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Sample records for helper integration site-1

  1. Helper Hats

    ERIC Educational Resources Information Center

    Ashbrook, Peggy

    2010-01-01

    Special clothing is worn by "community helpers" such as police officers, nurses, firefighters, cafeteria workers, dentists, and waste management workers as they do their jobs. The special clothing allows workers to be safe. Therefore, exploring how hats help community workers do their jobs can be a way to introduce the idea of how the shape or…

  2. Proviral integration site for Moloney murine leukemia virus (PIM) kinases promote human T helper 1 cell differentiation.

    PubMed

    Tahvanainen, Johanna; Kyläniemi, Minna K; Kanduri, Kartiek; Gupta, Bhawna; Lähteenmäki, Hanna; Kallonen, Teemu; Rajavuori, Anna; Rasool, Omid; Koskinen, Päivi J; Rao, Kanury V S; Lähdesmäki, Harri; Lahesmaa, Riitta

    2013-02-01

    The differentiation of human primary T helper 1 (Th1) cells from naïve precursor cells is regulated by a complex, interrelated signaling network. The identification of factors regulating the early steps of Th1 cell polarization can provide important insight in the development of therapeutics for many inflammatory and autoimmune diseases. The serine/threonine-specific proviral integration site for Moloney murine leukemia virus (PIM) kinases PIM1 and PIM2 have been implicated in the cytokine-dependent proliferation and survival of lymphocytes. We have established that the third member of this family, PIM3, is also expressed in human primary Th cells and identified a new function for the entire PIM kinase family in T lymphocytes. Although PIM kinases are expressed more in Th1 than Th2 cells, we demonstrate here that these kinases positively influence Th1 cell differentiation. Our RNA interference results from human primary Th cells also suggest that PIM kinases promote the production of IFNγ, the hallmark cytokine produced by Th1 cells. Consistent with this, they also seem to be important for the up-regulation of the critical Th1-driving factor, T box expressed in T cells (T-BET), and the IL-12/STAT4 signaling pathway during the early Th1 differentiation process. In summary, we have identified PIM kinases as new regulators of human primary Th1 cell differentiation, thus providing new insights into the mechanisms controlling the selective development of human Th cell subsets. PMID:23209281

  3. Using Multicultural Literature To Enhance Elementary Peer Helper Training.

    ERIC Educational Resources Information Center

    Holcomb-McCoy, Cheryl

    2003-01-01

    Describes how to integrate multicultural literature into the training of elementary peer helpers in today's diverse schools, thus enhancing peer helpers' cultural sensitivity. The article focuses on: integrating multicultural literature into training, the multicultural literature training format, and implications for selecting literature. It also…

  4. B-cell-specific Moloney murine leukemia virus integration site 1: potential stratification factor and therapeutic target for epithelial ovarian cancer.

    PubMed

    Zhao, Qianying; Gui, Ting; Qian, Qiuhong; Li, Lei; Shen, Keng

    2016-01-01

    Epithelial ovarian cancer, a vexing challenge for clinical management, still lacks biomarkers for early diagnosis, precise stratification, and prognostic evaluation of patients. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI1), a member of the polycomb group of proteins, engages in diverse cellular processes, including proliferation, differentiation, senescence, and stem cell renewal. In addition, BMI1, as a cancer stem-cell marker, participates in tumorigenesis through various pathways. Rewardingly, recent studies have also revealed a relationship between BMI1 expression and the clinical grade/stage, therapy response, and survival outcome in a majority of human malignancies, including epithelial ovarian cancer. Therefore, BMI1 might serve as a potential stratification factor and treatment target for epithelial ovarian cancer, pending evidence from further investigations. PMID:27578986

  5. B-cell-specific Moloney murine leukemia virus integration site 1: potential stratification factor and therapeutic target for epithelial ovarian cancer

    PubMed Central

    Zhao, Qianying; Gui, Ting; Qian, Qiuhong; Li, Lei; Shen, Keng

    2016-01-01

    Epithelial ovarian cancer, a vexing challenge for clinical management, still lacks biomarkers for early diagnosis, precise stratification, and prognostic evaluation of patients. B-cell-specific Moloney murine leukemia virus integration site 1 (BMI1), a member of the polycomb group of proteins, engages in diverse cellular processes, including proliferation, differentiation, senescence, and stem cell renewal. In addition, BMI1, as a cancer stem-cell marker, participates in tumorigenesis through various pathways. Rewardingly, recent studies have also revealed a relationship between BMI1 expression and the clinical grade/stage, therapy response, and survival outcome in a majority of human malignancies, including epithelial ovarian cancer. Therefore, BMI1 might serve as a potential stratification factor and treatment target for epithelial ovarian cancer, pending evidence from further investigations. PMID:27578986

  6. Helper-Dependent Adenoviral Vectors

    PubMed Central

    Rosewell, Amanda; Vetrini, Francesco; Ng, Philip

    2012-01-01

    Helper-dependent adenoviral vectors are devoid of all viral coding sequences, possess a large cloning capacity, and can efficiently transduce a wide variety of cell types from various species independent of the cell cycle to mediate long-term transgene expression without chronic toxicity. These non-integrating vectors hold tremendous potential for a variety of gene transfer and gene therapy applications. Here, we review the production technologies, applications, obstacles to clinical translation and their potential resolutions, and the future challenges and unanswered questions regarding this promising gene transfer technology. PMID:24533227

  7. Preclinical activity of the novel B-cell-specific Moloney murine leukemia virus integration site 1 inhibitor PTC-209 in acute myeloid leukemia: Implications for leukemia therapy.

    PubMed

    Nishida, Yuki; Maeda, Aya; Chachad, Dhruv; Ishizawa, Jo; Qiu, Yi Hua; Kornblau, Steven M; Kimura, Shinya; Andreeff, Michael; Kojima, Kensuke

    2015-12-01

    Curing patients with acute myeloid leukemia (AML) remains a therapeutic challenge. The polycomb complex protein B-cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) is required for the self-renewal and maintenance of leukemia stem cells. We investigated the prognostic significance of BMI-1 in AML and the effects of a novel small molecule selective inhibitor of BMI-1, PTC-209. BMI-1 protein expression was determined in 511 newly diagnosed AML patients together with 207 other proteins using reverse-phase protein array technology. Patients with unfavorable cytogenetics according to Southwest Oncology Group criteria had higher levels of BMI-1 compared to those with favorable (P = 0.0006) or intermediate cytogenetics (P = 0.0061), and patients with higher levels of BMI-1 had worse overall survival (55.3 weeks vs. 42.8 weeks, P = 0.046). Treatment with PTC-209 reduced protein level of BMI-1 and its downstream target mono-ubiquitinated histone H2A and triggered several molecular events consistent with the induction of apoptosis, this is, loss of mitochondrial membrane potential, caspase-3 cleavage, BAX activation, and phosphatidylserine externalization. PTC-209 induced apoptosis in patient-derived CD34(+)CD38(low/-) AML cells and, less prominently, in CD34(-) differentiated AML cells. BMI-1 reduction by PTC-209 directly correlated with apoptosis induction in CD34(+) primary AML cells (r = 0.71, P = 0.022). However, basal BMI-1 expression was not a determinant of AML sensitivity. BMI-1 inhibition, which targets a primitive AML cell population, might offer a novel therapeutic strategy for AML. PMID:26450753

  8. Integrative effect of defective interfering RNA accumulation and helper virus attenuation is responsible for the persistent infection of Japanese encephalitis virus in BHK-21 cells.

    PubMed

    Park, Soo Young; Choi, Eunmi; Jeong, Yong Seok

    2013-11-01

    Persistence of RNA viruses is often, but not always, associated with the production of defective interfering (DI) particles. To investigate possible roles of DI particles and helper viruses in RNA virus persistence, persistent infection with Japanese encephalitis virus (JEV) was established in baby hamster kidney (BHK-21) cells. At the 6th and 7th serial undiluted passages of JEV on BHK-21 cells, viral persistence was established spontaneously with DI RNA generation. Seven cell clones exhibiting persistent infection were obtained from the initial BHK-21 cell batches exhibiting JEV persistence, and maintained for over 400 days. Most cell clones produced infectious particles (10(1) -10(5)  PFU/ml) continuously, expressed viral proteins, and resisted homologous superinfection. Two helper viruses, chvBS6-3 and chvBS7-1, were isolated from two of the seven cell clones, and characterized to investigate their roles in JEV persistence. While chvBS6-3 was restored to its full cytopathicity in the absence of DI RNA, chvBS7-1 exhibited almost no cytopathicity, regardless of DI RNA co-replication. Attenuation of chvBS7-1 did not appear to be due to inadequate adsorption or genome replication, but due to inefficient egress of the assembled progeny virions, suggesting altered helper virus emergence during JEV persistence in BHK-21 cells. These observations suggest that at least two mechanisms are involved in JEV persistence; a DI RNA-dependent mechanism, where DI RNA co-replication nullifies the helper virus's cytopathicity, or a DI RNA-independent mechanism, where the helper virus is self-attenuated. This study provides a useful in vitro tool for understanding the mechanisms underlying RNA virus persistent infections.

  9. 30 CFR 57.7009 - Drill helpers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill helpers. 57.7009 Section 57.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7009 Drill helpers. If a drill helper assists the drill operator during...

  10. 30 CFR 57.7009 - Drill helpers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill helpers. 57.7009 Section 57.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7009 Drill helpers. If a drill helper assists the drill operator during...

  11. 30 CFR 56.7009 - Drill helpers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drill helpers. 56.7009 Section 56.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7009 Drill helpers. If a drill helper assists the drill operator during movement of a...

  12. 30 CFR 56.7009 - Drill helpers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill helpers. 56.7009 Section 56.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7009 Drill helpers. If a drill helper assists the drill operator during movement of a...

  13. 30 CFR 57.7009 - Drill helpers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill helpers. 57.7009 Section 57.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7009 Drill helpers. If a drill helper assists the drill operator during...

  14. 30 CFR 56.7009 - Drill helpers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Drill helpers. 56.7009 Section 56.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7009 Drill helpers. If a drill helper assists the drill operator during movement of a...

  15. 30 CFR 57.7009 - Drill helpers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill helpers. 57.7009 Section 57.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7009 Drill helpers. If a drill helper assists the drill operator during...

  16. 30 CFR 56.7009 - Drill helpers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Drill helpers. 56.7009 Section 56.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7009 Drill helpers. If a drill helper assists the drill operator during movement of a...

  17. 30 CFR 57.7009 - Drill helpers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Drill helpers. 57.7009 Section 57.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface Only § 57.7009 Drill helpers. If a drill helper assists the drill operator during...

  18. 30 CFR 56.7009 - Drill helpers.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Drill helpers. 56.7009 Section 56.7009 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7009 Drill helpers. If a drill helper assists the drill operator during movement of a...

  19. Peer Helpers in Hungary: A Qualitative Analysis

    ERIC Educational Resources Information Center

    Racz, Jozsef; Lacko, Zsuzsa

    2008-01-01

    Hungary is a country in transition that has no real tradition of peer helping. A qualitative study was carried out involving 13 peer helpers of two kinds (a) age-based peers, and (b) way-of-life-based peers (fellow helpers). The motivations for and the processes of becoming a peer helper were analyzed. Results showed the largest difference being…

  20. Expression of B cell-specific Moloney murine leukemia virus integration site 1 in vulvar squamous cell carcinoma and its effect on the biological behavior of A-431 cells

    PubMed Central

    BAI, XUELI; OUYANG, LING; LI, BO; ZHOU, YANG; WEN, XIN

    2015-01-01

    The aim of the present study was to investigate the expression of B cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) in vulvar squamous cell carcinoma (VSCC) and vulvar intraepithelial neoplasia (VIN). Furthermore, the present study investigated the effects of BMI-1 expression on the biological behavior of A-431 human epidermoid carcinoma cells. BMI-1 expression in human VSCC and VIN tissues was detected using immunohistochemistry. Subsequently, BMI-1 expression was silenced in A-431 cells using small interfering RNA (siRNA), and BMI-1 expression was detected using reverse transcription-quantitative polymerase chain reaction and western blotting. The effects of BMI-1 silencing on cell proliferation, apoptosis and invasive ability were determined using an MTT assay, Annexin V-fluorescein isothiocyanate/propidium iodide double-labeling experiment and Transwell assay, respectively. The expression rate of BMI-1 in normal vulvar, VIN and VSCC tissues was 0.0, 25.0 and 68.0% respectively, demonstrating an increasing trend in the severity of the disease. BMI-1 overexpression was found not to correlate with age, pathological stage, lymph node metastasis or degree of differentiation (P>0.05). BMI-1 siRNA transfection effectively inhibited BMI-1 messenger RNA and protein expression in A-431 cells. The mean rate of apoptosis promotion and proliferation inhibition in the most effectively silenced group were 20.19 and 46.82%, respectively, which was significantly higher than that of the cells in the blank and control siRNA groups (P<0.05). The number of invading cells was decreased in the most effectively silenced group compared with that of the blank and control siRNA groups. Abnormal expression of BMI-1 was also detected in VIN and VSCC tissues, and targeting of BMI-1 with siRNA was able to successfully silence BMI-1 expression in A-431 cells. Silencing of BMI-1 promoted apoptosis and inhibited the invasive abilities of A-431 cells in vitro. PMID

  1. Doing Good: Counseling and the "Helper's High."

    ERIC Educational Resources Information Center

    Kottler, Jeffrey A.

    1994-01-01

    In support of a previous article entitled "Counseling Endorphins" (CG 546 741), the author addresses the nature of altruism and the "helper's high" as they affect what counselors do with their clients and their lives. (JPS)

  2. Pharmacoimmunodynamics of Methylprednisolone: Trafficking of Helper T Lymphocytes

    PubMed Central

    Fisher, Lynn E.; Ludwig, Elizabeth A.; Jusko, William J.

    2014-01-01

    A two-compartment closed model was used to characterize the cell trafficking behavior of helper T cells in response to various single doses of methylprednisolone. Steroids are assumed to inhibit the circadian-determined cell return from extravascular sites to blood in a classic inhibitory pattern reflected by an IC50. The rate of cell efflux from tissues is modeled with a cosine function having a period of 24 hr and a maximum at about 1 AM. Nonlinear least-squares regression employing differential equations was used to analyze helper T-cell data from three human studies from our laboratory. The IC50 value of methylprednisolone of 12–19 ng/ml approximates receptor KD values. Simulations were performed to demonstrate the log-linear role of steroid dose or AUC on the integral of effect of helper T cells over a wide range of methylprednisolone doses. This pharmacodynamic model allows flexibility for characterizing any type of steroid dosing regimen and is relevent in describing complex response data for corticosteroid immunosuppressive effects PMID:1479558

  3. Cost minimization by helpers in cooperative vertebrates.

    PubMed

    Russell, A F; Sharpe, L L; Brotherton, P N M; Clutton-Brock, T H

    2003-03-18

    When parents invest heavily in reproduction they commonly suffer significant energetic costs. Parents reduce the long-term fitness implications of these costs through increased foraging and reduced reproductive investment in the future. Similar behavioral modifications might be expected among helpers in societies of cooperative vertebrates, in which helping is associated with energetic costs. By using multivariate analyses and experiments, we show that in cooperative meerkats, Suricata suricatta, helping is associated with substantial short-term growth costs but limited long-term fitness costs. This association forms because individual contributions to cooperation are initially condition dependent, and, because when helpers invest heavily in cooperation, they increase their foraging rate during the subsequent nonbreeding period and reduce their level of cooperative investment in the subsequent reproductive period. These results provide a unique demonstration that despite significant short-term costs, helpers, like breeders, are able to reduce the fitness consequences of these costs through behavioral modifications.

  4. Cost minimization by helpers in cooperative vertebrates.

    PubMed

    Russell, A F; Sharpe, L L; Brotherton, P N M; Clutton-Brock, T H

    2003-03-18

    When parents invest heavily in reproduction they commonly suffer significant energetic costs. Parents reduce the long-term fitness implications of these costs through increased foraging and reduced reproductive investment in the future. Similar behavioral modifications might be expected among helpers in societies of cooperative vertebrates, in which helping is associated with energetic costs. By using multivariate analyses and experiments, we show that in cooperative meerkats, Suricata suricatta, helping is associated with substantial short-term growth costs but limited long-term fitness costs. This association forms because individual contributions to cooperation are initially condition dependent, and, because when helpers invest heavily in cooperation, they increase their foraging rate during the subsequent nonbreeding period and reduce their level of cooperative investment in the subsequent reproductive period. These results provide a unique demonstration that despite significant short-term costs, helpers, like breeders, are able to reduce the fitness consequences of these costs through behavioral modifications. PMID:12629209

  5. Using Peer Helpers for Tuberculosis Prevention.

    ERIC Educational Resources Information Center

    McCue, Maureen; Afifi, Larry Anna

    1996-01-01

    Describes a peer helper program initiated by the University of Iowa Student Health Services to prevent active tuberculosis development among foreign national students. Before instituting the program, compliance with tuberculosis prevention efforts for those students was less than 5%. Since the peer program was instituted, compliance has risen to…

  6. Electrician's Helper. Coordinator's Guide. Individualized Study Guide.

    ERIC Educational Resources Information Center

    Stotts, Danny

    This guide is designed to assist teacher-coordinators supervising cooperative education programs for electrician's helpers in helping students complete a set of individualized, competency-based training activities dealing with electricity and electrical circuits and equipment. The first part of the manual includes a progress chart, a study guide…

  7. Conflict Resolution and Mediation for Peer Helpers.

    ERIC Educational Resources Information Center

    Sorenson, Don L.

    This book explores conflict resolution strategies and presents a systematic approach to mediation for peer helpers. The first part examines conflict resolution. Internal and external sources of conflict are considered. Irritations, inappropriate expectations, and unknown sources of external conflict are examined. A section on looking inside…

  8. Plumber's Helper. Coordinator's Guide. Individualized Study Guide.

    ERIC Educational Resources Information Center

    Traylor, Charles R.

    This individualized, competency-based study guide is designed to assist teacher-coordinators supervising cooperative education programs for plumber's helpers in providing students with general information for immediate reinforcement on the job and developing an understanding of the job prior to employment. A progress chart is provided to allow the…

  9. Beyond Helper Phage: Using "Helper Cells" to Select Peptide Affinity Ligands.

    PubMed

    Phipps, M Lisa; Lillo, Antoinetta M; Shou, Yulin; Schmidt, Emily N; Paavola, Chad D; Naranjo, Leslie; Bemdich, Sara; Swanson, Basil I; Bradbury, Andrew R M; Martinez, Jennifer S

    2016-01-01

    Peptides are important affinity ligands for microscopy, biosensing, and targeted delivery. However, because they can have low affinity for their targets, their selection from large naïve libraries can be challenging. When selecting peptidic ligands from display libraries, it is important to: 1) ensure efficient display; 2) maximize the ability to select high affinity ligands; and 3) minimize the effect of the display context on binding. The "helper cell" packaging system has been described as a tool to produce filamentous phage particles based on phagemid constructs with varying display levels, while remaining free of helper phage contamination. Here we report on the first use of this system for peptide display, including the systematic characterization and optimization of helper cells, their inefficient use in antibody display and their use in creating and selecting from a set of phage display peptide libraries. Our libraries were analyzed with unprecedented precision by standard or deep sequencing, and shown to be superior in quality than commercial gold standards. Using our helper cell libraries, we have obtained ligands recognizing Yersinia pestis surface antigen F1V and L-glutamine-binding periplasmic protein QBP. In the latter case, unlike any of the peptide library selections described so far, we used a combination of phage and yeast display to select intriguing peptide ligands. Based on the success of our selections we believe that peptide libraries obtained with helper cells are not only suitable, but preferable to traditional phage display libraries for selection of peptidic ligands. PMID:27626637

  10. Beyond Helper Phage: Using "Helper Cells" to Select Peptide Affinity Ligands

    PubMed Central

    Shou, Yulin; Schmidt, Emily N.; Paavola, Chad D.; Naranjo, Leslie; Bemdich, Sara; Swanson, Basil I.; Bradbury, Andrew R. M.; Martinez, Jennifer S.

    2016-01-01

    Peptides are important affinity ligands for microscopy, biosensing, and targeted delivery. However, because they can have low affinity for their targets, their selection from large naïve libraries can be challenging. When selecting peptidic ligands from display libraries, it is important to: 1) ensure efficient display; 2) maximize the ability to select high affinity ligands; and 3) minimize the effect of the display context on binding. The “helper cell” packaging system has been described as a tool to produce filamentous phage particles based on phagemid constructs with varying display levels, while remaining free of helper phage contamination. Here we report on the first use of this system for peptide display, including the systematic characterization and optimization of helper cells, their inefficient use in antibody display and their use in creating and selecting from a set of phage display peptide libraries. Our libraries were analyzed with unprecedented precision by standard or deep sequencing, and shown to be superior in quality than commercial gold standards. Using our helper cell libraries, we have obtained ligands recognizing Yersinia pestis surface antigen F1V and L-glutamine-binding periplasmic protein QBP. In the latter case, unlike any of the peptide library selections described so far, we used a combination of phage and yeast display to select intriguing peptide ligands. Based on the success of our selections we believe that peptide libraries obtained with helper cells are not only suitable, but preferable to traditional phage display libraries for selection of peptidic ligands. PMID:27626637

  11. Beyond Helper Phage: Using "Helper Cells" to Select Peptide Affinity Ligands.

    PubMed

    Phipps, M Lisa; Lillo, Antoinetta M; Shou, Yulin; Schmidt, Emily N; Paavola, Chad D; Naranjo, Leslie; Bemdich, Sara; Swanson, Basil I; Bradbury, Andrew R M; Martinez, Jennifer S

    2016-01-01

    Peptides are important affinity ligands for microscopy, biosensing, and targeted delivery. However, because they can have low affinity for their targets, their selection from large naïve libraries can be challenging. When selecting peptidic ligands from display libraries, it is important to: 1) ensure efficient display; 2) maximize the ability to select high affinity ligands; and 3) minimize the effect of the display context on binding. The "helper cell" packaging system has been described as a tool to produce filamentous phage particles based on phagemid constructs with varying display levels, while remaining free of helper phage contamination. Here we report on the first use of this system for peptide display, including the systematic characterization and optimization of helper cells, their inefficient use in antibody display and their use in creating and selecting from a set of phage display peptide libraries. Our libraries were analyzed with unprecedented precision by standard or deep sequencing, and shown to be superior in quality than commercial gold standards. Using our helper cell libraries, we have obtained ligands recognizing Yersinia pestis surface antigen F1V and L-glutamine-binding periplasmic protein QBP. In the latter case, unlike any of the peptide library selections described so far, we used a combination of phage and yeast display to select intriguing peptide ligands. Based on the success of our selections we believe that peptide libraries obtained with helper cells are not only suitable, but preferable to traditional phage display libraries for selection of peptidic ligands.

  12. General pathologist-helper: The new medical app about general pathology

    PubMed Central

    Fernández-Vega, Iván

    2015-01-01

    Introduction: Smartphone applications (apps) have become increasingly prevalent in medicine. Due to most pathologists, pathology trainees, technicians, and medical students use smartphones; apps can be a different way for general pathology education. “General pathologist-helper (GP-HELPER)” is a novel app developed as a reference tool in general pathology and especially for general pathologists, developed for Android and iOS platforms. Materials and Methods: “GP-HELPER,” was created using Mobincube website platform. This tool also integrates “FORUM GP-HELPER,” an external website created using Miarroba website (http://forum-gp-helper.mboards.com) and “COMMUNITY GP-HELPER” a multichannel chat created using Chatango website platform. Results: The application was released in July 2015, and it is been periodically updated since then. The app has permanent information (offline data) about different pathology protocols (TNM latest edition, protocols regarding management of tumors of unknown primary origin, and flowcharts for some of the most difficult tumors to diagnose) and a database with more than 5000 immunohistochemistry results from different tumors. Online data have links to more than 1100 reference pathology video lectures, 250 antibodies information, more than 70 pathology association websites, 46 pathology providers, and 78 outstanding pathology journal websites. Besides this information, the app has two interactive places such as “FORUM GP-HELPER” and “COMMUNITY GP-HELPER” that let users to stay in touch everywhere and every time. Expert consult section is also available. Conclusions: “GP-HELPER” pretends to integrate offline and online data about pathology with two interactive external places in order to represent a reference tool for general pathologists and associate members. PMID:26730351

  13. A job analysis of care helpers.

    PubMed

    Shin, Su Jin; Choi, Kyung-Sook; Jeong, Seungeun; Kim, Seulgee; Park, Hyeung-Keun; Seok, Jae Eun

    2012-01-01

    The aim of this study was to examine the roles of care helpers through job analysis. To do this, this study used the Developing A Curriculum Method (DACUM) to classify job content and a multi-dimensional study design was applied to identify roles and create a job description by looking into the appropriateness, significance, frequency, and difficulty of job content as identified through workshops and cross-sectional surveys conducted for appropriateness verification. A total of 418 care helpers working in nursing facilities and community senior service facilities across the country were surveyed. The collected data were analyzed using PASW 18.0 software. Six duties and 18 tasks were identified based on the job model. Most tasks were found to be "important task", scoring 4.0 points or above. Physical care duties, elimination care, position changing and movement assistance, feeding assistance, and safety care were identified as high frequency tasks. The most difficult tasks were emergency prevention, early detection, and speedy reporting. A summary of the job of care helpers is providing physical, emotional, housekeeping, and daily activity assistance to elderly patients with problems in independently undertaking daily activities due to physical or mental causes in long-term care facilities or at the client's home. The results of this study suggest a task-focused examination, optimizing the content of the current standard teaching materials authorized by the Ministry of Health and Welfare while supplementing some content which was identified as task elements but not included in the current teaching materials and fully reflecting the actual frequency and difficulty of tasks.

  14. Communication skills training for paraprofessional helpers.

    PubMed

    Avery, A W

    1978-12-01

    The purpose of the present study was to develop and evaluate a training program for paraprofessional helpers. Twenty dormitory counselor candidates were given 20 hours of communication training while 15 other candidates were given no training. The results indicated that the trained subjects demonstrated significantly higher levels of empathy than the untrained subjects and that they maintained their level of empathy after 6 months. Results are discussed in terms of the lasting effects of the training program and the advantages of being able to use trainers with only limited experience. PMID:736009

  15. Beyond helper phage: Using "helper cells" to select peptide affinity ligands

    DOE PAGES

    Phipps, Mary Lisa; Lillo, Antoinetta M.; Shou, Yulin; Schmidt, Emily N.; Paavola, Chad D.; Naranjo, Leslie A.; Bemdich, Sara; Swanson, Basil I.; Bradbury, Andrew R. M.; Martinez, Jennifer S.; et al

    2016-09-14

    Peptides are important affinity ligands for microscopy, biosensing, and targeted delivery. However, because they can have low affinity for their targets, their selection from large naïve libraries can be challenging. When selecting peptidic ligands from display libraries, it is important to: 1) ensure efficient display; 2) maximize the ability to select high affinity ligands; and 3) minimize the effect of the display context on binding. The “helper cell” packaging system has been described as a tool to produce filamentous phage particles based on phagemid constructs with varying display levels, while remaining free of helper phage contamination. Here we report onmore » the first use of this system for peptide display, including the systematic characterization and optimization of helper cells, their inefficient use in antibody display and their use in creating and selecting from a set of phage display peptide libraries. Our libraries were analyzed with unprecedented precision by standard or deep sequencing, and shown to be superior in quality than commercial gold standards. Using our helper cell libraries, we have obtained ligands recognizing Yersinia pestis surface antigen F1V and L-glutamine-binding periplasmic protein QBP. In the latter case, unlike any of the peptide library selections described so far, we used a combination of phage and yeast display to select intriguing peptide ligands. Here, based on the success of our selections we believe that peptide libraries obtained with helper cells are not only suitable, but preferable to traditional phage display libraries for selection of peptidic ligands.« less

  16. Welder's Helper. Coordinator's Guide. Individualized Study Guide. General Metal Trades.

    ERIC Educational Resources Information Center

    Dean, James W.

    This guide provides information to enable coordinators to direct learning activities for students using an individualized study guide on being a welder's helper. The study material is designed for students enrolled in cooperative part-time training and employed, or desiring to be employed, as welders' helpers. Contents include a sample progress…

  17. Crisis Intervention Strategies for School-Based Helpers. Second Edition.

    ERIC Educational Resources Information Center

    Fairchild, Thomas N., Ed.

    School-based helpers are helping professionals who work within educational settings and whose training and primary responsibility is to promote the mental health of students. Few resource materials provide these helpers with needed information and practical strategies--this text tries to meet that need. The 12 chapters here cover a wide range of…

  18. Managing Stress and Burnout among Helpers in Rural Areas.

    ERIC Educational Resources Information Center

    Reed, John C.

    Individuals who work in the helping professions (physicians, counselors, nurses, pastors, and social workers) often work with individuals in stressful crisis situations. In addition to working in high stress situations, helpers in rural areas also suffer from isolation from support networks and peers that are available to urban helpers. This…

  19. Introduction of temperature-sensitive helper and donor plasmids into Bac-to-Bac baculovirus expression systems.

    PubMed

    Huang, Zhihong; Li, Ao; Pan, Mengjia; Wu, Wenbi; Yuan, Meijin; Yang, Kai

    2015-10-01

    In the baculovirus shuttle vector (bacmid) system, a helper plasmid and a donor plasmid are employed to insert heterologous genes into a cloned baculovirus genome via Tn7 transposition in Escherichia coli. The helper and donor plasmids are usually cotransfected with constructed bacmids into insect cells, which will lead to integration of these plasmids into the viral genome, and hence to the production of defective virions. In this study, to facilitate the preparation of plasmid-free recombinant bacmids, we modified a set of helper and donor plasmids by replacing their replication origins with that of a temperature-sensitive (ts) plasmid, pSIM6. Using the resulting ts helper plasmid pMON7124(ts) and the ts donor plasmid pFB1(ts)-PH-GFP, a recombinant bacmid, bAcWT-PG(-), was constructed, and the transposition efficiency was found to be 33.1%. The plasmids were then removed by culturing at 37 °C. For bAcWT-PG(-), the infectious progeny virus titer and the protein expression level under the control of the polyhedrin promoter were similar to those of a bacmid constructed with unmodified helper and donor plasmids. These ts plasmids will be useful for obtaining plasmid-free bacmids for both heterologous protein production and fundamental studies of baculovirus biology.

  20. FOLLICULAR HELPER T CELLS: LINEAGE AND LOCATION

    PubMed Central

    Fazilleau, Nicolas; Mark, Linda; McHeyzer-Williams, Louise J.; McHeyzer-Williams, Michael G.

    2009-01-01

    Follicular helper T (TFH) cells are the class of effector TH cells that regulates the stepwise development of antigen-specific B cell immunity in vivo. Deployment of CXCR5+ TFH cells to B cell zones of lymphoid tissues and stable cognate interactions with B cells are central to the delivery of antigen-specific TFH function. Recent advances help to unravel distinctive elements of developmental programming for TFH cells and unique effector TFH functions focused on antigen-primed B cells. Understanding the regulatory functions of TFH cells in the germinal center and the subsequent regulation of memory B cell responses to antigen recall represent the frontiers of this research area with the potential to alter fundamentally the design of future vaccines. PMID:19303387

  1. Helpers increase the reproductive potential of offspring in cooperative meerkats.

    PubMed

    Russell, A F; Young, A J; Spong, G; Jordan, N R; Clutton-Brock, T H

    2007-02-22

    In both animal and human societies, individuals may forego personal reproduction and provide care to the offspring of others. Studies aimed at investigating the adaptive nature of such cooperative breeding systems in vertebrates typically calculate helper 'fitness' from relationships of helper numbers and offspring survival to independence. The aim of this study is to use observations and supplemental feeding experiments in cooperatively breeding meerkats, Suricata suricatta, to investigate whether helpers influence the long-term reproductive potential of offspring during adulthood. We show that helpers have a significant and positive influence on the probability that offspring gain direct reproductive success in their lifetimes. This effect arises because helpers both reduce the age at which offspring begin to reproduce as subordinates and increase the probability that they will compete successfully for alpha rank. Supplemental feeding experiments confirm the causality of these results. Our results suggest that one can neither discount the significance of helper effects when none is found nor necessarily estimate accurately the fitness benefit that helpers accrue, unless their effects on offspring are considered in the long term.

  2. Helpers increase the reproductive potential of offspring in cooperative meerkats.

    PubMed

    Russell, A F; Young, A J; Spong, G; Jordan, N R; Clutton-Brock, T H

    2007-02-22

    In both animal and human societies, individuals may forego personal reproduction and provide care to the offspring of others. Studies aimed at investigating the adaptive nature of such cooperative breeding systems in vertebrates typically calculate helper 'fitness' from relationships of helper numbers and offspring survival to independence. The aim of this study is to use observations and supplemental feeding experiments in cooperatively breeding meerkats, Suricata suricatta, to investigate whether helpers influence the long-term reproductive potential of offspring during adulthood. We show that helpers have a significant and positive influence on the probability that offspring gain direct reproductive success in their lifetimes. This effect arises because helpers both reduce the age at which offspring begin to reproduce as subordinates and increase the probability that they will compete successfully for alpha rank. Supplemental feeding experiments confirm the causality of these results. Our results suggest that one can neither discount the significance of helper effects when none is found nor necessarily estimate accurately the fitness benefit that helpers accrue, unless their effects on offspring are considered in the long term. PMID:17476771

  3. Effects of helpers on juvenile development and survival in meerkats.

    PubMed

    Clutton-Brock, T H; Russell, A F; Sharpe, L L; Brotherton, P N; McIlrath, G M; White, S; Cameron, E Z

    2001-09-28

    Although breeding success is known to increase with group size in several cooperative mammals, the mechanisms underlying these relationships are uncertain. We show that in wild groups of cooperative meerkats, Suricata suricatta, reductions in the ratio of helpers to pups depress the daily weight gain and growth of pups and the daily weight gain of helpers. Increases in the daily weight gain of pups are associated with heavier weights at independence and at 1 year of age, as well as with improved foraging success as juveniles and higher survival rates through the first year of life. These results suggest that the effects of helpers on the fitness of pups extend beyond weaning and that helpers may gain direct as well as indirect benefits by feeding pups.

  4. Effects of helpers on juvenile development and survival in meerkats.

    PubMed

    Clutton-Brock, T H; Russell, A F; Sharpe, L L; Brotherton, P N; McIlrath, G M; White, S; Cameron, E Z

    2001-09-28

    Although breeding success is known to increase with group size in several cooperative mammals, the mechanisms underlying these relationships are uncertain. We show that in wild groups of cooperative meerkats, Suricata suricatta, reductions in the ratio of helpers to pups depress the daily weight gain and growth of pups and the daily weight gain of helpers. Increases in the daily weight gain of pups are associated with heavier weights at independence and at 1 year of age, as well as with improved foraging success as juveniles and higher survival rates through the first year of life. These results suggest that the effects of helpers on the fitness of pups extend beyond weaning and that helpers may gain direct as well as indirect benefits by feeding pups. PMID:11577235

  5. Follicular Helper T Cells in Autoimmunity.

    PubMed

    Scherm, Martin G; Ott, Verena B; Daniel, Carolin

    2016-08-01

    The development of multiple disease-relevant autoantibodies is a hallmark of autoimmune diseases. In autoimmune type 1 diabetes (T1D), a variable time frame of autoimmunity precedes the clinically overt disease. The relevance of T follicular helper (TFH) cells for the immune system is increasingly recognized. Their pivotal contribution to antibody production by providing help to germinal center (GC) B cells facilitates the development of a long-lived humoral immunity. Their complex differentiation process, involving various stages and factors like B cell lymphoma 6 (Bcl6), is strictly controlled, as anomalous regulation of TFH cells is connected with immunopathologies. While the adverse effects of a TFH cell-related insufficient humoral immunity are obvious, the role of increased TFH frequencies in autoimmune diseases like T1D is currently highlighted. High levels of autoantigen trigger an excessive induction of TFH cells, consequently resulting in the production of autoantibodies. Therefore, TFH cells might provide promising approaches for novel therapeutic strategies. PMID:27324759

  6. Variation in helper effort among cooperatively breeding bird species is consistent with Hamilton's Rule

    PubMed Central

    Green, Jonathan P.; Freckleton, Robert P.; Hatchwell, Ben J.

