HIV-1 patients, and the memory and naïve subsets of CD4+ and CD8+ T lymphocytes, respectively, were isolated by cell sorting. DNA was extracted and the HIV-1 env C2/V3 region PCR amplified. Amplicons were cloned and sequenced, and genetic relatedness among different HIV-1 compartments was determined by the phylogenetic analysis of clonal sequences. The viral V3 sequence of HIV-1 in each compartment was analyzed by using webPSSM to determine CCR5 or CXCR4 coreceptor binding property of the virus. The direction of viral migration among involved compartments was determined by using the MacClade program. In ART-naïve patients, HIV-1 was generally confined to the memory CD4 T (mT4) cell compartment, even though in a few cases, naïve CD4 T (nT4) cells were also infected. When this occurred, the HIV-1 gene migrated from nT4 to mT4. In contrast, HIV-1 was detected in nT4 and mT4 as well as in the memory CD8 T (mT8) compartments of ART-experienced patients. However, no clear pattern of directional HIV-1 gene flow among the compartments could be determined because of the small sample size. All HIV-1–infected T cell compartments housed the virus that used either CCR5 or CXCR4 as the coreceptor. PMID:21054214

  19. Differential regulation of SOCS-1 signalling in B and T lymphocytes by hepatitis C virus core protein

    PubMed Central

    Yao, Zhi Qiang; Prayther, Deborah; Trabue, Christopher; Dong, Zhi Ping; Moorman, Jonathan

    2008-01-01

    Hepatitis C virus (HCV) infection is characterized by a strong propensity toward chronicity, autoimmune phenomena and lymphomagenesis, supporting a role for lymphocyte dysregulation during persistent viral infection. We have shown that HCV core protein inhibits T-cell functions through interaction with a complement receptor, gC1qR. Here, we further report that B cells also express gC1qR that can be bound by HCV core protein. Importantly, using flow cytometry, we demonstrated differential regulation of B and T lymphocytes by the HCV core–gC1qR interaction, with down-regulation of CD69 activation in T cells but up-regulation of CD69 activation and cell proliferation in B cells. HCV core treatment led to decreased interferon-γ production in CD8+ T cells but to increased immunoglobulin M and immunoglobulin G production as well as cell surface expression of costimulatory and chemokine receptors, including CD86 (B7-2), CD154 (CD40L) and CD195 (CCR5), in CD20+ B cells. Finally, we showed down-regulation of suppressor of cytokine signalling-1 (SOCS-1) using real-time reverse transcription–polymerase chain reaction, accompanied by up-regulation of signal transducer and activator of transcription-1 (STAT1) phosphorylation in B cells in response to HCV core protein, with the opposite pattern observed in HCV core-treated T cells. This study demonstrates differential regulation of B and T lymphocytes by HCV core and supports a mechanism by which lymphocyte dysregulation occurs in the course of persistent HCV infection. PMID:18397267

  20. Colorectal mucus binds DC-SIGN and inhibits HIV-1 trans-infection of CD4+ T-lymphocytes.

    PubMed

    Stax, Martijn J; Mouser, Emily E I M; van Montfort, Thijs; Sanders, Rogier W; de Vries, Henry J C; Dekker, Henk L; Herrera, Carolina; Speijer, Dave; Pollakis, Georgios; Paxton, William A

    2015-01-01

    Bodily secretions, including breast milk and semen, contain factors that modulate HIV-1 infection. Since anal intercourse caries one of the highest risks for HIV-1 transmission, our aim was to determine whether colorectal mucus (CM) also contains factors interfering with HIV-1 infection and replication. CM from a number of individuals was collected and tested for the capacity to bind DC-SIGN and inhibit HIV-1 cis- or trans-infection of CD4+ T-lymphocytes. To this end, a DC-SIGN binding ELISA, a gp140 trimer competition ELISA and HIV-1 capture/ transfer assays were utilized. Subsequently we aimed to identify the DC-SIGN binding component through biochemical characterization and mass spectrometry analysis. CM was shown to bind DC-SIGN and competes with HIV-1 gp140 trimer for binding. Pre-incubation of Raji-DC-SIGN cells or immature dendritic cells (iDCs) with CM potently inhibits DC-SIGN mediated trans-infection of CD4+ T-lymphocytes with CCR5 and CXCR4 using HIV-1 strains, while no effect on direct infection is observed. Preliminary biochemical characterization demonstrates that the component seems to be large (>100kDa), heat and proteinase K resistant, binds in a α1-3 mannose independent manner and is highly variant between individuals. Immunoprecipitation using DC-SIGN-Fc coated agarose beads followed by mass spectrometry indicated lactoferrin (fragments) and its receptor (intelectin-1) as candidates. Using ELISA we showed that lactoferrin levels within CM correlate with DC-SIGN binding capacity. In conclusion, CM can bind the C-type lectin DC-SIGN and block HIV-1 trans-infection of both CCR5 and CXCR4 using HIV-1 strains. Furthermore, our data indicate that lactoferrin is a DC-SIGN binding component of CM. These results indicate that CM has the potential to interfere with pathogen transmission and modulate immune responses at the colorectal mucosa.

  1. Immune privilege and FasL: two ways to inactivate effector cytotoxic T lymphocytes by FasL-expressing cells

    PubMed Central

    Li, Jie-Hui; Rosen, Dalia; Sondel, Paul; Berke, Gideon

    2002-01-01

    The theory that Fas ligand (FasL)-expressing tumours are immune-privileged and can directly counterattack Fas-expressing effector T lymphocytes has recently been questioned and several alternative mechanisms have been proposed. To address this controversial issue, we analysed the impact of FasL-expressing tumours on in vivo-primed cytotoxic T lymphocytes (CTLs) and the mechanisms involved. CTLs were obtained from the peritoneal cavity (PEL) after in vivo priming with syngeneic or allogeneic murine tumour cells. We have found that PEL populations undergo Fas-based apoptotic cell death when co-cultured with FasL-expressing tumour cells and that PEL destruction of cognate targets in a 51Cr-release assay was markedly inhibited by the pre-exposure to either cognate or non-cognate tumour cells expressing FasL. Furthermore, cytocidal function of PEL was markedly inhibited by preincubation with FasL-negative tumour cells, if and only if they were the cognate targets of the CTL; this CTL inhibition involved FasL–Fas interactions. The killing function of ‘bystander’ PELs, reactive to a third-party target cell, was inhibited by co-cultivation with PELs mixed with their cognate target. This activation-induced CTL fratricide was not influenced by the expression of FasL on the cognate target cells. These studies demonstrate the existence of two distinct pathways whereby FasL-expressing cells inhibit in vivo-primed FasL- and Fas-expressing CTLs: first, by FasL-based direct tumour counterattack, and second, by FasL-mediated activation-induced cell death of the CTLs, which is consistent with the concept that FasL expression in vivo could play a role in inducing immune privilege. PMID:11918688

  2. Antigenicity and immunogenicity of multiple antigen peptides (MAP) containing P. vivax CS epitopes in Aotus monkeys.

    PubMed

    Herrera, S; De Plata, C; González, M; Perlaza, B L; Bettens, F; Corradin, G; Arévalo-Herrera, M

    1997-04-01

    Using linear synthetic peptides corresponding to the Plasmodium vivax circumsporozoite (CS) protein of the common type, we have identified several T and B-cell epitopes recognized by human individuals. Three T-cell epitopes studied (p6) from the amino, (p11) from the central and (p25) from the carboxyl regions, were widely recognized by lymphocytes of immune donors. A series of six peptides, in addition to p11, representing the central repeat domain of the CS(p11-p17) protein were used in ELISA assays to map the B-cell epitopes of this region. P11 was the peptide most frequently recognized by sera containing antibodies to the homologous CS protein as determined by IFAT. The sequences corresponding to peptides p6, p11 and P25 as well as that representing a universal T-cell epitope derived from the tetanus toxin were used to assemble eight different Multiple Antigen Peptides (MAP). The immunogenicity of these MAP was analysed in Aotus monkeys. Groups of two animals were immunized with each MAP and both antibody response, T-lymphocyte proliferation and in vitro gamma-IFN production were evaluated. Two MAPs containing the same B-cell epitope and either a promiscuous CS-protein derived T-cell epitope (p25) or the tetanus toxin epitope (p-tt30) proved to be the most immunogenic and induced high levels of anti-peptide antibodies that recognized the native protein. Except for animals immunized with MAP VII, there was no correlation between antibody levels, lymphocyte proliferation or gamma-IFN production in vitro. The broad recognition of these epitopes by individuals which had been exposed to malaria, the capacity of these MAPs to induce antibodies, recognize the cognate protein, and in vitro gamma-IFN production encourages further analyses of the potential of these proteins as malaria vaccine candidates for human use.