    2016-01-01

    Investment by helpers in cooperative breeding systems is extremely variable among species, but this variation is currently unexplained. Inclusive fitness theory predicts that, all else being equal, cooperative investment should correlate positively with the relatedness of helpers to the recipients of their care. We test this prediction in a comparative analysis of helper investment in 36 cooperatively breeding bird species. We show that species-specific helper contributions to cooperative brood care increase as the mean relatedness between helpers and recipients increases. Helper contributions are also related to the sex ratio of helpers, but neither group size nor the proportion of nests with helpers influence helper effort. Our findings support the hypothesis that variation in helping behaviour among cooperatively breeding birds is consistent with Hamilton's rule, indicating a key role for kin selection in the evolution of cooperative investment in social birds. PMID:27554604

  7. Variation in helper effort among cooperatively breeding bird species is consistent with Hamilton's Rule.

    PubMed

    Green, Jonathan P; Freckleton, Robert P; Hatchwell, Ben J

    2016-01-01

    Investment by helpers in cooperative breeding systems is extremely variable among species, but this variation is currently unexplained. Inclusive fitness theory predicts that, all else being equal, cooperative investment should correlate positively with the relatedness of helpers to the recipients of their care. We test this prediction in a comparative analysis of helper investment in 36 cooperatively breeding bird species. We show that species-specific helper contributions to cooperative brood care increase as the mean relatedness between helpers and recipients increases. Helper contributions are also related to the sex ratio of helpers, but neither group size nor the proportion of nests with helpers influence helper effort. Our findings support the hypothesis that variation in helping behaviour among cooperatively breeding birds is consistent with Hamilton's rule, indicating a key role for kin selection in the evolution of cooperative investment in social birds. PMID:27554604

  8. Transcriptional and epigenetic networks that drive helper T cell identities

    PubMed Central

    Shih, Han-Yu; Sciumè, Giuseppe; Poholek, Amanda C; Vahedi, Golnaz; Hirahara, Kiyoshi; Villarino, Alejandro V; Bonelli, Michael; Bosselut, Remy; Kanno, Yuka; Muljo, Stefan A; O’Shea, John J.

    2014-01-01

    The discovery of the specification of CD4+ helper T cells to discrete effector “lineages” represented a watershed event in conceptualizing mechanisms of host defense and immunoregulation. However, our appreciation for the actual complexity of helper T cell subsets continues unabated. Just as the Sami language of Scandinavia has 1000 different words for reindeer, the range of fates available for a CD4+ T cell is numerous and may be underestimated. Added to the crowded scene for helper T cell subsets is the continuously growing family of innate lymphoid cells (ILCs), endowed with common effector responses and the previously defined “master regulators” for CD4+ helper T cell subsets are also shared by ILC subsets. Within the context of this extraordinary complexity are concomitant advances in the understanding of transcriptomes and epigenomes. So what do terms like “lineage commitment” and helper T cell “specification” mean in the early 21st century? How do we put all of this together in a coherent conceptual framework? It would be arrogant to assume that we have a sophisticated enough understanding to seriously answer these questions. Instead, we will review the current status of the flexibility of helper T cell responses in relation to their genetic regulatory networks and epigenetic landscapes. Recent data have provided major surprises as to what master regulators can or cannot do, how they interact with other transcription factors and impact global genome-wide changes and how all these factors come together to influence helper cell function. PMID:25123275

  9. Regluating factors in helper T-cell maturation.

    PubMed

    Zollinger, L; Potworowski, E F; Rabourdin, A; Prévost, C; Paquette, M

    1980-06-01

    The effect of soluble and insoluble thymic fractions (STF and ITF, respectively) on the antibody response to sheep red blood cells (SRBC) was tested at different times after injection in mice. In normal mice, a temporary increase in the number of plaque forming cells (PFCs) was observed after injecting either ITF and STF, this increase being more prolonged when both fractions were injected together. In thymectomized, lethally irradiated mice repopulated with syngeneic untreated bone marrow, full reconstitution of T helper function was achieved only if both ITF and SFT were injected, partial reconstitution being obtained when either of these fractions was administered alone. In thymectomized, lethally irradiated mice repopulated with T-depleted bone marrow, reconstitution of the T helper function was only achieved when both ITF and SFT were administered. These results show that ITF and STF together constitute all the essential elements of the thymic microenvironment necessary to support the entire differentiation process of prethymic precurosors into helper T cells.

  10. Characterization of a human antigen specific helper factor

    SciTech Connect

    Richardson, B.

    1986-03-01

    While antigen (Ag) specific helper factors have been characterized in mice, similar molecules have not been identified in humans. To characterize human antigen specific helper molecules, an IL-2 dependent tetanus toxoid (T.T.) reactive T cell line was fused with a 6-thioguanine resistant CEM line, and hybrids selected in medium containing hypoxanthine and azaserine. Hybrids were screened by culturing the cells with /sup 35/S-Met then reacting the supernatants with T.T. or hepatitis vaccine immobilized on nitrocellulose. One hybrid, TT6BA-O, was identified which secreted a Met-containing molecule which bound T.T. but not hepatitis vaccine. Supernatants from TT6BA-O, but not the parent CEM line, when added to autologous peripheral blood mononuclear cells (PBMC's) stimulated secretion of T.T. specific antibodies (Abs). Specificity controls demonstrated that TT6BA-O supernatant did not induce antibodies to diphtheria toxoid, hepatitis vaccine or pneumococcal polysaccharide, and total immunoglobulin (lg) synthesis was minimally increased. In contrast, pokeweed mitogen stimulated significant lg synthesis as well as Ab's to pneumococcal polysaccharide and T.T. TT6BA-O supernatant induced anti-T.T.Ab's in autologous PBMC's but not PBMC's from 3 unrelated donors, suggesting that the activity of the helper factor is restricted, possibly by the MHC. The molecular weight of the helper factor was estimated at 100,000-150,000 by Sephacryl S-300 chromatography. Finally, the helper factor could be demonstrated to bind and elute from sephorose-immobilized T.T. and anti-DR antisera, but not anti-lg antisera or the T40/25 monoclonal antibody, which binds a nonpolymorphic determinant on the human T cell receptor. These results demonstrate that human Ag specific helper factors exist, bind antigen and bear class II MHC determinants.

  11. Genome Sequence of the Mycorrhizal Helper Bacterium Pseudomonas fluorescens BBc6R8

    PubMed Central

    Gross, H.; Morin, E.; Karpinets, T.; Utturkar, S.; Mehnaz, S.; Martin, F.; Frey-Klett, P.; Labbé, J.

    2014-01-01

    We report the draft genome sequence of the mycorrhizal helper bacterium Pseudomonas fluorescens strain BBc6R8. This is the first genome of a mycorrhizal helper bacterium. The draft genome contains 6,952,353 bp and is predicted to encode 6,317 open reading frames. Comparative genomic analyses will help to identify helper traits. PMID:24407649

  12. 15. BRIDGE TENDER ALBERT REEVES OF MAURICETOWN AND HELPER WALLY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. BRIDGE TENDER ALBERT REEVES OF MAURICETOWN AND HELPER WALLY HALES HOLDING HUGE KEY ABOVE HOLE IN DECK OF CENTER SWING SPAN TO REVEAL KEY BASETHE KEY IS SET UPON A MALE FITTING USED TO OPEN THE SPAN - Maurice River Pratt Through-Truss Swing Bridge, Spanning Maurice River, Mauricetown, Cumberland County, NJ

  13. A fine romance: T follicular helper cells and B cells.

    PubMed

    King, Cecile

    2011-06-24

    T follicular helper (Tfh) cells help B cells to generate affinity-matured antibodies. Three papers in this issue of Immunity (Choi et al., 2011; Kerfoot et al., 2011; Kitano et al., 2011) provide information about the reciprocal relationship between B cells and Tfh cells.

  14. Communicating bad news: a model for emergency mental health helpers.

    PubMed

    Nardi, Thomas J; Keefe-Cooperman, Kathleen

    2006-01-01

    This article addresses the concerns of the messenger/helper who must convey tragic news to individuals and families. It offers a model to be used as a guide to ease the stress on both the deliverer and receiver of bad news. The model uses the mnemonic, PEWTER (Prepare, Evaluate, Warn, Tell, Emotional Response, Regroup), to represent the six components of the communication process.

  15. Family Caregiving or Caregiving Alone: Who Helps the Helper?

    ERIC Educational Resources Information Center

    Sims-Gould, Joanie; Martin-Matthews, Anne

    2007-01-01

    This study advances the understanding of family caregiving by examining the relationship between adult children caregivers and their helpers. Specifically, it focuses on examining "who helps whom" and extends analyses beyond the dyadic focus of caregiving in later life. The focus on helping and caregiving addresses the variety of contributions and…

  16. A fine romance: T follicular helper cells and B cells.

    PubMed

    King, Cecile

    2011-06-24

    T follicular helper (Tfh) cells help B cells to generate affinity-matured antibodies. Three papers in this issue of Immunity (Choi et al., 2011; Kerfoot et al., 2011; Kitano et al., 2011) provide information about the reciprocal relationship between B cells and Tfh cells. PMID:21703537

  17. Supervising Helpers Who Work with the Trauma of Sexual Abuse

    ERIC Educational Resources Information Center

    Etherington, Kim

    2009-01-01

    This paper contributes to the ongoing discussion in this journal about counsellors' experiences of vicarious traumatisation (Sexton, 1999; Dunkley & Whelan, 2006a, b). It builds on my previous paper (Etherington, 2000a) that focused on the role of supervision in moderating the potential impact on helpers, and on the helping relationship, of…

  18. The Difficulties of a Curriculum Helper in an Urban School.

    ERIC Educational Resources Information Center

    Smith, Michael S.

    This paper describes the experiences of a teacher and a curriculum helper in designing and implementing a fifth grade language arts curriculum at an inner city, magnet school in Indianapolis (Indiana). The report describes the work in three phases: (1) making explicit the problems with the previous language arts curriculum; (2) formulating a plan…

  19. 49 CFR 232.219 - Double heading and helper service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Double heading and helper service. 232.219 Section 232.219 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.219 Double...

  20. 49 CFR 232.219 - Double heading and helper service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Double heading and helper service. 232.219 Section 232.219 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.219 Double...

  1. 49 CFR 232.219 - Double heading and helper service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Double heading and helper service. 232.219 Section 232.219 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.219 Double...

  2. 49 CFR 232.219 - Double heading and helper service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Double heading and helper service. 232.219 Section 232.219 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.219 Double...

  3. 49 CFR 232.219 - Double heading and helper service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Double heading and helper service. 232.219 Section 232.219 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... TRAINS AND EQUIPMENT; END-OF-TRAIN DEVICES Inspection and Testing Requirements § 232.219 Double...

  4. The Art of Developing a Career: A Helper's Guide.

    ERIC Educational Resources Information Center

    Friel, Theodore W.; Carkhuff, Robert R.

    The guide is a compilation of the student's book and supplementary information in the form of "helper notes" placed next to the appropriate student material. Features of the book include previews and reviews, student activities, and summarizing cartoon illustrations helpful to nonreaders. Based on the phases of learning--exploration,…

  5. From interleukin-23 to T-helper 17 cells: human T-helper cell differentiation revisited.

    PubMed

    Boniface, Katia; Blom, Bianca; Liu, Yong-Jun; de Waal Malefyt, René

    2008-12-01

    Protracted inflammation leading to dysregulation of effector T-cell responses represents a common feature of a wide range of autoimmune diseases. The interleukin-12 (IL-12)/T-helper 1 (Th1) pathway was thought to be responsible for the pathogenesis of multiple chronic inflammatory diseases, including psoriasis, inflammatory bowel disease, arthritis, or multiple sclerosis, mainly through their production of interferon-gamma and its effects on macrophage activation and chemokine production. However, this initial concept of T-cell-mediated chronic inflammation required an adjustment with the discovery of an IL-12-related cytokine, designated IL-23. IL-23 was rapidly recognized for its involvement in the establishment of chronic inflammation and in the development of a Th cell subset producing IL-17, designated Th17, which is distinct from the previously reported Th1 and Th2 populations. This review aims to describe the characterization of IL-23 and its receptor, its biological activities, as well as its involvement in the development of human Th17 cells and autoimmunity.

  6. Family caregiving or caregiving alone: who helps the helper?

    PubMed

    Sims-Gould, Joanie; Martin-Matthews, Anne

    2007-01-01

    This study advances the understanding of family caregiving by examining the relationship between adult children caregivers and their helpers. Specifically, it focuses on examining "who helps whom" and extends analyses beyond the dyadic focus of caregiving in later life. The focus on helping and caregiving addresses the variety of contributions and responsibilities involving not only the caregiver who was the target respondent in this research, but also others identified as helpers in the provision of care. The data for this study are derived from the Work and Eldercare Research group of CARNET: The Canadian Aging Research Network. Secondary analysis of CARNET data focuses on data collected from 250 individuals with significant caregiving responsibilities for at least one older person. Findings extend Kahn & Antonucci's convoys of social support model (1981) and Cantor's model of social care (1991) by disentangling some of the dimensions of helping and caregiving, such as the distinction between direct and assistive help.

  7. Helper T cells and atherosclerosis: the cytokine web

    PubMed Central

    Baidya, S; Zeng, Q

    2005-01-01

    There is growing evidence regarding the importance of inflammation in the pathogenesis of atherosclerosis and its ultimate progression to the clinical syndromes. Recently there has been an increasing interest in the role of helper T (Th) cells in atherosclerosis. The Th cells act with the macrophages and the dendritic cells via the various cytokines in bringing about a variety of changes thus leading to the progression of atherosclerosis. Atherosclerotic lesions have been seen to have increased expression of type 1 helper T (TH1) cells together with increased levels of the Th1 related cytokines. It is mainly the cytokines involved with Th1 functioning that seem to show a prominent effect, with the whole process centred around interferon gamma, making it seem like every pathway and the cytokines involved lead to a final common pathway of interferon gamma secretion; the increase or decrease of which dictates the progression of atherosclerosis and its final manifestation as the clinical syndromes. PMID:16344296

  8. Alcoholics Anonymous-Related Helping and the Helper Therapy Principle

    PubMed Central

    Pagano, Maria E.; Post, Stephen G.; Johnson, Shannon M.

    2012-01-01

    The helper therapy principle (HTP) observes the helper’s health benefits derived from helping another with a shared malady. The HTP is embodied by the program of Alcoholics Anonymous as a method to diminish egocentrism as a root cause of addiction. This article reviews recent evidence of the HTP in alcohol populations, extends to populations with chronic conditions beyond addiction, and concludes with new directions of empirical inquiry. PMID:23525280

  9. Maintaining helper wellness and competence in a shared trauma reality.

    PubMed

    Halpern, James

    2016-01-01

    As shared trauma reality becomes more common in Israel and other countries, this commentary argues that we need more research to inform how to best assist mental health professionals who are both victims and helpers in the aftermath of traumatic events. Typical remedies for the occupational hazards of working with trauma survivors may not apply for those who are exposed to a prolonged terror threat. Research-informed self-care strategies need to be identified and practiced. PMID:27606048

  10. Communicating bad news: a model for emergency mental health helpers.

    PubMed

    Nardi, Thomas J; Keefe-Cooperman, Kathleen

    2006-01-01

    This article addresses the concerns of the messenger/helper who must convey tragic news to individuals and families. It offers a model to be used as a guide to ease the stress on both the deliverer and receiver of bad news. The model uses the mnemonic, PEWTER (Prepare, Evaluate, Warn, Tell, Emotional Response, Regroup), to represent the six components of the communication process. PMID:16944793

  11. Follicular helper T cell in immunity and autoimmunity.

    PubMed

    Mesquita, D; Cruvinel, W M; Resende, L S; Mesquita, F V; Silva, N P; Câmara, N O S; Andrade, L E C

    2016-01-01

    The traditional concept that effector T helper (Th) responses are mediated by Th1/Th2 cell subtypes has been broadened by the recent demonstration of two new effector T helper cells, the IL-17 producing cells (Th17) and the follicular helper T cells (Tfh). These new subsets have many features in common, such as the ability to produce IL-21 and to express the IL-23 receptor (IL23R), the inducible co-stimulatory molecule ICOS, and the transcription factor c-Maf, all of them essential for expansion and establishment of the final pool of both subsets. Tfh cells differ from Th17 by their ability to home to B cell areas in secondary lymphoid tissue through interactions mediated by the chemokine receptor CXCR5 and its ligand CXCL13. These CXCR5+ CD4+ T cells are considered an effector T cell type specialized in B cell help, with a transcriptional profile distinct from Th1 and Th2 cells. The role of Tfh cells and its primary product, IL-21, on B-cell activation and differentiation is essential for humoral immunity against infectious agents. However, when deregulated, Tfh cells could represent an important mechanism contributing to exacerbated humoral response and autoantibody production in autoimmune diseases. This review highlights the importance of Tfh cells by focusing on their biology and differentiation processes in the context of normal immune response to infectious microorganisms and their role in the pathogenesis of autoimmune diseases. PMID:27096200

  12. Convergent evolution of pathogenicity islands in helper cos phage interference.

    PubMed

    Carpena, Nuria; Manning, Keith A; Dokland, Terje; Marina, Alberto; Penadés, José R

    2016-11-01

    Staphylococcus aureus pathogenicity islands (SaPIs) are phage satellites that exploit the life cycle of their helper phages for their own benefit. Most SaPIs are packaged by their helper phages using a headful (pac) packaging mechanism. These SaPIs interfere with pac phage reproduction through a variety of strategies, including the redirection of phage capsid assembly to form small capsids, a process that depends on the expression of the SaPI-encoded cpmA and cpmB genes. Another SaPI subfamily is induced and packaged by cos-type phages, and although these cos SaPIs also block the life cycle of their inducing phages, the basis for this mechanism of interference remains to be deciphered. Here we have identified and characterized one mechanism by which the SaPIs interfere with cos phage reproduction. This mechanism depends on a SaPI-encoded gene, ccm, which encodes a protein involved in the production of small isometric capsids, compared with the prolate helper phage capsids. As the Ccm and CpmAB proteins are completely unrelated in sequence, this strategy represents a fascinating example of convergent evolution. Moreover, this result also indicates that the production of SaPI-sized particles is a widespread strategy of phage interference conserved during SaPI evolution.This article is part of the themed issue 'The new bacteriology'.

  13. Convergent evolution of pathogenicity islands in helper cos phage interference

    PubMed Central

    Manning, Keith A.; Dokland, Terje; Marina, Alberto

    2016-01-01

    Staphylococcus aureus pathogenicity islands (SaPIs) are phage satellites that exploit the life cycle of their helper phages for their own benefit. Most SaPIs are packaged by their helper phages using a headful (pac) packaging mechanism. These SaPIs interfere with pac phage reproduction through a variety of strategies, including the redirection of phage capsid assembly to form small capsids, a process that depends on the expression of the SaPI-encoded cpmA and cpmB genes. Another SaPI subfamily is induced and packaged by cos-type phages, and although these cos SaPIs also block the life cycle of their inducing phages, the basis for this mechanism of interference remains to be deciphered. Here we have identified and characterized one mechanism by which the SaPIs interfere with cos phage reproduction. This mechanism depends on a SaPI-encoded gene, ccm, which encodes a protein involved in the production of small isometric capsids, compared with the prolate helper phage capsids. As the Ccm and CpmAB proteins are completely unrelated in sequence, this strategy represents a fascinating example of convergent evolution. Moreover, this result also indicates that the production of SaPI-sized particles is a widespread strategy of phage interference conserved during SaPI evolution. This article is part of the themed issue ‘The new bacteriology’. PMID:27672154

  14. Convergent evolution of pathogenicity islands in helper cos phage interference.

    PubMed

    Carpena, Nuria; Manning, Keith A; Dokland, Terje; Marina, Alberto; Penadés, José R

    2016-11-01

    Staphylococcus aureus pathogenicity islands (SaPIs) are phage satellites that exploit the life cycle of their helper phages for their own benefit. Most SaPIs are packaged by their helper phages using a headful (pac) packaging mechanism. These SaPIs interfere with pac phage reproduction through a variety of strategies, including the redirection of phage capsid assembly to form small capsids, a process that depends on the expression of the SaPI-encoded cpmA and cpmB genes. Another SaPI subfamily is induced and packaged by cos-type phages, and although these cos SaPIs also block the life cycle of their inducing phages, the basis for this mechanism of interference remains to be deciphered. Here we have identified and characterized one mechanism by which the SaPIs interfere with cos phage reproduction. This mechanism depends on a SaPI-encoded gene, ccm, which encodes a protein involved in the production of small isometric capsids, compared with the prolate helper phage capsids. As the Ccm and CpmAB proteins are completely unrelated in sequence, this strategy represents a fascinating example of convergent evolution. Moreover, this result also indicates that the production of SaPI-sized particles is a widespread strategy of phage interference conserved during SaPI evolution.This article is part of the themed issue 'The new bacteriology'. PMID:27672154

  15. Follicular helper T cell in immunity and autoimmunity

    PubMed Central

    Mesquita, D.; Cruvinel, W.M.; Resende, L.S.; Mesquita, F.V.; Silva, N.P.; Câmara, N.O.S.; Andrade, L.E.C.

    2016-01-01

    The traditional concept that effector T helper (Th) responses are mediated by Th1/Th2 cell subtypes has been broadened by the recent demonstration of two new effector T helper cells, the IL-17 producing cells (Th17) and the follicular helper T cells (Tfh). These new subsets have many features in common, such as the ability to produce IL-21 and to express the IL-23 receptor (IL23R), the inducible co-stimulatory molecule ICOS, and the transcription factor c-Maf, all of them essential for expansion and establishment of the final pool of both subsets. Tfh cells differ from Th17 by their ability to home to B cell areas in secondary lymphoid tissue through interactions mediated by the chemokine receptor CXCR5 and its ligand CXCL13. These CXCR5+ CD4+ T cells are considered an effector T cell type specialized in B cell help, with a transcriptional profile distinct from Th1 and Th2 cells. The role of Tfh cells and its primary product, IL-21, on B-cell activation and differentiation is essential for humoral immunity against infectious agents. However, when deregulated, Tfh cells could represent an important mechanism contributing to exacerbated humoral response and autoantibody production in autoimmune diseases. This review highlights the importance of Tfh cells by focusing on their biology and differentiation processes in the context of normal immune response to infectious microorganisms and their role in the pathogenesis of autoimmune diseases. PMID:27096200

  16. T Helper1/T Helper2 Cells and Resistance/Susceptibility to Leishmania Infection: Is This Paradigm Still Relevant?

    PubMed Central

    Alexander, James; Brombacher, Frank

    2012-01-01

    Work in large part on Leishmania major in the 1980s identified two distinct apparently counter-regulatory CD4+ T cell populations, T helper (h)1 and Th2, that controlled resistance/susceptibility to infection respectively. However, the generation of IL-4−/− mice in the 1990s questioned the paramount role of this Th2 archetypal cytokine in the non-healing response to Leishmania infection. The more recent characterization of CD4+ T cell regulatory populations and further effector CD4+ T helper populations, Th17, Th9, and T follicular (f)h cells as well as the acknowledged plasticity in T helper cell function has further added to the complexity of host pathogen interactions. These interactions are complicated by the multiplicity of cells that respond to CD4+ T cell subset signatory cytokines, as well as the diversity of Leishmania species that are often subject to significantly different immune-regulatory controls. In this article we review current knowledge with regard to the role of CD4+ T cells and their products during Leishmania infection. In particular we update on our studies using conditional IL-4Rα gene-deficient mice that have allowed dissection of the cell interplay dictating the disease outcomes of the major Leishmania species infecting humans. PMID:22566961

  17. Resource Allocation Planning Helper (RALPH): Lessons learned

    NASA Technical Reports Server (NTRS)

    Durham, Ralph; Reilly, Norman B.; Springer, Joe B.

    1990-01-01

    The current task of Resource Allocation Process includes the planning and apportionment of JPL's Ground Data System composed of the Deep Space Network and Mission Control and Computing Center facilities. The addition of the data driven, rule based planning system, RALPH, has expanded the planning horizon from 8 weeks to 10 years and has resulted in large labor savings. Use of the system has also resulted in important improvements in science return through enhanced resource utilization. In addition, RALPH has been instrumental in supporting rapid turn around for an increased volume of special what if studies. The status of RALPH is briefly reviewed and important lessons learned from the creation of an highly functional design team are focused on through an evolutionary design and implementation period in which an AI shell was selected, prototyped, and ultimately abandoned, and through the fundamental changes to the very process that spawned the tool kit. Principal topics include proper integration of software tools within the planning environment, transition from prototype to delivered to delivered software, changes in the planning methodology as a result of evolving software capabilities and creation of the ability to develop and process generic requirements to allow planning flexibility.

  18. Idiotype-recognizing T helper cells that are not idiotype specific.

    PubMed

    McNamara, M; Kohler, H

    1983-09-01

    In this study T helper cells that recognize idiotypes as carriers for a hapten-specific B cell response were analyzed under limiting dilution conditions. T helper cells, induced by phosphorylcholine-hemocyanin (PC-Hy) priming, recognize trinitrophenylated TEPC-15 and MOPC-167 (TNP-T15, TNP-167) equally well. Limiting dilution analysis indicates identical frequencies of helper cells for TNP-T15 and TNP-167. Double immunization protocols using TNP-T15 and TNP-167 fail to demonstrate additive effects. Inhibition of carrier recognition in vitro using free hapten, PC, and unconjugated T15 or M167 indicates identical specificities of helper cells for T15 and M167. Collectively, these results provide strong evidence that PC-Hy priming induces only one population of idiotype-recognizing helper cells that are unable to distinguish between the T15 and the M167 idiotopes. The helper cell induction circuit was further analyzed. PC-Hy priming induces T15/167-specific helper T cells in X-linked immune defect-expressing F1 mice. This indicates that a B cell response to PC is not required to induce idiotype-recognizing T cells. Adoptive cotransfer of B cells from PC-Hy-primed mice together with normal T cells fails to induce idiotype-recognizing T cells. These results indicate the existence of a T helper1-T helper2 induction loop. In this scheme, the T helper1 cell carries T15-like receptors and the T helper2 cells, anti-T15-like receptors. Monoclonal antiidiotypic antibodies specific for T15 also induce a T15/167-recognizing T helper cell population. This finding demonstrates that idiotope-specific priming induces non-idiotype-specific T cells. Evidently, the idiotypic T cell network is based on a different selection of idiotope determinants than the selection of the B cell idiotype network.

  19. [Examination of physical and psychological health conditions and the influence factors of home helpers].

    PubMed

    Ashitomi, Ikuya

    2005-12-01

    The primary aim of this study was to examine the physical and psychological health conditions and the influence factors of home helpers. The secondary aim was to suggest a stress management system for home helpers. Self-report questionnaires were distributed to 1147 home helpers who were with home health care agencies in Kitakyushu-city. Responses from 979 home helpers were received, yielding a response rate of 85.5%. A total of 967 home helpers (excluding 12 male home helpers) were used for analysis. The Japanese version of the General Health Questionnaire 28 (GHQ-28) was used to measure the physical and psychological health conditions of the home helpers. In addition, as an influence factor, stress coping was measured by the Lazarus-type Stress Coping Inventory (SCI). Home helpers also filled out the Ego Aptitude Scale (EAS) as a personality measure. Furthermore, the subjects were asked questions about individual background factors, including age, marital status, working hours, years working as a home helper, type of home helper, job satisfaction, job continuation and awareness of stress. The data were analyzed using the Statistical Package for the Social Sciences (SPSS 11.5 J). The groups of full-time or part-time home helpers showed GHQ-28 total scores of 6.86 +/- 5.48 and 5.21 +/- 4.97 (Mean +/- SD): part-time home helpers had significantly higher scores than full-time home helpers. The GHQ-28 measure indicated that about 20% of home helpers had physical and psychological symptoms, and about 4% had mid-level depressive symptoms. About half of the subjects were aware of stress. There were significant negative correlations between GHQ-28 total scores and age. Also, there was a statistically significant relation between GHQ-28 and job satisfaction, awareness of stress, type of stress coping and individual personality. Furthermore, there was a statistically significant relation between GHQ-28 and the confrontive coping type, positive reappraisal of SCI, and

  20. T-Helper Cytokine Profiles in Patients with Kawasaki Disease

    PubMed Central

    Lee, Sang Bum; Kim, Young Hyun; Hyun, Myung Chul; Kim, Yeo Hyang; Kim, Hee Sun

    2015-01-01

    Background and Objectives Kawasaki disease is an acute systemic vasculitis of which pathogenesis suspected is caused by immune dysregulation. The goal of this study is to evaluate the activation pattern of T helper cell type 1 (Th1) and T helper cell type 2 (Th2) in patients with Kawasaki disease. Subjects and Methods Prospective study of 60 patients (male 36, female 24) with diagnosis of Kawasaki disease were enrolled. One hundred and eighty blood samples from these patients were collected according to the different clinical stages {before initial intravenous immunoglobulin (IVIG), 5 days after initial IVIG, 2 months after initial IVIG}. The plasma level of Th1 cytokines; interferon-gamma (IFN-γ) & interleukin (IL)-2 and Th2 cytokines; IL-4 & IL-10 were measured by enzyme-liked immunosorbent assay. Results In all patients, the plasma level of Th1 cytokines (IFN-γ, IL-2) and Th2 cytokines (IL-4 and IL-10) were markedly elevated during the acute stage of Kawasaki disease. Since then, the plasma level of all these cytokines decreased significantly along with the process of clinical stages. Regardless of the existence of coronary artery lesion or no response to initial IVIG treatment, there were no significant differences between them. Conclusion These data suggest that both Th1 and Th2 cells may be activated simultaneously during the acute stage of Kawasaki disease. Further studies are therefore required to establish the difference of activation pattern of T helper cells between Kawasaki disease and other inflammatory diseases. PMID:26617655

  1. Antagonistic effect of helpers on breeding male and female survival in a cooperatively breeding bird

    PubMed Central

    Paquet, Matthieu; Doutrelant, Claire; Hatchwell, Ben J; Spottiswoode, Claire N; Covas, Rita

    2015-01-01

    1. Cooperatively breeding species are typically long lived and hence, according to theory, are expected to maximize their lifetime reproductive success through maximizing survival. Under these circumstances, the presence of helpers could be used to lighten the effort of current reproduction for parents to achieve higher survival. 2. In addition, individuals of different sexes and ages may follow different strategies, but whether male and female breeders and individuals of different ages benefit differently from the presence of helpers has often been overlooked. Moreover, only one study that investigated the relationship between parental survival and the presence of helpers used capture–mark–recapture analyses (CMR). These methods are important since they allow us to account for the non-detection of individuals that are alive in the population but not detected, and thus, the effects on survival and recapture probability to be disentangled. 3. Here, we used multi-event CMR methods to investigate whether the number of helpers was associated with an increase in survival probability for male and female breeders of different ages in the sociable weaver Philetairus socius. In this species, both sexes reduce their feeding rate in the presence of helpers. We therefore predicted that the presence of helpers should increase the breeders' survival in both sexes, especially early in life when individuals potentially have more future breeding opportunities. In addition, sociable weaver females reduce their investment in eggs in the presence of helpers, so we predicted a stronger effect of helpers on female than male survival. 4. As expected we found that females had a higher survival probability when breeding with more helpers. Unexpectedly, however, male survival probability decreased with increasing number of helpers. This antagonistic effect diminished as the breeders grew older. 5. These results illustrate the complexity of fitness costs and benefits underlying

  2. T Helper Cell Subsets in Clinical Manifestations of Psoriasis

    PubMed Central

    Diani, Marco; Altomare, Gianfranco

    2016-01-01

    Psoriasis is a chronic inflammatory skin disease, which is associated with systemic inflammation and comorbidities, such as psoriatic arthritis and cardiovascular diseases. The autoimmune nature of psoriasis has been established only recently, conferring a central role to epidermal CD8 T cells recognizing self-epitopes in the initial phase of the disease. Different subsets of helper cells have also been reported as key players in the psoriasis pathogenesis. Here, we reviewed the knowledge on the role of each subset in the psoriatic cascade and in the different clinical manifestations of the disease. We will discuss the role of Th1 and Th17 cells in the initiation and in the amplification phase of cutaneous inflammation. Moreover, we will discuss the recently proposed role of tissue resident Th22 cells in disease memory in sites of recurrent psoriasis and the possible involvement of Th9 cells. Finally, we will discuss the hypothesis of a link between T helper cell subsets recirculating from the skin and the systemic manifestations of psoriasis. PMID:27595115

  3. T Helper Cell Subsets in Clinical Manifestations of Psoriasis

    PubMed Central

    Diani, Marco; Altomare, Gianfranco

    2016-01-01

    Psoriasis is a chronic inflammatory skin disease, which is associated with systemic inflammation and comorbidities, such as psoriatic arthritis and cardiovascular diseases. The autoimmune nature of psoriasis has been established only recently, conferring a central role to epidermal CD8 T cells recognizing self-epitopes in the initial phase of the disease. Different subsets of helper cells have also been reported as key players in the psoriasis pathogenesis. Here, we reviewed the knowledge on the role of each subset in the psoriatic cascade and in the different clinical manifestations of the disease. We will discuss the role of Th1 and Th17 cells in the initiation and in the amplification phase of cutaneous inflammation. Moreover, we will discuss the recently proposed role of tissue resident Th22 cells in disease memory in sites of recurrent psoriasis and the possible involvement of Th9 cells. Finally, we will discuss the hypothesis of a link between T helper cell subsets recirculating from the skin and the systemic manifestations of psoriasis.

  4. Helper-independent transformation by unintegrated Harvey sarcoma virus DNA.

    PubMed

    Lowy, D R; Rands, E; Scolnick, E M

    1978-05-01

    We have studied the unintegrated infectious DNA of Harvey sarcoma virus (Ha-SV) and Moloney leukemia virus (Mo-MuLV). The source of infectious viral DNA was the Hirt supernatant fraction from cells acutely infected with Ha-SV and Mo-MuLV. To obtain a direct quantitative assay for infectious viral DNA, recipient mouse cells were first exposed to calcium phosphate-precipitated viral DNA and then treated with dimethyl sulfoxide. Infectivity was monitored by focus formation for Ha-SV and XC plaque formation for Mo-MuLV. The viral DNA titration pattern followed single-hit kinetics for both foci and plaques, indicating that a single molecule carried information for each function. Focus-forming and plaque-forming activity were present in different molecules, since these two biological activities could be separated from each other by agarose gel electrophoresis. The focus-forming molecule was linear DNA with a molecular weight of about 4 x 10(6) daltons. The focus-forming activity of the viral DNA was sensitive to EcoRI and resistant to XhoI restriction endonucleases, whereas the plaque-forming activity was resistant to EcoRI and sensitive to XhoI. The generation of helper-independent foci indicates that Ha-SV DNA can transform mouse cells in the absence of helper virus or its proteins.

  5. Vaccine efficacy and T helper cell differentiation change with aging

    PubMed Central

    Masters, April R.; Hopkins, Jacob W.; Eaton, Sheri M.; Smiley, Stephen T.; Haynes, Laura

    2016-01-01

    Influenza and pneumonia are leading causes of death in elderly populations. With age, there is an increased inflammatory response and slower viral clearance during influenza infection which increases the risk of extended illness and mortality. Here we employ a preclinical murine model of influenza infection to examine the protective capacity of vaccination with influenza nucleoprotein (NP). While NP vaccination reduces influenza-induced lung inflammation in young mice, aged mice do not show this reduction, but are protected from influenza-induced mortality. Aged mice do make a significant amount of NP-specific IgG and adoptive transfer experiments show that NP antibody can protect from death but cannot reduce lung inflammation. Furthermore, young but not aged vaccinated mice generate significant numbers of NP-specific T cells following subsequent infection and few of these T cells are found in aged lungs early during infection. Importantly, aged CD4 T cells have a propensity to differentiate towards a T follicular helper (Tfh) phenotype rather than a T helper 1 (Th1) phenotype that predominates in the young. Since Th1 cells are important in viral clearance, reduced Th1 differentiation in the aged is critical and could account for some or all of the age-related differences in vaccine responses and infection resolution. PMID:27177221

  6. T Helper Cell Subsets in Clinical Manifestations of Psoriasis.

    PubMed

    Diani, Marco; Altomare, Gianfranco; Reali, Eva

    2016-01-01

    Psoriasis is a chronic inflammatory skin disease, which is associated with systemic inflammation and comorbidities, such as psoriatic arthritis and cardiovascular diseases. The autoimmune nature of psoriasis has been established only recently, conferring a central role to epidermal CD8 T cells recognizing self-epitopes in the initial phase of the disease. Different subsets of helper cells have also been reported as key players in the psoriasis pathogenesis. Here, we reviewed the knowledge on the role of each subset in the psoriatic cascade and in the different clinical manifestations of the disease. We will discuss the role of Th1 and Th17 cells in the initiation and in the amplification phase of cutaneous inflammation. Moreover, we will discuss the recently proposed role of tissue resident Th22 cells in disease memory in sites of recurrent psoriasis and the possible involvement of Th9 cells. Finally, we will discuss the hypothesis of a link between T helper cell subsets recirculating from the skin and the systemic manifestations of psoriasis. PMID:27595115

  7. Helper effects on pup lifetime fitness in the cooperatively breeding red wolf (Canis rufus)

    PubMed Central

    Sparkman, Amanda M.; Adams, Jennifer; Beyer, Arthur; Steury, Todd D.; Waits, Lisette; Murray, Dennis L.

    2011-01-01

    The evolutionary maintenance of cooperative breeding systems is thought to be a function of relative costs and benefits to breeders, helpers and juveniles. Beneficial effects of helpers on early-life survivorship and performance have been established in several species, but lifetime fitness benefits and/or costs of being helped remain unclear, particularly for long-lived species. We tested for effects of helpers on early- and late-life traits in a population of reintroduced red wolves (Canis rufus), while controlling for ecological variables such as home-range size and population density. We found that the presence of helpers in family groups was positively correlated with pup mass and survival at low population density, but negatively correlated with mass/size at high density, with no relation to survival. Interestingly, mass/size differences persisted into adulthood for both sexes. While the presence of helpers did not advance age at first reproduction for pups of either sex, females appeared to garner long-term fitness benefits from helpers through later age at last reproduction, longer reproductive lifespan and a greater number of lifetime reproductive events, which translated to higher lifetime reproductive success. In contrast, males with helpers exhibited diminished lifetime reproductive performance. Our findings suggest that while helper presence may have beneficial short-term effects in some ecological contexts, it may also incur long-term sex-dependent costs with critical ramifications for lifetime fitness. PMID:20961897

  8. Genome sequence of the mycorrhizal helper bacterium Pseudomonas fluorescens BBc6R8

    SciTech Connect

    Deveau, Aurelie; Grob, Harald; Morin, Emmanuelle; Karpinets, Tatiana V; Utturkar, Sagar M; Mehnaz, Samina; Kurz, Sven; Martin, Francis; Frey-Klett, Pascale; Labbe, Jessy L

    2014-01-01

    We report the draft genome sequence of the mycorrhiza helper bacterium Pseudomonas fluorescens strain BBc6R8 . Several traits which could be involved in the mycorrhiza helper ability of the bacterial strain such as multiple secretion systems, auxin metabolism and phosphate mobilization were evidenced in the genome.

  9. Helper effects on pup lifetime fitness in the cooperatively breeding red wolf (Canis rufus).

    PubMed

    Sparkman, Amanda M; Adams, Jennifer; Beyer, Arthur; Steury, Todd D; Waits, Lisette; Murray, Dennis L

    2011-05-01

    The evolutionary maintenance of cooperative breeding systems is thought to be a function of relative costs and benefits to breeders, helpers and juveniles. Beneficial effects of helpers on early-life survivorship and performance have been established in several species, but lifetime fitness benefits and/or costs of being helped remain unclear, particularly for long-lived species. We tested for effects of helpers on early- and late-life traits in a population of reintroduced red wolves (Canis rufus), while controlling for ecological variables such as home-range size and population density. We found that the presence of helpers in family groups was positively correlated with pup mass and survival at low population density, but negatively correlated with mass/size at high density, with no relation to survival. Interestingly, mass/size differences persisted into adulthood for both sexes. While the presence of helpers did not advance age at first reproduction for pups of either sex, females appeared to garner long-term fitness benefits from helpers through later age at last reproduction, longer reproductive lifespan and a greater number of lifetime reproductive events, which translated to higher lifetime reproductive success. In contrast, males with helpers exhibited diminished lifetime reproductive performance. Our findings suggest that while helper presence may have beneficial short-term effects in some ecological contexts, it may also incur long-term sex-dependent costs with critical ramifications for lifetime fitness.

  10. Effects of Helper and Caller Characteristics on the Process and Outcome of Telephone Crisis Intervention.

    ERIC Educational Resources Information Center

    Echterling, Lennis G.; Hartsough, Don M.

    Research has examined the relationship of characteristics of crisis telephone workers to their performance. The influence and interaction of the characteristics of both the helper and caller on the telephone crisis intervention and outcome were explored for a sample of 59 calls to a crisis center. Data about the telephone helper (age, sex,…

  11. Helper virus-mediated downregulation of transgene expression permits production of recalcitrant helper-dependent adenoviral vector

    PubMed Central

    Palmer, Donna J; Grove, Nathan C; Ng, Philip

    2016-01-01

    Helper-dependent adenoviral vectors (HDAd) that express certain transgene products are impossible to produce because the transgene product is toxic to the producer cells, especially when made in large amounts during vector production. Downregulating transgene expression from the HDAd during vector production is a way to solve this problem. In this report, we show that this can be accomplished by inserting the target sequence for the adenoviral VA RNAI into the 3’ untranslated region of the expression cassette in the HDAd. Thus during vector production, when the producer cells are coinfected with both the helper virus (HV) and the HDAd, the VA RNAI produced by the HV will target the transgene mRNA from the HDAd via the endogenous cellular RNAi pathway. Once the HDAd is produced and purified, transduction of the target cells results in unimpeded transgene expression because of the absence of HV. This simple and universal strategy permits for the robust production of otherwise recalcitrant HDAds. PMID:27331077

  12. T Follicular Helper Cell Plasticity Shapes Pathogenic T Helper 2 Cell-Mediated Immunity to Inhaled House Dust Mite.

    PubMed

    Ballesteros-Tato, André; Randall, Troy D; Lund, Frances E; Spolski, Rosanne; Leonard, Warren J; León, Beatriz

    2016-02-16

    Exposure to environmental antigens, such as house dust mite (HDM), often leads to T helper 2 (Th2) cell-driven allergic responses. However, the mechanisms underlying the development of these responses are incompletely understood. We found that the initial exposure to HDM did not lead to Th2 cell development but instead promoted the formation of interleukin-4 (IL-4)-committed T follicular helper (Tfh) cells. Following challenge exposure to HDM, Tfh cells differentiated into IL-4 and IL-13 double-producing Th2 cells that accumulated in the lung and recruited eosinophils. B cells were required to expand IL-4-committed Tfh cells during the sensitization phase, but did not directly contribute to disease. Impairment of Tfh cell responses during the sensitization phase or Tfh cell depletion prevented Th2 cell-mediated responses following challenge. Thus, our data demonstrate that Tfh cells are precursors of HDM-specific Th2 cells and reveal an unexpected role of B cells and Tfh cells in the pathogenesis of allergic asthma.

  13. In situ activation of helper T cells in the lung.

    PubMed

    Raju, B; Tung, C F; Cheng, D; Yousefzadeh, N; Condos, R; Rom, W N; Tse, D B

    2001-08-01

    To better understand the lung and systemic responses of helper T cells mediating memory immunity to Mycobacterium tuberculosis, we used three- and four-color flow cytometry to study the surface phenotype of CD4(+) lymphocytes. Bronchoalveolar lavage (BAL) fluid and peripheral blood (PB) samples were obtained from a total of 25 subjects, including 10 tuberculosis (TB)-infected subjects, 8 purified-protein-derivative-negative subjects, and 7 purified-protein-derivative-positive subjects. In marked contrast to CD4(+) lymphocytes from PB (9% +/- 5% expressing CD45RA and CD29), the majority (55% +/- 16%) of CD4(+) lymphocytes in BAL (ALs) simultaneously expressed CD45RA, a naïve T-cell marker, and CD29, members of the very late activation family. Further evaluation revealed that CD4(+) ALs expressed both CD45RA and CD45RO, a memory T-cell marker. In addition, the proportion of CD4(+) lymphocytes expressing CD69, an early activation marker, was drastically increased in BAL fluid (83% +/- 9%) compared to PB (1% +/- 1%), whereas no significant difference was seen in the expression of CD25, the low-affinity interleukin 2 receptor (34% +/- 15% versus 40% +/- 16%). More importantly, we identified a minor population of CD69(bright) CD25(bright) CD4(+) lymphocytes in BAL (10% +/- 6%) that were consistently absent from PB (1% +/- 1%). Thus, CD4(+) lymphocytes in the lung paradoxically coexpress surface molecules characteristic of naïve and memory helper T cells as well as surface molecules commonly associated with early and late stages of activation. No difference was observed for ALs obtained from TB-infected and uninfected lung segments in this regard. It remains to be determined if these surface molecules are induced by the alveolar environment or if CD4(+) lymphocytes coexpressing this unusual combination of surface molecules are selectively recruited from the circulation. Our data suggest that ex vivo experiments on helper T-cell subsets that display distinctive

  14. Regulating IL-9 transcription in T helper cells

    PubMed Central

    Perumal, Narayanan B.; Kaplan, Mark H.

    2011-01-01

    T helper cells are critical for the development of immunity to infections and inflammatory disease. The acquisition of specific cytokine-secreting profiles, primed by the cytokine microenvironment, is required for effector function of Th cells. The most recent addition to the growing list of effector subsets are Th9 cells that secrete IL-9. In this article we propose a model for the transcriptional regulation of the Il9 gene in IL-9-expressing T cells and the relatedness of this subset to other Th phenotypes. We suggest that transcription factors restricted to certain Th subsets, and common among several subsets, may play a role in the plasticity of Th9 cells. PMID:21371941

  15. [Helpless helpers? Health and disease of physicians in historical perspective].

    PubMed

    Schäfer, Daniel

    2015-12-01

    Seen from a historical perspective the health and illness of a physician is not at all his private matter; they have an impact on his relationship with his patients and the public. Drawing on sources from Graeco-Roman times up to now information referring to this subject is scarce and heterogeneous. However, it is possible to differentiate between three main concepts encompassing various periods: In those reaching approximately until 1700 the physician's personal health and recovery were his credentials of his art of healing. In the following 250 years he increasingly stylized himself as a victim in the service of his patients and science. After 1970 helpless helpers are threatened by mental illness. PMID:26676477

  16. Transcriptional and epigenetic networks of helper T and innate lymphoid cells.

    PubMed

    Shih, Han-Yu; Sciumè, Giuseppe; Poholek, Amanda C; Vahedi, Golnaz; Hirahara, Kiyoshi; Villarino, Alejandro V; Bonelli, Michael; Bosselut, Remy; Kanno, Yuka; Muljo, Stefan A; O'Shea, John J

    2014-09-01

    The discovery of the specification of CD4(+) helper T cells to discrete effector 'lineages' represented a watershed event in conceptualizing mechanisms of host defense and immunoregulation. However, our appreciation for the actual complexity of helper T-cell subsets continues unabated. Just as the Sami language of Scandinavia has 1000 different words for reindeer, immunologists recognize the range of fates available for a CD4(+) T cell is numerous and may be underestimated. Added to the crowded scene for helper T-cell subsets is the continuously growing family of innate lymphoid cells (ILCs), endowed with common effector responses and the previously defined 'master regulators' for CD4(+) helper T-cell subsets are also shared by ILC subsets. Within the context of this extraordinary complexity are concomitant advances in the understanding of transcriptomes and epigenomes. So what do terms like 'lineage commitment' and helper T-cell 'specification' mean in the early 21st century? How do we put all of this together in a coherent conceptual framework? It would be arrogant to assume that we have a sophisticated enough understanding to seriously answer these questions. Instead, we review the current status of the flexibility of helper T-cell responses in relation to their genetic regulatory networks and epigenetic landscapes. Recent data have provided major surprises as to what master regulators can or cannot do, how they interact with other transcription factors and impact global genome-wide changes, and how all these factors come together to influence helper cell function. PMID:25123275

  17. BCL6 interacting corepressor contributes to germinal center T follicular helper cell formation and B cell helper function

    PubMed Central

    Yang, Jessica A.; Tubo, Noah J.; Gearhart, Micah D.; Bardwell, Vivian J.; Jenkins, Marc K.

    2015-01-01

    CD4+ germinal center (GC) T follicular helper (GC-Tfh) cells help B cells become long-lived plasma cells and memory cells. The transcriptional repressor BCL6 plays a key role in GC-Tfh formation by inhibiting the expression of genes that promote differentiation into other lineages. We determined whether BCOR, a component of a Polycomb repressive complex that interacts with the BCL6 BTB domain, influences GC-Tfh differentiation. T cell-targeted BCOR deficiency led to a substantial loss of peptide:MHCII-specific GC-Tfh cells following Listeria monocytogenes infection and a 2-fold decrease following immunization with a peptide in CFA. The reduction in GC-Tfh cells was associated with diminished plasma cell and GC B cell formation. Thus, T cell-expressed BCOR is critical for optimal GC-Tfh differentiation and humoral immunity. PMID:25964495

  18. Helper activity by human large granular lymphocytes in in vitro immunoglobulin synthesis.

    PubMed

    Rodriguez, M A; Blanca, I; Baroja, M L; Arama, S; Leon-Ponte, M; Abadi, I; Bianco, N E

    1987-09-01

    In the present study we have examined the effect of human large granular lymphocytes (LGL) from healthy donors on Ig synthesis by autologous B lymphocytes. The results showed that this cell population has a consistent helper activity in pokeweed mitogen-activated cultures even when added at very low numbers. LGL can mediate their effect by secreting soluble helper factors capable of modulating B-cell responses as evidenced by the enhancement of IgG and IgM production by supernatants obtained from LGL cultures. Preincubation with interferon gamma further potentiated the helper activity by LGL.

  19. Incorporating Natural Helpers to Address Service Disparities for Young Children with Conduct Problems

    PubMed Central

    Acevedo-Polakovich, I. David; Niec, Larissa N.; Barnet, Miya L.; Bell, Katrina M.

    2013-01-01

    In response to the high levels of unmet need among historically underserved young children with conduct problems, this paper outlines some of the key issues involved in incorporating natural helpers into the delivery of parenting interventions for the treatment of conduct problems among historically underserved children. Strategies for the selection and training of natural helpers are discussed along with challenges that might be encountered in these processes. Directions for future research are also highlighted. With appropriate selection and training procedures in place, natural helpers may increase the accessibility of services for children and families and foster the reduction of service disparities. PMID:24729649

  20. T Helper 1 and T Helper 2 Cytokines Differentially Modulate Expression of Filaggrin and its Processing Proteases in Human Keratinocytes

    PubMed Central

    Di, Zheng-Hong; Ma, Lei; Qi, Rui-Qun; Sun, Xiao-Dong; Huo, Wei; Zhang, Li; Lyu, Ya-Ni; Hong, Yu-Xiao; Chen, Hong-Duo; Gao, Xing-Hua

    2016-01-01

    Background: Atopic dermatitis (AD) is characterized by defective skin barrier and imbalance in T helper 1/T helper 2 (Th1/Th2) cytokine expression. Filaggrin (FLG) is the key protein to maintaining skin barrier function. Recent studies indicated that Th1/Th2 cytokines influence FLG expression in keratinocytes. However, the role of Th1/Th2 cytokines on FLG processing is not substantially documented. Our aim was to investigate the impact of Th1/Th2 cytokines on FLG processing. Methods: HaCaT cells and normal human keratinocytes were cultured in low and high calcium media and stimulated by either interleukin (IL)-4, 13 or interferon-γ (IFN-γ). FLG, its major processing proteases and key protease inhibitor lymphoepithelial Kazal-type-related inhibitor (LEKTI) were measured by both real-time quantitative polymerase chain reaction and Western blotting. Their expression was also evaluated in acute and chronic AD lesions by immunohistochemistry. Results: IL-4/13 significantly reduced, while IFN-γ significantly up-regulated FLG expression. IL-4/13 significantly increased, whereas IFN-γ significantly decreased the expression of kallikreins 5 and 7, matriptase and channel-activating serine protease 1. On the contrary, IL-4/13 significantly decreased, while IFN-γ increased the expression of LEKTI and caspase-14. Similar trends were observed in AD lesions. Conclusions: Our results suggested that Th1/Th2 cytokines differentially regulated the expression of major FLG processing enzymes. The imbalance between Th1 and Th2 polarized immune response seems to extend to FLG homeostasis, through the network of FLG processing enzymes. PMID:26831231

  1. Site-1 protease is required for cartilage development in zebrafish.

    PubMed

    Schlombs, Kornelia; Wagner, Thomas; Scheel, Jochen

    2003-11-25

    gonzo (goz) is a zebrafish mutant with defects in cartilage formation. The goz phenotype comprises cartilage matrix defects and irregular chondrocyte morphology. Expression of endoderm, mesoderm, and cartilage marker genes is, however, normal, indicating a defect in chondrocyte morphogenesis. The mutated gene responsible for the goz phenotype, identified by positional cloning and confirmed by phosphomorpholino knockdown, encodes zebrafish site-1 protease (s1p). S1P has been shown to process and activate sterol regulatory element-binding proteins (SREBPs), which regulate expression of key enzymes of lipid biosynthesis or transport. This finding is consistent with the abnormal distribution of lipids in goz embryos. Knockdown of site-2 protease, which is also involved in activation of SREBPs, results in similar lipid and cartilage phenotypes as S1P knockdown. However, knockdown of SREBP cleavage-activating protein, which forms a complex with SREBP and is essential for S1P cleavage, results only in lipid phenotypes, whereas cartilage appears normal. This indicates that the cartilage phenoptypes of goz are caused independently of the lipid defects. PMID:14612568

  2. Site-1 protease is required for cartilage development in zebrafish

    PubMed Central

    Schlombs, Kornelia; Wagner, Thomas; Scheel, Jochen

    2003-01-01

    gonzo (goz) is a zebrafish mutant with defects in cartilage formation. The goz phenotype comprises cartilage matrix defects and irregular chondrocyte morphology. Expression of endoderm, mesoderm, and cartilage marker genes is, however, normal, indicating a defect in chondrocyte morphogenesis. The mutated gene responsible for the goz phenotype, identified by positional cloning and confirmed by phosphomorpholino knockdown, encodes zebrafish site-1 protease (s1p). S1P has been shown to process and activate sterol regulatory element-binding proteins (SREBPs), which regulate expression of key enzymes of lipid biosynthesis or transport. This finding is consistent with the abnormal distribution of lipids in goz embryos. Knockdown of site-2 protease, which is also involved in activation of SREBPs, results in similar lipid and cartilage phenotypes as S1P knockdown. However, knockdown of SREBP cleavage-activating protein, which forms a complex with SREBP and is essential for S1P cleavage, results only in lipid phenotypes, whereas cartilage appears normal. This indicates that the cartilage phenoptypes of goz are caused independently of the lipid defects. PMID:14612568

  3. Tailored immune responses: novel effector helper T cell subsets in protective immunity.

    PubMed

    Kara, Ervin E; Comerford, Iain; Fenix, Kevin A; Bastow, Cameron R; Gregor, Carly E; McKenzie, Duncan R; McColl, Shaun R

    2014-02-01

    Differentiation of naïve CD4⁺ cells into functionally distinct effector helper T cell subsets, characterised by distinct "cytokine signatures," is a cardinal strategy employed by the mammalian immune system to efficiently deal with the rapidly evolving array of pathogenic microorganisms encountered by the host. Since the T(H)1/T(H)2 paradigm was first described by Mosmann and Coffman, research in the field of helper T cell biology has grown exponentially with seven functionally unique subsets having now been described. In this review, recent insights into the molecular mechanisms that govern differentiation and function of effector helper T cell subsets will be discussed in the context of microbial infections, with a focus on how these different helper T cell subsets orchestrate immune responses tailored to combat the nature of the pathogenic threat encountered.

  4. Identification of novel helper epitope peptides of Survivin cancer-associated antigen applicable to developing helper/killer-hybrid epitope long peptide cancer vaccine.

    PubMed

    Ohtake, Junya; Ohkuri, Takayuki; Togashi, Yuji; Kitamura, Hidemitsu; Okuno, Kiyotaka; Nishimura, Takashi

    2014-09-01

    We identified novel helper epitope peptides of Survivin cancer antigen, which are presented to both HLA-DRB1*01:01 and DQB1*06:01. The helper epitope also contained three distinct Survivin-killer epitopes presented to HLA-A*02:01 and A*24:02. This 19 amino-acids epitope peptide (SU18) induced weak responses of Survivin-specific CD4(+) and CD8(+) T cells though it contained both helper and killer epitopes. To enhance the vaccine efficacy, we synthesized a long peptide by conjugating SU18 peptide and another DR53-restricted helper epitope peptide (SU22; 12 amino-acids) using glycine-linker. We designated this artificial 40 amino-acids long peptide containing two helper and three killer epitopes as Survivin-helper/killer-hybrid epitope long peptide (Survivin-H/K-HELP). Survivin-H/K-HELP allowed superior activation of IFN-γ-producing CD4(+) Th1 cells and CD8(+) Tc1 cells compared with the mixture of its component peptides (SU18 and SU22) in the presence of OK-432-treated monocyte-derived DC (Mo-DC). Survivin-H/K-HELP-pulsed Mo-DC pretreated with OK-432 also exhibited sustained antigen-presentation capability of stimulating Survivin-specific Th1 cells compared with Mo-DC pulsed with a mixture of SU18 and SU22 short peptides. Moreover, we demonstrated that Survivin-H/K-HELP induced a complete response in a breast cancer patient with the induction of cellular and humoral immune responses. Thus, we believe that an artificially synthesized Survivin-H/K-HELP will become an innovative cancer vaccine.

  5. Ambivalent helpers and unhealthy choices: public health practitioners' narratives of Indigenous ill-health.

    PubMed

    Kowal, Emma; Paradies, Yin

    2005-03-01

    Public health practitioners in Australian indigenous health work in a complex political environment. Public health training is limited in providing them with conceptual tools needed to unpack the postcolonial nexus of 'fourth-world' health. A workshop was designed by the authors to facilitate critical reflection on how the concepts of race and culture are used in constructions of indigenous ill-health. It was attended by researchers, students, clinicians and bureaucrats working in public health in northern Australia. A thematic analysis of the workshop minutes provided insight into public health practitioners' narratives of Indigenous ill-health. The major themes that emerged included tension between structure and agency and between sameness and difference, and ambivalence surrounding the 'helper' identity of public health practitioners. We suggest that these narratives can be understood as attempts to maintain the moral integrity of both Indigenous people and practitioners. This task is necessitated by the specter of cultural relativism intrinsic to contemporary liberal discourses of multiculturalism that attempt to reconcile the universal rights of the citizen with the special rights of minority groups. We argue that the concepts of self-determination and neocolonialism mark the spaces where universal and particular discourses overlap and clash. Practitioners who seek to escape neocolonialism must inhabit only the discursive space of public health congruent with self-determination, leaving them in a bind common to many postcolonial situations. They must relieve the ill-health of indigenous people without acting upon them; change them without declaring that change is required.

  6. Distribution and functional characteristics of antigen-specific helper T cells arising after Peyer's patch immunization.

    PubMed Central

    Dunkley, M L; Husband, A J

    1987-01-01

    Antigen-specific T-helper cells for IgA responses arise in Peyer's patches (PP) following their immunization by subserosal injection of keyhole limpet haemocyanin (KLH). These are of the W3/25 phenotype and the W3/25 receptor is shown here to be involved in their helper function. These cells originate in PP and migrate via mesenteric lymph nodes (MLN) to thoracic duct lymph, although the MLN appear to be unnecessary for the induction or maturation of antigen-specific helper cells collected in thoracic duct lymph after intra-Peyer's patch (i.p.p.) immunization. KLH-specific helper cells can be detected subsequently in the intraepithelial lymphocyte population and also among lamina propria lymphocytes. The helper cells also relocate to PP distant to their site of origin where they are retained only when antigen is present. While i.p.p. immunization is an efficient route for the induction of IgA helper cells in gut-associated lymphoid tissue, it differs from oral immunization in that concomitant induction of antigen-specific splenic suppressor cells does not occur, indicating a role for epithelial antigen processing in this phenomenon. PMID:2450831

  7. Predation risk is an ecological constraint for helper dispersal in a cooperatively breeding cichlid.

    PubMed Central

    Heg, Dik; Bachar, Zina; Brouwer, Lyanne; Taborsky, Michael

    2004-01-01

    Environmental conditions are thought to be responsible for the extent and benefits of cooperative breeding in many animal societies, but experimental tests are scarce. We manipulated predator pressure in the cooperatively breeding cichlid Neolamprologus pulcher in Lake Tanganyika, where predators have been suggested to influence helper and breeder survival, helper dispersal and group reproductive success. We varied the type and intensity of predation by releasing medium, large, or no predators inside large underwater cages enclosing two or three group territories. Helper and breeder survival, helper dispersal and group reproductive success decreased from the control, to the medium- and large-predator treatments. These effects were modified by helper body size and the number of adults protecting the group from predators, supporting the 'group augmentation hypothesis'. Predators forced helpers to stay closer to, and spend more time inside, protective shelters. The results demonstrate the importance of predators for group living in this species, and support the 'ecological constraints hypothesis' of cooperative breeding, in the sense that subordinates stay at home rather than leave and breed independently under the risk of predation. PMID:15556889

  8. Tbet Deficiency Causes T Helper Cell Dependent Airways Eosinophilia and Mucus Hypersecretion in Response to Rhinovirus Infection

    PubMed Central

    Glanville, Nicholas; Schröder, Armin; Walton, Ross P.; Johnston, Sebastian L.

    2016-01-01

    Current understanding of adaptive immune, particularly T cell, responses to human rhinoviruses (RV) is limited. Memory T cells are thought to be of a primarily T helper 1 type, but both T helper 1 and T helper 2 memory cells have been described, and heightened T helper 2/ lessened T helper 1 responses have been associated with increased RV-induced asthma exacerbation severity. We examined the contribution of T helper 1 cells to RV-induced airways inflammation using mice deficient in the transcription factor T-Box Expressed In T Cells (Tbet), a critical controller of T helper 1 cell differentiation. Using flow cytometry we showed that Tbet deficient mice lacked the T helper 1 response of wild type mice and instead developed mixed T helper 2/T helper 17 responses to RV infection, evidenced by increased numbers of GATA binding protein 3 (GATA-3) and RAR-related orphan receptor gamma t (RORγt), and interleukin-13 and interleukin-17A expressing CD4+ T cells in the lung. Forkhead box P3 (FOXP3) and interleukin-10 expressing T cell numbers were unaffected. Tbet deficient mice also displayed deficiencies in lung Natural Killer, Natural Killer T cell and γδT cell responses, and serum neutralising antibody responses. Tbet deficient mice exhibited pronounced airways eosinophilia and mucus production in response to RV infection that, by utilising a CD4+ cell depleting antibody, were found to be T helper cell dependent. RV induction of T helper 2 and T helper 17 responses may therefore have an important role in directly driving features of allergic airways disease such as eosinophilia and mucus hypersecretion during asthma exacerbations. PMID:27683080

  9. Model Checking to Assess T-Helper Cell Plasticity

    PubMed Central

    Abou-Jaoudé, Wassim; Monteiro, Pedro T.; Naldi, Aurélien; Grandclaudon, Maximilien; Soumelis, Vassili; Chaouiya, Claudine; Thieffry, Denis

    2015-01-01

    Computational modeling constitutes a crucial step toward the functional understanding of complex cellular networks. In particular, logical modeling has proven suitable for the dynamical analysis of large signaling and transcriptional regulatory networks. In this context, signaling input components are generally meant to convey external stimuli, or environmental cues. In response to such external signals, cells acquire specific gene expression patterns modeled in terms of attractors (e.g., stable states). The capacity for cells to alter or reprogram their differentiated states upon changes in environmental conditions is referred to as cell plasticity. In this article, we present a multivalued logical framework along with computational methods recently developed to efficiently analyze large models. We mainly focus on a symbolic model checking approach to investigate switches between attractors subsequent to changes of input conditions. As a case study, we consider the cellular network regulating the differentiation of T-helper (Th) cells, which orchestrate many physiological and pathological immune responses. To account for novel cellular subtypes, we present an extended version of a published model of Th cell differentiation. We then use symbolic model checking to analyze reachability properties between Th subtypes upon changes of environmental cues. This allows for the construction of a synthetic view of Th cell plasticity in terms of a graph connecting subtypes with arcs labeled by input conditions. Finally, we explore novel strategies enabling specific Th cell polarizing or reprograming events. PMID:25674559

  10. Transcription factor interplay in T helper cell differentiation.

    PubMed

    Evans, Catherine M; Jenner, Richard G

    2013-11-01

    The differentiation of CD4 helper T cells into specialized effector lineages has provided a powerful model for understanding immune cell differentiation. Distinct lineages have been defined by differential expression of signature cytokines and the lineage-specifying transcription factors necessary and sufficient for their production. The traditional paradigm of differentiation towards Th1 and Th2 subtypes driven by T-bet and GATA3, respectively, has been extended to incorporate additional T cell lineages and transcriptional regulators. Technological advances have expanded our view of these lineage-specifying transcription factors to the whole genome and revealed unexpected interplay between them. From these data, it is becoming clear that lineage specification is more complex and plastic than previous models might have suggested. Here, we present an overview of the different forms of transcription factor interplay that have been identified and how T cell phenotypes arise as a product of this interplay within complex regulatory networks. We also suggest experimental strategies that will provide further insight into the mechanisms that underlie T cell lineage specification and plasticity.

  11. Subpopulation of human helper and suppressor T lymphocytes

    SciTech Connect

    Venkataraman, M.; Levin, R.D.; Westerman, M.P.

    1983-07-01

    Mitogen driven differentiation of normal human mononuclear cells is a well-established model for the study of antibody synthesis in man. In certain rare individuals who are clinically normal, unfractionated mononuclear cells or a mixture of purified B plus T lymphocytes differentiate into immunoglobulin producing cells in response to purified protein derivative of tuberculin (PPD) but not in response to pokeweed mitogen (PWM). To evaluate this observation we have irradiated T cells from such individuals to eliminate naturally occurring suppressor T cell activity and then added the irradiated T cells back to autologous B cells before culture. The B cells then responded to PWM. The original PPD responses of cells from these individuals were now significantly reduced. Although, there was no difference between PWM nonresponders and responders in the number of OKT-8 positive cells, elimination of OKT-8 positive cells in the PWM nonresponders with OKT-8 monoclonal antibody and complement resulted in a significantly increased response to PWM. This study indicates that there are suppressor T cells which specifically inhibit B cell response to PWM without affecting the PPD response. These results also show that the helper T cells involved in the PWM response are radioresistant and those involved in the PPD response are radiosensitive.

  12. User manual for SPLASH (Single Panel Lamp and Shroud Helper).

    SciTech Connect

    Larsen, Marvin Elwood

    2006-02-01

    The radiant heat test facility develops test sets providing well-characterized thermal environments, often representing fires. Many of the components and procedures have become standardized to such an extent that the development of a specialized design tool to determine optimal configurations for radiant heat experiments was appropriate. SPLASH (Single Panel Lamp and Shroud Helper) is that tool. SPLASH is implemented as a user-friendly, Windows-based program that allows a designer to describe a test setup in terms of parameters such as number of lamps, power, position, and separation distance. This document is a user manual for that software. Any incidental descriptions of theory are only for the purpose of defining the model inputs. The theory for the underlying model is described in SAND2005-2947 (Ref. [1]). SPLASH provides a graphical user interface to define lamp panel and shroud designs parametrically, solves the resulting radiation enclosure problem for up to 2500 surfaces, and provides post-processing to facilitate understanding and documentation of analyzed designs.

  13. From interleukin-9 to T helper 9 cells.

    PubMed

    Stassen, Michael; Schmitt, Edgar; Bopp, Tobias

    2012-01-01

    Interleukin-9 (IL-9), cloned more than 20 years ago, was initially thought to be a Th2-specific cytokine. This assumption was initially confirmed by functional analyses showing that both IL-9 and Th2 cells play an important role in the pathogenesis of asthma, IgE class switch recombination, and resolution of parasitic infections. However, recently it was shown that IL-9-producing CD4(+) T cells represent the discrete T helper subset Th9 cells. Herein, we will review the cytokines and transcription factors known to promote the development of Th9 cells and their potential functional properties in relation to the biological activities of IL-9. In addition, we will discuss how Th9 cells are related to Th2, Th17, and T(reg) cells, as both an alternative source of IL-9 and in view of the fact that plasticity of CD4(+) T cell differentiation is currently a strong matter of debate in immunologic research.

  14. Evaluation of the T helper 17 axis in ankylosing spondylitis.

    PubMed

    Taylan, Ali; Sari, Ismail; Kozaci, Didem L; Yuksel, Arif; Bilge, Safak; Yildiz, Yasar; Sop, Gulten; Coker, Isil; Gunay, Necati; Akkoc, Nurullah

    2012-08-01

    To evaluate the T helper 17 (Th17) axis and its relation to tumor necrosis factor (TNF) alpha blockage and disease activity in ankylosing spondylitis (AS). The study included 127 AS patients (100M/27F) and 38 (27M/11F) controls. Spinal mobility was assessed by the bath ankylosing spondylitis metrology index (BASMI). Patients were also evaluated with the bath ankylosing spondylitis functional (BASFI) and bath ankylosing spondylitis disease activity index. Cytokines including IL-6, IL-12, TGF-β, IL-17A, and IL-23 were measured in serum sample using commercially available ELISA kits. Cytokines including IL-6, IL-12, TGF-β, IL-17, and IL-23 were significantly higher in the AS patients than the controls (P < 0.05). The Th-17-related cytokines were not different between patients treated with anti-TNF and conventional therapies (P > 0.05). Cytokines were also similar between patients with active and inactive disease (P > 0.05). On correlation analysis, IL-17 was correlated with IL-23 and IL-12 (P < 0.05) and IL-23 showed correlations with IL-12 and BASMI (P < 0.05). We found serum levels of Th-17-related cytokines to be significantly increased in the sera of AS patients. Disease activity and treatment type did not affect the level of these cytokines.