  3. Rapid tumor regression in an Asian lung cancer patient following personalized neo-epitope peptide vaccination

    PubMed Central

    Li, Fenge; Chen, Caixia; Ju, Tao; Gao, Junqin; Yan, Jun; Wang, Peng; Xu, Qiang; Hwu, Patrick; Du, Xueming; Lizée, Gregory

    2016-01-01

    ABSTRACT Personalized immunotherapy targeting tumor-specific mutations represents a highly promising approach to cancer treatment. Here, we describe an Asian lung squamous cell carcinoma patient demonstrating frank disease progression following chemotherapy and EGFR inhibitor treatment. Based on tumor mutational profiling and HLA typing, a saline-based multi-epitope peptide vaccine was designed and administered along with topical imiquimod as an adjuvant. Weekly neo-epitope peptide vaccination was followed by a rapid and dramatic regression of multiple lung tumor nodules, while a much larger liver metastasis remained refractory to treatment. Peripheral blood immune monitoring showed that specific cytotoxic T lymphocytes (CTLs) were induced primarily against peptide targets encompassing the widely shared EGFR L858R mutation, particularly one restricted to HLA-A*3101. Immunological targeting of this driver mutation may be of particular benefit to Asian lung cancer patients due to its relatively high prevalence within this patient population. PMID:28123873

  4. The development of in vitro mutagenicity testing systems using T-lymphocytes. Research progress report, November 1, 1992--October 31, 1993

    SciTech Connect

    Albertini, R.J.

    1993-05-01

    This annual report describes progress in studies on hprt mutations induced by radon or Indium 111 along with the corresponding mutation frequency, cloning and molecular spectra in human T-lymphocytes. Parallel studies on the mutation susceptibility between individuals is being investigated by hprt mutation studies on ataxia telangiectasia and xeroderma pigmentosum.

  5. Cross reactive antibody and cytotoxic T lymphocytes from avian influenza H9N2 infected chickens against homologous and heterologous avian influenza isolates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunity against avian influenza (AI) is largely based on the induction of neutralizing antibodies produced against the hemagglutinin, although cytotoxic T lymphocytes (CTL’s) have been reported as critical for clearance of virus from infected cells. Antibody production against a particular virus ...

  6. Characterization of circulating CD4(+) CD8(+) double positive and CD4(-) CD8(-) double negative T-lymphocyte in children with β-thalassemia major.

    PubMed

    Zahran, Asmaa M; Saad, Khaled; Elsayh, Khalid I; Alblihed, Mohamd A

    2017-03-01

    Infectious complications represent the second most common cause of mortality and a major cause of morbidity in β-thalassemia major (BTM), with a prevalence of 12-13%. The data on unconventional T-lymphocyte subsets in BTM children are limited. The aim of the present study was to investigate and evaluate phenotypic alterations in CD4(+)CD8(+) double positive (DP), CD4(-) CD8(-) double negative (DN), and natural killer T-lymphocytes (NKT) in BTM children in comparison to healthy controls. Our case control study included 80 children with BTM and 40 healthy children as controls. Assessment of unconventional T-lymphocyte populations was done using sensitive four-color flow cytometry (FACSCalibur). Our analysis of the data showed a significantly higher frequency CD4(+) CD8(+) (double-positive) T cells, CD4(-) CD8(-) (double negative) T cells, and natural killer T cells in the peripheral blood of both BTM groups (splenectomized and non-splenectomized) as compared to healthy controls, suggesting that these cells may play a role in the clinical course of BTM. The relationship of the unconventional T-lymphocytes to immune disorders in BTM children remains to be determined. Further longitudinal study with a larger sample size is warranted to elucidate the role these cells in BTM.

  7. Drug-induced modulation of T lymphocytes as a potential mechanism of susceptibility to infections in patients with multiple myeloma during bortezomib therapy.

    PubMed

    Li, Juan; Li, Ying; Huang, Beihui; Zheng, Dong; Chen, Mei; Zhou, Zhenhai

    2015-01-01

    Bortezomib is effective in the therapy of multiple myeloma (MM), but causes infections that are different from those associated with conventional chemotherapy. It is important to identify the risk factors that facilitate infections associated with bortezomib therapy. In the present report, we sought to (1) define the features of the infections associated with this therapy and (2) identify the immune mechanisms responsible for the observed susceptibility to these infections. We first retrospectively analyzed the clinical data of 143 patients who had received bortezomib therapy for MM. We then prospectively assessed the modulation of T lymphocyte status during this therapy, and evaluated potential relationships between infections and T lymphocyte changes. The infection rates peaked during the first cycle of bortezomib therapy (47.6%) in patients with MM (p < 0.05 vs. subsequent cycles). Bortezomib therapy was associated with higher incidence rates of viral and fungal infections (15.8%, p < 0.05 vs. conventional chemotherapy). In addition, patients with the IgG immunophenotype showed higher bacterial and viral infection rates (respectively, p = 0.008 and 0.009). The T lymphocyte numbers significantly decreased after bortezomib therapy (p < 0.05), and the same was true for the Th1/Th2 ratio (p < 0.01). Patients with MM who have decreased lymphocyte counts, while on bortezomib therapy are more likely to develop bacterial or viral infections. In addition, an imbalance in T lymphocyte subsets is also associated with bacterial or viral infections in these patients.

  8. Inhibition of clinical human immunodeficiency virus (HIV) type 1 isolates in primary CD4+ T lymphocytes by retroviral vectors expressing anti-HIV genes.

    PubMed Central

    Vandendriessche, T; Chuah, M K; Chiang, L; Chang, H K; Ensoli, B; Morgan, R A

    1995-01-01

    Gene therapy may be of benefit in human immunodeficiency virus type 1 (HIV-1)-infected individuals by virtue of its ability to inhibit virus replication and prevent viral gene expression. It is not known whether anti-HIV-1 gene therapy strategies based on antisense or transdominant HIV-1 mutant proteins can inhibit the replication and expression of clinical HIV-1 isolates in primary CD4+ T lymphocytes. We therefore transduced CD4+ T lymphocytes from uninfected individuals with retroviral vectors expressing either HIV-1-specific antisense-TAR or antisense-Tat/Rev RNA, transdominant HIV-1 Rev protein, and a combination of antisense-TAR and transdominant Rev. The engineered CD4+ T lymphocytes were then infected with four different clinical HIV-1 isolates. We found that replication of all HIV-1 isolates was inhibited by all the anti-HIV vectors tested. Greater inhibition of HIV-1 was observed with transdominant Rev than with antisense RNA. We hereby demonstrated effective protection by antisense RNA or transdominant mutant proteins against HIV-1 infection in primary CD4+ T lymphocytes using clinical HIV-1 isolates, and this represents an essential step toward clinical anti-HIV-1 gene therapy. PMID:7769662

  9. The Magnitude and Kinetics of the Mucosal HIV-Specific CD8+ T Lymphocyte Response and Virus RNA Load in Breast Milk

    PubMed Central

    Mahlokozera, Tatenda; Kang, Helen H.; Goonetilleke, Nilu; Stacey, Andrea R.; Lovingood, Rachel V.; Denny, Thomas N.; Kalilani, Linda; Bunn, James E. G.; Meshnick, Steve R.; Borrow, Persephone; Letvin, Norman L.; Permar, Sallie R.

    2011-01-01

    Background The risk of postnatal HIV transmission is associated with the magnitude of the milk virus load. While HIV-specific cellular immune responses control systemic virus load and are detectable in milk, the contribution of these responses to the control of virus load in milk is unknown. Methods We assessed the magnitude of the immunodominant GagRY11 and subdominant EnvKY9-specific CD8+ T lymphocyte response in blood and milk of 10 A*3002+, HIV-infected Malawian women throughout the period of lactation and correlated this response to milk virus RNA load and markers of breast inflammation. Results The magnitude and kinetics of the HIV-specific CD8+ T lymphocyte responses were discordant in blood and milk of the right and left breast, indicating independent regulation of these responses in each breast. However, there was no correlation between the magnitude of the HIV-specific CD8+ T lymphocyte response and the milk virus RNA load. Further, there was no correlation between the magnitude of this response and markers of breast inflammation. Conclusions The magnitude of the HIV-specific CD8+ T lymphocyte response in milk does not appear to be solely determined by the milk virus RNA load and is likely only one of the factors contributing to maintenance of low virus load in milk. PMID:21886819

  10. Relationship Between Radiation-Induced Apoptosis of T Lymphocytes and Chronic Toxicity in Patients With Prostate Cancer Treated by Radiation Therapy: A Prospective Study

    SciTech Connect

    Foro, Palmira; Algara, Manuel; Lozano, Joan; Rodriguez, Nuria; Sanz, Xavier; Torres, Erica; Carles, Joan; Reig, Anna; Membrive, Ismael; Quera, Jaume; Fernandez-Velilla, Enric; Pera, Oscar; Lacruz, Marti; Bellosillo, Beatriz

    2014-04-01

    Purpose: To assess the correlation of radiation-induced apoptosis in vitro of CD4 and CD8 T lymphocytes with late toxicity of prostate cancer patients treated with radiation therapy. Methods and Materials: 214 patients were prospectively included in the study. Peripheral blood was drawn from patients before treatment and irradiated with 8 Gy. The percentage of CD4+ and CD8+ T lymphocytes that underwent radiation-induced apoptosis was assessed by flow cytometry. Toxicity and mortality were correlated in 198 cases with pretreatment apoptosis and clinical and biological variables by use of a Cox proportional hazards model. Results: The mean percentage of CD4+ and CD8+ T lymphocyte radiation-induced apoptosis was 28.58% (±14.23) and 50.76% (±18.9), respectively. Genitourinary (GU) toxicity was experienced by 39.9% of patients, while gastrointestinal (GI) toxicity was experienced by 19.7%. The probability of development of GU toxicity was nearly doubled (hazard ratio [HR] 1.99, P=.014) in those patients in whom the percentage of in vitro radiation-induced apoptosis of CD4+ T-lymphocytes was ≤28.58%. It was also almost double in patients who received doses ≥50 Gy in 65% of the bladder volume (V65 ≥50) (HR 1.92, P=.048). No correlation was found between GI toxicity and any of the variables studied. The probability of death during follow-up, after adjustment for different variables, was 2.7 times higher in patients with a percentage of CD8+ T lymphocyte apoptosis ≤50.76% (P=.022). Conclusions: In conclusion, our study shows, in the largest prospective cohort of prostate cancer patients undergoing radiation therapy, that in vitro radiation-induced apoptosis of CD4+ T lymphocytes assessed before radiation therapy was associated with the probability of developing chronic GU toxicity. In addition, the radiation dose received in the urinary bladder (V65 ≥50) affected the occurrence of GU toxicity. Finally, we also demonstrate that radiation-induced apoptosis of

  11. Protective effect of deoxyribonucleosides on UV-irradiated human peripheral blood T-lymphocytes: possibilities for the selective killing of either cycling or non-cycling cells.

    PubMed

    Green, M H; Waugh, A P; Lowe, J E; Harcourt, S A; Clingen, P H; Cole, J; Arlett, C F

    1996-02-19

    Non-cycling human T-lymphocytes from normal subjects show a 10-fold greater sensitivity than fibroblasts to UV-B (280-315 nm) irradiation from a Westinghouse FS20 lamp, but only a 2.7-fold greater sensitivity to UV-C (254 nm) irradiation. Hypersensitivity is associated with a deficiency in the rejoining of excision breaks. Non-cycling T-lymphocytes have extremely low deoxyribonucleotide pools. Addition to the medium of the four deoxyribonucleosides, each at a concentration of 10(-5) M, substantially increases survival and reduces the persistence of excision-related strand breaks following UV-B or UV-C irradiation (Yew and Johnson (1979) Biochim. Biophys. Acta 562, 240-241; Green et al. (1994) Mutation Res., 315, 25-32). UV-resistance of T-lymphocytes is also increased by stimulating the cells into cycle. The addition of deoxyribonucleosides does not further enhance survival of cycling cells and they do not reach the level of resistance achieved by non-cycling cells in the presence of deoxyribonucleosides. We suggest that two opposing effects are in operation. Cells out of cycle can show increased resistance to DNA damage in the absence of division but they also have reduced deoxyribonucleotide pools, which may limit DNA repair. With UV-B irradiation, the exceptionally low dNTP pools in non-cycling T-lymphocytes cause this second effect to predominate. In contrast, with ionising radiation, which forms highly cytotoxic double-strand breaks, non-cycling human T-lymphocytes are slightly more resistant than fibroblasts. Non-cycling cells such as T-lymphocytes should be especially sensitive to agents which produce a high proportion of read excisable damage, but should show normal resistance to agents which highly toxic lesions. It may be possible by choice of DNA damaging agent and manipulation of cellular deoxyribonucleotide pools, to choose regimes which will selectively kill either cycling or non-cycling cells and to improve the efficacy of standard therapeutic

  12. Pro-inflammatory chemokine-chemokine receptor interactions within the Ewing sarcoma microenvironment determine CD8(+) T-lymphocyte infiltration and affect tumour progression.

    PubMed

    Berghuis, Dagmar; Santos, Susy J; Baelde, Hans J; Taminiau, Antonie Hm; Egeler, R Maarten; Schilham, Marco W; Hogendoorn, Pancras Cw; Lankester, Arjan C

    2011-02-01

    Ewing sarcoma is an aggressive round cell sarcoma with poor patient prognosis, particularly in cases of advanced-stage disease. Dynamic tumor-host immune interations within the tumor microenvironment may polarize in situ immune responses and shape tumor development and/or progression. To gain insight into the nature of tumour-host immune interactions within the Ewing sarcoma microenvironment, the presence and spatial distribution of infiltrating CD8(+) /CD4(+) T-lymphocytes were evaluated in therapy-naive Ewing sarcoma. Expression profiling of 40 different chemokines and several chemokine receptors was performed in therapy-naive tumours and cell lines by qPCR, immunohistochemistry, and flow cytometry. Considerable inter-tumour variation was observed regarding density, type, and distribution of infiltrating T-lymphocytes. Tumour-infiltrating T-cells contained significantly higher percentages of CD8(+) T-lymphocytes as compared to stroma-infiltrating cells, suggesting preferential migration of this T-cell type into tumour areas. Gene expression levels of several type 1-associated, pro-inflammatory chemokines (CXCR3- and CCR5-ligands CXCL9, CXCL10, and CCL5) correlated positively with infiltrating (CD8(+) ) T-lymphocyte numbers expressing corresponding chemokine receptors. Survival analyses demonstrated an impact of tumour-infiltrating, and not stroma-infiltrating, CD8(+) T-lymphocytes on tumour progression. At protein level, both tumour and stromal cells expressed the IFNγ-inducible chemokines CXCL9 and CXCL10. CCR5-ligand CCL5 was exclusively expressed by non-tumoural stromal/infiltrating cells. Together, our results indicate that an inflammatory immune microenvironment with high expression of type 1-associated chemokines may be critical for the recruitment of (CD8(+) ) T-lymphocytes expressing corresponding chemokine receptors. The observed impact of tumour-infiltrating (CD8(+) ) T-lymphocytes is consistent with a role for adaptive anti-tumour immunity in the

  13. Mechanisms responsible for defective human T-lymphocyte sheep erythrocyte rosette function associated with hepatitis B virus infections.