  15. Generation and Expansion of T Helper 17 Lymphocytes Ex Vivo.

    PubMed

    Alizadeh, Darya; Larmonier, Nicolas

    2016-01-01

    CD4(+) T helper (Th) lymphocytes are essential elements of the complex cellular networks regulating the initiation, development, and termination of adaptive immune responses. Different independent and specialized subsets of Th cells can be distinguished based on their dedicated transcription factor and cytokine expression profiles. Th17 lymphocytes have been described about a decade ago as CD4(+) Th cells producing high quantity of IL-17A as a signature cytokine. Since their initial discovery, Th17 have drawn intense scrutiny for their dominant role in the pathogenesis of multiple autoimmune, infectious diseases and allergy. The influence of Th17 lymphocytes in cancer remains however ambiguous. The plethoric functions of Th17 may rely on the remarkable plasticity of these cells, endowed with the ability to trans-differentiate into other Th subpopulations depending on the environmental cytokine context. The possibility to generate Th17 ex vivo has facilitated the elucidation of the signals and transcription factors required for their differentiation and functions and has allowed for the evaluation of their functions following adoptive transfer in vivo. Several protocols have been developed to produce Th17 in vitro. The intent of this chapter is to provide examples of procedures for generating and expanding Th17 ex vivo. PMID:26530797

  16. T helper cell activation and human retroviral pathogenesis.

    PubMed Central

    Copeland, K F; Heeney, J L

    1996-01-01

    T helper (Th) cells are of central importance in regulating many critical immune effector mechanisms. The profile of cytokines produced by Th cells correlates with the type of effector cells induced during the immune response to foreign antigen. Th1 cells induce the cell-mediated immune response, while Th2 cells drive antibody production. Th cells are the preferential targets of human retroviruses. Infections with human T-cell leukemia virus (HTLV) or human immunodeficiency virus (HIV) result in the expansion of Th cells by the action of HTLV (adult T-cell leukemia) or the progressive loss of T cells by the action of HIV (AIDS). Both retrovirus infections impart a high-level activation state in the host immune cells as well as systemically. However, diverging responses to this activation state have contrasting effects on the Th-cell population. In HIV infection, Th-cell loss has been attributed to several mechanisms, including a selective elimination of cells by apoptosis. The induction of apoptosis in HIV infection is complex, with many different pathways able to induce cell death. In contrast, infection of Th cells with HTLV-1 affords the cell a protective advantage against apoptosis. This advantage may allow the cell to escape immune surveillance, providing the opportunity for the development of Th-cell cancer. In this review, we will discuss the impact of Th-cell activation and general immune activation on human retrovirus expression with a focus upon Th-cell function and the progression to disease. PMID:8987361

  17. Evaluation of the T helper 17 axis in ankylosing spondylitis.

    PubMed

    Taylan, Ali; Sari, Ismail; Kozaci, Didem L; Yuksel, Arif; Bilge, Safak; Yildiz, Yasar; Sop, Gulten; Coker, Isil; Gunay, Necati; Akkoc, Nurullah

    2012-08-01

    To evaluate the T helper 17 (Th17) axis and its relation to tumor necrosis factor (TNF) alpha blockage and disease activity in ankylosing spondylitis (AS). The study included 127 AS patients (100M/27F) and 38 (27M/11F) controls. Spinal mobility was assessed by the bath ankylosing spondylitis metrology index (BASMI). Patients were also evaluated with the bath ankylosing spondylitis functional (BASFI) and bath ankylosing spondylitis disease activity index. Cytokines including IL-6, IL-12, TGF-β, IL-17A, and IL-23 were measured in serum sample using commercially available ELISA kits. Cytokines including IL-6, IL-12, TGF-β, IL-17, and IL-23 were significantly higher in the AS patients than the controls (P < 0.05). The Th-17-related cytokines were not different between patients treated with anti-TNF and conventional therapies (P > 0.05). Cytokines were also similar between patients with active and inactive disease (P > 0.05). On correlation analysis, IL-17 was correlated with IL-23 and IL-12 (P < 0.05) and IL-23 showed correlations with IL-12 and BASMI (P < 0.05). We found serum levels of Th-17-related cytokines to be significantly increased in the sera of AS patients. Disease activity and treatment type did not affect the level of these cytokines. PMID:21833527

  18. Helper virus is not required for in vitro erythroid transformation of hematopoietic cells by Friend virus.

    PubMed

    Hankins, W D; Krantz, S B

    1980-09-01

    The Friend polycythemia virus complex (FVP), consisting of the replication-defective spleen focus-forming virus (SFFV) and a helper Friend murine leukemia virus (MuLV-F), produces erythroleukemia within 2-3 weeks in vivo. We have recently reported in vitro transformation of bone marrow cells by FVP, producing clusters of erythroid colonies (erythroid bursts) 4-6 days after infection. In contrast to uninfected bone marrow cells, FVP-treated cells proliferated and differentiated (synthesized hemoglobin) in the absence of added erythropoietin, the physiologic regulator of erythropoiesis. The relative roles of helper murine leukemia virus (MuLV) and SFFV in the in vitro erythroid transformation have now been examined. Pseudotype studies and the finding that cloned MuLV-F (free of SFFV) did not induce burst formation indicated that SFFV was essential for this in vitro effect of FVP. Because SFFV could not be obtained free of helper MuLV, we assessed the requirement of MuLV in the transformation by kinetic analyses of helper-deficient and helper-excess FVP preparations. Whereas helper-excess FVP gave single-hit kinetics both in vivo and in vitro, the helper-deficient FVP followed multiple-hit kinetics when titrated for spleen focus formation in vivo. Addition of MuLV-F to helper-deficient FVP prior to injection resulted in a marked enhancement of spleen focus formation and a conversion from multiple-hit to single-hit kinetics. In contrast, titration of this same preparation for erythroid burst transformation in vitro yielded single-hit kinetics, and the addition of helper MuLV-F had no effect. The time course of burst development was similar with or without added MuLV-F. Unlike burst transformation, SFFV production by these infected cultures followed multiple-hit kinetics. Addition of MuLV-F at the time of infection led to an enhancement of SFFV production and conversion of the titration curve from multiple-hit to single-hit. These data are consistent with the idea that

  19. T helper 1 immunity requires complement-driven NLRP3 inflammasome activity in CD4⁺ T cells.

    PubMed

    Arbore, Giuseppina; West, Erin E; Spolski, Rosanne; Robertson, Avril A B; Klos, Andreas; Rheinheimer, Claudia; Dutow, Pavel; Woodruff, Trent M; Yu, Zu Xi; O'Neill, Luke A; Coll, Rebecca C; Sher, Alan; Leonard, Warren J; Köhl, Jörg; Monk, Pete; Cooper, Matthew A; Arno, Matthew; Afzali, Behdad; Lachmann, Helen J; Cope, Andrew P; Mayer-Barber, Katrin D; Kemper, Claudia

    2016-06-17

    The NLRP3 inflammasome controls interleukin-1β maturation in antigen-presenting cells, but a direct role for NLRP3 in human adaptive immune cells has not been described. We found that the NLRP3 inflammasome assembles in human CD4(+) T cells and initiates caspase-1-dependent interleukin-1β secretion, thereby promoting interferon-γ production and T helper 1 (T(H)1) differentiation in an autocrine fashion. NLRP3 assembly requires intracellular C5 activation and stimulation of C5a receptor 1 (C5aR1), which is negatively regulated by surface-expressed C5aR2. Aberrant NLRP3 activity in T cells affects inflammatory responses in human autoinflammatory disease and in mouse models of inflammation and infection. Our results demonstrate that NLRP3 inflammasome activity is not confined to "innate immune cells" but is an integral component of normal adaptive T(H)1 responses. PMID:27313051

  20. Newly identified helper bacteria stimulate ectomycorrhizal formation in Populus

    SciTech Connect

    Labbe, Jessy L.; Weston, David J.; Dunkirk, Nora; Pelletier, Dale A.; Tuskan, Gerald A.

    2014-10-24

    Mycorrhiza helper bacteria (MHB) are known to increase host root colonization by mycorrhizal fungi but the molecular mechanisms and potential tripartite trophic interactions are poorly understood. Through an effort to study Populus microbiome, we isolated 21 Pseudomonas strains from native Populus deltoides roots. These bacterial isolates were characterized and screened for MHB effectiveness on the Populus-Laccaria system. Two other Pseudomonas strains (i.e., Pf-5 and BBc6R8) from existing collections were also included as reference in the screening process. We analyzed Laccaria bicolor S238N growth rate, mycelial architecture and transcriptional changes induced by the contrasting Pseudomonas strains (i.e., inhibitory, neutral and beneficial). We characterized 17 out of the 21 Pseudomonas strains from the Populus rhizosphere with positive effects on L. bicolor S238N growth, as well as on Populus root architecture and colonization by L. bicolor S238N across three Populus species. Four of seven reporter genes, Tra1, Tectonin2, Gcn5 and Cipc1, thought to be specific to the interaction with strain BBc6R8, were induced or repressed while interacting with six (i.e., GM17, GM33, GM41, GM48, Pf-5 and BBc6R8) of the tested Pseudomonas strains. GM41 promoted the highest roots colonization across three Populus species but most notably in P. deltoides, which is otherwise, poorly colonized by L. bicolor. Here we report novel MHB strains isolated from native Populus that improve roots colonization. This tripartite relationship could be exploited in nursery production for target Populus species/genotypes as a means of improving establishment and survival in marginal lands.

  1. Newly identified helper bacteria stimulate ectomycorrhizal formation in Populus

    DOE PAGES

    Labbe, Jessy L.; Weston, David J.; Dunkirk, Nora; Pelletier, Dale A.; Tuskan, Gerald A.

    2014-10-24

    Mycorrhiza helper bacteria (MHB) are known to increase host root colonization by mycorrhizal fungi but the molecular mechanisms and potential tripartite trophic interactions are poorly understood. Through an effort to study Populus microbiome, we isolated 21 Pseudomonas strains from native Populus deltoides roots. These bacterial isolates were characterized and screened for MHB effectiveness on the Populus-Laccaria system. Two other Pseudomonas strains (i.e., Pf-5 and BBc6R8) from existing collections were also included as reference in the screening process. We analyzed Laccaria bicolor S238N growth rate, mycelial architecture and transcriptional changes induced by the contrasting Pseudomonas strains (i.e., inhibitory, neutral and beneficial).more » We characterized 17 out of the 21 Pseudomonas strains from the Populus rhizosphere with positive effects on L. bicolor S238N growth, as well as on Populus root architecture and colonization by L. bicolor S238N across three Populus species. Four of seven reporter genes, Tra1, Tectonin2, Gcn5 and Cipc1, thought to be specific to the interaction with strain BBc6R8, were induced or repressed while interacting with six (i.e., GM17, GM33, GM41, GM48, Pf-5 and BBc6R8) of the tested Pseudomonas strains. GM41 promoted the highest roots colonization across three Populus species but most notably in P. deltoides, which is otherwise, poorly colonized by L. bicolor. Here we report novel MHB strains isolated from native Populus that improve roots colonization. This tripartite relationship could be exploited in nursery production for target Populus species/genotypes as a means of improving establishment and survival in marginal lands.« less

  2. Generation of helper-dependent adenoviral vectors by homologous recombination.

    PubMed

    Toietta, Gabriele; Pastore, Lucio; Cerullo, Vincenzo; Finegold, Milton; Beaudet, Arthur L; Lee, Brendan

    2002-02-01

    Helper-dependent adenoviral vectors (HD-Ad) represent a potentially valuable tool for safe and prolonged gene expression in vivo. The current approach for generating these vectors is based on ligation of the expression cassette into large plasmids containing the viral inverted terminal repeats flanking "stuffer" DNA to maintain a final size above the lower limit for efficient packaging into the adenovirus capsid (approximately 28 kb). The ligation to produce the viral plasmid is generally very inefficient. Similar problems in producing first-generation adenoviral (FG-Ad) vectors were circumvented with the development of a system taking advantage of efficient homologous recombination between a shuttle plasmid containing the expression cassette and a FG-Ad vector backbone in the Escherichia coli strain BJ5183. Here we describe a method for fast and efficient generation of HD-Ad vector plasmids that can accommodate expression cassettes of any size up to 35 kb. To validate the system, we generated a HD-Ad vector expressing the fusion protein between beta-galactosidase and neomycin resistance genes under the control of the SR alpha promoter, and one expressing the enhanced green fluorescent protein under the control of the cytomegalovirus promoter. The viruses were rescued and tested in vitro and for in vivo expression in mice. The data collected indicate the possibility for achieving a high level of hepatocyte transduction using HD-Ad vectors derived from plasmids obtained by homologous recombination in E. coli, with no significant alteration of liver enzymes and a less severe, transient thrombocytopenia in comparison with previous reports with similar doses of a FG-Ad vector. PMID:11829528

  3. Newly identified helper bacteria stimulate ectomycorrhizal formation in Populus

    PubMed Central

    Labbé, Jessy L.; Weston, David J.; Dunkirk, Nora; Pelletier, Dale A.; Tuskan, Gerald A.

    2014-01-01

    Mycorrhiza helper bacteria (MHB) are known to increase host root colonization by mycorrhizal fungi but the molecular mechanisms and potential tripartite interactions are poorly understood. Through an effort to study Populus microbiome, we isolated 21 Pseudomonas strains from native Populus deltoides roots. These bacterial isolates were characterized and screened for MHB effectiveness on the Populus-Laccaria system. Two additional Pseudomonas strains (i.e., Pf-5 and BBc6R8) from existing collections were included for comparative purposes. We analyzed the effect of co-cultivation of these 23 individual Pseudomonas strains on Laccaria bicolor “S238N” growth rate, mycelial architecture and transcriptional changes. Nineteen of the 23 Pseudomonas strains tested had positive effects on L. bicolor S238N growth, as well as on mycelial architecture, with strains GM41 and GM18 having the most significant effect. Four of seven L. bicolor reporter genes, Tra1, Tectonin2, Gcn5, and Cipc1, thought to be regulated during the interaction with MHB strain BBc6R8, were induced or repressed, while interacting with Pseudomonas strains GM17, GM33, GM41, GM48, Pf-5, and BBc6R8. Strain GM41 promoted the highest roots colonization across three Populus species but most notably in P. deltoides, which is otherwise poorly colonized by L. bicolor. Here we report novel MHB strains isolated from native Populus that improve L. bicolor root colonization on Populus. This tripartite relationship could be exploited for Populus species/genotypes nursery production as a means of improving establishment and survival in marginal lands. PMID:25386184

  4. Participants' perceptions of a peer-helper, telephone-based social support intervention for melanoma patients.

    PubMed

    Rudy, R R; Rosenfeld, L B; Galassi, J P; Parker, J; Schanberg, R

    2001-01-01

    This descriptive study investigated perceptions of a peer-helper, telephone-based, social support intervention for melanoma patients receiving immunotherapy. Participants were 59 male and female Stage 3 or4 melanoma patients (helpees) at a Comprehensive Cancer Center and 29 former patients (helpers). Helpers were matched with helpees about to begin immunotherapy based on the site of the melanoma, age, and, when possible, biological sex. The intervention consisted of 2 required telephone contacts initiated by the helper before the helpee's first and second immunotherapy treatments. The reactions to this social support intervention were assessed using surveys and telephone interviews with both open- and closed-ended questions. Results indicated that (a) helpees became more sensitive and open to available social support in their environment; (b) helpers and helpees thought the intervention was effective; and (c) the telephone, as a medium for providing support, was a satisfactory substitute for face-to-face interaction. Limitations of the study and future directions for telephone-based support programs for melanoma patients are discussed.

  5. Insurance-based advantage to helpers in a tropical hover wasp.

    PubMed

    Field, J; Shreeves, G; Sumner, S; Casiraghi, M

    2000-04-20

    The origin and maintenance of eusociality is a central problem in evolutionary biology. Eusocial groups contain individuals that forfeit their own reproduction in order to help others reproduce. In facultatively eusocial taxa, offspring can choose whether to found new nests or become helpers in their natal groups. In many facultatively eusocial insects, offspring need continuous care during development, but adult carers have life expectancies shorter than the developmental period. When a lone foundress dies, her partly reared brood are usually doomed. Here, we show that helpers in a tropical hover wasp (Liostenogaster flavolineata) have an insurance-based advantage over lone foundresses because after a helper dies, most of the brood that she has partly reared will be brought to maturity by surviving nest-mates. After some of the helpers are experimentally removed from a multi-female nest, the reduced group is left with more brood than it would normally rear. We found that larger, more valuable extra brood were reared through to maturity, but not smaller, less valuable brood. Smaller brood may be sacrificed to feed larger brood, and reduced groups probably benefited from increased short-term helper recruitment. Rearing extra brood did not increase adult mortality or brood development time.

  6. Change in the number of informal helpers of frail older persons.

    PubMed Central

    Miller, B; Furner, S E

    1994-01-01

    Little is known of the extent to which helper networks of frail older persons change over time and what factors are associated with change. Few national estimates of the scope of change exist to aid policy planners. This study provides national estimates of changes in the size of the informal helping network of frail elderly by sociodemographic and functional status subgroups of this segment of the population. The data are drawn from the 1982-84 National Long Term Care Survey, which included longitudinal followup of 4,530 respondents living in the community at both times. Bivariate patterns of change over 2 years in the number of informal helpers were analyzed. Sociodemographic factors (sex, age group, and race) of the frail elderly may be more important influences on change in the number of helpers than functional status expressed in terms of their limitations in activities of daily living. PMID:8041861

  7. T-helper cell-mediated factors in drug-induced liver injury.

    PubMed

    Wang, Xinzhi; Zhang, Luyong; Jiang, Zhenzhou

    2015-07-01

    Drug-induced liver injury (DILI) leads to a large burden on the healthcare system due to its potential morbidity and mortality. The key for predicting and preventing DILI is to understand the underlying mechanisms. Hepatic inflammation is one of the most common features of DILI. The inflammation can be attributed to the innate immune response. The adaptive immune system is also affected by the innate immune response resulting in liver damage. T-helper cells are important regulators of acquired immunity. T-helper cell-mediated immune responses play pivotal roles in the pathogenesis of a variety of liver disorders. This review summarizes recent advances in the T-helper cell-mediated factors in DILI and potential mechanisms, which may lead to a better understanding of DILI. PMID:25752261

  8. Mucosal Regulatory T Cells and T Helper 17 Cells in HIV-Associated Immune Activation

    PubMed Central

    Pandiyan, Pushpa; Younes, Souheil-Antoine; Ribeiro, Susan Pereira; Talla, Aarthi; McDonald, David; Bhaskaran, Natarajan; Levine, Alan D.; Weinberg, Aaron; Sekaly, Rafick P.

    2016-01-01

    Residual mucosal inflammation along with chronic systemic immune activation is an important feature in individuals infected with human immunodeficiency virus (HIV), and has been linked to a wide range of co-morbidities, including malignancy, opportunistic infections, immunopathology, and cardiovascular complications. Although combined antiretroviral therapy (cART) can reduce plasma viral loads to undetectable levels, reservoirs of virus persist, and increased mortality is associated with immune dysbiosis in mucosal lymphoid tissues. Immune-based therapies are pursued with the goal of improving CD4+ T-cell restoration, as well as reducing chronic immune activation in cART-treated patients. However, the majority of research on immune activation has been derived from analysis of circulating T cells. How immune cell alterations in mucosal tissues contribute to HIV immune dysregulation and the associated risk of non-infectious chronic complications is less studied. Given the significant differences between mucosal T cells and circulating T cells, and the immediate interactions of mucosal T cells with the microbiome, more attention should be devoted to mucosal immune cells and their contribution to systemic immune activation in HIV-infected individuals. Here, we will focus on mucosal immune cells with a specific emphasis on CD4+ T lymphocytes, such as T helper 17 cells and CD4+Foxp3+ regulatory T cells (Tregs), which play crucial roles in maintaining mucosal barrier integrity and preventing inflammation, respectively. We hypothesize that pro-inflammatory milieu in cART-treated patients with immune activation significantly contributes to enhanced loss of Th17 cells and increased frequency of dysregulated Tregs in the mucosa, which in turn may exacerbate immune dysfunction in HIV-infected patients. We also present initial evidence to support this hypothesis. A better comprehension of how pro-inflammatory milieu impacts these two types of cells in the mucosa will shed light

  9. Opposite effects of interleukin-4 on memory T helper cell development depend on interleukin-2.

    PubMed

    Bemer, V; Motta, I; Perret, R; Truffa-Bachi, P

    1996-01-01

    We previously reported that cyclosporin A (CSA) promotes the generation of T helper memory cells during antigenic priming of murine spleen cells in vitro. More recently, we have demonstrated that interleukin-2 (IL2) has a downmodulating effect on T helper memory cell generation. The present data address the role of the other T cell growth factor, IL4, upon induction of these cells. The data presented here show that IL4 can interfere with this process: addition of rIL4 to immunosuppressed priming cultures leads to a considerable decrease in the helper activity of the recovered cells. However, in standard cultures, in which IL2 is normally produced, no effect of IL4 on T helper memory cell generation was found. Addition of IL4 has important consequences for cytokines produced upon antigenic restimulation. In standard cultures, IL4 primes for cells expressing high levels of IL2 and IL4 mRNA. Strikingly, in immunosuppressed priming cultures, IL4 counterbalances the CSA-induced blockade of the IFN gamma gene. Taken together, our results suggest that the unique role of IL4 is to drive T helper memory precursors into an IL4 production differentiation pathway. However, IL4 has a downmodulating effect on memory T helper cell induction when IL2 is not produced. These results confirm that synergy between IL2 and IL4 is mandatory for the directive role of IL4 upon IL4-producing cells. Furthermore, the finding that IL4 promotes the induction of IFN gamma in a CSA-resistant pathway represents a new tool for analysis of regulation of the IFN gamma gene.

  10. Associations of Warmth and Control of Filipina Domestic Helpers and Mothers to Hong Kong Kindergarten Children's Social Competence

    ERIC Educational Resources Information Center

    Ip, Hoi Man; Cheung, Sum Kwing; McBride-Chang, Catherine; Chang, Lei

    2008-01-01

    Research Findings: Across 63 Hong Kong families, both Filipina domestic helpers and mothers separately rated their own caregiving style (warmth and control) and kindergarten children's social competence. Results indicated that Filipina helpers rated themselves as higher in warmth than mothers did. In addition, self-rated warmth of both caregivers,…

  11. English and Federal Government. Federal Textbook on Citizenship--Home Study Course. Section 2, for the Helper.

    ERIC Educational Resources Information Center

    Immigration and Naturalization Service (Dept. of Justice), Washington, DC.

    Course arrangement, specific helper instructions, and terminology are covered in this helper's handbook for home study candidates for naturalization who speak English to learn to read and write English. It is intended to be used to give a limited amount of help provided by a family member or neighbor, and accompanies the booklet "English and…

  12. Reproductive success depends on the quality of helpers in the endangered, cooperative El Oro parakeet (Pyrrhura orcesi).

    PubMed

    Klauke, Nadine; Segelbacher, Gernot; Schaefer, H M

    2013-04-01

    In cooperative species, helping behaviour and reproductive success can be correlated, but understanding this correlation is often impaired by the difficulty to correctly infer causation. While helpers can incur costs by participating in brood care, it is yet unclear if their help depends on their individual quality. We address these questions in the previously unknown cooperative breeding system of the endangered El Oro parakeet (Pyrrhura orcesi). Specifically, we ask (i) whether breeders benefit directly from helpers by an enhanced reproductive success and if so, (ii) whether the amount of this potential benefit is regulated by the quality of contributing group members. Groups consist of a dominant breeding pair accompanied by helpers, but cooperation is not obligate. Microsatellite heterozygosity was used to assess individual quality; its suitability as indicator of quality was reflected in the positive relationship between offspring heterozygosity and recruitment into the population. The reproductive success of breeding pairs depended on helper (genetic) quality and the number of helpers. This relationship occurred on two different levels: clutch size and fledging success, indicating (i) that females profit from high-quality helpers and probably adjust clutch size accordingly and (ii) that the helpers increase fledging success. Congruently, we found that offspring body condition is positively affected by helper quality, which is most probably explained by the increased feeding rates when helpers are present. We suggest a causal link between cooperation and reproductive success in this frugivorous, endangered parakeet. Further, helper (genetic) quality can be a relevant factor for determining reproductive fitness in cooperative species, particularly in small and bottlenecked populations.

  13. Exploring the role of Natural Helpers in efforts to address disparities for children with conduct problems

    PubMed Central

    Acevedo-Polakovich, I. David; Niec, Larissa N.; Barnett, Miya L.; Bell, Katrina M.; Aguilar, Gerardo; Vilca, Jeanette; Abbenante-Honold, Emily S.; Christian, Allison S.; Peer, Samuel O.

    2014-01-01

    The incorporation of natural helpers into services has been suggested as an innovative strategy to address disparities for historically underserved children with conduct problems. In order to inform incorporation efforts, this study examined the perceptions of natural helpers serving one U.S. Latina/o community regarding need for services for children with conduct problems, their reactions to a specific parent training intervention, and the training and support needed to deliver this intervention successfully. Participants identified a need for culturally-responsive services for children with conduct problems, and felt that parent training would be appropriate for the families they serve. Participants further identified specific training and support that they would require in order to deliver parent training with fidelity and effectiveness. Findings support the suggestion that natural helpers have the potential to address service disparities among Latina/o children with conduct problems. Recommendations from natural helpers should guide the development of culturally-adapted preventive interventions that help address existing service disparities. PMID:24910488

  14. CIB1 and CIB2 are HIV-1 helper factors involved in viral entry.

    PubMed

    Godinho-Santos, Ana; Hance, Allan J; Gonçalves, João; Mammano, Fabrizio

    2016-01-01

    HIV-1 relies on the host-cell machinery to accomplish its replication cycle, and characterization of these helper factors contributes to a better understanding of HIV-host interactions and can identify potential novel antiviral targets. Here we explored the contribution of CIB2, previously identified by RNAi screening as a potential helper factor, and its homolog, CIB1. Knockdown of either CIB1 or CIB2 strongly impaired viral replication in Jurkat cells and in primary CD4+ T-lymphocytes, identifying these proteins as non-redundant helper factors. Knockdown of CIB1 and CIB2 impaired envelope-mediated viral entry for both for X4- and R5-tropic HIV-1, and both cell-free and cell-associated entry pathways were affected. In contrast, the level of CIB1 and CIB2 expression did not influence cell viability, cell proliferation, receptor-independent viral binding to the cell surface, or later steps in the viral replication cycle. CIB1 and CIB2 knockdown was found to reduce the expression of surface molecules implicated in HIV-1 infection, including CXCR4, CCR5 and integrin α4β7, suggesting at least one mechanism through which these proteins promote viral infection. Thus, this study identifies CIB1 and CIB2 as host helper factors for HIV-1 replication that are required for optimal receptor-mediated viral entry. PMID:27489023

  15. Beyond the Reach of Ethics and Equity? Depersonalisation and Dehumanisation in Foreign Domestic Helper Narratives

    ERIC Educational Resources Information Center

    Ladegaard, Hans J.

    2013-01-01

    This paper analyses narratives told by foreign domestic helpers (FDHs) in a Hong Kong church shelter. The narratives provide evidence that FDHs appear to be untouched by the ethics and equity of Hong Kong society. They are denied the rights that apply to other groups: the right to eat, rest and talk; they are humiliated and denigrated, and the…

  16. Cook's Helper. DOT No. 317.687-010. Restaurant Occupations. Coordinator's Guide. First Edition.

    ERIC Educational Resources Information Center

    Hohhertz, Durwin

    This coordinator's guide for a module on cook's helpers, one of seven individualized units about restaurant occupations, has been developed for students enrolled in cooperative part-time training and employed in a commercial restaurant. Included in the first part of the guide are a progress chart, suggested teaching procedures, answers to the…

  17. Baker's Helper. DOT No. 313.684-010. Cafeteria Occupations. Coordinator's Guide. First Edition.

    ERIC Educational Resources Information Center

    East Texas State Univ., Commerce. Occupational Curriculum Lab.

    This study guide is one of eight individualized units developed for students enrolled in cooperative part-time training and employed in a cafeteria. Each self-paced unit is composed of information about one specific occupation; this unit focuses on the duties of the baker's helper. Materials provided in this guide for coordinator use include a…

  18. Cook's Helper. DOT No. 317.687-010. Cafeteria Occupations. Coordinator's Guide. First Edition.

    ERIC Educational Resources Information Center

    East Texas State Univ., Commerce. Occupational Curriculum Lab.

    This study guide, one of eight individualized units developed for students enrolled in cooperative part-time training and employed in a cafeteria, is composed of information about one specific occupation; this unit focuses on the duties of the cook's helper. Materials provided in this guide for coordinator use include a student progress chart; a…

  19. Sex, Attribution, and Severity Influence Intervention Decisions of Informal Helpers in Domestic Violence

    ERIC Educational Resources Information Center

    Chabot, Heather Frasier; Tracy, Tracy L.; Manning, Christine A.; Poisson, Chelsea A.

    2009-01-01

    Most domestic violence (DV) researchers examine professional intervention (e.g., police and nurses), but informal helpers (e.g., friends and bystanders) are critical. The authors measure undergraduates' intervention likelihood, type of involvement (i.e., contact with abuser), and the influence of attribution decisions in DV situations where the…

  20. Prevalence and Duties of Collegiate Human Sexuality Peer Helpers: Results of a National Study

    ERIC Educational Resources Information Center

    Butler, Scott M.; Black, David R.

    2011-01-01

    The purpose of the present study is to assess human sexuality peer helper use among college student health centers nationwide. Results from 358 institutions indicate that 53.9% of centers use peers for educational programming, prevention efforts, and/or counseling initiatives. When adjusting for institutions that sponsor a program (n = 193), the M…

  1. 29 CFR 570.52 - Occupations of motor-vehicle driver and outside helper (Order 2).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Occupations of motor-vehicle driver and outside helper (Order 2). 570.52 Section 570.52 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND STATEMENTS OF INTERPRETATION...

  2. 29 CFR 570.52 - Occupations of motor-vehicle driver and outside helper (Order 2).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Occupations of motor-vehicle driver and outside helper (Order 2). 570.52 Section 570.52 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND STATEMENTS OF INTERPRETATION...

  3. 29 CFR 570.52 - Occupations of motor-vehicle driver and outside helper (Order 2).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Occupations of motor-vehicle driver and outside helper (Order 2). 570.52 Section 570.52 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND STATEMENTS OF INTERPRETATION...

  4. 29 CFR 570.52 - Occupations of motor-vehicle driver and outside helper (Order 2).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Occupations of motor-vehicle driver and outside helper (Order 2). 570.52 Section 570.52 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND STATEMENTS OF INTERPRETATION...

  5. 29 CFR 570.52 - Occupations of motor-vehicle driver and outside helper (Order 2).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Occupations of motor-vehicle driver and outside helper (Order 2). 570.52 Section 570.52 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR REGULATIONS CHILD LABOR REGULATIONS, ORDERS AND STATEMENTS OF INTERPRETATION...

  6. CD4 T-helper cell cytokine phenotypes and antibody response following tetanus toxoid booster immunization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Routine methods for enumerating antigen-specific T-helper cells may not identify low-frequency phenotypes such as Th2 cells. We compared methods of evaluating such responses to identify tetanus toxoid- (TT) specific Th1, Th2, Th17 and IL10+ cells. Eight healthy subjects were given a TT booster vacci...

  7. CIB1 and CIB2 are HIV-1 helper factors involved in viral entry

    PubMed Central

    Godinho-Santos, Ana; Hance, Allan J.; Gonçalves, João; Mammano, Fabrizio

    2016-01-01

    HIV-1 relies on the host-cell machinery to accomplish its replication cycle, and characterization of these helper factors contributes to a better understanding of HIV-host interactions and can identify potential novel antiviral targets. Here we explored the contribution of CIB2, previously identified by RNAi screening as a potential helper factor, and its homolog, CIB1. Knockdown of either CIB1 or CIB2 strongly impaired viral replication in Jurkat cells and in primary CD4+ T-lymphocytes, identifying these proteins as non-redundant helper factors. Knockdown of CIB1 and CIB2 impaired envelope-mediated viral entry for both for X4- and R5-tropic HIV-1, and both cell-free and cell-associated entry pathways were affected. In contrast, the level of CIB1 and CIB2 expression did not influence cell viability, cell proliferation, receptor-independent viral binding to the cell surface, or later steps in the viral replication cycle. CIB1 and CIB2 knockdown was found to reduce the expression of surface molecules implicated in HIV-1 infection, including CXCR4, CCR5 and integrin α4β7, suggesting at least one mechanism through which these proteins promote viral infection. Thus, this study identifies CIB1 and CIB2 as host helper factors for HIV-1 replication that are required for optimal receptor-mediated viral entry. PMID:27489023

  8. A web-based care-requiring client and Home Helper mutual support system.

    PubMed

    Ogawa, Hidekuni; Yonezawa, Yoshiharu; Maki, Hiromichi; Hahn, Allen W; Caldwell, W Morton

    2005-01-01

    For the improved efficiency of home care of the elderly, a web-based system has been developed to enable faster communications between care-requiring clients, their Home Helper and the care manager. Changes to care items, such as cooking, bathing, washing, cleaning and shopping are usually requested by the elderly client over the telephone. However, the care central office often requires 24 hours to process and respond to such spoken requests. The system we have developed consists of Internet client computers with liquid crystal input tablets, wireless Internet Java enabled mobile phones and a central office server that yields almost instant communication. The care clients enter requests on the liquid crystal tablet at their home and then their computer sends these requests to the server at the Home Helper central office. The server automatically creates a new file of the requested items, and then immediately transfers them to the care manager and Home Helper's mobile phone. With this non-vocal and paperless system, the care-requiring clients, who can easily operate the liquid crystal tablet, can very quickly communicate their needed care change requests to their Home Helper.

  9. Suppressor of cytokine signaling 3 regulates proliferation and activation of T-helper cells.

    PubMed

    Yu, Cheng-Rong; Mahdi, Rashid M; Ebong, Samuel; Vistica, Barbara P; Gery, Igal; Egwuagu, Charles E

    2003-08-01

    Suppressors of cytokine signaling (SOCS) have been implicated in regulation of T-cell activation and cytokine-mediated differentiation of T-helper cells. In this study we have characterized the pattern of SOCS expression in naïve and activated primary T-helper cells, examined whether expression of SOCS genes is regulated by cytokine or T-cell receptor signaling, and analyzed the function of SOCS in differentiated T-cells. We show that SOCS1, SOCS2, SOCS3, CIS (cytokine-induced SH2 protein) genes are constitutively expressed in naïve T-helper cells, with SOCS3 being the most abundant. Antigen stimulation of naïve T-helper cells down-regulates SOCS3 expression and concomitantly up-regulates SOCS1, SOCS2, and CIS gene transcription, suggesting that SOCS genes are regulated differentially by T-cell activation. Down-regulation of SOCS3 expression is subsequently followed by gradual increase in SOCS3 level and corresponding decline in interleukin 2 (IL-2) secretion. In fact, SOCS3 mRNA levels are inversely correlated with the amount of IL-2 secretion and proliferative responses of differentiating T-helper cells, suggesting mutually antagonistic effects of SOCS3 and IL-2 and feedback regulation of T-cell activation by SOCS3. Furthermore, the degree of SOCS3 inhibition is antigen concentration-dependent and is mediated in part by growth factor independence-1, a T-cell transcription factor that regulates S-phase entry in T-cells. Forced overexpression of SOCS3 inhibits proliferation of T-helper cells, whereas depletion of endogenous SOCS3 by antisense SOCS3 cDNA enhances T-cell receptor- and cytokine-induced proliferation. Taken together, these results suggest a role for SOCS3 in maintaining T-helper cells in a quiescent state. Transient inhibition of SOCS3 by antigen stimulation may therefore be essential in allowing activation of resting T-cells.