    PubMed Central

    Chisari, F V; Routenberg, J A; Edgington, T S

    1976-01-01

    The expression of selected lymphocyte surface-membrane markers was evaluated in 37 patients with acute viral hepatitis B, 10 of whom were studied serially through the resolving and convalescent phases of disease. Bone marrow-derived (B) lymphocytes were identified by reference to surface immunoglobulin, whereas normal thymus-derived (T) lymphocytes were assayed by their capacity to form spontaneous nonimmune rosettes with sheep erythrocytes (E rosettes, ER). During the acute and resolving phases of viral hepatitis B, the relative and absolute number of ER-positive lymphocytes was significantly reduced, whereas the number of surface immunoglobulin-positive lymphocytes and the absolute lymphocyte count remained normal. This resulted in the appearance of a third population of cells, deficient in respect to both surface immunoglobulin and ER markers. Such cells accounted for nearly 25% of peripheral blood lymphocytes, approximately 5 x 105ml blood. Depression of the number of ER-positive lymphocytes occurred at least once during the course of disease in every patient studied serially, and was observed in 55 of 67 individual assays of the 37 cases of acute viral hepatitis B. Lymphocytes from some patients reacquired ER function when cultured in fetal calf serum but not in the presence of autologous serum. Such autologous serum was capable of suppressing ER function of lymphocytes from normal donors. The extrinsic suppression of er function by a serum factor (designated as the Rosette Inhibitory Factor), was found to be time dependent, characterized by a 4-h latent period and requiring approximately 18 h for maximum attenuation of ER function. The Serum Rosette Inhibitory Factor was: (a) heat and freeze-thaw stable, (b) nondialyzable, (c) physically separable from hepatitis B surface antigen, (d) not a lymphocytotoxic antibody, and (e) had the buoyant density of a lipoprotein. This extrinsic mechanism was observed in 41.8% of patients with reduced numbers of ER

  14. Epitope peptides and immunotherapy.

    PubMed

    Tanabe, Soichi

    2007-02-01

    Allergic diseases affect atopic individuals, who synthesize specific Immunoglobulins E (IgE) to environmental allergens, usually proteins or glycoproteins. These allergens include grass and tree pollens, indoor allergens such as house dust mites and animal dander, and various foods. Because allergen-specific IgE antibodies are the main effector molecules in the immune response to allergens, many studies have focused on the identification of IgE-binding epitopes (called B cell epitopes), specific and minimum regions of allergen molecules that binds to IgE. Our initial studies have provided evidence that only four to five amino acid residues are enough to comprise an epitope, since pentapeptide QQQPP in wheat glutenin is minimally required for IgE binding. Afterwards, various kinds of B cell epitope structures have been clarified. Such information contributes greatly not only to the elucidation of the etiology of allergy, but also to the development of strategies for the treatment and prevention of allergy. Allergen-specific T cells also play an important role in allergy and are obvious targets for intervention in the disease. Currently, the principle approach is to modify B cell epitopes to prevent IgE binding while preserving T cell epitopes to retain the capacity for immunotherapy. There is mounting evidence that the administration of peptide(s) containing immunodominant T cell epitopes from an allergen can induce T cell nonresponsiveness (immunotherapy). There have been clinical studies of peptide immunotherapy performed, the most promising being for bee venom sensitivity. Clinical trials of immunotherapy for cat allergen peptide have also received attention. An alternative strategy for the generation of an effective but hypoallergenic preparation for immunotherapy is to modify T cell epitope peptides by, for example, single amino acid substitution. In this article, I will present an overview of epitopes related to allergic disease, particularly stress on

  15. Aminobisphosphonates prevent the inhibitory effects exerted by lymph node stromal cells on anti-tumor Vδ 2 T lymphocytes in non-Hodgkin lymphomas.

    PubMed

    Musso, Alessandra; Catellani, Silvia; Canevali, Paolo; Tavella, Sara; Venè, Roberta; Boero, Silvia; Pierri, Ivana; Gobbi, Marco; Kunkl, Annalisa; Ravetti, Jean-Louis; Zocchi, Maria Raffaella; Poggi, Alessandro

    2014-01-01

    In this study, we analyzed the influence of mesenchymal stromal cells derived from lymph nodes of non-Hodgkin's lymphomas, on effector functions and differentiation of Vdelta (δ)2 T lymphocytes. We show that: i) lymph-node mesenchymal stromal cells of non-Hodgkin's lymphoma inhibit NKG2D-mediated lymphoid cell killing, but not rituximab-induced antibody-dependent cell-mediated cytotoxicity, exerted by Vδ2 T lymphocytes; ii) pre-treatment of mesenchymal stromal cells with the aminobisphosphonates pamidronate or zoledronate can rescue lymphoma cell killing via NKG2D; iii) this is due to inhibition of transforming growth factor-β and increase in interleukin-15 production by mesenchymal stromal cells; iv) aminobisphosphonate-treated mesenchymal stromal cells drive Vδ2 T-lymphocyte differentiation into effector memory T cells, expressing the Thelper1 cytokines tumor necrosis factor-α and interferon-γ. In non-Hodgkin's lymphoma lymph nodes, Vδ2 T cells were mostly naïve; upon co-culture with autologous lymph-node mesenchymal stromal cells exposed to zoledronate, the percentage of terminal differentiated effector memory Vδ2 T lymphocytes increased. In all non-Hodgkin's lymphomas, low or undetectable transcription of Thelper1 cytokines was found. In diffused large B-cell lymphomas and in a group of follicular lymphoma, transcription of transforming growth factor β and interleukin-10 was enhanced compared to non-neoplastic lymph nodes. Thus, in non-Hodgkin lymphomas mesenchymal stromal cells interfere with Vδ2 T-lymphocyte cytolytic function and differentiation to Thelper1 and/or effector memory cells, depending on the prominent in situ cytokine milieu. Aminobisphosphonates, acting on lymph-node mesenchymal stromal cells, can push the balance towards Thelper1/effector memory and rescue the recognition and killing of lymphoma cells through NKG2D, sparing rituximab-induced antibody-dependent cell-mediated cytotoxicity.

  16. Differential changes in CD4+ and CD8+ effector and regulatory T lymphocyte subsets in the testis of rats undergoing autoimmune orchitis.

    PubMed

    Jacobo, P; Guazzone, V A; Jarazo-Dietrich, S; Theas, M S; Lustig, L

    2009-07-01

    Experimental autoimmune orchitis (EAO) is a useful model to study organ-specific autoimmunity and chronic testicular inflammation. EAO is characterized by an interstitial lymphomononuclear cell infiltration and damage of the seminiferous tubules showing germ cell sloughing and apoptosis. Using flow cytometry, we analysed the phenotype and number of T lymphocytes present in the testicular interstitium of rats during EAO development. A large increase in the number of testicular CD3+ T lymphocytes was detected. The number of CD4+ and CD8+ effector T lymphocytes (T(effector) cells) dramatically increased in the testis at EAO onset, with the CD4+ cell subset predominating. As the severity of the disease progressed, CD4+ T(effector) cells declined in number while the CD8+ T(effector) cell subset remained unchanged, suggesting their involvement in maintenance of the chronic phase of EAO. As a novel finding, we detected by immunohistochemistry and flow cytometry Foxp3 expressing CD4+ and CD8+ regulatory T lymphocytes (T(regs)) in chronically inflamed testis of EAO rats. The numbers of both T(reg) cell subsets increased in the testis of rats with orchitis, mainly at the onset of EAO; CD4+Foxp3+ T(reg) cells were more abundant than CD8+Foxp3+ T(reg) cells. Unexpectedly, CD25- T lymphocytes were more abundant than CD25+ cells within CD4+Foxp3+ and CD8+Foxp3+ T(reg) cell populations. Although T(reg) subsets are actively accumulated into the testis in EAO rats, these cells are outnumbered by an even more vigorously expanding T(effector) subset. Further, it is possible that factors present in the inflamed testis might limit the ability of T(regs) to abrogate tissue damage.

  17. Curcumin blocks interleukin (IL)-2 signaling in T-lymphocytes by inhibiting IL-2 synthesis, CD25 expression, and IL-2 receptor signaling

    SciTech Connect

    Forward, Nicholas A.; Conrad, David M.; Power Coombs, Melanie R.; Doucette, Carolyn D.; Furlong, Suzanne J.; Lin, Tong-Jun; Hoskin, David W.

    2011-04-22

    Highlights: {yields} Curcumin inhibits CD4{sup +} T-lymphocyte proliferation. {yields} Curcumin inhibits interleukin-2 (IL-2) synthesis and CD25 expression by CD4{sup +} T-lymphocytes. {yields} Curcumin interferes with IL-2 receptor signaling by inhibiting JAK3 and STAT5 phosphorylation. {yields} IL-2-dependent regulatory T-lymphocyte function and Foxp3 expression is downregulated by curcumin. -- Abstract: Curcumin (diferulomethane) is the principal curcuminoid in the spice tumeric and a potent inhibitor of activation-induced T-lymphocyte proliferation; however, the molecular basis of this immunosuppressive effect has not been well studied. Here we show that micromolar concentrations of curcumin inhibited DNA synthesis by mouse CD4{sup +} T-lymphocytes, as well as interleukin-2 (IL-2) and CD25 ({alpha} chain of the high affinity IL-2 receptor) expression in response to antibody-mediated cross-linking of CD3 and CD28. Curcumin acted downstream of protein kinase C activation and intracellular Ca{sup 2+} release to inhibit I{kappa}B phosphorylation, which is required for nuclear translocation of the transcription factor NF{kappa}B. In addition, IL-2-dependent DNA synthesis by mouse CTLL-2 cells, but not constitutive CD25 expression, was impaired in the presence of curcumin, which demonstrated an inhibitory effect on IL-2 receptor (IL-2R) signaling. IL-2-induced phosphorylation of STAT5A and JAK3, but not JAK1, was diminished in the presence of curcumin, indicating inhibition of critical proximal events in IL-2R signaling. In line with the inhibitory action of curcumin on IL-2R signaling, pretreatment of CD4{sup +}CD25{sup +} regulatory T-cells with curcumin downregulated suppressor function, as well as forkhead box p3 (Foxp3) expression. We conclude that curcumin inhibits IL-2 signaling by reducing available IL-2 and high affinity IL-2R, as well as interfering with IL-2R signaling.

  18. Group I mGlu receptor stimulation inhibits activation-induced cell death of human T lymphocytes

    PubMed Central

    Chiocchetti, Annalisa; Miglio, Gianluca; Mesturini, Riccardo; Varsaldi, Federica; Mocellin, Marco; Orilieri, Elisabetta; Dianzani, Chiara; Fantozzi, Roberto; Dianzani, Umberto; Lombardi, Grazia

    2006-01-01

    The effects of L-glutamate on activation-induced cell death (AICD) of human activated (1 μg ml−1 phytohemagglutinin plus 2 U ml−1 interleukin-2; 8 days) T lymphocytes were studied by measuring anti-CD3 monoclonal antibody (10 μg ml−1; 18 h)-induced cell apoptosis (Annexin V and propidium iodide staining). L-Glutamate (1 × 10−8–1 × 10−4 M) significantly (P⩽0.01) inhibited AICD in a concentration-dependent manner (EC50=6.3 × 10−8 M; maximum inhibition 54.8±6.3% at 1 × 10−6 M). The L-glutamate inhibitory effect was pharmacologically characterized as mediated by group I mGlu receptors, since mGlu receptor agonists reproduced this effect. The EC50 values were: 3.2 × 10−7 M for (1S,3R)-ACPD; 4.5 × 10−8 M for quisqualate; 1.0 × 10−6 M for (S)-3,5-DHPG; 2.0 × 10−5 M for CHPG. Group I mGlu receptor antagonists inhibited the effects of quisqualate 1.0 × 10−6 M. The IC50 values calculated were: 8.7 × 10−5, 4.3 × 10−6 and 6.3 × 10−7 M for AIDA, LY 367385 and MPEP, respectively. L-Glutamate (1 × 10−6 M; 18 h) significantly (P⩽0.05) inhibited FasL expression (40.8±11.3%) (cytofluorimetric analysis), whereas it did not affect Fas signalling. Expression of both mGlu1 and mGlu5 receptor mRNA by T lymphocytes and T-cell lines, as demonstrated by reverse transcriptase–PCR analysis, suggests that L-glutamate-mediated inhibition of AICD was exerted on T cells. These data depict a novel role for L-glutamate in the regulation of the immune response through group I mGlu receptor-mediated mechanisms. PMID:16751798

  19. Hepatitis B virus surface antigen as delivery vector can enhance Chlamydia trachomatis MOMP multi-epitope immune response in mice.

    PubMed

    Zhu, Shanli; Feng, Yan; Rao, Pinhuan; Xue, Xiangyang; Chen, Shao; Li, Wenshu; Zhu, Guanbao; Zhang, Lifang

    2014-05-01

    Chlamydia trachomatis is the leading cause of sexually transmitted infections worldwide. There is currently no commercially available vaccine against C. trachomatis. Major outer membrane protein (MOMP) of C. trachomatis is considered to be an ideal candidate for prophylactic vaccine. We designed a MOMP multi-epitope containing T- and B-cell epitope-rich peptides and developed hepatitis B surface antigen (HBsAg) as antigen delivery vehicle. In order to study the immunogenicity and efficacy of the candidate vaccine in a murine model of chlamydial genital infection, we engineered a recombinant plasmid expressing HBsAg and MOMP multi-epitope genes. Results of reverse transcription polymerase chain reaction and immunofluorescence assay revealed successful expression of the recombinant HBsAg/MOMP multi-epitope gene at both the transcription and translation levels. Intramuscular administration in mice was able to elicit not only antibodies against Chlamydia and HBsAg but also cytotoxic T lymphocyte activity against Chlamydia. In addition, mice inoculated with the rHBsAg were highly resistant to C. trachomatis genital infection. The rHBsAg DNA with MOMP multi-epitope appended at the C terminus of the HBsAg stimulated a stronger immune response and protective response than that appended at the N terminus. Together, our results suggested that use of a recombinant HBsAg encoding the MOMP multi-epitope could be a powerful approach to developing a safe and immunogenic C. trachomatis vaccine.

  20. Functional Alteration of Natural Killer Cells and Cytotoxic T Lymphocytes upon Asbestos Exposure and in Malignant Mesothelioma Patients.