  10. Dual-Specificity Phosphatase 4 Regulates STAT5 Protein Stability and Helper T Cell Polarization*

    PubMed Central

    Liao, Fang-Hsuean; Chan, Yi-Chiao; Huang, Ching-Yu

    2015-01-01

    Immune responses are critically regulated by the functions of CD4 helper T cells. Based on their secreted cytokines, helper T cells are further categorized into different subsets like Treg or Th17 cells, which suppress or promote inflammatory responses, respectively. Signals from IL-2 activate the transcription factor STAT5 to promote Treg but suppress Th17 cell differentiation. Our previous results found that the deficiency of a dual-specificity phosphatase, DUSP4, induced STAT5 hyper-activation, enhanced IL-2 signaling, and increased T cell proliferation. In this report, we examined the effects of DUSP4 deficiency on helper T cell differentiation and STAT5 regulation. Our in vivo data showed that DUSP4 mice were more resistant to the induction of autoimmune encephalitis, while in vitro differentiations revealed enhanced iTreg and reduced Th17 polarization in DUSP4-deficient T cells. To study the cause of this altered helper T cell polarization, we performed luciferase reporter assays and confirmed that, as predicted by our previous report, DUSP4 over-expression suppressed the transcription factor activity of STAT5. Surprisingly, we also found that DUSP4-deficient T but not B cells exhibited elevated STAT5 protein levels, and over-expressed DUSP4 destabilized STAT5 in vitro; moreover, this destabilization required the phosphatase activity of DUSP4, and was insensitive to MG132 treatment. Finally, domain-mapping results showed that both the substrate-interacting and the phosphatase domains of DUSP4 were required for its optimal interaction with STAT5, while the coiled-coil domain of STAT5 appeared to hinder this interaction. Our data thus provide the first genetic evidence that DUSP4 is important for helper T cell development. In addition, they also help uncover the novel, DUSP4-mediated regulation of STAT5 protein stability. PMID:26710253

  11. Helpers Program: A Pilot Test of Brief Tobacco Intervention Training in Three Corporations

    PubMed Central

    Muramoto, Myra L.; Wassum, Ken; Connolly, Tim; Matthews, Eva; Floden, Lysbeth

    2014-01-01

    Background Quitlines and worksite-sponsored cessation programs are effective and highly accessible, but limited by low utilization. Efforts to encourage use of cessation aids have focused almost exclusively on the smoker, overlooking the potential for friends, family, coworkers and others in a tobacco user’s social network to influence quitting and use of effective treatment. Methods Longitudinal, observational pilot feasibility study with six-week follow-up survey. Setting/Participants Employees of three national corporations, with a combined target audience of 102,100 employees. Intervention The Helpers Program offers Web-based brief intervention (BI) training to activate social networks of tobacco users to encourage quitting and use of effective treatment. Helpers was offered from 1/10/08 to 3/31/08, as a treatment engagement strategy, together with Free and Clear’s (F&C) telephone/Web-based cessation services. Main outcome measures web-site utilization, training completion, post-training changes in knowledge and self-efficacy with delivery of BIs, referrals to F&C, and use of BI training. Results There were 19,109 unique visitors to the Helpers Web-site. Of these, 4727 created user accounts; 1427 registered for Helpers Training; 766 completed training. There were 445 visits to the referral page and 201 e-mail or letter referrals generated. There were 67 requests for technical support. Of follow-up survey respondents (n=289), 78.9% reported offering a BI. Conclusions Offering the Helpers Program Web-site to a large, diverse audience as part of an employer-sponsored worksite health promotion program is both feasible and well accepted by employees. Website users will participate in training, encourage quitting, and refer smokers to quitline services. PMID:20176303

  12. The role of a human antigen specific T8+ cell subset in antigen presentation, helper function and contrasuppression.

    PubMed Central

    Lehner, T; Avery, J; Jones, T

    1985-01-01

    Regulation of the human immune response was studied by sequential separation of subsets of T cells, followed by assessment of their helper and suppressor functions in a series of reconstitution experiments. T8+ lymphocytes were separated by panning on streptococcal antigen (SA) coated plates into T8+ SA-adherent cells (T8+SA+) and T8+ SA-non-adherent cells (T8+SA-). The helper and suppressor functions of the T8+SA+ and T8+SA- cells, reconstituted with T4+ helper cells were then studied by a direct antibody forming cell assay. T4+ cells will not induce helper activity by 1000 ng SA alone but require the accessory function of monocytes (Mo). However, replacing Mo by T8+SA+ cells will elicit a similar helper activity by T4+ cells and SA as that induced by Mo. In addition to the antigen-specific presentation and induction of helper activity, the T8+SA+ subset displays the properties of antigen-specific contrasuppressor cells. Thus, reconstitution of T4+ cells and T8+SA- (suppressor cells) with T8+SA+ and 1000 ng SA induces helper and no suppressor activity. Substitution of Mo for the T8+SA+ cells converts the helper to a predominantly suppressor-cell function. T8+SA- cells elicit suppression with 1 ng SA in the absence of accessory cells and reconstitution with Mo, T8+SA+ or T4+ cells failed to affect the suppressor activity. Total reconstitution of the four principle subsets of T4+, T8+SA+, T8+SA- cells and Mo elicited similar antigen dose-dependent responses as those of the unseparated mononuclear cells. It seems that all four cell subsets are required for optimal immunoregulation. We suggest that the T8+SA+ can present antigen to T4+ helper cells and induce helper activity, but in addition these cells can prevent the suppressor subset of T8+ cells from inhibiting T4+ helper cells and function as contrasuppressor cells. The mechanism of these functions is not known but HLA class II antigens might play an essential role in antigen binding, presentation and

  13. How helpers help: disentangling ecological confounds from the benefits of cooperative breeding.

    PubMed

    Wright, Jonathan; Russell, Andrew F

    2008-05-01

    Evolutionary explanations for helping in cooperative breeding systems usually require a positive effect of helping on the fitness of the breeders being assisted. However, such helper effects have proven surprisingly difficult to quantify. Cockburn et al. (this issue) apply detailed statistical analyses to long-term field data on the enigmatic superb fairy-wren. They show that it is possible to disentangle the complex web of ecological and evolutionary interactions that confound so many studies. Whilst fairy-wren helpers may not increase nest productivity, they do increase future survival of breeding females. This study points the way for future statistical explorations of long-term data in other cooperative birds and mammals.

  14. Asymmetric 1-alkyl-2-acyl phosphatidylcholine: a helper lipid for enhanced non-viral gene delivery.

    PubMed

    Huang, Zhaohua; Li, Weijun; Szoka, Francis C

    2012-05-01

    Rationally designed asymmetrical alkylacyl phosphatidylcholines (APC) have been synthesized and evaluated as helper lipids for non-viral gene delivery. A long aliphatic chain (C22-C24) was introduced at the 1-position of glycerol backbone, a branched lipid chain (C18) at the 2-position, and a phosphocholine head group at the 3-position. The fusogenicity of APC depends on the length and degree of saturation of the alkyl chain. Cationic lipids were formulated with APC as either lipoplexes or nanolipoparticles, and evaluated for their stability, transfection efficiency, and cytotoxicity. APC mediated high in vitro transfection efficiency, and had low cytotoxicity. Small nanolipoparticles (less than 100 nm) can be obtained with APC by applying as low as 0.1% PEG-lipid. Our study extends the type of helper lipids that are suitable for gene transfer and points the way to improve non-viral nucleic acid delivery system other than the traditional cationic lipids optimization.

  15. T-helper cell intrinsic defects in lupus that break peripheral tolerance to nuclear autoantigens.

    PubMed

    Datta, Syamal K; Zhang, Li; Xu, Luting

    2005-04-01

    Special populations of T helper cells drive B cells to produce IgG class switched, pathogenic autoantibodies in lupus. The major source of antigenic determinants (epitopes) that trigger interactions between lupus T and B cells is nucleosomes of apoptotic cells. These epitopes can be used for antigen-specific therapy of lupus. Secondly, the autoimmune T cells of lupus are sustained because they resist anergy and activation-induced programmed cell death by markedly upregulating cyclooxygenase (COX) 2 along with the antiapoptotic molecule c-FLIP. Only certain COX-2 inhibitors block pathogenic anti-DNA autoantibody production in lupus by causing death of autoimmune T helper cells. Hence COX-2 inhibitors may work independently of their ability to block the enzymatic function of COX-2, and structural peculiarities of these select inhibitors may lead to better drug discovery and design.

  16. The use of a "token helper" in the management of classroom behavior problems and in teacher training.

    PubMed

    Ringer, V M

    1973-01-01

    A grade-four class teacher was trained in the use of token and verbal reinforcement by an experienced "token helper", who demonstrated the procedures in the classroom. The introduction of a simple token system resulted in significant decreases in the disruptive behavior of 10 pupils in two morning periods. When the token helper withdrew from the classroom, the teacher managed the token system and maintained disruptive behavior at lower than baseline levels. PMID:16795451

  17. The name of the helper: a new look at "Rumpelstiltskin".

    PubMed

    Rosegrant, John

    2008-04-01

    The fairy tale of Rumpelstiltskin is studied in conjunction with related tales to provide a fuller understanding of its meaning than previous studies have done. The content of these tales depicts ambivalence about childhood magic and ambivalence about adult reality, which are uneasily resolved by eliminating magic and dwelling in a disenchanted world. Enchantment is retained formally in the telling of the story. To the extent that transference is enchantment, similar conflicts occur during psychoanalysis: is the patient better off adhering to transference or relinquishing it--or can it be integrated with day-to-day experience?

  18. Human T Follicular Helper Cells in Primary Immunodeficiency: Quality Just as Important as Quantity.

    PubMed

    Ma, Cindy S

    2016-05-01

    T follicular helper (Tfh) cells are a subset of effector CD4(+) T cells specialised to induce Ab production by B cells. This review highlights some of the recent advances in the field of human Tfh cells that have come from the study of primary immunodeficiencies. In particular it is increasingly evident that the quality of the Tfh cells that are generated, is just as important as the quantity.

  19. Group-size-dependent punishment of idle subordinates in a cooperative breeder where helpers pay to stay

    PubMed Central

    Fischer, Stefan; Zöttl, Markus; Groenewoud, Frank; Taborsky, Barbara

    2014-01-01

    In cooperative breeding systems, dominant breeders sometimes tolerate unrelated individuals even if they inflict costs on the dominants. According to the ‘pay-to-stay’ hypothesis, (i) subordinates can outweigh these costs by providing help and (ii) dominants should be able to enforce help by punishing subordinates that provide insufficient help. This requires that dominants can monitor helping and can recognize group members individually. In a field experiment, we tested whether cooperatively breeding cichlid Neolamprologus pulcher subordinates increase their help after a forced ‘idle’ period, how other group members respond to a previously idle helper, and how helper behaviour and group responses depend on group size. Previously, idle helpers increased their submissiveness and received more aggression than control helpers, suggesting that punishment occurred to enforce help. Subordinates in small groups increased their help more than those in large groups, despite receiving less aggression. When subordinates were temporarily removed, dominants in small groups were more likely to evict returning subordinates. Our results suggest that only in small groups do helpers face a latent threat of punishment by breeders as predicted by the pay-to-stay hypothesis. In large groups, cognitive constraints may prevent breeders from tracking the behaviour of a large number of helpers. PMID:24990673

  20. Group-size-dependent punishment of idle subordinates in a cooperative breeder where helpers pay to stay.

    PubMed

    Fischer, Stefan; Zöttl, Markus; Groenewoud, Frank; Taborsky, Barbara

    2014-08-22

    In cooperative breeding systems, dominant breeders sometimes tolerate unrelated individuals even if they inflict costs on the dominants. According to the 'pay-to-stay' hypothesis, (i) subordinates can outweigh these costs by providing help and (ii) dominants should be able to enforce help by punishing subordinates that provide insufficient help. This requires that dominants can monitor helping and can recognize group members individually. In a field experiment, we tested whether cooperatively breeding cichlid Neolamprologus pulcher subordinates increase their help after a forced 'idle' period, how other group members respond to a previously idle helper, and how helper behaviour and group responses depend on group size. Previously, idle helpers increased their submissiveness and received more aggression than control helpers, suggesting that punishment occurred to enforce help. Subordinates in small groups increased their help more than those in large groups, despite receiving less aggression. When subordinates were temporarily removed, dominants in small groups were more likely to evict returning subordinates. Our results suggest that only in small groups do helpers face a latent threat of punishment by breeders as predicted by the pay-to-stay hypothesis. In large groups, cognitive constraints may prevent breeders from tracking the behaviour of a large number of helpers.

  1. Feedback mechanisms between T helper cells and macrophages in the determination of the immune response.

    PubMed

    Bar-Or, R L

    2000-01-01

    The interactions between macrophages and T helper (Th) cells are a complex interplay of positive and negative signals. Some of the mathematical models of interactions between T helpers have indeed taken the influence of macrophages into account. In this work the macrophage is not considered as an extrinsic agent, that is duly directed by the T cells to be cytotoxic, nor is there consideration of T helper cell populations that are dominantly regulated by extrinsic properties of antigens per se, or by certain classes of presenting cells that preferentially select certain classes of lymphocytes or bias their commitment. Rather, a simplified model of feedback loops between Th cells and macrophages is formulated and analyzed. It is suggested how the mutual influence between Th and macrophages can determine the cytokine secretion pattern of these populations. The model provides a feedback scenario to account for experimental findings concerning reversal in the dominance of a specific cytokine profile in the course of some infections. A possible scenario accounting for the difference between the stability of Th1 and Th2 cytokine pattern is put forward. The model suggests explanations for the variability in the outcome of the immune response according to different body compartments. A rationale is presented that accounts for paradoxical findings indicating that Th1 cytokines are sometimes responsible for the downregulation of a Th1 dominated response. PMID:10652844

  2. Comparison of Replication-Competent, First Generation, and Helper-Dependent Adenoviral Vaccines

    PubMed Central

    Weaver, Eric A.; Nehete, Pramod N.; Buchl, Stephanie S.; Senac, Julien S.; Palmer, Donna; Ng, Philip; Sastry, K. Jagannadha; Barry, Michael A.

    2009-01-01

    All studies using human serotype 5 Adenovirus (Ad) vectors must address two major obstacles: safety and the presence of pre-existing neutralizing antibodies. Helper-Dependent (HD) Ads have been proposed as alternative vectors for gene therapy and vaccine development because they have an improved safety profile. To evaluate the potential of HD-Ad vaccines, we compared replication-competent (RC), first-generation (FG) and HD vectors for their ability to induce immune responses in mice. We show that RC-Ad5 and HD-Ad5 vectors generate stronger immune responses than FG-Ad5 vectors. HD-Ad5 vectors gave lower side effects than RC or FG-Ad, producing lower levels of tissue damage and anti-Ad T cell responses. Also, HD vectors have the benefit of being packaged by all subgroup C serotype helper viruses. We found that HD serotypes 1, 2, 5, and 6 induce anti-HIV responses equivalently. By using these HD serotypes in heterologous succession we showed that HD vectors can be used to significantly boost anti-HIV immune responses in mice and in FG-Ad5-immune macaques. Since HD vectors have been show to have an increased safety profile, do not possess any Ad genes, can be packaged by multiple serotype helper viruses, and elicit strong anti-HIV immune responses, they warrant further investigation as alternatives to FG vectors as gene-based vaccines. PMID:19333387

  3. ITAM signaling in dendritic cells controls T helper cell priming by regulating MHC class II recycling

    PubMed Central

    Graham, Daniel B.; Akilesh, Holly M.; Gmyrek, Grzegorz B.; Piccio, Laura; Gilfillan, Susan; Sim, Julia; Belizaire, Roger; Carrero, Javier A.; Wang, Yinan; Blaufuss, Gregory S.; Sandoval, Gabriel; Fujikawa, Keiko; Cross, Anne H.; Russell, John H.; Cella, Marina

    2010-01-01

    Immature dendritic cells (DCs) specialize in antigen capture and maintain a highly dynamic pool of intracellular major histocompatibility complex class II (MHCII) that continuously recycles from peptide loading compartments to the plasma membrane and back again. This process facilitates sampling of environmental antigens for presentation to T helper cells. Here, we show that a signaling pathway mediated by the DC immunoreceptor tyrosine-based activation motif (ITAM)–containing adaptors (DAP12 and FcRγ) and Vav family guanine nucleotide exchange factors controls the half-life of surface peptide-MHCII (pMHCII) complexes and is critical for CD4 T-cell triggering in vitro. Strikingly, mice with disrupted DC ITAMs show defective T helper cell priming in vivo and are protected from experimental autoimmune encephalitis. Mechanistically, we show that deficiency in ITAM signaling results in increased pMHCII internalization, impaired recycling, and an accumulation of ubiquitinated MHCII species that are prematurely degraded in lysosomes. We propose a novel mechanism for control of T helper cell priming. PMID:20634378

  4. Elevated prolactin levels immediately precede decisions to babysit by male meerkat helpers.

    PubMed

    Carlson, Anne A; Russell, Andrew F; Young, Andrew J; Jordan, Neil R; McNeilly, Alan S; Parlow, Al F; Clutton-Brock, Tim

    2006-06-01

    Recent studies suggest that decisions to care for the offspring of others in societies of cooperative vertebrates may have a hormonal basis. The crucial question of whether changes in hormone levels immediately precede or merely follow bouts of offspring care, however, remains largely unanswered. Here, we show that in wild groups of cooperatively breeding meerkats, male helpers that decided to babysit for the day had significantly higher levels of prolactin, coupled with lower levels of cortisol, before initiating a babysitting session compared with similarly aged individuals that decided to forage. In addition, these hormonal differences disappeared over the course of the day, suggesting that hormone levels changed in a fundamentally different way in meerkats that babysat versus those that foraged. In contrast, long-term contributions to babysitting were not significantly associated with plasma levels of prolactin, cortisol, or testosterone in individual male helpers. Our results show, for the first time, that elevated levels of prolactin may immediately precede bouts of helping behavior but differ from recent findings on the same study population in which plasma levels of cortisol, but not prolactin, were significantly and positively associated with rates of pup feeding by male helpers. Together, these results lend significant weight to the idea that decisions to help in cooperative vertebrates have a hormonal basis, although different hormones appear to be associated with different types of care.

  5. Elevated prolactin levels immediately precede decisions to babysit by male meerkat helpers.

    PubMed

    Carlson, Anne A; Russell, Andrew F; Young, Andrew J; Jordan, Neil R; McNeilly, Alan S; Parlow, Al F; Clutton-Brock, Tim

    2006-06-01

    Recent studies suggest that decisions to care for the offspring of others in societies of cooperative vertebrates may have a hormonal basis. The crucial question of whether changes in hormone levels immediately precede or merely follow bouts of offspring care, however, remains largely unanswered. Here, we show that in wild groups of cooperatively breeding meerkats, male helpers that decided to babysit for the day had significantly higher levels of prolactin, coupled with lower levels of cortisol, before initiating a babysitting session compared with similarly aged individuals that decided to forage. In addition, these hormonal differences disappeared over the course of the day, suggesting that hormone levels changed in a fundamentally different way in meerkats that babysat versus those that foraged. In contrast, long-term contributions to babysitting were not significantly associated with plasma levels of prolactin, cortisol, or testosterone in individual male helpers. Our results show, for the first time, that elevated levels of prolactin may immediately precede bouts of helping behavior but differ from recent findings on the same study population in which plasma levels of cortisol, but not prolactin, were significantly and positively associated with rates of pup feeding by male helpers. Together, these results lend significant weight to the idea that decisions to help in cooperative vertebrates have a hormonal basis, although different hormones appear to be associated with different types of care. PMID:16527276

  6. The influence of flexible management practices on the sharing of experiential knowledge in the workplace: a case study of food service helpers.

    PubMed

    Ledoux, Elise; Cloutier, Esther; Fournier, Pierre-Sébastien

    2012-01-01

    Previous studies have shown that the job knowledge and prudent knowledge of experienced workers constitute a wealth that needs to be shared in workplaces to promote worker integration, job retention and occupational health and safety. It appears, however, that certain management practices undermine this knowledge sharing process. This case study of food service helpers in institutional food service departments is part of a research project aimed at comparing the impact of different work organization methods on knowledge sharing in the workplace on the basis of case studies carried out in several organizations. The results of this case study reveal that by destabilizing and weakening the work teams, flexible management practices create an environment that is not conducive to experiential knowledge sharing. PMID:22317521

  7. N-acetylglucosamine inhibits T-helper 1 (Th1)/T-helper 17 (Th17) cell responses and treats experimental autoimmune encephalomyelitis.

    PubMed

    Grigorian, Ani; Araujo, Lindsey; Naidu, Nandita N; Place, Dylan J; Choudhury, Biswa; Demetriou, Michael

    2011-11-18

    Current treatments and emerging oral therapies for multiple sclerosis (MS) are limited by effectiveness, cost, and/or toxicity. Genetic and environmental factors that alter the branching of Asn (N)-linked glycans result in T cell hyperactivity, promote spontaneous inflammatory demyelination and neurodegeneration in mice, and converge to regulate the risk of MS. The sugar N-acetylglucosamine (GlcNAc) enhances N-glycan branching and inhibits T cell activity and adoptive transfer experimental autoimmune encephalomyelitis (EAE). Here, we report that oral GlcNAc inhibits T-helper 1 (Th1) and T-helper 17 (Th17) responses and attenuates the clinical severity of myelin oligodendrocyte glycoprotein (MOG)-induced EAE when administered after disease onset. Oral GlcNAc increased expression of branched N-glycans in T cells in vivo as shown by high pH anion exchange chromatography, MALDI-TOF mass spectroscopy and FACS analysis with the plant lectin l-phytohemagglutinin. Initiating oral GlcNAc treatment on the second day of clinical disease inhibited MOG-induced EAE as well as secretion of interferon-γ, tumor necrosis factor-α, interleukin-17, and interleukin-22. In the more severe 2D2 T cell receptor transgenic EAE model, oral GlcNAc initiated after disease onset also inhibits clinical disease, except for those with rapid lethal progression. These data suggest that oral GlcNAc may provide an inexpensive and nontoxic oral therapeutic agent for MS that directly targets an underlying molecular mechanism causal of disease. PMID:21965673

  8. Necessary and sufficient role for T helper cells to prevent fungal dissemination in allergic lung disease.

    PubMed

    Porter, Paul C; Roberts, Luz; Fields, Anna; Knight, Morgan; Qian, Yuping; Delclos, George L; Han, Shuhua; Kheradmand, Farrah; Corry, David B

    2011-11-01

    Mucosal immune responses to fungal infection range from T helper type 2 (Th2) cell-directed allergic inflammation to Th1-predominant neutrophilic inflammation, but the mechanisms directing these divergent mucosal immune outcomes and the role of T cells in host defense against mucosal fungal infections are not known. Here we examined the mouse mucosal immune responses to 12 filamentous environmental fungal species over a broad range of exposure doses and determined the requirement of T cells for host defense. For all tested fungi, low-grade conidium exposures induced Th2- and eosinophil-predominant allergic lung disease, whereas higher exposures led to rapid conversion to neutrophil- and Th1 cell-predominant inflammation, a phenomenon we term immune phenotype switching. All fungal exposure doses were further linked to the secretion of interleukin-17A (IL-17A). Fungal infections with Curvularia lunata and Aspergillus fumigatus were typically confined to the airway during allergic inflammation but became locally invasive and disseminated to the brain at higher conidium challenge doses, in association with predominant Th1 responses. Fungal dissemination occurred at relatively low challenge doses with the conidia of Aspergillus fumigatus administered to recombinase activating gene 1 (Rag-1)-deficient mice, which lack B and T cells, but B cell-deficient μMT mice and T helper cell-reconstituted Rag-1-deficient mice were comparable to wild-type mice in preventing fungal dissemination. Our findings demonstrate that Th2 cell-predominant allergic responses followed by immune phenotype switching and fungal dissemination are highly predictable outcomes with progressive fungal infectious burdens and that T helper cell responses are protective against lethal fungal dissemination.

  9. The effect of neutral helper lipids on the structure of cationic lipid monolayers

    PubMed Central

    Dabkowska, A. P.; Barlow, D. J.; Hughes, A. V.; Campbell, R. A.; Quinn, P. J.; Lawrence, M. J.

    2012-01-01

    Successful drug delivery via lipid-based systems has often been aided by the incorporation of ‘helper lipids’. While these neutral lipids enhance the effectiveness of cationic lipid-based delivery formulations, many questions remain about the nature of their beneficial effects. The structure of monolayers of the cationic lipid dimethyldioctadecylammonium bromide (DODAB) alone, and mixed with a neutral helper lipid, either diolelyphosphatidylethanolamine or cholesterol at a 1 : 1 molar ratio was investigated at the air–water interface using a combination of surface pressure–area isotherms, Brewster angle microscopy (BAM) and specular neutron reflectivity in combination with contrast variation. BAM studies showed that while pure DODAB and DODAB with cholesterol monolayers showed fairly homogeneous surfaces, except in the regions of phase transition, monolayers of DODAB with diolelyphosphatidylethanolamine were, in contrast, inhomogeneous exhibiting irregular bean-shaped domains throughout. Neutron reflectivity data showed that while the thickness of the DODAB monolayer increased from 17 to 24 Å as it was compressed from a surface pressure of 5–40 mN m−1, the thickness of the helper lipid-containing monolayers, over the same range of surface pressures, was relatively invariant at between 25 and 27 Å. In addition, the monolayers containing diolelyphosphatidylethanolamine were found to be more heavily hydrated than the monolayers of cationic lipid, alone or in combination with cholesterol, with hydration levels of 18 molecules of water per molecule of lipid being recorded for the diolelyphosphatidylethanolamine-containing monolayers at a surface pressure of 30 mN m−1 compared with only six and eight molecules of water per molecule of lipid for the pure DODAB monolayer and the cholesterol-containing DODAB monolayer, respectively. PMID:21831895

  10. Shifted T Helper Cell Polarization in a Murine Staphylococcus aureus Mastitis Model.

    PubMed

    Zhao, Yanqing; Zhou, Ming; Gao, Yang; Liu, Heyuan; Yang, Wenyu; Yue, Jinhua; Chen, Dekun

    2015-01-01

    Mastitis, one of the most costly diseases in dairy ruminants, is an inflammation of the mammary gland caused by pathogenic infection. The mechanisms of adaptive immunity against pathogens in mastitis have not been fully elucidated. To investigate T helper cell-mediated adaptive immune responses, we established a mastitis model by challenge with an inoculum of 4 × 106 colony-forming units of Staphylococcus aureus in the mammary gland of lactating mice, followed by quantification of bacterial burden and histological analysis. The development of mastitis was accompanied by a significant increase in both Th17 and Th1 cells in the mammary gland. Moreover, the relative expression of genes encoding cytokines and transcription factors involved in the differentiation and function of these T helper cells, including Il17, Rorc, Tgfb, Il1b, Il23, Ifng, Tbx21, and Il12, was greatly elevated in the infected mammary gland. IL-17 is essential for neutrophil recruitment to infected mammary gland via CXC chemokines, whereas the excessive IL-17 production contributes to tissue damage in mastitis. In addition, a shift in T helper cell polarization toward Th2 and Treg cells was observed 5 days post-infection, and the mRNA expression of the anti-inflammatory cytokine Il10 was markedly increased at day 7 post-infection. These results indicate that immune clearance of Staphylococcus aureus in mastitis is facilitated by the enrichment of Th17, Th1 and Th2 cells in the mammary gland mediated by pro-inflammatory cytokine production, which is tightly regulated by Treg cells and the anti-inflammatory cytokine IL-10.

  11. CD4 T-helper cell cytokine phenotypes and antibody response following tetanus toxoid booster immunization.

    PubMed

    Livingston, Kimberly A; Jiang, Xiaowen; Stephensen, Charles B

    2013-04-30

    Routine methods for enumerating antigen-specific T-helper cells may not identify low-frequency phenotypes such as Th2 cells. We compared methods of evaluating such responses to identify tetanus toxoid- (TT) specific Th1, Th2, Th17 and IL10(+) cells. Eight healthy subjects were given a TT booster vaccination. Blood was drawn before, 3, 7, 14, and 28days after vaccination and peripheral blood mononuclear cells (PBMC) were cultured for 7days with TT, negative control (diluent), and a positive control (Staphylococcus enterotoxin B [SEB]). Activation markers (CD25 and CD69) were measured after 44h (n=8), cytokines in supernatant after 3 and 7days, and intracellular cytokine staining (ICS) of proliferated cells (identified by dye dilution) after 7days (n=6). Vaccination increased TT-specific expression of CD25 and CD69 on CD3(+)CD4(+) lymphocytes, and TT-specific proliferation at 7, 14 and 28days post vaccination. Vaccination induced TT-specific Th1 (IFN-γ, TNF-α, and IL-2) Th2 (IL-13, IL-5, and IL-4), Th17 (IL-17A) and IL-10(+) cells as measured by ICS. TT-specific Th1 cells were the most abundant (12-15% of all TT-specific CD4(+) T-cells) while IL10(+) (1.8%) Th17 (1.1%) and Th2 cells (0.2-0.6%) were less abundant. TT-specific cytokine concentrations in PBMC supernatants followed the same pattern where a TT-specific IL-9 response was also seen. In conclusion, TT booster vaccination induced a broad T-helper cell response. This method of evaluating cytokine phenotypes may be useful in examining the impact of nutrition and environmental conditions on the plasticity of T-helper cell memory responses.

  12. Shifted T Helper Cell Polarization in a Murine Staphylococcus aureus Mastitis Model

    PubMed Central

    Zhao, Yanqing; Zhou, Ming; Gao, Yang; Liu, Heyuan; Yang, Wenyu; Yue, Jinhua; Chen, Dekun

    2015-01-01

    Mastitis, one of the most costly diseases in dairy ruminants, is an inflammation of the mammary gland caused by pathogenic infection. The mechanisms of adaptive immunity against pathogens in mastitis have not been fully elucidated. To investigate T helper cell-mediated adaptive immune responses, we established a mastitis model by challenge with an inoculum of 4 × 106 colony-forming units of Staphylococcus aureus in the mammary gland of lactating mice, followed by quantification of bacterial burden and histological analysis. The development of mastitis was accompanied by a significant increase in both Th17 and Th1 cells in the mammary gland. Moreover, the relative expression of genes encoding cytokines and transcription factors involved in the differentiation and function of these T helper cells, including Il17, Rorc, Tgfb, Il1b, Il23, Ifng, Tbx21, and Il12, was greatly elevated in the infected mammary gland. IL-17 is essential for neutrophil recruitment to infected mammary gland via CXC chemokines, whereas the excessive IL-17 production contributes to tissue damage in mastitis. In addition, a shift in T helper cell polarization toward Th2 and Treg cells was observed 5 days post-infection, and the mRNA expression of the anti-inflammatory cytokine Il10 was markedly increased at day 7 post-infection. These results indicate that immune clearance of Staphylococcus aureus in mastitis is facilitated by the enrichment of Th17, Th1 and Th2 cells in the mammary gland mediated by pro-inflammatory cytokine production, which is tightly regulated by Treg cells and the anti-inflammatory cytokine IL-10. PMID:26230498

  13. The role of Tec family kinases in the regulation of T-helper-cell differentiation.

    PubMed

    Boucheron, Nicole; Ellmeier, Wilfried

    2012-04-01

    ABSTRACT Members of the Tec kinase family (Tec, Btk, Itk, Rlk, and Bmx) play an important role during innate and adaptive immune responses, and mutations in Tec family kinases are linked with immunodeficiencies in humans and mice. Three members of the Tec kinase family are expressed in T cells (Tec, Itk, and Rlk), and biochemical and genetic studies have revealed important roles for Tec family kinases during T-cell development and in the control of T-cell function. Here the authors review the role of Tec family kinases in the regulation of T-helper-cell differentiation. PMID:22449074

  14. Developing a pro-regenerative biomaterial scaffold microenvironment requires T helper 2 cells.

    PubMed

    Sadtler, Kaitlyn; Estrellas, Kenneth; Allen, Brian W; Wolf, Matthew T; Fan, Hongni; Tam, Ada J; Patel, Chirag H; Luber, Brandon S; Wang, Hao; Wagner, Kathryn R; Powell, Jonathan D; Housseau, Franck; Pardoll, Drew M; Elisseeff, Jennifer H

    2016-04-15

    Immune-mediated tissue regeneration driven by a biomaterial scaffold is emerging as an innovative regenerative strategy to repair damaged tissues. We investigated how biomaterial scaffolds shape the immune microenvironment in traumatic muscle wounds to improve tissue regeneration. The scaffolds induced a pro-regenerative response, characterized by an mTOR/Rictor-dependent T helper 2 pathway that guides interleukin-4-dependent macrophage polarization, which is critical for functional muscle recovery. Manipulating the adaptive immune system using biomaterials engineering may support the development of therapies that promote both systemic and local pro-regenerative immune responses, ultimately stimulating tissue repair. PMID:27081073

  15. Developing a pro-regenerative biomaterial scaffold microenvironment requires T helper 2 cells

    PubMed Central

    Sadtler, Kaitlyn; Estrellas, Kenneth; Allen, Brian W.; Wolf, Matthew T.; Fan, Hongni; Tam, Ada J.; Patel, Chirag H.; Luber, Brandon S.; Wang, Hao; Wagner, Kathryn R.; Powell, Jonathan D.; Housseau, Franck; Pardoll, Drew M.

    2016-01-01

    Immune-mediated tissue regeneration driven by a biomaterial scaffold is emerging as an innovative regenerative strategy to repair damaged tissues. We investigated how biomaterial scaffolds shape the immune microenvironment in traumatic muscle wounds to improve tissue regeneration. The scaffolds induced a pro-regenerative response, characterized by an mTOR/Rictor-dependent T helper 2 pathway that guides interleukin-4–dependent macrophage polarization, which is critical for functional muscle recovery. Manipulating the adaptive immune system using biomaterials engineering may support the development of therapies that promote both systemic and local pro-regenerative immune responses, ultimately stimulating tissue repair. PMID:27081073

  16. Scalable Memory Registration for High-Performance Networks Using Helper Threads

    SciTech Connect

    Li, Dong; Cameron, Kirk W.; Nikolopoulos, Dimitrios; de Supinski, Bronis R.; Schulz, Martin

    2011-01-01

    Remote DMA (RDMA) enables high performance networks to reduce data copying between an application and the operating system (OS). However RDMA operations in some high performance networks require communication memory explicitly registered with the network adapter and pinned by the OS. Memory registration and pinning limits the flexibility of the memory system and reduces the amount of memory that user processes can allocate. These issues become more significant on multicore platforms, since registered memory demand grows linearly with the number of processor cores. In this paper we propose a new memory registration/deregistration strategy to reduce registered memory on multicore architectures for HPC applications. We hide the cost of dynamic memory management by offloading all dynamic memory registration and deregistration requests to a dedicated memory management helper thread. We investigate design policies and performance implications of the helper thread approach. We evaluate our framework with the NAS parallel benchmarks, for which our registration scheme significantly reduces the registered memory (23.62% on average and up to 49.39%) and avoids memory registration/deregistration costs for reused communication memory. We show that our system enables the execution of problem sizes that could not complete under existing memory registration strategies.

  17. Phenotypically distinct helper NK cells are required for gp96-mediated anti-tumor immunity

    PubMed Central

    Sedlacek, Abigail L.; Kinner-Bibeau, Lauren B.; Binder, Robert J.

    2016-01-01

    A number of Heat Shock Proteins (HSPs), in the extracellular environment, are immunogenic. Following cross-presentation of HSP-chaperoned peptides by CD91+ antigen presenting cells (APCs), T cells are primed with specificity for the derivative antigen-bearing cell. Accordingly, tumor-derived HSPs are in clinical trials for cancer immunotherapy. We investigate the role of NK cells in gp96-mediated anti-tumor immune responses given their propensity to lyse tumor cells. We show that gp96-mediated rejection of tumors requires a unique and necessary helper role in NK cells. This helper role occurs during the effector phase of the anti-tumor immune response and is required for T cell and APC function. Gp96 activates NK cells indirectly via APCs to a phenotype distinct from NK cells activated by other mechanisms such as IL-2. While NK cells have both lytic and cytokine producing properties, we show that gp96 selectively activates cytokine production in NK cells, which is important in the HSP anti-tumor immune response, and leaves their cytotoxic capacity unchanged. PMID:27431727

  18. BRG1-Mediated Chromatin Remodeling Regulates Differentiation and Gene Expression of T Helper Cells▿ †

    PubMed Central

    Wurster, Andrea L.; Pazin, Michael J.

    2008-01-01

    During T helper cell differentiation, distinct programs of gene expression play a key role in defining the immune response to an environmental challenge. How chromatin remodeling events at the associated cytokine loci control differentiation is not known. We found that the ATP-dependent remodeling enzyme subunit BRG1 was required for T helper 2 (Th2) differentiation and Th2 cytokine transcription. BRG1 binding to cytokine genes was regulated by the extent of differentiation, the extent of activation, and cell fate. BRG1 was required for some features of the chromatin structure in target genes (DNase I hypersensitivity and histone acetylation), suggesting that BRG1 remodeling activity was directly responsible for changes in gene expression. NFAT and STAT6 activity were required for BRG1 recruitment to the Th2 locus control region, and STAT6 associated with BRG1 in a differentiation-inducible manner, suggesting direct recruitment of BRG1 to the bound loci. Together, these findings suggest BRG1 interprets differentiation signals and plays a causal role in gene regulation, chromatin structure, and cell fate. PMID:18852284

  19. The Special Relationship in the Development and Function of T Helper 17 and Regulatory T Cells.

    PubMed

    Lochner, Matthias; Wang, Zuobai; Sparwasser, Tim

    2015-01-01

    T helper 17 (Th17) cells play an essential role in the clearance of extracellular pathogenic bacteria and fungi. However, this subset is critically involved in the pathology of many autoimmune diseases, e.g., psoriasis, multiple sclerosis, allergy, rheumatoid arthritis, and inflammatory bowel diseases in humans. Therefore, Th17 responses need to be tightly regulated in vivo to mediate effective host defenses against pathogens without causing excessive host tissue damage. Foxp3(+) regulatory T (Treg) cells play an important role in maintaining peripheral tolerance to self-antigens and in counteracting the inflammatory activity of effector T helper cell subsets. Although Th17 and Treg cells represent two CD4(+) T cell subsets with opposing principal functions, these cell types are functionally connected. In this review, we will first give an overview on the biology of Th17 cells and describe their development and in vivo function, followed by an account on the special developmental relationship between Th17 and Treg cells. We will describe the identification of Treg/Th17 intermediates and consider their lineage stability and function in vivo. Finally, we will discuss how Treg cells may regulate the Th17 cell response in the context of infection and inflammation, and elude on findings demonstrating that Treg cells can also have a prominent function in promoting the differentiation of Th17 cells. PMID:26615094

  20. Cxc Chemokine Receptor 5 Expression Defines Follicular Homing T Cells with B Cell Helper Function

    PubMed Central

    Schaerli, Patrick; Willimann, Katharina; Lang, Alois B.; Lipp, Martin; Loetscher, Pius; Moser, Bernhard

    2000-01-01

    Leukocyte traffic through secondary lymphoid tissues is finely tuned by chemokines. We have studied the functional properties of a human T cell subset marked by the expression of CXC chemokine receptor 5 (CXCR5). Memory but not naive T cells from tonsils are CXCR5+ and migrate in response to the B cell–attracting chemokine 1 (BCA-1), which is selectively expressed by reticular cells and blood vessels within B cell follicles. Tonsillar CXCR5+ T cells do not respond to other chemokines present in secondary lymphoid tissues, including secondary lymphoid tissue chemokine (SLC), EBV-induced molecule 1 ligand chemokine (ELC), and stromal cell–derived factor 1 (SDF-1). The involvement of tonsillar CXCR5+ T cells in humoral immune responses is suggested by their localization in the mantle and light zone germinal centers of B cell follicles and by the concomitant expression of activation and costimulatory markers, including CD69, HLA-DR, and inducible costimulator (ICOS). Peripheral blood CXCR5+ T cells also belong to the CD4+ memory T cell subset but, in contrast to tonsillar cells, are in a resting state and migrate weakly to chemokines. CXCR5+ T cells are very inefficient in the production of cytokines but potently induce antibody production during coculture with B cells. These properties portray CXCR5+ T cells as a distinct memory T cell subset with B cell helper function, designated here as follicular B helper T cells (TFH). PMID:11104798

  1. TCF1 Is Required for the T Follicular Helper Cell Response to Viral Infection.

    PubMed

    Wu, Tuoqi; Shin, Hyun Mu; Moseman, E Ashley; Ji, Yun; Huang, Bonnie; Harly, Christelle; Sen, Jyoti M; Berg, Leslie J; Gattinoni, Luca; McGavern, Dorian B; Schwartzberg, Pamela L

    2015-09-29

    T follicular helper (TFH) and T helper 1 (Th1) cells generated after viral infections are critical for the control of infection and the development of immunological memory. However, the mechanisms that govern the differentiation and maintenance of these two distinct lineages during viral infection remain unclear. We found that viral-specific TFH and Th1 cells showed reciprocal expression of the transcriptions factors TCF1 and Blimp1 early after infection, even before the differential expression of the canonical TFH marker CXCR5. Furthermore, TCF1 was intrinsically required for the TFH cell response to viral infection; in the absence of TCF1, the TFH cell response was severely compromised, and the remaining TCF1-deficient TFH cells failed to maintain TFH-associated transcriptional and metabolic signatures, which were distinct from those in Th1 cells. Mechanistically, TCF1 functioned through forming negative feedback loops with IL-2 and Blimp1. Our findings demonstrate an essential role of TCF1 in TFH cell responses to viral infection. PMID:26365183

  2. OX40 Ligand Contributes to Human Lupus Pathogenesis by Promoting T Follicular Helper Response.

    PubMed

    Jacquemin, Clément; Schmitt, Nathalie; Contin-Bordes, Cécile; Liu, Yang; Narayanan, Priya; Seneschal, Julien; Maurouard, Typhanie; Dougall, David; Davizon, Emily Spence; Dumortier, Hélène; Douchet, Isabelle; Raffray, Loïc; Richez, Christophe; Lazaro, Estibaliz; Duffau, Pierre; Truchetet, Marie-Elise; Khoryati, Liliane; Mercié, Patrick; Couzi, Lionel; Merville, Pierre; Schaeverbeke, Thierry; Viallard, Jean-François; Pellegrin, Jean-Luc; Moreau, Jean-François; Muller, Sylviane; Zurawski, Sandy; Coffman, Robert L; Pascual, Virginia; Ueno, Hideki; Blanco, Patrick

    2015-06-16

    Increased activity of T follicular helper (Tfh) cells plays a major pathogenic role in systemic lupus erythematosus (SLE). However, the mechanisms that cause aberrant Tfh cell responses in SLE remain elusive. Here we showed the OX40 ligand (OX40L)-OX40 axis contributes to the aberrant Tfh response in SLE. OX40L was expressed by myeloid antigen-presenting cells (APCs), but not B cells, in blood and in inflamed tissues in adult and pediatric SLE patients. The frequency of circulating OX40L-expressing myeloid APCs positively correlated with disease activity and the frequency of ICOS(+) blood Tfh cells in SLE. OX40 signals promoted naive and memory CD4(+) T cells to express multiple Tfh cell molecules and were sufficient to induce them to become functional B cell helpers. Immune complexes containing RNA induced OX40L expression on myeloid APCs via TLR7 activation. Our study provides a rationale to target the OX40L-OX40 axis as a therapeutic modality for SLE. PMID:26070486

  3. Views on helper/cytotoxic lineage choice from a bottom-up approach.

    PubMed

    Taniuchi, Ichiro

    2016-05-01

    There has been speculation as to how bi-potent CD4(+)  CD8(+) double-positive precursor thymocytes choose their distinct developmental fate, becoming either CD4(+) helper or CD8(+) cytotoxic T cells. Based on the clear correlation of αβT cell receptor (TCR) specificity to major histocompatibility complex (MHC) classes with this lineage choice, various studies have attempted to resolve this question by examining the cellular signaling events initiated by TCR engagements, a strategy referred to as a 'top-down' approach. On the other hand, based on the other correlation of CD4/CD8 co-receptor expression with its selected fate, other studies have addressed this question by gradually unraveling the sequential mechanisms that control the phenotypic outcome of this fate decision, a method known as the 'bottom-up' approach. Bridging these two approaches will contribute to a more comprehensive understanding of how TCR signals are coupled with developmental programs in the nucleus. Advances made during the last two decades seemed to make these two approaches more closely linked. For instance, identification of two transcription factors, ThPOK and Runx3, which play central roles in the development of helper and cytotoxic lineages, respectively, provided significant insights into the transcriptional network that controls a CD4/CD8 lineage choice. This review summarizes achievements made using the 'bottom-up' approach, followed by a perspective on future pathways toward coupling TCR signaling with nuclear programs. PMID:27088909

  4. Nitric oxide inhibits the secretion of T-helper 1- and T-helper 2-associated cytokines in activated human T cells.

    PubMed Central

    Bauer, H; Jung, T; Tsikas, D; Stichtenoth, D O; Frölich, J C; Neumann, C

    1997-01-01

    Mechanisms regulating the balance of T-helper 1 (Th1) and T-helper 2 (Th2) immune responses are of great interest as they may determine the outcome of allergic and infectious diseases. Recently, in mice, nitric oxide (NO), a powerful modulator of inflammation, has been reported to preferentially down-regulate Th1-mediated immune responses. In the present study, we investigated the effect of NO on the production of Th1- and Th2-associated cytokines by activated human T cells and human T-cell clones. Cytokine secretion was measured in the presence of the NO-donating agents 3-morpholinosydnonimine (SIN-1) and S-nitroso-N-acetylpenicillamine (SNAP). Both NO-donors markedly inhibited the release of interferon-gamma (IFN-gamma), interleukin-2 (IL-2), IL-5, IL-10 and IL-4 by anti-CD3 activated T cells. A preferential inhibition of Th1-associated cytokines was not observed. Neither was nitrite found in the supernatants of activated T cells, nor was specific mRNA for inducible and constitutive NO synthase detectable, indicating that T cells themselves did not contribute to the observed effect of the NO donors. Costimulation with anti-CD28 monoclonal antibodies (mAb) prevented SIN-1/SNAP-mediated down-regulation of cytokine production only in part. In contrast, when T cells were stimulated by phorbol-ester and ionomycin, they were refractory to SIN-1-induced inhibition of cytokine production. When SIN-1 was added after the onset of anti-CD3 stimulation, the inhibitory effect was found to be less pronounced, indicating that SIN-1 may interfere with early signal transduction events. The addition of superoxide dismutase (SOD) and catalase did not restore the effects of SIN-1, demonstrating that the inhibition of cytokines was due to NO and not to oxygen intermediates. Furthermore, 8-Br-cGMP-mediated increase of intracellular cGMP caused the same pattern of cytokine inhibition as observed with SIN-1 and SNAP. Using a single cell assay, these agents were shown to reduce the

  5. Ribavirin contributes to eradicate hepatitis C virus through polarization of T helper 1/2 cell balance into T helper 1 dominance

    PubMed Central

    Nakatsuka, Katsuhisa; Atsukawa, Masanori; Shimizu, Masumi; Takahashi, Hidemi; Kawamoto, Chiaki

    2015-01-01

    The mechanism of action of ribavirin (RBV) as an immunomodulatory and antiviral agent and its clinical significance in the future treatment of patients with hepatitis C virus (HCV) infection are reviewed. RBV up-regulates type 1 and/or 2 cytokines to modulate the T helper (Th) 1/2 cell balance to Th1 dominance. Examination of co-stimulatory signaling indicated that RBV down-modulates inducible co-stimulator on Th cells, which contributes to differentiating naïve Th cells into Th2 cells while reducing their interleukin-10 production. The effects on T-regulatory (Treg) cells were also investigated, and RBV inhibited the differentiation of naïve Th cells into adaptive Treg cells by down-modulating forkhead box-P3. These findings indicate that RBV mainly down-regulates the activity of Th2 cells, resulting in the maintenance of Th1 activity that contributes to abrogating HCV-infected hepatocytes. Although an interferon-free treatment regimen exhibits almost the same efficacy without serious complications, regimens with RBV will be still be used because of their ability to facilitate the cellular immune response, which may contribute to reducing the development of hepatocellular carcinogenesis in patients infected with HCV. PMID:26557951

  6. Abundance and specificity of influenza reactive circulating memory follicular helper and non-follicular helper CD4 T cells in healthy adults.

    PubMed

    Leddon, Scott A; Richards, Katherine A; Treanor, John J; Sant, Andrea J

    2015-09-01

    CD4 T-cell responses are functionally complex and regulate many aspects of innate and adaptive immunity. Follicular helper (Tfh) cells are CD4 T cells specialized to support B-cell production of isotype-switched, high-affinity antibody. So far, studies of Tfh cells in humans have focused on their differentiation requirements, with little research devoted to their antigen specificity. Here, after separating circulating human memory CD4 T cells based on expression of CXCR5, a signature marker of Tfh, we have quantified and assayed the influenza protein antigen specificity of blood Tfh cells and CD4 T cells lacking this marker. Through the use of peptide pools derived from nucleoprotein (NP) or haemagglutinin (HA) and a panel of human donors, we have discovered that circulating Tfh cells preferentially recognize peptide epitopes from HA while cells lacking CXCR5 are enriched for specificity toward NP. These studies suggest that reactive CD4 T cells specific for distinct viral antigens may have generalized differences in their functional potential due to their previous stimulation history. PMID:26094691

  7. The role of helper lipids in cationic liposome-mediated gene transfer.

    PubMed Central

    Hui, S W; Langner, M; Zhao, Y L; Ross, P; Hurley, E; Chan, K

    1996-01-01

    In the procedure for cationic liposome-mediated transfection, the cationic lipid is usually mixed with a "helper lipid" to increase its transfection potency. The importance of helper lipids, including dioleoylphosphatidylcholine (DOPC) and phosphatidylethanolamine (dioleoyl PE), DO was examined. Freeze-fracture electron microscopy of DNA:cationic complexes containing the pSV-beta-GAL plasmid DNA, the cationic lipid dioleoyl trimethylammonium propane, and these helper lipids showed that the most efficient mixtures were aggregates of ensheathed DNA and fused liposomes. PE-containing complexes aggregated rapidly when added to culture media containing polyanions, whereas PC-containing complexes did not. However, more granules of PC-containing complexes were formed on cell surfaces after the complexes were added to Chinese hamster ovary (CHO) cells in transfection media. Pronase treatment inhibited transfection, whereas dilute poly-L-lysine enhanced transfection, indicating that the attachment of DNA:liposome complexes to cell surfaces was mediated by electrostatic interaction. Fluorescence spectroscopy studies confirmed that more PC-containing complexes than PE-containing complexes were associated with CHO cells, and that more PC-containing complexes were located in a low pH environment (likely to be within endosomes) with time. Cytochalasin-B had a stronger inhibitory effect on PC-containing liposome-mediated than on PE-containing liposome-mediated transfection. Confocal microscopic recording of the fluorescently label lipid and DNA uptake process indicated that many granules of DNA:cationic liposome complexes were internalized as a whole, whereas some DNA aggregates were left out on the cell surfaces after liposomes of the complexes fused with the plasma membranes. For CHO cells, endocytosis seems to be the main uptake pathway of DNA:cationic liposome complexes. More PC-containing granules than PE-containing granules were formed on cell surfaces by cytoskeleton

  8. "Cancer Survivors" as Voluntary Helpers in Cancer Associations in France. Limits of the Balance between Service Offer and Social Demand.

    PubMed

    Pourtau, Lionel; Taleb, Sabrine; De Oliveira, Jean-Philippe; Sagatchian, Mahasti; Ferrand-Bechmann, Dan

    2016-09-01

    Historically, in France, cancer associations have been managed by doctors. Despite this, the French healthcare system has increasingly encouraged them to attract voluntary helpers who are not health workers. This development has given rise to the question of the competence and legitimacy of voluntary workers in cancer associations. The aim of the present study was to identify the skills possessed by voluntary helpers who have survived the disease and the extent to which their skills meet the needs of cancer associations in responding to the demands that have emerged in this new context. This is a qualitative study based on data collected during semi-directed interviews, focus group sessions and on-site observations in a variety of French cancer associations. Categorical and thematic analyses were then carried out separately for each ethnographic method used. The study showed that because the commitment of survivor voluntary helpers derives from their own experience of the disease, it is inconsistent with the fulfilment of the association's collective aims, such as the search for funding or project development. These helpers nevertheless play an important role that involves a special link between the individual and the group, between the community and society. To conclude, "involved" volunteers have to reconcile their individual expectations with the association's collective aims.

  9. More Water, Madam? An ESL Curriculum for Service Helpers in Full-Service and Fast-Food Restaurants.

    ERIC Educational Resources Information Center

    Cwach, Marlin Day; Gravely, Mary Liles

    This document, which was developed as a cooperative effort between the business and education communities in Denver, presents an English-as-a-second-language curriculum for service helpers in full-service and fast food restaurants. The curriculum consists of five lessons targeted toward high intermediate to advanced nonnative speakers who work in…

  10. Development of a competitive PCR method for physical titration of recombinant EBV vector in a helper-dependent packaging system.

    PubMed

    Wang, J; Vos, J M

    2001-06-01

    Epstein-Barr virus (EBV) is a gamma-herpesvirus with B lymphotropism and a double-stranded DNA genome of 172 kb that is episomally maintained in permissive cells during latency. EBV-based vectors containing minimal cis elements for replication, amplification, and helper-dependent packaging in a producer cell line HH514 have been developed to deliver therapeutic/suicide transgenes as infectious viral particles (miniEBV) to EBV-transformed B lymphoblastoid cells or B lymphoma cells. A quantitative, competitive PCR-based assay was developed to determine the relative packaging efficiencies of miniEBV and helper P3HR1 coproduced in HH514 cells. This provides a rapid and accurate quantitation of the physical titer of the virus preparation, which helps preserve the biological titer of the virus preparation and increase the efficiency of transgene delivery by miniEBV infection. In addition, it provides a sensitive and accurate way to evaluate future development of a helper-free packaging system by detecting any possible helper virus contamination.

  11. Effects of a Peer Helping Training Program on Helping Skills and Self-Growth of Peer Helpers

    ERIC Educational Resources Information Center

    Aladag, Mine; Tezer, Esin

    2009-01-01

    The purpose of this study was to develop a peer helping training program for university students in Turkey and to examine its effectiveness in improving the helping skills and self-growth of peer helpers. A pre-test, post-test, follow-up-test experimental design, involving a treatment and control group, was carried out with a total sample of 31…

  12. T Helper Cells Fate Mapping by Co-stimulatory Molecules and its Functions in Allograft Rejection and Tolerance.

    PubMed

    Abdoli, R; Najafian, N

    2014-01-01

    T cell differentiation is dictated by a combination of T cell receptor (TCR) interaction with an antigen-bound major histocompatibility complex (MHC), and co-stimulatory molecules signal. The co-stimulatory signal can be positive or negative, and amplifying or diminishing the initial signal. However, the secondary co-stimulatory signal is not obligatory and its necessity is dictated, in part, by the stage of T cell development. In the field of transplantation, directing the T cell differentiation process can lead to therapeutic possibilities that promote allograft tolerance, and hinder unfavorable alloimmune responses. Therefore, understanding the details of T cell differentiation process, including the influence of co-stimulatory signals, is of paramount importance. It is important to note there is functional overlap between co-stimulatory molecules. It has been observed that some co-stimulatory signals have different effects on different T cell subsets. Hence, blockade of a co-stimulatory signal pathway, as part of a therapeutic regimen in transplantation, may have far reaching effects beyond the initial therapeutic intent and inhibit co-stimulatory signals necessary for desirable regulatory responses. In this review, co-stimulatory molecules involved in the differentiation of naïve T cells into T helper 1 (Th1), T helper 2 (Th2), T helper 17 (Th17), inducible regulatory T cells (iTregs), and T helper 9 (Th9) cells and their overlap are discussed.

  13. T Helper Cells Fate Mapping by Co-stimulatory Molecules and its Functions in Allograft Rejection and Tolerance

    PubMed Central

    Abdoli, R.; Najafian, N.

    2014-01-01

    T cell differentiation is dictated by a combination of T cell receptor (TCR) interaction with an antigen-bound major histocompatibility complex (MHC), and co-stimulatory molecules signal. The co-stimulatory signal can be positive or negative, and amplifying or diminishing the initial signal. However, the secondary co-stimulatory signal is not obligatory and its necessity is dictated, in part, by the stage of T cell development. In the field of transplantation, directing the T cell differentiation process can lead to therapeutic possibilities that promote allograft tolerance, and hinder unfavorable alloimmune responses. Therefore, understanding the details of T cell differentiation process, including the influence of co-stimulatory signals, is of paramount importance. It is important to note there is functional overlap between co-stimulatory molecules. It has been observed that some co-stimulatory signals have different effects on different T cell subsets. Hence, blockade of a co-stimulatory signal pathway, as part of a therapeutic regimen in transplantation, may have far reaching effects beyond the initial therapeutic intent and inhibit co-stimulatory signals necessary for desirable regulatory responses. In this review, co-stimulatory molecules involved in the differentiation of naïve T cells into T helper 1 (Th1), T helper 2 (Th2), T helper 17 (Th17), inducible regulatory T cells (iTregs), and T helper 9 (Th9) cells and their overlap are discussed. PMID:25184030

  14. Bad Influence?--An Investigation into the Purported Negative Influence of Foreign Domestic Helpers on Children's Second Language English Acquisition

    ERIC Educational Resources Information Center

    Leung, Alex Ho-Cheong

    2012-01-01

    This paper explores the purported negative influence of foreign domestic helpers (FDHs) on child second language acquisition (SLA) by studying Hong Kong Cantonese children's listening ability in second language (L2) English. 31 kindergarten third graders aged 4;6 to 6, and 29 first year secondary students aged 11-14 who have had a Filipino…

  15. Helping effort increases with relatedness in bell miners, but ‘unrelated’ helpers of both sexes still provide substantial care

    PubMed Central

    Wright, Jonathan; McDonald, Paul G.; te Marvelde, Luc; Kazem, Anahita J. N.; Bishop, Charles M.

    2010-01-01

    Indirect fitness benefits from kin selection can explain why non-breeding individuals help raise the young of relatives. However, the evolution of helping by non-relatives requires direct fitness benefits, for example via group augmentation. Here, we examine nest visit rates, load sizes and prey types delivered by breeding pairs and their helpers in the cooperatively breeding bell miner (Manorina melanophrys). In this system, males remain in their natal colony while young females typically disperse, and helpers of both sexes often assist at multiple nests concurrently. We found extremely clear evidence for the expected effect of genetic relatedness on individual helping effort per nest within colonies. This positive incremental effect of kinship was facultative—i.e. largely the result of within-individual variation in helping effort. Surprisingly, no sex differences were detectable in any aspect of helping, and even non-relatives provided substantial aid. Helpers and breeders of both sexes regulated their provisioning effort by responding visit-by-visit to changes in nestling begging. Helping behaviour in bell miners therefore appears consistent with adaptive cooperative investment in the brood, and kin-selected care by relatives. Similar investment by ‘unrelated’ helpers of both sexes argues against direct fitness benefits, but is perhaps explained by kin selection at the colony level. PMID:19846458

  16. Overexpressing target helper genes enhances secretion and glycosylation of recombinant proteins in Pichia pastoris under simulated microgravity.

    PubMed

    Huangfu, Jie; Xu, Yinghua; Li, Chun; Li, Jun

    2016-10-01

    In this study, the potential helper genes were identified through the data analysis of transcriptomic and proteomic profiling in recombinant Pichia pastoris cultured under simulated microgravity (SMG). Co-expressing of four genes PRX1, YAP1, AHA1, and YPT6, involved in the oxidative stress response and protein folding, exhibited promising helper factor effects on the recombinant protein yields in engineered P. pastoris, respectively. When two of the above genes were co-expressed simultaneously, β-glucuronidase (PGUS) specific activity was further increased by 30.3-50.6 % comparing with that of single helper gene, particularly when the oxidative stress response and protein folding genes were both present in the combinations. In addition, co-expressing co-chaperone AHA1 and transcription factor YAP1 not only enhanced PGUS secretion, but also affected its glycosylation. Thus, through deep "omics" analysis of SMG effects, our results provided combined impact of new helper factors to improve the efficacy of recombinant protein secretion and glycosylation in engineered P. pastoris. PMID:27535143

  17. Anchors of Meaning--Helpers of Dialogue: The Use of Images in Production of Relations and Meaning

    ERIC Educational Resources Information Center

    Pedersen, Christina Hee

    2008-01-01

    What is it that images can do that cannot be done by words alone? This article illustrates and discusses how visual expressions act as helpers of dialogue--anchors of meaning. The main argument is that the inclusion of pictorial material is a useful way to develop poststructuralist thinking technologies to further expand our understandings of the…

  18. "Cancer Survivors" as Voluntary Helpers in Cancer Associations in France. Limits of the Balance between Service Offer and Social Demand.

    PubMed

    Pourtau, Lionel; Taleb, Sabrine; De Oliveira, Jean-Philippe; Sagatchian, Mahasti; Ferrand-Bechmann, Dan

    2016-09-01

    Historically, in France, cancer associations have been managed by doctors. Despite this, the French healthcare system has increasingly encouraged them to attract voluntary helpers who are not health workers. This development has given rise to the question of the competence and legitimacy of voluntary workers in cancer associations. The aim of the present study was to identify the skills possessed by voluntary helpers who have survived the disease and the extent to which their skills meet the needs of cancer associations in responding to the demands that have emerged in this new context. This is a qualitative study based on data collected during semi-directed interviews, focus group sessions and on-site observations in a variety of French cancer associations. Categorical and thematic analyses were then carried out separately for each ethnographic method used. The study showed that because the commitment of survivor voluntary helpers derives from their own experience of the disease, it is inconsistent with the fulfilment of the association's collective aims, such as the search for funding or project development. These helpers nevertheless play an important role that involves a special link between the individual and the group, between the community and society. To conclude, "involved" volunteers have to reconcile their individual expectations with the association's collective aims. PMID:26201765

  19. The Potential Role of T Helper Cell 22 and IL-22 in Immunopathogenesis of Multiple Sclerosis

    PubMed Central

    Fard, Nazanin Arjomand; Azizi, Gholamreza

    2016-01-01

    Multiple sclerosis is a complex disease with many different immune cells involved in its pathogenesis. Newly identified T helper cell 22 (Th22) is a subset of CD4+ T cells with specific properties apart from other known CD4+ T cell subsets with distinguished function and gene expression. Th22 cells are characterized by production of a distinct profile of effector cytokines, including interleukin (IL)-22, IL-13, and tumor necrosis factor-α (TNF- α). The frequency of Th22 and related cytokine IL-22 are increased in various autoimmune diseases. Recently, several studies have reported the changes in frequency and function of Th22 in multiple sclerosis. This review discusses the role of Th22 and its cytokine IL-22 in the immunopathogenesis of multiple sclerosis disease. PMID:27672486

  20. TCR ITAM multiplicity is required for the generation of follicular helper T-cells.

    PubMed

    Hwang, SuJin; Palin, Amy C; Li, LiQi; Song, Ki-Duk; Lee, Jan; Herz, Jasmin; Tubo, Noah; Chu, Hamlet; Pepper, Marion; Lesourne, Renaud; Zvezdova, Ekaterina; Pinkhasov, Julia; Jenkins, Marc K; McGavern, Dorian; Love, Paul E

    2015-01-01

    The T-cell antigen receptor (TCR) complex contains 10 copies of a di-tyrosine Immunoreceptor-Tyrosine-based-Activation-Motif (ITAM) that initiates TCR signalling by recruiting protein tyrosine kinases. ITAM multiplicity amplifies TCR signals, but the importance of this capability for T-cell responses remains undefined. Most TCR ITAMs (6 of 10) are contributed by the CD3ζ subunits. We generated 'knock-in' mice that express non-signalling CD3ζ chains in lieu of wild-type CD3ζ. Here we demonstrate that ITAM multiplicity is important for the development of innate-like T-cells and follicular helper T-cells, events that are known to require strong/sustained TCR-ligand interactions, but is not essential for 'general' T-cell responses including proliferation and cytokine production or for the generation of a diverse antigen-reactive TCR repertoire. PMID:25959494

  1. TCR ITAM multiplicity is required for the generation of follicular helper T-cells.

    PubMed

    Hwang, SuJin; Palin, Amy C; Li, LiQi; Song, Ki-Duk; Lee, Jan; Herz, Jasmin; Tubo, Noah; Chu, Hamlet; Pepper, Marion; Lesourne, Renaud; Zvezdova, Ekaterina; Pinkhasov, Julia; Jenkins, Marc K; McGavern, Dorian; Love, Paul E

    2015-05-11

    The T-cell antigen receptor (TCR) complex contains 10 copies of a di-tyrosine Immunoreceptor-Tyrosine-based-Activation-Motif (ITAM) that initiates TCR signalling by recruiting protein tyrosine kinases. ITAM multiplicity amplifies TCR signals, but the importance of this capability for T-cell responses remains undefined. Most TCR ITAMs (6 of 10) are contributed by the CD3ζ subunits. We generated 'knock-in' mice that express non-signalling CD3ζ chains in lieu of wild-type CD3ζ. Here we demonstrate that ITAM multiplicity is important for the development of innate-like T-cells and follicular helper T-cells, events that are known to require strong/sustained TCR-ligand interactions, but is not essential for 'general' T-cell responses including proliferation and cytokine production or for the generation of a diverse antigen-reactive TCR repertoire.

  2. Gene Therapy with Helper-Dependent Adenoviral Vectors: Current Advances and Future Perspectives

    PubMed Central

    Vetrini, Francesco; Ng, Philip

    2010-01-01

    Recombinant Adenoviral vectors represent one of the best gene transfer platforms due to their ability to efficiently transduce a wide range of quiescent and proliferating cell types from various tissues and species. The activation of an adaptive immune response against the transduced cells is one of the major drawbacks of first generation Adenovirus vectors and has been overcome by the latest generation of recombinant Adenovirus, the Helper-Dependent Adenoviral (HDAd) vectors. HDAds have innovative features including the complete absence of viral coding sequences and the ability to mediate high level transgene expression with negligible chronic toxicity. This review summarizes the many aspects of HDAd biology and structure with a major focus on in vivo gene therapy application and with an emphasis on the unsolved issues that these vectors still presents toward clinical application. PMID:21994713

  3. Follicular Helper T (Tfh) Cells in Autoimmune Diseases and Allograft Rejection

    PubMed Central

    Jeon, Yun-Hui

    2016-01-01

    Production of high affinity antibodies for antigens is a critical component for the immune system to fight off infectious pathogens. However, it could be detrimental to our body when the antigens that B cells recognize are of self-origin. Follicular helper T, or Tfh, cells are required for the generation of germinal center reactions, where high affinity antibody-producing B cells and memory B cells predominantly develop. As such, Tfh cells are considered as targets to prevent B cells from producing high affinity antibodies against self-antigens, when high affinity autoantibodies are responsible for immunopathologies in autoimmune disorders. This review article provides an overview of current understanding of Tfh cells and discusses it in the context of animal models of autoimmune diseases and allograft rejections for generation of novel therapeutic interventions. PMID:27574501

  4. T helper cells in murine germinal centers are antigen-specific emigrants that downregulate Thy-1

    PubMed Central

    1996-01-01

    After immunization, activated splenic T cells proliferate in periarteriolar lymphoid sheaths (PALS) and subsequently migrate to the lymphoid follicle where they enter nascent germinal centers. Analysis of TCR V(D)J gene rearrangements indicates extensive emigration, frequently involving more than a single white pulp region. These migrants constitute a unique set of T helper cells that express antigen- specific alpha beta TCR, CD3, and CD4, but little or no Thy-1, a differentiation antigen present on the great majority of peripheral murine T lymphocytes. The origin of CD4+ Thy-1 follicular T cells appears to be the Thy+ population in the PALS, as both sets commonly share identical V(D)J rearrangements. PMID:9064325

  5. The Potential Role of T Helper Cell 22 and IL-22 in Immunopathogenesis of Multiple Sclerosis.

    PubMed

    Fard, Nazanin Arjomand; Azizi, Gholamreza; Mirshafiey, Abbas

    2016-01-01

    Multiple sclerosis is a complex disease with many different immune cells involved in its pathogenesis. Newly identified T helper cell 22 (Th22) is a subset of CD4(+) T cells with specific properties apart from other known CD4(+) T cell subsets with distinguished function and gene expression. Th22 cells are characterized by production of a distinct profile of effector cytokines, including interleukin (IL)-22, IL-13, and tumor necrosis factor-α (TNF- α). The frequency of Th22 and related cytokine IL-22 are increased in various autoimmune diseases. Recently, several studies have reported the changes in frequency and function of Th22 in multiple sclerosis. This review discusses the role of Th22 and its cytokine IL-22 in the immunopathogenesis of multiple sclerosis disease. PMID:27672486

  6. Dysregulated T helper cell differentiation in the absence of interferon regulatory factor 4.

    PubMed

    Lohoff, Michael; Mittrücker, Hans-Willi; Prechtl, Stefan; Bischof, Susi; Sommer, Frank; Kock, Sonja; Ferrick, David A; Duncan, Gordon S; Gessner, Andre; Mak, Tak W

    2002-09-01

    Certain IFN regulatory factor (IRF) transcription factors indirectly influence T helper (Th) cell differentiation by regulating the production of IL-12. Here, we show that IRF4 directly regulates Th cell differentiation in vitro and in vivo during murine leishmaniasis. In the absence of IRF4, IL-12-induced Th1 cell differentiation was compromised, while IL-4 failed to induce Th2 cell differentiation. Instead, IL-4 tended to induce Th1 cells, defined by production of IFN-gamma and TNF. Although early IL-4 signaling was normal in IRF4(-/-) Th cells, the protein GATA-3, a transcription factor critical for Th2 development, was not up-regulated following IL-4 treatment. Retroviral overexpression of GATA-3 rescued Th2 differentiation. Therefore, IRF4 deficiency manifests itself as severely dysregulated Th cell differentiation.

  7. Follicular Helper T (Tfh) Cells in Autoimmune Diseases and Allograft Rejection.

    PubMed

    Jeon, Yun-Hui; Choi, Youn Soo

    2016-08-01

    Production of high affinity antibodies for antigens is a critical component for the immune system to fight off infectious pathogens. However, it could be detrimental to our body when the antigens that B cells recognize are of self-origin. Follicular helper T, or Tfh, cells are required for the generation of germinal center reactions, where high affinity antibody-producing B cells and memory B cells predominantly develop. As such, Tfh cells are considered as targets to prevent B cells from producing high affinity antibodies against self-antigens, when high affinity autoantibodies are responsible for immunopathologies in autoimmune disorders. This review article provides an overview of current understanding of Tfh cells and discusses it in the context of animal models of autoimmune diseases and allograft rejections for generation of novel therapeutic interventions. PMID:27574501

  8. Can follicular helper T cells be targeted to improve vaccine efficacy?

    PubMed Central

    Linterman, Michelle A.; Hill, Danika L.

    2016-01-01

    The success of most vaccines relies on the generation of antibodies to provide protection against subsequent infection; this in turn depends on a robust germinal centre (GC) response that culminates in the production of long-lived antibody-secreting plasma cells. The size and quality of the GC response are directed by a specialised subset of CD4 + T cells: T follicular helper (Tfh) cells. Tfh cells provide growth and differentiation signals to GC B cells and mediate positive selection of high-affinity B cell clones in the GC, thereby determining which B cells exit the GC as plasma cells and memory B cells. Because of their central role in the production of long-lasting humoral immunity, Tfh cells represent an interesting target for rational vaccine design. PMID:26989476

  9. The role of T helper type 17 cells in inflammatory arthritis

    PubMed Central

    Sarkar, S; Cooney, L A; Fox, D A

    2010-01-01

    While T cells have been implicated in the pathogenesis of inflammatory arthritis for more than three decades, the focus on the T helper type 17 (Th17) subset of CD4 T cells and their secreted cytokines, such as interleukin (IL)-17, is much more recent. Proinflammatory actions of IL-17 were first identified in the 1990s, but the delineation of a distinct Th17 subset in late 2005 has sparked great interest in the role of these cells in a broad range of immune-mediated diseases. This review summarizes current understanding of the role of Th17 cells and their products in both animal models of inflammatory arthritis and human immune-driven arthritides. PMID:19758374

  10. Hepatic Delivery of Artificial Micro RNAs Using Helper-Dependent Adenoviral Vectors.

    PubMed

    Crowther, Carol; Mowa, Betty; Arbuthnot, Patrick

    2016-01-01

    The potential of RNA interference (RNAi)-based gene therapy has been demonstrated in many studies. However, clinical application of this technology has been hampered by a paucity of efficient and safe methods of delivering the RNAi activators. Prolonged transgene expression and improved safety of helper-dependent adenoviral vectors (HD AdVs) makes them well suited to delivery of engineered artificial intermediates of the RNAi pathway. Also, AdVs' natural hepatotropism makes them potentially useful for liver-targeted gene delivery. HD AdVs may be used for efficient delivery of cassettes encoding short hairpin RNAs and artificial primary microRNAs to the mouse liver. Methods for the characterization of HD AdV-mediated delivery of hepatitis B virus-targeting RNAi activators are described here.