    PubMed

    Nishimura, Yasumitsu; Kumagai-Takei, Naoko; Matsuzaki, Hidenori; Lee, Suni; Maeda, Megumi; Kishimoto, Takumi; Fukuoka, Kazuya; Nakano, Takashi; Otsuki, Takemi

    2015-01-01

    Malignant mesothelioma is caused by exposure to asbestos, which is known to have carcinogenic effects. However, the development of mesothelioma takes a long period and results from a low or intermediate dose of exposure. These findings have motivated us to investigate the immunological effects of asbestos exposure and analyze immune functions of patients with mesothelioma and pleural plaque, a sign of exposure to asbestos. Here, we review our knowledge concerning natural killer (NK) cells and cytotoxic T lymphocytes (CTL). NK cells showed impaired cytotoxicity with altered expression of activating receptors upon exposure to asbestos, while induction of granzyme(+) cells in CD8(+) lymphocytes was suppressed by asbestos exposure. It is interesting that a decrease in NKp46, a representative activating receptor, is common between NK cells in PBMC culture with asbestos and those of mesothelioma patients. Moreover, it was observed that CD8(+) lymphocytes may be stimulated by some kind of "nonself" cells in plaque-positive individuals and in mesothelioma patients, whereas CTL in mesothelioma is impaired by poststimulation maintenance of cytotoxicity. These findings suggest that analysis of immunological parameters might contribute to the evaluation of health conditions of asbestos-exposed individuals and to a greater understanding of the pathology of malignant mesothelioma.

  1. Predominant expression of Fas ligand mRNA in CD8+ T lymphocytes in patients with HTLV-1 associated myelopathy.

    PubMed

    Kawahigashi, N; Furukawa, Y; Saito, M; Usuku, K; Osame, M

    1998-10-01

    To determine if Fas ligand (FasL) mediated apoptosis is involved in the pathogenesis of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), we examined the expression of FasL mRNA in fresh uncultured peripheral blood mononuclear cells (PBMC) from 17 Japanese patients with HAM/TSP, four adult T-cell leukemia/lymphoma (ATL) patients, three asymptomatic HTLV-1 carriers and three normal individuals. Using competitive PCR with primers specific for FasL mRNA, we demonstrated that nine of 17 HAM/TSP and one of four ATL patients expressed significant levels of FasL mRNA, whereas asymptomatic carriers, normal controls and both HTLV-1 infected and uninfected T-cell lines did not. Cell separation analysis following PCR revealed that FasL mRNA was expressed in CD8 + T lymphocytes. FasL mRNA was preferentially expressed in patients with increased proviral load and longer duration of clinical illness. These results suggest that FasL mediated mechanisms contribute to the pathogenesis of HAM/TSP.

  2. Inhibitory effects of various oxygenated sterols on the differentiation and function of tumor-specific cytotoxic T lymphocytes

    SciTech Connect

    Spangrude, G.J.; Sherris, D.; Daynes, R.A.

    1982-05-01

    Irradiation of skin with ultraviolet light (UVL) is capable of causing many biological and biochemical changes in this complex organ. One early consequence is the oxidation of epidermal plasma membrane cholesterol, causing the induction of a wide variety of photoproducts. It is well recognized that some oxygenated sterols possess potent biological activity on mammalian cells by their ability to inhibit endogeneous mevalonate and cholesterol biosynthesis. In the few immunological systems that have been studied, there is general agreement that lymphocyte function is altered in the presence of certain oxygenated sterols. Insight into the biochemical basis for altered lymphocyte function is lacking, as both afferent and efferent blockades have been suggested. These studies were undertaken to determine the effect of various oxygenated sterols (representing a number of known cholesterol-derived photoproducts) on the generation (afferent) and function (efferent) of cytotoxic T lymphocytes (CTLs). Cell-mediated immune responses which result in the generation of both alloantigen-specific and syngeneic tumor-specific CTLs were evaluated. (JMT)

  3. HIV-mediated immunodepression: in vitro inhibition of T-lymphocyte proliferative response by ultraviolet-inactivated virus

    SciTech Connect

    Amadori, A.; Faulkner-Valle, G.P.; De Rossi, A.; Zanovello, P.; Collavo, D.; Chieco-Bianchi, L.

    1988-01-01

    In order to assess whether the human retrovirus HIV, like other animal retroviruses, is endowed with intrinsic immunosuppressive activity, we studied the effects of noninfectious, uv-irradiated virus on in vitro lymphocyte function. uvHIV preparations inhibited T-cell proliferation to mitogens and alloantigens, as well as mitogen-driven IL-2 production. The inhibitory effect, which was not exerted by uv-irradiated HTLV-I, was apparently not due to a decrease in cell viability and was likely associated with thermoresistant viral component(s). The suppression proved to be selective for T-cell responses, while sparing other lymphocyte functions, such as the B-cell proliferative response to a selective B-cell mitogen. The inhibitory effect of uvHIV was not counteracted by a substantial reduction in the number of monocytes or by indomethacin. Moreover, IL-1 production by monocytes was not affected upon virus incubation. On the other hand, the proliferative response of both CD4+ and CD8+ T-cell clones was inhibited by uvHIV, suggesting that T cells represent the actual target for the inhibitory effect. Although a sizeable decrease in IL-2 production was observed following uvHIV incubation, exogenous IL-2 was not capable of reversing the virus-induced suppression of the proliferation. The possibility that the immunosuppressive activity of noninfectious HIV contributes to the T-cell defect in infected patients by mechanisms other than the cytopathic effect on CD4+ T lymphocytes is discussed.

  4. Recombinant Salmonella typhimurium strains that invade nonphagocytic cells are resistant to recognition by antigen-specific cytotoxic T lymphocytes.

    PubMed Central

    Gao, X M; Tite, J P; Lipscombe, M; Rowland-Jones, S; Ferguson, D J; McMichael, A J

    1992-01-01

    To address the question of whether Salmonella-infected nonphagocytic cells could serve as target cells for recognition by antigen-specific, major histocompatibility complex class I-restricted cytotoxic T lymphocytes (CTL), four recombinant Salmonella typhimurium constructs that expressed full-length, or fragments of, influenza A virus nucleoprotein (NP) were made. The bacteria were shown to infect Chinese hamster ovary (CHO) cells. Appropriate major histocompatibility complex restriction molecules, HLA-B27 and H-2 Db, were transfected into CHO cells, which were then infected with recombinant S. typhimurium and used as targets for NP-specific CTL. The cells in which NP was expressed by intracellularly replicating bacteria were not lysed by NP-specific CTL, although they were killed when appropriate influenza A virus or peptides were used. Thus, S.typhimurium bacteria within nonphagocytic cells were resistant to CTL recognition. In contrast to these results, mice infected with recombinant S.typhimurium that expressed fragments of NP in the periplasm were primed for NP-specific CTL responses. The results indicate that CTL responses specific to Salmonella antigens can be generated, but the bacteria may be safe from the CTL attack once they have entered the nonphagocytic cells. Images PMID:1500187

  5. A Chemokine Expressed in Lymphoid High Endothelial Venules Promotes the Adhesion and Chemotaxis of Naive T Lymphocytes

    NASA Astrophysics Data System (ADS)

    Gunn, Michael D.; Tangemann, Kirsten; Tam, Carmen; Cyster, Jason G.; Rosen, Steven D.; Williams, Lewis T.

    1998-01-01

    Preferential homing of naive lymphocytes to secondary lymphoid organs is thought to involve the action of chemokines, yet no chemokine has been shown to have either the expression pattern or the activities required to mediate this process. Here we show that a chemokine represented in the EST database, secondary lymphoid-tissue chemokine (SLC), is expressed in the high endothelial venules of lymph nodes and Peyer's patches, in the T cell areas of spleen, lymph nodes, and Peyer's patches, and in the lymphatic endothelium of multiple organs. SLC is a highly efficacious chemoattractant for lymphocytes with preferential activity toward naive T cells. Moreover, SLC induces firm adhesion of naive T lymphocytes via β 2 integrin binding to the counter receptor, intercellular adhesion molecule-1, a necessary step for lymphocyte recruitment. SLC is the first chemokine demonstrated to have the characteristics required to mediate homing of lymphocytes to secondary lymphoid organs. In addition, the expression of SLC in lymphatic endothelium suggests that the migration of lymphocytes from tissues into efferent lymphatics may be an active process mediated by this molecule.

  6. Multicolor flow cytometry analysis of the proliferations of T-lymphocyte subsets in vitro by EdU incorporation.

    PubMed

    Sun, Yanli; Sun, Yu; Lin, Guigao; Zhang, Rui; Zhang, Kuo; Xie, Jiehong; Wang, Lunan; Li, Jinming

    2012-10-01

    EdU (5-ethynyl-2'-deoxyuridine) incorporation has proved advantageous in the studies of cell kinetics, DNA synthesis, and cellular proliferation in vitro and in vivo compared to [(3) H]thymidine incorporation and BrdU (5-bromo-2'-deoxyuridine) incorporation. Here, we describe a method that combines EdU incorporation and immunostaining with flow cytometric analysis to detect the proliferations of T lymphocyte subsets in vitro and optimized the assay's conditions. We found that the number of EdU(+) cells were associated with EdU concentration, incubation time, and the volume of Click reaction solution, the best EdU concentration 10-50 μM, the optimal incubation time 8-12 h and the proper volume of Click volume 100 μl for labeling 1 × 10(6) lymphocytes. Fixation was better to be performed before permeabilization, not together with. Furthermore, the permeabilization detergent reagent, PBS with 0.05% saponin was better than Tris buffer saline (TBS) with 0.1% Triton X-100. In addition, sufficient wash with PBS with 0.05% saponin has no influence on the staining of EdU(+) cells. Also, the lymphocytes incorporating EdU could be stored at 4°C, -80°C, and in liquid nitrogen up to 21 days. The present study will aid in optimization of flow cytometry assay to detect the proliferations of T cell subsets by EdU incorporation and the labeling of cell surface antigens.

  7. Molecular pathways of adhesion in spontaneous rosetting of T-lymphocytes to the Hodgkin's cell line L428.

    PubMed

    Sanders, M E; Makgoba, M W; Sussman, E H; Luce, G E; Cossman, J; Shaw, S

    1988-01-01

    Spontaneous rosetting of T-lymphocytes to Reed-Sternberg cells has been observed both in vitro and in vivo but its molecular mechanism has not been defined. We have investigated such rosetting using the Hodgkin's cell line L428. L428 expresses high levels of LFA-3 and ICAM-1, both of which are ligands for T-cell adhesion. Monoclonal antibody inhibition of spontaneous rosetting indicated that it is not dependent on the T-cell receptor complex but is largely mediated by interaction of T-cell CD2 (T11/E-rosette receptor) with its ligand LFA-3 on L428 cells. Studies using an alternate assay of adhesion (conjugate formation) confirm the roles of CD2/LFA-3 and also implicate a second mode of binding via LFA-1 on T-cells to ICAM-1 on L428. These data explain the previously reported finding of T-cell rosetting with Reed-Sternberg cells as an exaggeration of normal antigen-independent T-cell adhesion.

  8. An Integrated Microfluidic Device for Monitoring Changes in Nitric Oxide Production in Single T-Lymphocyte (Jurkat) Cells

    PubMed Central

    Metto, Eve C.; Evans, Karsten; Barney, Patrick; Culbertson, Anne H.; Gunasekara, Dulan B.; Caruso, Giuseppe; Hulvey, Matthew K.; da Silva, Jose Alberto Fracassi; Lunte, Susan M.; Culbertson, Christopher T.

    2014-01-01

    A considerable amount of attention has been focused on the analysis of single cells in an effort to better understand cell heterogeneity in cancer and neurodegenerative diseases. Although microfluidic devices have several advantages for single cell analysis, few papers have actually demonstrated the ability of these devices to monitor chemical changes in perturbed biological systems. In this paper, a new microfluidic channel manifold is described that integrates cell transport, lysis, injection, electrophoretic separation, and fluorescence detection into a single device, making it possible to analyze individual cells at a rate of 10 cells/min in an automated fashion. The system was employed to measure nitric oxide (NO) production in single T-lymphocytes (Jurkat cells) using a fluorescent marker, 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM DA). The cells were also labeled with 6-carboxyfluorescein diacetate (6-CFDA) as an internal standard. The NO production by control cells was compared to that of cells stimulated using lipopolysaccharide (LPS), which is known to cause the expression of inducible nitric oxide synthase (iNOS) in immune-type cells. Statistical analysis of the resulting electropherograms from a population of cells indicated a twofold increase in NO production in the induced cells. These results compare nicely to a recently published bulk cell analysis of NO. PMID:24010877

  9. Polymer nanoparticles for cross-presentation of exogenous antigens and enhanced cytotoxic T-lymphocyte immune response

    PubMed Central

    Song, Chanyoung; Noh, Young-Woock; Lim, Yong Taik

    2016-01-01

    Effective induction of an antigen-specific cytotoxic T lymphocyte (CTL) immune response is one of the key goals of cancer immunotherapy. We report the design and fabrication of polyethylenimine (PEI)-coated polymer nanoparticles (NPs) as efficient antigen-delivery carriers that can induce antigen cross-presentation and a strong CTL response. After synthesis of poly(d,l-lactide-co-glycolide) (PLGA) NPs containing ovalbumin (OVA) by the double-emulsion solvent-evaporation method, cationic-charged PLGA NPs were generated by coating them with PEI. In a methyl tetrazolium salt assay, no discernible cytotoxic effect of PEI-coated PLGA (OVA) NPs was observed. The capacity and mechanism of PEI-coated PLGA (OVA) NPs for antigen delivery and cross-presentation on dendritic cells (DCs) were determined by fluorescence microscopy and flow cytometry. PEI-coated PLGA (OVA) NPs were internalized efficiently via phagocytosis or macropinocytosis in DCs and induced efficient cross-presentation of the antigen on MHC class I molecules via both endosome escape and a lysosomal processing mechanism. The DCs treated with PEI-coated PLGA (OVA) NPs induced a release of IL-2 cytokine from OVA-specific CD8-OVA1.3 T cells more efficiently than DCs treated with PLGA (OVA) NPs. Therefore, the PEI-coated PLGA (OVA) NPs can induce antigen cross-presentation and are expected to be used for induction of a strong CTL immune response and for efficient anticancer immunotherapy. PMID:27540289

  10. Murine T lymphocytes and T-lymphoma cells produce chondroitin sulphate and heparan sulphate proteoglycans and free heparan sulphate glycosaminoglycan.

    PubMed Central

    Wilson, A P; Rider, C C

    1991-01-01

    Normal murine splenic T lymphocytes and T-lymphoma cells were incubated with [35S]sulphate in low-sulphate medium for 4 hr. Gel filtration and SDS-PAGE revealed that the radiolabelled macromolecules secreted by these cells were almost exclusively chondroitin sulphate and heparan sulphate proteoglycans of relatively low molecular weight (MW), 100,000-200,000. Triton X-100 extracts of the cells contained similar proteoglycans. Under the conditions employed the incorporation of radiolabel by cells grown in vivo was equally distributed between cell-retained and secreted fractions, whereas cells grown in vitro retained some 75% of incorporated label. In general heparan sulphate predominated over chondroitin sulphate in both secreted and cell-retained fractions. Cell extracts also contained a minor proportion of free glycosaminoglycan, which is almost exclusively heparan sulphate. These chains, like those incorporated into the proteoglycan, were around 12,000 MW. The T-lymphoma cells RDM-4, whether grown in vitro or in vivo, also incorporated a substantial proportion of [35S]sulphate into a single, cell-retained protein, 100,000 MW. No such radiolabelled protein was detectable in T cells. Images Figure 3 Figure 4 Figure 5 PMID:1900056

  11. Human T lymphocytes express N-methyl-D-aspartate receptors functionally active in controlling T cell activation

    SciTech Connect

    Miglio, Gianluca; Varsaldi, Federica; Lombardi, Grazia . E-mail: lombardi@pharm.unipmn.it

    2005-12-30

    The aim of this study was to investigate the expression and the functional role of N-methyl-D-aspartate (NMDA) receptors in human T cells. RT-PCR analysis showed that human resting peripheral blood lymphocytes (PBL) and Jurkat T cells express genes encoding for both NR1 and NR2B subunits: phytohemagglutinin (PHA)-activated PBL also expresses both these genes and the NR2A and NR2D genes. Cytofluorimetric analysis showed that NR1 expression increases as a consequence of PHA (10 {mu}g/ml) treatment. D-(-)-2-Amino-5-phosphonopentanoic acid (D-AP5), and (+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine [(+)-MK 801], competitive and non-competitive NMDA receptor antagonists, respectively, inhibited PHA-induced T cell proliferation, whereas they did not affect IL-2 (10 U/ml)-induced proliferation of PHA blasts. These effects were due to the prevention of T cell activation (inhibition of cell aggregate formation and CD25 expression), but not to cell cycle arrest or death. These results demonstrate that human T lymphocytes express NMDA receptors, which are functionally active in controlling cell activation.