  11. B–helper neutrophils stimulate immunoglobulin diversification and production in the marginal zone of the spleen

    PubMed Central

    Puga, Irene; Cols, Montserrat; Barra, Carolina M.; He, Bing; Cassis, Linda; Gentile, Maurizio; Comerma, Laura; Chorny, Alejo; Shan, Meimei; Xu, Weifeng; Magri, Giuliana; Knowles, Daniel M.; Tam, Wayne; Chiu, April; Bussel, James B; Serrano, Sergi; Lorente, José Antonio; Bellosillo, Beatriz; Lloreta, Josep; Juanpere, Nuria; Alameda, Francesc; Baró, Teresa; de Heredia, Cristina Díaz; Torán, Núria; Català, Albert; Torrebadell, Montserrat; Fortuny, Claudia; Cusi, Victoria; Carreras, Carmen; Diaz, George A.; Blander, J. Magarian; Farber, Claire-Michèle; Silvestri, Guido; Cunningham-Rundles, Charlotte; Calvillo, Michaela; Dufour, Carlo; Notarangelo, Lucia Dora; Lougaris, Vassilios; Plebani, Alessandro; Casanova, Jean-Laurent; Ganal, Stephanie C.; Diefenbach, Andreas; Aróstegui, Juan Ignacio; Juan, Manel; Yagüe, Jordi; Mahlaoui, Nizar; Donadieu, Jean; Chen, Kang; Cerutti, Andrea

    2011-01-01

    Neutrophils utilize immunoglobulins (Igs) to clear antigen, but their role in Ig production is unknown. Here we identified neutrophils around the marginal zone (MZ) of the spleen, a B cell area specialized in T-independent Ig responses to circulating antigen. Neutrophils colonized peri-MZ areas after post-natal mucosal colonization by microbes and enhanced their B-helper function upon receiving reprogramming signals from splenic sinusoidal endothelial cells, including interleukin 10 (IL-10). Splenic neutrophils induced Ig class switching, somatic hypermutation and antibody production by activating MZ B cells through a mechanism involving the cytokines BAFF, APRIL and IL-21. Neutropenic patients had fewer and hypomutated MZ B cells and less preimmune Igs to T-independent antigens, which indicates that neutrophils generate an innate layer of antimicrobial Ig defense by interacting with MZ B cells. PMID:22197976

  12. Helper-Dependent Adenoviral Vectors and Their Use for Neuroscience Applications.

    PubMed

    Montesinos, Mónica S; Satterfield, Rachel; Young, Samuel M

    2016-01-01

    Neuroscience research has been revolutionized by the use of recombinant viral vector technology from the basic, preclinical and clinical levels. Currently, multiple recombinant viral vector types are employed with each having its strengths and weaknesses depending on the proposed application. Helper-dependent adenoviral vectors (HdAd) are emerging as ideal viral vectors that solve a major need in the neuroscience field: (1) expression of transgenes that are too large to be packaged by other viral vectors and (2) rapid onset of transgene expression in the absence of cytotoxicity. Here, we describe the methods for large-scale production of HdAd viral vectors for in vivo use with neurospecific transgene expression. PMID:27515075

  13. Analysis of the autoproteolytic activity of the recombinant helper component proteinase from zucchini yellow mosaic virus.

    PubMed

    Boonrod, Kajohn; Füllgrabe, Marc W; Krczal, Gabi; Wassenegger, Michael

    2011-10-01

    The multifunctional helper component proteinase (HC-Pro) of potyviruses contains an autoproteolytic function that, together with the protein 1 (P1) and NIa proteinase, processes the polyprotein into mature proteins. In this study, we analysed the autoproteolytic active domain of zucchini yellow mosaic virus (ZYMV) HC-Pro. Several Escherichia coli-expressed MBP:HC-Pro:GFP mutants containing deletions or point mutations at either the N- or C-terminus of the HC-Pro protein were examined. Our results showed that amino acids essential for the proteolytic activity of ZYMV HC-Pro are distinct from those of the tobacco etch virus HC-Pro, although the amino acid sequences in the proteolytic active domain are conserved among potyviruses.

  14. The CD46 and Jagged1 interaction is critical for human T helper 1 immunity

    PubMed Central

    Le Friec, Gaëlle; Sheppard, Devon; Whiteman, Pat; Karsten, Christian M.; Shamoun, Salley Al-Tilib; Laing, Adam; Bugeon, Laurence; Dallman, Margaret J.; Melchionna, Teresa; Chillakuri, Chandramouli; Smith, Richard A.; Drouet, Christian; Couzi, Lionel; Fremeaux-Bacchi, Veronique; Köhl, Jörg; Waddington, Simon N.; McDonnell, James M.; Baker, Alastair; Handford, Penny A.; Lea, Susan M.; Kemper, Claudia

    2012-01-01

    CD46 is a complement regulator with important immune-related roles. CD46 functions as a pathogen receptor and is a potent co-stimulator for the induction of interferon-γ (IFN-γ)-secreting T helper 1 (TH1) effector T cells and their subsequent switch into interleukin-10 (IL-10)-producing regulatory T cells. Here, we identify the Notch protein family member Jagged1 as a new physiological ligand for CD46. Further, CD46 regulates Notch receptors and ligands expression during T cell activation and disturbance of the CD46-Notch crosstalk impedes IFN-γ induction and IL-10 switching. Importantly, CD4+ T cells from CD46-deficient patients and patients with hypomorphic Jagged1 mutations (Alagille Syndrome) fail to mount appropriate TH1 responses in vitro and in vivo suggesting that CD46-Jagged1 crosstalk is responsible for the recurrent infections in subpopulations of these patients. PMID:23086448

  15. Filling in the helper-gap: the intentions of frail older widows.

    PubMed

    Porter, Eileen J; Ganong, Lawrence H

    2005-01-01

    Despite marked interest in continuity of care and transitions experienced by older persons, there is little information available about the intentions of older women regarding changes that occur in their support networks. This article reports the findings of a descriptive phenomenological study of older widows' experience of home care and describes the experiences of 10 women who lost a key helper during the 3-year study. Compared with theories of continuity of care or transition, the findings are in keeping with the focus of nonequilibrium systems theory: bringing order out of disorder. Findings imply the need for holistic nursing interventions with older women who hope to continue living alone for as long as possible.

  16. Bypass of carrier-induced epitope-specific suppression using a T-helper epitope.

    PubMed Central

    Sad, S; Rao, K; Arora, R; Talwar, G P; Raghupathy, R

    1992-01-01

    A gonadotropin-releasing hormone (GnRH)-based vaccine is being developed as a method for non-surgical immunotherapy as immunization with this vaccine results in atrophy of the prostate. This vaccine, a conjugate of GnRH and diphtheria toxoid (DT), provides a unique hapten-carrier system for investigating the influence of carrier presensitization on antibody responses to self haptens. In a recent communication we showed that preimmunization with carriers diphtheria toxoid and tetanus toxoid results in a strain-dependent inhibition of anti-GnRH responses in mice and that T cells from carrier-presensitized mice are responsible for anti-haptenic suppression. In the present report we describe a strategy for bypassing DT-induced epitopic suppression using a T-helper epitope from DT. PMID:1383134

  17. Altered Memory Circulating T Follicular Helper-B Cell Interaction in Early Acute HIV Infection

    PubMed Central

    Muir, Roshell; Metcalf, Talibah; Tardif, Virginie; Takata, Hiroshi; Phanuphak, Nittaya; Kroon, Eugene; Colby, Donn J.; Trichavaroj, Rapee; Valcour, Victor; Robb, Merlin L.; Michael, Nelson L.; Ananworanich, Jintanat; Trautmann, Lydie; Haddad, Elias K.

    2016-01-01

    The RV254 cohort of HIV-infected very early acute (4thG stage 1 and 2) (stage 1/2) and late acute (4thG stage 3) (stage 3) individuals was used to study T helper- B cell responses in acute HIV infection and the impact of early antiretroviral treatment (ART) on T and B cell function. To investigate this, the function of circulating T follicular helper cells (cTfh) from this cohort was examined, and cTfh and memory B cell populations were phenotyped. Impaired cTfh cell function was observed in individuals treated in stage 3 when compared to stage 1/2. The cTfh/B cell cocultures showed lower B cell survival and IgG secretion at stage 3 compared to stage 1/2. This coincided with lower IL-10 and increased RANTES and TNF-α suggesting a role for inflammation in altering cTfh and B cell responses. Elevated plasma viral load in stage 3 was found to correlate with decreased cTfh-mediated B cell IgG production indicating a role for increased viremia in cTfh impairment and dysfunctional humoral response. Phenotypic perturbations were also evident in the mature B cell compartment, most notably a decrease in resting memory B cells in stage 3 compared to stage 1/2, coinciding with higher viremia. Our coculture assay also suggested that intrinsic memory B cell defects could contribute to the impaired response despite at a lower level. Overall, cTfh-mediated B cell responses are significantly altered in stage 3 compared to stage 1/2, coinciding with increased inflammation and a reduction in memory B cells. These data suggest that early ART for acutely HIV infected individuals could prevent immune dysregulation while preserving cTfh function and B cell memory. PMID:27463374

  18. Differentiation of human B lymphocyte subpopulations induced by an alloreactive helper T-cell clone

    SciTech Connect

    Anderson, S.J.; Hummell, D.S.; Lawton, A.R.

    1988-07-01

    We have used cloned alloreactive helper T cells to determine if direct T cell-B cell interaction can induce differentiation of human peripheral blood B cells which do not respond to pokeweed mitogen (PWM). T-cell clone 2F8 was derived from a one-way mixed lymphocyte reaction. 2F8 cells are T3+T4+T8-IL-2R+ and proliferate in response to irradiated stimulator cells, but not autologous cells, in the absence of exogenous interleukin-2. 2F8 cells provide allospecific help for polyclonal proliferation and differentiation of B cells in the absence of any other stimulus. The magnitude of this response is comparable to that of the response of the same B cells to PWM and fresh autologous T cells. 2F8 cells could also provide nonspecific help for unrelated donor B cells in the presence of PWM, with no requirement for costimulation by irradiated stimulator cells. Allospecific stimulation of B cells was completely inhibited by antibodies to class II major histocompatibility complex (MHC) framework determinants and was abrogated by 1000-rad irradiation. Cloned 2F8 T cells stimulated differentiation of both small, high-density B cells and larger B cells, generating up to 30% plasma cells with either fraction. B cells forming rosettes with mouse erythrocytes were also induced to differentiate by the helper T cell clone. As found previously, neither small, high-density B cells nor mouse rosette+ B cells responded well to PWM. Direct interaction with allospecific T cells induces differentiation of a broader spectrum of B cells than soluble growth and differentiation factors in conjunction with polyclonal activators such as PWM and protein A containing staphylococci.

  19. Identification of promiscuous HPV16-derived T helper cell epitopes for therapeutic HPV vaccine design.

    PubMed

    Grabowska, Agnieszka K; Kaufmann, Andreas M; Riemer, Angelika B

    2015-01-01

    Cervical carcinoma and several other human papillomavirus (HPV)-induced malignancies are a global public health problem, thus novel treatment modalities are urgently needed. Immunotherapy is an attractive option for treatment of HPV infection and HPV-mediated premalignant and malignant lesions. However, previous approaches--focusing on the induction of cytotoxic CD8+ T cells (CTLs)--have as yet not yielded clinical successes. Since CD4+ T cells have been shown to be crucial for the induction and maintenance of CTL responses, and more recently to be also important for direct anti-tumor immunity, human leukocyte antigen (HLA) class II-restricted epitopes are intensively investigated to improve the efficacy of peptide-based HPV immunotherapy. We here present an approach to identify promiscuous HPV16-derived CD4+ T helper epitopes, which are capable of inducing T cell immunity in a large proportion of the population. To this end, we combined HLA class II epitope prediction servers with in vitro immunological evaluation to identify HPV16 E2-, E5-, E6-, and E7-derived CD4+ T cell epitopes. Candidate selected HPV16-derived epitopes were found to be restricted by up to nine HLA-DR molecules. Furthermore, they were found to induce frequent and robust HPV16 peptide-specific Th1 responses in healthy donors, as monitored by interferon (IFN)-γ ELISPOT and cytokine secretion assays. Moreover, these selected peptides also induced specific IFN-γ T cell responses in blood from HPV16+ CIN2/3 and cervical carcinoma patients. We thus conclude that the identified T helper epitopes are valuable candidates for the development of a comprehensive therapeutic HPV vaccine.

  20. Abnormalities of follicular helper T-cell number and function in Wiskott-Aldrich syndrome

    PubMed Central

    Zhang, Xuan; Dai, Rongxin; Li, Wenyan; Zhao, Hongyi; Zhang, Yongjie; Zhou, Lina; Du, Hongqiang; Luo, Guangjin; Wu, Junfeng; Niu, Linlin; An, Yunfei; Zhang, Zhiyong; Ding, Yuan; Song, Wenxia; Liu, Chaohong

    2016-01-01

    Wiskott-Aldrich syndrome protein (WASp) is a hematopoietic-specific regulator of actin nucleation. Wiskott-Aldrich syndrome (WAS) patients show immunodeficiencies, most of which have been attributed to defective T-cell functions. T follicular helper (Tfh) cells are the major CD4+ T-cell subset with specialized B-cell helper capabilities. Aberrant Tfh cells activities are involved in immunopathologies such as autoimmunity, immunodeficiencies, and lymphomas. We found that in WAS patients, the number of circulating Tfh cells was significantly reduced due to reduced proliferation and increased apoptosis, and Tfh cells were Th2 and Th17 polarized. The expression of inducible costimulator (ICOS) in circulating Tfh cells was higher in WAS patients than in controls. BCL6 expression was decreased in total CD4+ T and Tfh cells of WAS patients. Mirroring the results in patients, the frequency of Tfh cells in WAS knockout (KO) mice was decreased, as was the frequency of BCL6+ Tfh cells, but the frequency of ICOS+ Tfh cells was increased. Using WAS chimera mice, we found that the number of ICOS+ Tfh cells was decreased in WAS chimera mice, indicating that the increase in ICOS+ Tfh cells in WAS KO mice was cell extrinsic. The data from in vivo CD4+ naive T-cell adoptive transfer mice as well as in vitro coculture of naive B and Tfh cells showed that the defective function of WASp-deficient Tfh cells was T-cell intrinsic. Consistent findings in both WAS patients and WAS KO mice suggested an essential role for WASp in the development and memory response of Tfh cells and that WASp deficiency causes a deficient differentiation defect in Tfh cells by downregulating the transcription level of BCL6. PMID:27170596

  1. Mathematical model for HIV dynamics in HIV-specific helper cells

    NASA Astrophysics Data System (ADS)

    Pinto, Carla M. A.; Carvalho, Ana

    2014-03-01

    In this paper we study a delay mathematical model for the dynamics of HIV in HIV-specific CD4 + T helper cells. We modify the model presented by Roy and Wodarz in 2012, where the HIV dynamics is studied, considering a single CD4 + T cell population. Non-specific helper cells are included as alternative target cell population, to account for macrophages and dendritic cells. In this paper, we include two types of delay: (1) a latent period between the time target cells are contacted by the virus particles and the time the virions enter the cells and; (2) virus production period for new virions to be produced within and released from the infected cells. We compute the reproduction number of the model, R0, and the local stability of the disease free equilibrium and of the endemic equilibrium. We find that for values of R0<1, the model approaches asymptotically the disease free equilibrium. For values of R0>1, the model approximates asymptotically the endemic equilibrium. We observe numerically the phenomenon of backward bifurcation for values of R0⪅1. This statement will be proved in future work. We also vary the values of the latent period and the production period of infected cells and free virus. We conclude that increasing these values translates in a decrease of the reproduction number. Thus, a good strategy to control the HIV virus should focus on drugs to prolong the latent period and/or slow down the virus production. These results suggest that the model is mathematically and epidemiologically well-posed.

  2. Determinants of job satisfaction in foreign domestic helpers caring for people with dementia in Hong Kong.

    PubMed

    Bai, Xue; Kwok, Timothy C Y; Chan, Natalie Y T; Ho, Florence K Y

    2013-09-01

    The job satisfaction of live-in foreign domestic helpers (FDHs) may influence their caring motivation and the quality of care they provide, which may in turn affect the health status of care recipients. This study identifies the factors affecting job satisfaction of FDHs caring for people with dementia in Hong Kong, focusing especially on the role of FDHs' adaptation status, job self-efficacy and care recipients' situation. A total of 152 FDHs taking care of people with dementia were recruited from 6 day care centres for elderly people in Hong Kong when they attended with their care recipients. Data were collected from February to August 2011 and the response rate was 95%. Participants completed questionnaires which included measures of care recipients' dementia severity and disruptive behaviours, FDHs' demographic factors, personal adaptation status, caregiving self-efficacy and job satisfaction. Hierarchical regression analysis was conducted to analyse the data. The results showed that longer stay in Hong Kong, better fluency in Cantonese (local dialect), greater satisfaction in living conditions, higher caregiving self-efficacy and less disruptive behaviour of care recipients were independently associated with stronger job satisfaction in FDHs looking after people with dementia. On the basis of these findings, we would suggest that employers should consider helpers who have been in Hong Kong for a longer period of time and speak fluent Cantonese, and have previous experience of taking care of people with dementia. In addition, FDHs caring for people with dementia may benefit from carer training which improves their self-efficacy in dementia care. PMID:23496204

  3. Decreased PD-1 positive blood follicular helper T cells in patients with psoriasis.

    PubMed

    Shin, Dongyun; Kim, Dae Suk; Kim, Sung Hee; Je, Jung Hwan; Kim, Hee Ju; Young Kim, Do; Kim, Soo Min; Lee, Min-Geol

    2016-10-01

    Follicular helper T (Tfh) cells are recently characterized subset of helper T cells, which are initially found in the germinal centers of B cell follicles. The major role of Tfh cells is helping B cell activation and antibody production during humoral immunity. Recently, blood Tfh cells were shown to be associated with autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis, bullous pemphigoid and psoriasis. There is only one study which investigated Tfh cells in psoriasis patients. Therefore, in this study, we evaluated and analyzed blood Tfh cells in Korean patients with psoriasis. A total of 28 psoriasis patients and 16 healthy controls were enrolled. The frequency and absolute number of CXCR5(+)PD-1(+) Tfh cells were decreased in patients with psoriasis compared to healthy controls. CD4(+)CXCR5(+) T cells and CXCR5(+)ICOS(+) Tfh cells did not show differences. The frequency and absolute number of CXCR5(+)PD-1(+) Tfh cells in psoriasis patients negatively correlated with erythrocyte sedimentation rate and positively correlated with disease duration. The absolute number of CXCR5(+)ICOS(+) Tfh cells also showed positive correlation with disease duration. However, the subpopulations of Tfh cells did not correlate with Psoriasis Area and Severity Index. Serum interleukin-21 level was significantly increased in psoriasis patients compared to healthy controls, however, its level did not correlate with clinical and experimental parameters of psoriasis patients. These findings suggest the decreased function of Tfh cells in psoriasis, which could result in attenuated B cell immune responses in the pathogenesis of psoriasis. However, further investigations are necessary to confirm the function of Tfh cells in psoriasis vulgaris. PMID:27501809

  4. Impact of adenovirus life cycle progression on the generation of canine helper-dependent vectors.

    PubMed

    Fernandes, P; Simão, D; Guerreiro, M R; Kremer, E J; Coroadinha, A S; Alves, P M

    2015-01-01

    Helper-dependent adenovirus vectors (HDVs) are safe and efficient tools for gene transfer with high cloning capacity. However, the multiple amplification steps needed to produce HDVs hamper a robust production process and in turn the availability of high-quality vectors. To understand the factors behind the low productivity, we analyzed the progression of HDV life cycle. Canine adenovirus (Ad) type 2 vectors, holding attractive features to overcome immunogenic concerns and treat neurobiological disorders, were the focus of this work. When compared with E1-deleted (ΔE1) vectors, we found a faster helper genome replication during HDV production. This was consistent with an upregulation of the Ad polymerase and pre-terminal protein and led to higher and earlier expression of structural proteins. Although genome packaging occurred similarly to ΔE1 vectors, more immature capsids were obtained during HDV production, which led to a ~4-fold increase in physical-to-infectious particles ratio. The higher viral protein content in HDV-producing cells was also consistent with an increased activation of autophagy and cell death, in which earlier cell death compromised volumetric productivity. The increased empty capsids and earlier cell death found in HDV production may partially contribute to the lower vector infectivity. However, an HDV-specific factor responsible for a defective maturation process should be also involved to fully explain the low infectious titers. This study showed how a deregulated Ad cycle progression affected cell line homeostasis and HDV propagation, highlighting the impact of vector genome design on virus-cell interaction.

  5. Interleukin-32 is progressively expressed in Mycosis Fungoides independent of helper T-cell 2 and helper T-cell 9 polarization

    PubMed Central

    Ohmatsu, Hanako; Humme, Daniel; Gulati, Nicholas; Gonzalez, Juana; Möbs, Markus; Suárez-Fariñas, Mayte; Cardinale, Irma; Mitsui, Hiroshi; Guttman-Yassky, Emma; Sterry, Wolfram; Krueger, James G.

    2014-01-01

    Mycosis Fungoides (MF), the most common type of cutaneous T-cell lymphoma (CTCL) is characterized by a helper T cell 2 (Th2)-skewing with a mature CD4+ memory T-cell phenotype. Using skin samples from MF patients (n=21), healthy volunteers (n=17), individuals with atopic dermatitis (n=17) and psoriasis (n=9), we found interleukin (IL)-32 mRNA expression significantly higher in MF samples than in samples from benign inflammatory skin diseases, and its expression increases with disease progression. By immunohistochemistry and immunofluorescence, we confirmed IL-32 protein expression in many CD3+CD4+ T cells and some epidermotropic T cells in MF lesions. MyLa cells (a MF cell line) express IL-32, which in turn could promote cellular proliferation and viability in a dose-dependent fashion. IL-32-treated MyLa and CTCL HH cells up-regulated cell proliferation and survival genes. Of the major “polarizing” T-cell cytokines, only IFNγ mRNA increases with MF progression and positively correlates with IL-32 mRNA expression. Th2 cytokines do not positively correlate with IL-32 mRNA expression or MF progression. Furthermore, by flow cytometry, IL-32 production by circulating activated T-cells in healthy individuals was found in both IFNγ+ and IFNγ− cells but not in IL-4+ or IL-13+ cells. In conclusion, we have identified IL-32+ cells as the likely tumor cells in MF, and demonstrated that IL-32 mRNA expression increases with MF progression and is significantly higher than those in other skin diseases, and that some IL-32+ T cells are independent from the defined Th subsets. Thus IL-32 may play a unique role in MF progression as an autocrine cytokine. PMID:24938282

  6. IL32 is progressively expressed in mycosis fungoides independent of helper T-cell 2 and helper T-cell 9 polarization.

    PubMed

    Ohmatsu, Hanako; Humme, Daniel; Gulati, Nicholas; Gonzalez, Juana; Möbs, Markus; Suárez-Fariñas, Mayte; Cardinale, Irma; Mitsui, Hiroshi; Guttman-Yassky, Emma; Sterry, Wolfram; Krueger, James G

    2014-09-01

    Mycosis fungoides, the most common type of cutaneous T-cell lymphoma (CTCL), is characterized by a helper T-cell 2 (Th2) skewing with a mature CD4(+) memory T-cell phenotype. Using skin samples from patients with mycosis fungoides (n = 21), healthy volunteers (n = 17), and individuals with atopic dermatitis (n = 17) and psoriasis (n = 9), we found IL32 mRNA expression significantly higher in mycosis fungoides samples than in samples from benign inflammatory skin diseases, and its expression increases with disease progression. By IHC and immunofluorescence, we confirmed IL32 protein expression in many CD3(+)CD4(+) T cells and some epidermotropic T cells in mycosis fungoides lesions. MyLa cells (a mycosis fungoides cell line) express IL32, which, in turn, could promote cellular proliferation and viability in a dose-dependent fashion. IL32-treated MyLa and CTCL HH cells upregulated cell proliferation and survival genes. Of the major "polarizing" T-cell cytokines, only IFNγ mRNA increases with mycosis fungoides progression and positively correlates with IL32 mRNA expression. Th2 cytokines do not positively correlate with IL32 mRNA expression or mycosis fungoides progression. Furthermore, by flow cytometry, IL32 production by circulating activated T cells in healthy individuals was found in both IFNγ(+) and IFNγ(-) cells but not in IL4(+) or IL13(+) cells. In conclusion, we have identified IL32(+) cells as the likely tumor cells in mycosis fungoides, and demonstrated that IL32 mRNA expression increases with mycosis fungoides progression and is significantly higher than mRNA expression in other skin diseases, and that some IL32(+) T cells are independent from the defined Th subsets. Thus, IL32 may play a unique role in mycosis fungoides progression as an autocrine cytokine.

  7. Females increase reproductive investment in response to helper-mediated improvements in allo-feeding, nest survival, nestling provisioning and post-fledging survival in the Karoo scrub-robin Cercotrichas coryphaeus

    USGS Publications Warehouse

    Lloyd, P.; Andrew, Taylor W.; Du Plessis, M.A.; Martin, T.E.

    2009-01-01

    In many cooperatively-breeding species, the presence of one or more helpers improves the reproductive performance of the breeding pair receiving help. Helper contributions can take many different forms, including allo-feeding, offspring provisioning, and offspring guarding or defence. Yet, most studies have focussed on single forms of helper contribution, particularly offspring provisioning, and few have evaluated the relative importance of a broader range of helper contributions to group reproductive performance. We examined helper contributions to multiple components of breeding performance in the Karoo scrub-robin Cercotrichas coryphaeus, a facultative cooperative breeder. We also tested a prediction of increased female investment in reproduction when helpers improve conditions for rearing young. Helpers assisted the breeding male in allo-feeding the incubating female, increasing allo-feeding rates. Greater allo-feeding correlated with greater female nest attentiveness during incubation. Nest predation was substantially lower among pairs breeding with a helper, resulting in a 74% increase in the probability of nest survival. Helper contributions to offspring provisioning increased nestling feeding rates, resulting in a reduced incidence of nestling starvation and increased nestling mass. Nestling mass had a strong, positive effect on post-fledging survival. Controlling for female age and habitat effects, annual production of fledged young was 130% greater among pairs breeding with a helper, and was influenced most strongly by helper correlates with nest survival, despite important helper effects on offspring provisioning. Females breeding with a helper increased clutch size, supporting the prediction of increased female investment in reproduction in response to helper benefits. ?? 2009 J. Avian Biol.

  8. The B cell repertoire revealed by major histocompatibility complex- specific helper T cells. I. Frequencies of a genetically defined V region marker among mitogen- and T helper cell-reactive B lymphocytes in normal and immunized mice

    PubMed Central

    1984-01-01

    The aim of the present work was to analyze the frequencies of a genetically defined variable (V) region marker in the B cell subset sensitive to T cell help. To this end we used an alloreactive T cell line that has the property of inducing B cells of the appropriate haplotype to exponential growth and polyclonal antibody synthesis. The frequency obtained with this helper line was also directly compared to that obtained with lipopolysaccharide (LPS). We found that in normal BALB/c mice the frequency of M460-positive clonotypes was respectively, 1/100 and 1/1,000 among the T helper- and LPS-sensitive B cell subsets. In mice immunized with antiidiotype coupled to a thymus-dependent antigen, the differences in the numbers of idiotype-positive precursors were even more accentuated, i.e. 1/20 in the B cell subset triggered by T helper cells and 1/800 in those cells responsive to LPS. The frequencies of the M460 determinant in mice immunized with anti- idiotypes coupled to thymus-independent antigens were not significantly different, in either B cell subset, from those obtained with spleen cells of normal nonimmunized animals. Taken as a whole, our results imply that the V gene repertoire revealed by LPS includes precursor distribution, as this distribution occurs during the early stage of B cell development (potential repertoire), while the repertoire revealed by T helper cells includes the V region distribution of those clones that are selected in the periphery of the functional immune system. PMID:6200567

  9. The positive bystander effect: passive bystanders increase helping in situations with high expected negative consequences for the helper.

    PubMed

    Fischer, Peter; Greitemeyer, Tobias

    2013-01-01

    The present field study investigated the interplay between the presence of a passive bystander (not present versus present) in a simulated bike theft and expected negative consequences (low versus high) in predicting intervention behavior when no physical victim is present. It was found that an additional bystander increases individual intervention in situations where the expected negative consequences for the helper in case of intervention were high (i.e., when the bike thief looks fierce) compared to situations where the expected negative consequences for the helper were low (i.e., when the bike thief does not look fierce). In contrast, no such effect for high vs. low expected negative consequences was observed when no additional bystander observed the critical situation. The results are discussed in light of previous laboratory findings on expected negative consequences and bystander intervention. PMID:23421000

  10. Independence, Security, and the intergenerational social contract: home-helper services and elder care in rural Japan.

    PubMed

    Traphagan, John W

    2003-01-01

    For several years, demographic trends and changing ideas about responsibilities for elder care in Japan have contributed to the desire, or need, for families to seek out new care approaches. This article focuses on one alternative to traditional approaches to caring for elder family members--the home-helper program that is available through the Japanese long-term care insurance program. Using ethnographic data collected in northern Japan, it will be argued that the home-helper program forms a compensatory elder care system that is intended to augment family-provided care and social support, rather than to promote independent living. This compensatory approach to elder care is based upon an intergenerational social contract in which it is assumed that some degree of dependence on family members is both an expected and preferred outcome of growing old.

  11. Regulation of DNA methylation dictates Cd4 expression during the development of helper and cytotoxic T cell lineages.

    PubMed

    Sellars, MacLean; Huh, Jun R; Day, Kenneth; Issuree, Priya D; Galan, Carolina; Gobeil, Stephane; Absher, Devin; Green, Michael R; Littman, Dan R

    2015-07-01

    During development, progenitor cells with binary potential give rise to daughter cells that have distinct functions. Heritable epigenetic mechanisms then lock in gene-expression programs that define lineage identity. Regulation of the gene encoding the T cell-specific coreceptor CD4 in helper and cytotoxic T cells exemplifies this process, with enhancer- and silencer-regulated establishment of epigenetic memory for stable gene expression and repression, respectively. Using a genetic screen, we identified the DNA-methylation machinery as essential for maintaining silencing of Cd4 in the cytotoxic lineage. Furthermore, we found a requirement for the proximal enhancer in mediating the removal of DNA-methylation marks from Cd4, which allowed stable expression of Cd4 in helper T cells. Our findings suggest that stage-specific methylation and demethylation events in Cd4 regulate its heritable expression in response to the distinct signals that dictate lineage 'choice' during T cell development. PMID:26030024

  12. Probing the Strength of Infants' Preference for Helpers over Hinderers: Two Replication Attempts of Hamlin and Wynn (2011).

    PubMed

    Salvadori, Eliala; Blazsekova, Tatiana; Volein, Agnes; Karap, Zsuzsanna; Tatone, Denis; Mascaro, Olivier; Csibra, Gergely

    2015-01-01

    Several studies indicate that infants prefer individuals who act prosocially over those who act antisocially toward unrelated third parties. In the present study, we focused on a paradigm published by Kiley Hamlin and Karen Wynn in 2011. In this study, infants were habituated to a live puppet show in which a protagonist tried to open a box to retrieve a toy placed inside. The protagonist was either helped by a second puppet (the "Helper"), or hindered by a third puppet (the "Hinderer"). At test, infants were presented with the Helper and the Hinderer, and encouraged to reach for one of them. In the original study, 75% of 9-month-olds selected the Helper, arguably demonstrating a preference for prosocial over antisocial individuals. We conducted two studies with the aim of replicating this result. Each attempt was performed by a different group of experimenters. Study 1 followed the methods of the published study as faithfully as possible. Study 2 introduced slight modifications to the stimuli and the procedure following the guidelines generously provided by Kiley Hamlin and her collaborators. Yet, in our replication attempts, 9-month-olds' preference for helpers over hinderers did not differ significantly from chance (62.5% and 50%, respectively, in Studies 1 and 2). Two types of factors could explain why our results differed from those of Hamlin and Wynn: minor methodological dissimilarities (in procedure, materials, or the population tested), or the effect size being smaller than originally assumed. We conclude that fine methodological details that are crucial to infants' success in this task need to be identified to ensure the replicability of the original result. PMID:26565412

  13. Location and Survival of Mycorrhiza Helper Pseudomonas fluorescens during Establishment of Ectomycorrhizal Symbiosis between Laccaria bicolor and Douglas Fir

    PubMed Central

    Frey-Klett, P.; Pierrat, J. C.; Garbaye, J.

    1997-01-01

    The mycorrhiza helper bacterium Pseudomonas fluorescens BBc6, isolated from a Laccaria bicolor sporocarp, consistently promotes L. bicolor-Douglas fir (Pseudotsuga menziesii) ectomycorrhizal formation, even with low doses of bacterial inoculum. In order to describe this phenomenon more accurately, we have looked at the location and survival of the introduced bacterial strain in the soil and in the rhizosphere during the establishment of mycorrhizal symbiosis in glasshouse and nursery experiments. Bacterial populations were quantified with a spontaneous, stable, rifampin-resistant mutant, BBc6R8, which phenotypically conformed to the parental strain. BBc6R8 populations declined rapidly, reaching the detection limit after 19 weeks, and did not increase either when L. bicolor sporocarps were forming in autumn or when Douglas fir roots resumed growing in spring. BBc6R8 was neither an endophyte nor a rhizobacterium. Furthermore, it was not particularly associated with either mycorrhizas of Douglas fir-L. bicolor or L. bicolor sporocarps. Surprisingly, a significant mycorrhiza helper effect was observed when the inoculated BBc6R8 population had dropped as low as 30 CFU g of dry matter(sup-1) in the soil. This study raises questions concerning the bacterial concentration in the soil which is effective for promotion of mycorrhizal establishment and the timing of the bacterial effect. It allows us to develop working hypotheses, which can be tested experimentally, to identify the mechanisms of the mycorrhiza helper effect. PMID:16535478

  14. Mycorrhization between Cistus ladanifer L. and Boletus edulis Bull is enhanced by the mycorrhiza helper bacteria Pseudomonas fluorescens Migula.

    PubMed

    Mediavilla, Olaya; Olaizola, Jaime; Santos-del-Blanco, Luis; Oria-de-Rueda, Juan Andrés; Martín-Pinto, Pablo

    2016-02-01

    Boletus edulis Bull. is one of the most economically and gastronomically valuable fungi worldwide. Sporocarp production normally occurs when symbiotically associated with a number of tree species in stands over 40 years old, but it has also been reported in 3-year-old Cistus ladanifer L. shrubs. Efforts toward the domestication of B. edulis have thus focused on successfully generating C. ladanifer seedlings associated with B. edulis under controlled conditions. Microorganisms have an important role mediating mycorrhizal symbiosis, such as some bacteria species which enhance mycorrhiza formation (mycorrhiza helper bacteria). Thus, in this study, we explored the effect that mycorrhiza helper bacteria have on the efficiency and intensity of the ectomycorrhizal symbiosis between C. ladanifer and B. edulis. The aim of this work was to optimize an in vitro protocol for the mycorrhizal synthesis of B. edulis with C. ladanifer by testing the effects of fungal culture time and coinoculation with the helper bacteria Pseudomonas fluorescens Migula. The results confirmed successful mycorrhizal synthesis between C. ladanifer and B. edulis. Coinoculation of B. edulis with P. fluorescens doubled within-plant mycorrhization levels although it did not result in an increased number of seedlings colonized with B. edulis mycorrhizae. B. edulis mycelium culture time also increased mycorrhization levels but not the presence of mycorrhizae. These findings bring us closer to controlled B. edulis sporocarp production in plantations.

  15. Mycorrhization between Cistus ladanifer L. and Boletus edulis Bull is enhanced by the mycorrhiza helper bacteria Pseudomonas fluorescens Migula.

    PubMed

    Mediavilla, Olaya; Olaizola, Jaime; Santos-del-Blanco, Luis; Oria-de-Rueda, Juan Andrés; Martín-Pinto, Pablo

    2016-02-01

    Boletus edulis Bull. is one of the most economically and gastronomically valuable fungi worldwide. Sporocarp production normally occurs when symbiotically associated with a number of tree species in stands over 40 years old, but it has also been reported in 3-year-old Cistus ladanifer L. shrubs. Efforts toward the domestication of B. edulis have thus focused on successfully generating C. ladanifer seedlings associated with B. edulis under controlled conditions. Microorganisms have an important role mediating mycorrhizal symbiosis, such as some bacteria species which enhance mycorrhiza formation (mycorrhiza helper bacteria). Thus, in this study, we explored the effect that mycorrhiza helper bacteria have on the efficiency and intensity of the ectomycorrhizal symbiosis between C. ladanifer and B. edulis. The aim of this work was to optimize an in vitro protocol for the mycorrhizal synthesis of B. edulis with C. ladanifer by testing the effects of fungal culture time and coinoculation with the helper bacteria Pseudomonas fluorescens Migula. The results confirmed successful mycorrhizal synthesis between C. ladanifer and B. edulis. Coinoculation of B. edulis with P. fluorescens doubled within-plant mycorrhization levels although it did not result in an increased number of seedlings colonized with B. edulis mycorrhizae. B. edulis mycelium culture time also increased mycorrhization levels but not the presence of mycorrhizae. These findings bring us closer to controlled B. edulis sporocarp production in plantations. PMID:26208816

  16. Opposite effects of male and female helpers on social tolerance and proactive prosociality in callitrichid family groups

    PubMed Central

    Burkart, Judith M.