  12. Dendritic cells transduced with Rsf-1/HBXAP gene generate specific cytotoxic T lymphocytes against ovarian cancer in vitro

    SciTech Connect

    Sun, Li; Kong, Beihua; Sheng, Xiugui; Sheu, Jim Jinn-Chyuan; Shih, Ie-Ming

    2010-04-09

    Recently, some studies have indicated that Rsf-1/HBXAP plays a role in chromatin remodeling and transcriptional regulation that may contribute to tumorigenesis in ovarian cancer. The present study demonstrates that using dendritic cells (DCs) from human cord blood CD34{sup +} cells transduced with Rsf-1/HBXAP DNA plasmids by nucleofection generate specific cytotoxic T lymphocytes (CTL) against ovarian cancer in vitro. After transfection, DCs were analyzed for Rsf-1/HBXAP mRNA expression by RT-PCR and protein expression by Western blot. Then the DC phenotypes, T-cell stimulatory capacity, endocytic activity and migration capacity were explored by flow cytometry analysis, allogeneic mixed lymphocyte reaction, endocytosis and transwell chemotaxis assay, respectively. After transfection, Rsf-1/HBXAP expression was detected at mRNA and protein levels. Allogeneic T-cell proliferation induced by transfected DCs was obviously higher than non-transfected DCs, but the endocytosis capacity and migratory ability were not different. Rsf-1/HBXAP gene-transduced DCs could induce antigen-specific CTL and generate a very potent cytotoxicity to OVCAR3 cells. These data suggest that Rsf-1/HBXAP gene-transduced DCs may be a potential adjuvant immunotherapy for ovarian cancer in clinical applications.

  13. Pharmacological Inhibition of Host Heme Oxygenase-1 Suppresses Mycobacterium tuberculosis Infection In Vivo by a Mechanism Dependent on T Lymphocytes.

    PubMed

    Costa, Diego L; Namasivayam, Sivaranjani; Amaral, Eduardo P; Arora, Kriti; Chao, Alex; Mittereder, Lara R; Maiga, Mamoudou; Boshoff, Helena I; Barry, Clifton E; Goulding, Celia W; Andrade, Bruno B; Sher, Alan

    2016-10-25

    Heme oxygenase-1 (HO-1) is a stress response antioxidant enzyme which catalyzes the degradation of heme released during inflammation. HO-1 expression is upregulated in both experimental and human Mycobacterium tuberculosis infection, and in patients it is a biomarker of active disease. Whether the enzyme plays a protective versus pathogenic role in tuberculosis has been the subject of debate. To address this controversy, we administered tin protoporphyrin IX (SnPPIX), a well-characterized HO-1 enzymatic inhibitor, to mice during acute M. tuberculosis infection. These SnPPIX-treated animals displayed a substantial reduction in pulmonary bacterial loads comparable to that achieved following conventional antibiotic therapy. Moreover, when administered adjunctively with antimycobacterial drugs, the HO-1 inhibitor markedly enhanced and accelerated pathogen clearance. Interestingly, both the pulmonary induction of HO-1 expression and the efficacy of SnPPIX treatment in reducing bacterial burden were dependent on the presence of host T lymphocytes. Although M. tuberculosis expresses its own heme-degrading enzyme, SnPPIX failed to inhibit its enzymatic activity or significantly restrict bacterial growth in liquid culture. Together, the above findings reveal mammalian HO-1 as a potential target for host-directed monotherapy and adjunctive therapy of tuberculosis and identify the immune response as a critical regulator of this function.

  14. Functional Alteration of Natural Killer Cells and Cytotoxic T Lymphocytes upon Asbestos Exposure and in Malignant Mesothelioma Patients

    PubMed Central

    Nishimura, Yasumitsu; Kumagai-Takei, Naoko; Matsuzaki, Hidenori; Lee, Suni; Maeda, Megumi; Kishimoto, Takumi; Fukuoka, Kazuya; Nakano, Takashi; Otsuki, Takemi

    2015-01-01

    Malignant mesothelioma is caused by exposure to asbestos, which is known to have carcinogenic effects. However, the development of mesothelioma takes a long period and results from a low or intermediate dose of exposure. These findings have motivated us to investigate the immunological effects of asbestos exposure and analyze immune functions of patients with mesothelioma and pleural plaque, a sign of exposure to asbestos. Here, we review our knowledge concerning natural killer (NK) cells and cytotoxic T lymphocytes (CTL). NK cells showed impaired cytotoxicity with altered expression of activating receptors upon exposure to asbestos, while induction of granzyme+ cells in CD8+ lymphocytes was suppressed by asbestos exposure. It is interesting that a decrease in NKp46, a representative activating receptor, is common between NK cells in PBMC culture with asbestos and those of mesothelioma patients. Moreover, it was observed that CD8+ lymphocytes may be stimulated by some kind of “nonself” cells in plaque-positive individuals and in mesothelioma patients, whereas CTL in mesothelioma is impaired by poststimulation maintenance of cytotoxicity. These findings suggest that analysis of immunological parameters might contribute to the evaluation of health conditions of asbestos-exposed individuals and to a greater understanding of the pathology of malignant mesothelioma. PMID:26161391

  15. Treatment of solid organ transplant recipients with autologous Epstein Barr virus–specific cytotoxic T lymphocytes (CTLs)

    PubMed Central

    Savoldo, Barbara; Goss, John A.; Hammer, Markus M.; Zhang, Lan; Lopez, Teresita; Gee, Adrian P.; Lin, Yu-Feng; Quiros-Tejeira, Ruben E.; Reinke, Petra; Schubert, Stephan; Gottschalk, Stephen; Finegold, Milton J.; Brenner, Malcolm K.; Rooney, Cliona M.; Heslop, Helen E.

    2006-01-01

    We have investigated the in vivo safety, efficacy, and persistence of autologous Epstein Barr virus (EBV)–specific cytotoxic T lymphocytes (CTLs) for the treatment of solid organ transplant (SOT) recipients at high risk for EBV-associated posttransplantation lymphoproliferative disease (PTLD). EBV-CTLs generated from 35 patients expanded with normal kinetics contained both CD8 and CD4 lymphocytes and produced significant specific killing of autologous EBV-transformed B lymphoblastoid cell lines (LCLs). Twelve SOT recipients at high risk for PTLD, or with active disease, received autologous CTL infusions without toxicity. Real-time polymerase chain reaction (PCR) monitoring of EBV-DNA showed a transient increase in plasma EBV-DNA suggestive of lysis of EBV-infected cells, although there was no consistent decrease in virus load in peripheral-blood mononuclear cells. Interferon-γ enzyme-linked immunospot (ELISPOT) assay and tetramer analysis showed an increase in the frequency of EBV-responsive T cells, which returned to preinfusion levels after 2 to 6 months. None of the treated patients developed PTLD. One patient with liver PTLD showed a complete response, and one with ocular disease has had a partial response stable for over