    2015-01-01

    Across a broad variety of primate species (including lemurs, New World monkeys, Old World monkeys, and apes), proactive prosociality and social tolerance are linked to allomaternal care, reaching the highest levels in the cooperatively breeding callitrichid monkeys and humans. However, considerable variation exists within callitrichids, and the aim of this study was to identify factors that explain this variation. Male and female callitrichids pursue different reproductive strategies, leading males to play a more prominent role in allomothering. We thus hypothesised that prosociality and tolerance may be affected by group composition and sex differences. We analysed social tolerance and proactive prosociality data in 49 common marmosets and found that the number of female helpers in a group was negatively correlated with group-level prosociality and tolerance. At the individual level, rearing experience or age enhanced prosociality in male, but not in female helpers. These findings are consistent with the more ambivalent role of female helpers in infant rearing. Adding data from 5 cotton-top and 5 lion tamarins strengthened this pattern. The same factor which explains variation in prosociality and tolerance across primate species, i.e. allomaternal care, is therefore also linked to variation within common marmosets, and presumably callitrichid monkeys in general. PMID:25881136

  17. Functional expression of CD137 (4-1BB) on T helper follicular cells

    PubMed Central

    Alfaro, Carlos; Echeveste, Jose I; Rodriguez-Ruiz, Maria E; Solorzano, Jose L; Perez-Gracia, Jose L; Idoate, Miguel A; Lopez-Picazo, Jose M; Sanchez-Paulete, Alfonso R; Labiano, Sara; Rouzaut, Ana; Oñate, Carmen; Aznar, Angela; Lozano, Maria D; Melero, Ignacio

    2015-01-01

    CD137 (4-1BB) is a surface protein initially discovered to mark activated T lymphocytes. However, its broader expression pattern also encompasses activated NK cells, B cells and myeloid cells, including mature dendritic cells. In this study, we have immunostained for CD137 on paraffin-embedded lymphoid tissues including tonsils, lymph nodes, ectopic tertiary lymphoid tissue in Hashimoto thyroiditis and cancer. Surprisingly, immunostaining mainly decorated intrafollicular lymphocytes in the tissues analyzed, with only scattered staining in interfollicular areas. Moreover, pathologic lymphoid follicles in follicular lymphoma and tertiary lymphoid tissue associated with non-small cell lung cancer showed a similar pattern of immunostaining. Multispectral fluorescence cytometry demonstrated that CD137 expression was restricted to CD4+ CXCR5+ follicular T helper lymphocytes (TFH cells) in tonsils and lymph nodes. Short-term culture of lymph node cell suspensions in the presence of either an agonistic anti-CD137 monoclonal antibody (mAb) or CD137-ligand stimulated the functional upregulation of TFH cells in 3 out of 6 cases, as indicated by CD40L surface expression and cytokine production. As a consequence, immunostimulatory monoclonal antibodies targeting CD137 (such as urelumab and PF-05082566) should be expected to primarily act on this lymphocyte subset, thus modifying ongoing humoral immune responses in patients with autoimmune disease and cancer. PMID:26587331

  18. T helper cell polarisation as a measure of the maturation of the immune response.

    PubMed Central

    Cameron, Scott B; Stolte, Ellen H; Chow, Anthony W; Savelkoul, Huub F J

    2003-01-01

    BACKGROUND: T helper cell polarisation is important under chronic immune stimulatory conditions and drives the type of the evolving immune response. Mice treated with superantigens in vivo display strong effects on Th subset differentiation. The aim of the study was to detect the intrinsic capacity of T cells to polarise under various ex vivo conditions. METHODS: Purified CD4+ T cells obtained from super-antigen-treated mice were cultured under Th polarising conditions in vitro. By combining intracellular cytokine staining and subsequent flow cytometric analysis with quantitative cytokine measurements in culture supernatants by enzyme-linked immunosorbent assay (ELISA), the differential Th polarising capacity of the treatment can be detected in a qualitative and quantitative manner. RESULTS AND CONCLUSIONS: BALB/c mice were shown to be biased to develop strong Th2 polarised immune responses using Th0 stimulation of purified CD4+ T cells from phosphate-buffered saline-treated mice. Nevertheless, our analysis methodology convincingly showed that even in these mice, Toxic Shock Syndrome Toxin-1 treatment in vivo resulted in a significantly stronger Th1 polarising effect than control treatment. Our results indicate that populations of Th cells can be assessed individually for their differential Th1 or Th2 maturation capacity in vivo by analysing robust in vitro polarisation cultures combined with intracellular cytokine staining and ELISA. PMID:14760935

  19. The T helper type 17/regulatory T cell paradigm in pregnancy.

    PubMed

    Figueiredo, Ana Sofia; Schumacher, Anne

    2016-05-01

    T helper type 17 (Th17) and regulatory T (Treg) cells are active players in the establishment of tolerance and defence. These attributes of the immune system enmesh to guarantee the right level of protection. The healthy immune system, on the one hand, recognizes and eliminates dangerous non-self pathogens and, on the other hand, protects the healthy self. However, there are circumstances where this fine balance is disrupted. In fact, in situations such as in pregnancy, the foreign fetal antigens challenge the maternal immune system and Treg cells will dominate Th17 cells to guarantee fetal survival. In other situations such as autoimmunity, where the Th17 responses are often overwhelming, the immune system shifts towards an inflammatory profile and attacks the healthy tissue from the self. Interestingly, autoimmune patients have meliorating symptoms during pregnancy. This connects with the antagonist role of Th17 and Treg cells, and their specific profiles during these two immune challenging situations. In this review, we put into perspective the Th17/Treg ratio during pregnancy and autoimmunity, as well as in pregnant women with autoimmune conditions. We further review existing systems biology approaches that study specific mechanisms of these immune cells using mathematical modelling and we point out possible future directions of investigation. Understanding what maintains or disrupts the balance between these two opponent yet reciprocal cells in healthy physiological settings, sheds light into the development of innovative pharmacological approaches to fight pregnancy loss and autoimmunity.

  20. Treatment of osteoarthritis using a helper-dependent adenoviral vector retargeted to chondrocytes.

    PubMed

    Ruan, Merry Zc; Cerullo, Vincenzo; Cela, Racel; Clarke, Chris; Lundgren-Akerlund, Evy; Barry, Michael A; Lee, Brendan Hl

    2016-01-01

    Osteoarthritis (OA) is a joint disease characterized by degeneration of the articular cartilage, subchondral bone remodeling, and secondary inflammation. It is among the top three causes of chronic disability, and currently there are no treatment options to prevent disease progression. The localized nature of OA makes it an ideal candidate for gene and cell therapy. However, gene and cell therapy of OA is impeded by inefficient gene transduction of chondrocytes. In this study, we developed a broadly applicable system that retargets cell surface receptors by conjugating antibodies to the capsid of helper-dependent adenoviral vectors (HDVs). Specifically, we applied this system to retarget chondrocytes by conjugating an HDV to an α-10 integrin monoclonal antibody (a10mab). We show that a10mab-conjugated HDV (a10mabHDV)-infected chondrocytes efficiently in vitro and in vivo while detargeting other cell types. The therapeutic index of an intra-articular injection of 10mabHDV-expressing proteoglycan 4 (PRG4) into a murine model of post-traumatic OA was 10-fold higher than with standard HDV. Moreover, we show that PRG4 overexpression from articular, superficial zone chondrocytes is effective for chondroprotection in postinjury OA and that α-10 integrin is an effective protein for chondrocyte targeting. PMID:27626040

  1. Treatment of osteoarthritis using a helper-dependent adenoviral vector retargeted to chondrocytes

    PubMed Central

    Ruan, Merry ZC; Cerullo, Vincenzo; Cela, Racel; Clarke, Chris; Lundgren-Akerlund, Evy; Barry, Michael A; Lee, Brendan HL

    2016-01-01

    Osteoarthritis (OA) is a joint disease characterized by degeneration of the articular cartilage, subchondral bone remodeling, and secondary inflammation. It is among the top three causes of chronic disability, and currently there are no treatment options to prevent disease progression. The localized nature of OA makes it an ideal candidate for gene and cell therapy. However, gene and cell therapy of OA is impeded by inefficient gene transduction of chondrocytes. In this study, we developed a broadly applicable system that retargets cell surface receptors by conjugating antibodies to the capsid of helper-dependent adenoviral vectors (HDVs). Specifically, we applied this system to retarget chondrocytes by conjugating an HDV to an α-10 integrin monoclonal antibody (a10mab). We show that a10mab-conjugated HDV (a10mabHDV)-infected chondrocytes efficiently in vitro and in vivo while detargeting other cell types. The therapeutic index of an intra-articular injection of 10mabHDV-expressing proteoglycan 4 (PRG4) into a murine model of post-traumatic OA was 10-fold higher than with standard HDV. Moreover, we show that PRG4 overexpression from articular, superficial zone chondrocytes is effective for chondroprotection in postinjury OA and that α-10 integrin is an effective protein for chondrocyte targeting. PMID:27626040

  2. Twist1 regulates Ifng expression in T helper 1 cells by interfering with Runx3 function

    PubMed Central

    Pham, Duy; Vincentz, Joshua W.; Firulli, Anthony B.; Kaplan, Mark H.

    2012-01-01

    A transcription factor network that includes STAT4, T-bet and Runx3 promotes the differentiation of T helper type 1 (Th1) cells and inflammatory immune responses. How additional transcription factors regulate the function of Th1 cells has not been defined. In this report we show that the negative regulatory factor Twist1 decreases expression of T-bet, Runx3 and IL-12Rβ2 as it inhibits IFN-γ production. Ectopic expression of Runx3, but not T-bet or IL-12Rβ2 compensates for the effects of Twist1 on IFN-γ production, and Twist1 regulation of Ifng depends upon complex formation with Runx3. Twist1 decreases Runx3 and T-bet binding at the Ifng locus, and decreases chromatin looping within the Ifng locus. These data define an IL-12/STAT4-induced negative regulatory loop that impacts multiple components of the Th1 transcriptional network and provides further insight into regulation of Th1 differentiation. PMID:22685315

  3. Role of distinct CD4(+) T helper subset in pathogenesis of oral lichen planus.

    PubMed

    Wang, Hui; Zhang, Dunfang; Han, Qi; Zhao, Xin; Zeng, Xin; Xu, Yi; Sun, Zheng; Chen, Qianming

    2016-07-01

    Oral lichen planus (OLP) is one of the most common chronic inflammatory oral mucosal diseases with T-cell-mediated immune pathogenesis. In subepithelial and lamina propria of OLP local lesions, the presence of CD4(+) T helper (CD4(+) Th) cells appeared as the major lymphocytes. These CD4(+) T lymphocytes can differentiate into distinct Th cell types such as Th1, Th2, Treg, Th17, Th22, Th9, and Tfh within the context of certain cytokines environment. Growing evidence indicated that Th1/Th2 imbalance may greatly participate into the cytokine network of OLP immunopathology. In addition, Th1/Th2 imbalance can be regulated by the Treg subset and also greatly influenced by the emerging novel CD4(+) Th subset Th17. Furthermore, the presence of novel subsets Th22, Th9 and Tfh in OLP patients is yet to be clarified. All these Th subsets and their specific cytokines may play a critical role in determining the character, extent and duration of immune responses in OLP pathogenesis. Therefore, we review the roles of distinct CD4(+) Th subsets and their signature cytokines in determining disease severity and susceptibility of OLP and also reveal the novel therapeutic strategies based on T lymphocytes subsets in OLP treatment. PMID:26693958

  4. Robust Hepatic Gene Silencing for Functional Studies Using Helper-Dependent Adenoviral Vectors

    PubMed Central

    Ruiz, Rafaela; Witting, Scott R.; Saxena, Romil

    2009-01-01

    Abstract RNA interference is currently envisioned as the basis of gene function and drug target validation studies. This novel technology has the advantage of providing a remarkably faster tool for gene silencing than traditional transgenic animal methodologies. In vivo administration of short interfering RNA (siRNA) typically results in reduced target gene expression for approximately 1 week. Viral vectors offer the possibility to express constitutive levels of short hairpin RNA (shRNA) so that the effects of knocking down the target gene can be studied for a few weeks, rather than a few days. Helper-dependent vectors have a significant advantage over previous generations of adenoviral vectors because of their much higher cloning capacity, potential for long-term transgene expression, and enhanced safety profiles on administration in vivo. Therefore, this advanced type of vector is an excellent tool to carry out in vivo studies directed at constitutive expression of shRNA. Here we show it is possible to obtain more than 90% target gene knockdown in an animal model of type 2 diabetes for several weeks, thereby consolidating this technology as an alternative to generating liver-specific knockout animals. PMID:18828727

  5. Sustained Phenotypic Correction in a Mouse Model of Hypoalphalipoproteinemia with a Helper-Dependent Adenovirus Vector

    PubMed Central

    Oka, Kazuhiro; Belalcazar, L. Maria; Dieker, Carrie; Nour, Elie A.; Nuno-Gonzalez, Patricia; Paul, Antoni; Cormier, Shelley; Shin, Jae-Kyung; Finegold, Milton; Chan, Lawrence

    2006-01-01

    We examined the efficacy and host response to the adenovirus (Ad)-mediated delivery of human apolipoprotein A-I (APOA1) gene to the liver of APOA1−/− mice. Administration of a first generation vector (FGAd-AI) resulted in a transient appearance of APOA1 in plasma and induced an anti-APOA1 antibody titer while treatment with a helper-dependent vector (HDAd-AI) resulted in sustained APOA1 expression without inducing an antibody titer. With these results, we studied the effects of FGAd vectors on APOAI expression by HDAd-AI vector. Co-treatment with a FGAd vector inhibited HDAd-AI-mediated APOA1 expression independent of transgene cassettes, but only FGAd-AI induced a humoral response. Furthermore, APOA1 mRNA levels in mice co-treated with FGAd vectors were much lower than those expected from the vector copy number, suggesting that DNA of FGAd vectors interferes with the HDAd-AI vector's APOA1 promoter. A single treatment with an HDAd-AI vector produced a supraphysiological plasma APOA1 level that gradually declined to about half the normal human level over the course of 2 years, associated with a plasma cholesterol level that is persistently higher than that in controls. This investigation provides the proof of principle that liver-directed HDAd gene delivery is effective for the long-term phenotypic correction of monogenic hypoalphalipoproteinemia. PMID:16957769

  6. PEGylated helper-dependent adenoviral vectors: highly efficient vectors with an enhanced safety profile.

    PubMed

    Croyle, M A; Le, H T; Linse, K D; Cerullo, V; Toietta, G; Beaudet, A; Pastore, L

    2005-04-01

    Transgene expression from helper-dependent adenoviral (HD-Ad) vectors is effective and long lasting, but not permanent. Their use is also limited by the host response against capsid proteins that precludes successful gene expression upon readministration. In this report, we test the hypothesis that PEGylation of HD-Ad reduces its toxicity and promotes transgene expression upon readministration. PEGylation did not compromise transduction efficiency in vitro and in vivo and reduced peak serum IL-6 levels two-fold. IL-12 and TNF-alpha levels were reduced three- and seven-fold, respectively. Thrombocytopenia was not detected in mice treated with the PEGylated vector. Serum transaminases were not significantly elevated in mice treated with either vector. Mice immunized with 1 x 10(11) particles of unmodified HD-Ad expressing human alpha-1 antitrypsin (hA1AT) were rechallenged 28 days later with 8 x 10(10) particles of unmodified or PEG-conjugated vector expressing beta-galactosidase. Trace levels of beta-galactosidase (52.23+/-19.2 pg/mg protein) were detected in liver homogenates of mice that received two doses of unmodified HD-Ad. Mice rechallenged with PEGylated HD-Ad produced significant levels of beta-galactosidase (5.1+/-0.4 x 10(5) pg/mg protein, P=0.0001). This suggests that PEGylation of HD-Ad vectors may be appropriate for their safe and efficient use in the clinic. PMID:15647765

  7. Identification of FAM111A as an SV40 host range restriction and adenovirus helper factor.

    PubMed

    Fine, Debrah A; Rozenblatt-Rosen, Orit; Padi, Megha; Korkhin, Anna; James, Robert L; Adelmant, Guillaume; Yoon, Rosa; Guo, Luxuan; Berrios, Christian; Zhang, Ying; Calderwood, Michael A; Velmurgan, Soundarapandian; Cheng, Jingwei; Marto, Jarrod A; Hill, David E; Cusick, Michael E; Vidal, Marc; Florens, Laurence; Washburn, Michael P; Litovchick, Larisa; DeCaprio, James A

    2012-01-01

    The small genome of polyomaviruses encodes a limited number of proteins that are highly dependent on interactions with host cell proteins for efficient viral replication. The SV40 large T antigen (LT) contains several discrete functional domains including the LXCXE or RB-binding motif, the DNA binding and helicase domains that contribute to the viral life cycle. In addition, the LT C-terminal region contains the host range and adenovirus helper functions required for lytic infection in certain restrictive cell types. To understand how LT affects the host cell to facilitate viral replication, we expressed full-length or functional domains of LT in cells, identified interacting host proteins and carried out expression profiling. LT perturbed the expression of p53 target genes and subsets of cell-cycle dependent genes regulated by the DREAM and the B-Myb-MuvB complexes. Affinity purification of LT followed by mass spectrometry revealed a specific interaction between the LT C-terminal region and FAM111A, a previously uncharacterized protein. Depletion of FAM111A recapitulated the effects of heterologous expression of the LT C-terminal region, including increased viral gene expression and lytic infection of SV40 host range mutants and adenovirus replication in restrictive cells. FAM111A functions as a host range restriction factor that is specifically targeted by SV40 LT. PMID:23093934

  8. Haptoglobin directly affects T cells and suppresses T helper cell type 2 cytokine release

    PubMed Central

    Arredouani, M; Matthijs, P; Van Hoeyveld, E; Kasran, A; Baumann, H; Ceuppens, J L; Stevens, E

    2003-01-01

    T helper cell type 1 (Th1) and type 2 (Th2) immune responses are characterized by a different pattern of cytokine expression following T-cell activation. Alterations of the ratio of Th1 to Th2 cells are important determinants of susceptibility to viral and parasitic infections, allergies, anti-tumour responses, and autoimmunity. In this work we bring new evidence for an effect of haptoglobin (Hp), a positive acute-phase protein, on T-lymphocyte functions. We show that Hp specifically interacts with both resting and activated CD4+ and CD8+ T cells. This specific binding results in a strong suppression of induced T-cell proliferation. In addition, Hp exhibits a strong in vitro inhibitory effect on Th2 cytokine release, while the production of interferon-γ (IFN-γ) and interleukin-2 (IL-2) is only slightly inhibited at high Hp doses. As a result, the presence of Hp promotes Th1 activation over Th2 activation in vivo as evidenced in Hp-deficient mice. Anti-CD3 monoclonal antibody injection indeed resulted in predominant IL-4 production in Hp−/− mice, in contrast to predominant IFN-γ production in Hp+/+ mice. We conclude that Hp plays a modulating role on the Th1/Th2 balance by promoting a dominant Th1 cellular response. This points to a role of acute-phase proteins in balancing immune responses. PMID:12562322

  9. Theory and experimental validation of SPLASH (Single Panel Lamp and Shroud Helper).

    SciTech Connect

    Larsen, Marvin Elwood; Porter, Jason M.

    2005-06-01

    The radiant heat test facility develops test sets providing well-characterized thermal environments, often representing fires. Many of the components and procedures have become standardized to such an extent that the development of a specialized design tool was appropriate. SPLASH (Single Panel Lamp and Shroud Helper) is that tool. SPLASH is implemented as a user-friendly program that allows a designer to describe a test setup in terms of parameters such as lamp number, power, position, and separation distance. Thermal radiation is the dominant mechanism of heat transfer and the SPLASH model solves a radiation enclosure problem to estimate temperature distributions in a shroud providing the boundary condition of interest. Irradiance distribution on a specified viewing plane is also estimated. This document provides the theoretical development for the underlying model. A series of tests were conducted to characterize SPLASH's ability to analyze lamp and shroud systems. The comparison suggests that SPLASH succeeds as a design tool. Simplifications made to keep the model tractable are demonstrated to result in estimates that are only approximately as uncertain as many of the properties and characteristics of the operating environment.

  10. Advances in T Helper 17 Cell Biology: Pathogenic Role and Potential Therapy in Multiple Sclerosis

    PubMed Central

    Volpe, Elisabetta; Battistini, Luca; Borsellino, Giovanna

    2015-01-01

    The discovery of the T helper (Th) 17 lineage, involved in the protection against fungal and extracellular bacterial infections, has profoundly revolutionized our current understanding of T cell-mediated responses in autoimmune diseases, including multiple sclerosis (MS). Indeed, recent data demonstrate the pathogenic role of Th17 cells in autoimmune disorders. In particular, studies in MS and in its animal model (EAE, experimental autoimmune encephalomyelitis) have revealed a crucial role of Th17 cells in the pathogenesis of autoimmune demyelinating diseases in both mice and humans. Over the past years, several important aspects concerning Th17 cells have been elucidated, such as the factors which promote or inhibit their differentiation and the effector cytokines which mediate their responses. The identification of the features endowing Th17 cells with high pathogenicity in MS is of particular interest, and discoveries in Th17 cell biology and function could lead to the design of new strategies aimed at modulating the immune response in MS. Here, we will discuss recent advances in this field, with particular focus on the mechanisms conferring pathogenicity in MS and their potential modulation. PMID:26770017

  11. Bob1 limits cellular frequency of T-follicular helper cells.

    PubMed

    Yamashita, Keiji; Kawata, Koji; Matsumiya, Hiroshi; Kamekura, Ryuta; Jitsukawa, Sumito; Nagaya, Tomonori; Ogasawara, Noriko; Takano, Ken-Ichi; Kubo, Terufumi; Kimura, Sachiko; Shigehara, Katsunori; Himi, Tetsuo; Ichimiya, Shingo

    2016-06-01

    T follicular helper (Tfh) cells are involved in specific humoral immunity at initial and recall phases. The fact that the transcription repressors B-cell lymphoma-6 and Blimp-1 determine lineages of Tfh cells and other types of effector CD4(+) T cells, respectively, suggests that there are unique mechanisms to establish Tfh-cell identity. In this study, we found that Tfh cells preferentially express the transcriptional coactivator Bob1. Bob1 of Tfh cells was dispensable for the expression of B-cell lymphoma-6 and the functional property of the cells for B cell help. However, upon initial immunization of foreign antigens, the percentages of Tfh cells in Bob1(-/-) mice were much higher than those in wild-type (WT) mice. In addition, expansion of Tfh cells within Bob1(-/-) CD4(+) T cells transferred into WT mice revealed that the high frequency of Tfh cells was caused by a T-cell-intrinsic mechanism. These findings were further supported by the results of in vitro studies demonstrating that Bob1(-/-) Tfh cells had greater proliferative activity in response to stimuli by CD3/CD28 monoclonal antibody and were also refractory to CD3-induced cell death in comparison to WT Tfh cells. These results suggest that Tfh cells harbor a Bob1-related mechanism to restrict numerical frequency against stimulation of TCRs.

  12. Dynamic BRG1 Recruitment during T Helper Differentiation and Activation Reveals Distal Regulatory Elements▿§

    PubMed Central

    De, Supriyo; Wurster, Andrea L.; Precht, Patricia; Wood, William H.; Becker, Kevin G.; Pazin, Michael J.

    2011-01-01

    T helper cell differentiation and activation require specific transcriptional programs accompanied by changes in chromatin structure. However, little is known about the chromatin remodeling enzymes responsible. We performed genome-wide analysis to determine the general principles of BRG1 binding, followed by analysis of specific genes to determine whether these general rules were typical of key T cell genes. We found that binding of the remodeling protein BRG1 was programmed by both lineage and activation signals. BRG1 binding positively correlated with gene activity at protein-coding and microRNA (miRNA) genes. BRG1 binding was found at promoters and distal regions, including both novel and previously validated distal regulatory elements. Distal BRG1 binding correlated with expression, and novel distal sites in the Gata3 locus possessed enhancer-like activity, suggesting a general role for BRG1 in long-distance gene regulation. BRG1 recruitment to distal sites in Gata3 was impaired in cells lacking STAT6, a transcription factor that regulates lineage-specific genes. Together, these findings suggest that BRG1 interprets both differentiation and activation signals and plays a causal role in gene regulation, chromatin structure, and cell fate. Our findings suggest that BRG1 binding is a useful marker for identifying active cis-regulatory regions in protein-coding and miRNA genes. PMID:21262765

  13. Dynamic BRG1 recruitment during T helper differentiation and activation reveals distal regulatory elements.

    PubMed

    De, Supriyo; Wurster, Andrea L; Precht, Patricia; Wood, William H; Becker, Kevin G; Pazin, Michael J

    2011-04-01

    T helper cell differentiation and activation require specific transcriptional programs accompanied by changes in chromatin structure. However, little is known about the chromatin remodeling enzymes responsible. We performed genome-wide analysis to determine the general principles of BRG1 binding, followed by analysis of specific genes to determine whether these general rules were typical of key T cell genes. We found that binding of the remodeling protein BRG1 was programmed by both lineage and activation signals. BRG1 binding positively correlated with gene activity at protein-coding and microRNA (miRNA) genes. BRG1 binding was found at promoters and distal regions, including both novel and previously validated distal regulatory elements. Distal BRG1 binding correlated with expression, and novel distal sites in the Gata3 locus possessed enhancer-like activity, suggesting a general role for BRG1 in long-distance gene regulation. BRG1 recruitment to distal sites in Gata3 was impaired in cells lacking STAT6, a transcription factor that regulates lineage-specific genes. Together, these findings suggest that BRG1 interprets both differentiation and activation signals and plays a causal role in gene regulation, chromatin structure, and cell fate. Our findings suggest that BRG1 binding is a useful marker for identifying active cis-regulatory regions in protein-coding and miRNA genes.

  14. C-reactive protein directly suppresses T helper 1 cell differentiation and alleviates experimental autoimmune encephalomyelitis

    PubMed Central

    Zhang, Lin; Liu, Shan-Hui; Wright, Tyler T.; Shen, Zhi-Yuan; Li, Hai-Yun; Zhu, Wei; Potempa, Lawrence A.; Ji, Shang-Rong; Szalai, Alexander J.; Wu, Yi

    2015-01-01

    Human C-reactive protein (CRP) is a serum soluble pattern recognition receptor (PRR) that serves as a marker of inflammation and directly contributes to innate immunity. Herein we show that human CRP also directly contributes to adaptive immunity, i.e. native CRP binds specifically to human Jurkat T cells and to mouse naïve CD4+ T cells and modulates their T helper (Th) 1 and Th2 responses. In vitro both exogenously added (purified) and endogenously expressed (via transfection) human CRP inhibited Th1 differentiation and augmented Th2 differentiation of naïve CD4+ T cells. In vivo for human CRP transgenic (CRPtg) compared to wild type mice, a lesser proportion of the T cells recovered from the spleens of healthy animals were Th1 cells. Moreover in both CRPtg mice and in wild type mice treated with human CRP, during myelin oligodendrocyte glycoprotein peptide induced experimental autoimmune encephalomyelitis both the Th1 cell response and disease severity were inhibited. These pattern recognition-independent actions of CRP directly on T cells highlights the potential for this soluble PRR to act as a tonic regulator of immunity, shaping global adaptive immune responses during both homeostasis and disease. PMID:25917100

  15. Instruction for Cytokine Expression in T Helper Lymphocytes in Relation to Proliferation and Cell Cycle Progression

    PubMed Central

    Richter, Anne; Löhning, Max; Radbruch, Andreas

    1999-01-01

    T helper (Th) lymphocytes, when reactivated, recall expression of those cytokines they had been instructed to express in earlier activations, even in the absence of specific cytokine-inducing factors. In cells that memorize their expression, the cytokine genes are modified by chromatin rearrangement and demethylation, suggesting that they have been somatically imprinted. Here we show, by using inhibitors blocking the cell cycle in various stages, that for the instruction of a Th cell to express interleukin (IL)-4 or IL-10 upon restimulation, entry of the cell into the S phase of the first cell cycle after initial activation is required. Separation of the IL-4 receptor (IL-4R) and T cell antigen receptor (TCR) signals in time, demonstrates that this instruction is dependent on concomitant signaling from both receptors. In Th cells, inhibited to progress into the first S phase after activation, the IL-4R and TCR signals can be memorized for at least 1 d, priming the T cell to become instructed for expression of IL-4 upon restimulation, when entering the S phase after release of the cell cycle block. The requirement of the initial S phase of T cell activation, for instruction of Th cells to express IL-4 or IL-10 upon restimulation points to the decisive role of epigenetic modification of cytokine genes as a molecular correlate of the memory to express particular cytokines. PMID:10562319

  16. Differentiation and recruitment of IL-22-producing helper T cells in lgA nephropathy

    PubMed Central

    Xiao, Chenggen; Zhou, Qiaoling; Li, Xiaozhao; Li, Hui; Meng, Ting; Zhong, Yong; Pu, Jiaxi; Zhu, Mengyuan; Xu, Yan; Gan, Lu; Sun, Hong; Xiao, Ping

    2016-01-01

    IL-22-producing helper T cells (Th22 cells) have been reported to be involved in lgA nephropathy. However, the mechanisms underlying the differentiation and immune regulation of Th22 cells in lgA nephropathy remain unknown. To elucidate the mechanisms by which Th22 cells differentiate and are recruited into the kidney in lgA nephropathy, the distribution of Th22 cells in both the kidney and blood was determined. Additionally, the impacts of proinflammatory cytokines and antigen presentation in the kidney on Th22 cell differentiation were explored. Specifically, the chemoattractant activities of chemokines produced by the kidney for Th22 cells were investigated. Th22 cells were significantly higher both in the kidney and in the blood in lgA nephropathy mice. IL-1β, IL-6, IL-21 and/or TNF-a promoted Th22 cells differentiation from CD4+ T cells. It was observed that kidneys undergoing lgA nephropathy expressed CCL20, CCL22 and CCL27, and kidney supernatants were chemotactic for Th22 cells. This activity was partially blocked by anti-CCL20, anti-CCL22, and anti-CCL27 antibodies, which also potentially improved renal lesions simultaneously. The overrepresentation of Th22 cells in lgAN may be attributable to the actions of kidney chemokines and cytokines. Our data suggest a collaborative loop between the kidney and Th22 cells in lgA nephropathy. PMID:27725866

  17. Influence of helper T cells on the expression of a murine intrastrain crossreactive idiotype.

    PubMed Central

    Hathcock, K S; Gurish, M F; Nisonoff, A; Conger, J D; Hodes, R J

    1986-01-01

    The requirement for idiotype-specific helper T (Th) cells in the generation of a major intrastrain crossreactive idiotype was investigated. This idiotype, designated CRIA, is associated with a large proportion of anti-p-azobenzenearsonate (anti-Ar) antibodies in A/J mice. Secondary in vitro responses were studied. Using carrier-primed heterogeneous Th-cell populations, it was found that CRIA expression is determined by the mouse strain that provides the responding B cells and is independent of the strain of the Th cells functioning in vitro. Thus, A/J or A.BY (Ighe) B-plus-accessory-cell populations, primed in vivo to keyhole limpet hemocyanin-Ar (KLH-Ar), generated CRIA-dominant responses in vitro in the presence of KLH-Ar regardless of whether the KLH-primed Th cells were derived from CRIA+ strains (A/J or A.BY, Ighe) or CRIA- strains (B10.A or C57BL/10, Ighb). Further, when major histocompatibility complex-restricted, KLH-specific Th-cell clones were used, the CRIA dominance of the Ar-specific responses was again determined by the strain providing B plus accessory cells. Similar levels of expression of CRIA in Ar-specific antibodies were generated in the presence of heterogeneous or cloned Th cells. The results suggest that there is no absolute requirement for idiotype-specific Th cells in generating an Ar-specific secondary antibody response in vitro. PMID:2934739

  18. Activated Circulating T Follicular Helper Cells Are Associated with Disease Severity in Patients with Psoriasis

    PubMed Central

    Wang, Ying; Yang, Haoyu; Yuan, Weichang; Ren, Jingyi

    2016-01-01

    Circulating T follicular helper (cTfh) cells are known to be involved in numerous immune-mediated diseases, but their pathological role in psoriasis is less fully investigated. Herein, we aimed to identify whether cTfh cells contributed to the pathogenesis of psoriasis. The frequency and function of cTfh cells were compared between patients with psoriasis vulgaris and healthy controls, and the infiltration of Tfh cells was detected between lesional and nonlesional skin tissues of psoriasis patients. Moreover, the dynamic change of cTfh cells before and after acitretin treatment was evaluated. Our results showed both increased frequency and activation (indicated by higher expression of ICOS, PD-1, HLA-DR, and Ki-67 and increased production of IL-21, IL-17, and IFN-γ) of cTfh cells in psoriasis patients. Compared with nonlesional skin tissues of psoriasis patients, the number of infiltrated Tfh cells was significantly increased in psoriasis lesions. In addition, positive correlations between the percentage of cTfh, functional markers on cTfh cells in peripheral blood and disease severity were noted. Furthermore, the frequency of cTfh cells and the levels of cytokines secreted by cTfh cells were all significantly decreased after 1-month treatment. PMID:27774460

  19. The T helper type 17/regulatory T cell paradigm in pregnancy.

    PubMed

    Figueiredo, Ana Sofia; Schumacher, Anne

    2016-05-01

    T helper type 17 (Th17) and regulatory T (Treg) cells are active players in the establishment of tolerance and defence. These attributes of the immune system enmesh to guarantee the right level of protection. The healthy immune system, on the one hand, recognizes and eliminates dangerous non-self pathogens and, on the other hand, protects the healthy self. However, there are circumstances where this fine balance is disrupted. In fact, in situations such as in pregnancy, the foreign fetal antigens challenge the maternal immune system and Treg cells will dominate Th17 cells to guarantee fetal survival. In other situations such as autoimmunity, where the Th17 responses are often overwhelming, the immune system shifts towards an inflammatory profile and attacks the healthy tissue from the self. Interestingly, autoimmune patients have meliorating symptoms during pregnancy. This connects with the antagonist role of Th17 and Treg cells, and their specific profiles during these two immune challenging situations. In this review, we put into perspective the Th17/Treg ratio during pregnancy and autoimmunity, as well as in pregnant women with autoimmune conditions. We further review existing systems biology approaches that study specific mechanisms of these immune cells using mathematical modelling and we point out possible future directions of investigation. Understanding what maintains or disrupts the balance between these two opponent yet reciprocal cells in healthy physiological settings, sheds light into the development of innovative pharmacological approaches to fight pregnancy loss and autoimmunity. PMID:26855005

  20. Proatherogenic conditions promote autoimmune T helper 17 cell responses in vivo.

    PubMed

    Lim, Hoyong; Kim, Young Uk; Sun, Hua; Lee, Joyce H; Reynolds, Joseph M; Hanabuchi, Shino; Wu, Huaizhu; Teng, Ba-Bie; Chung, Yeonseok

    2014-01-16

    Patients with systemic autoimmune diseases show increased incidence of atherosclerosis. However, the contribution of proatherogenic factors to autoimmunity remains unclear. We found that atherogenic mice (herein referred to as LDb mice) exhibited increased serum interleukin-17, which was associated with increased numbers of T helper 17 (Th17) cells in secondary lymphoid organs. The environment within LDb mice was substantially favorable for Th17 cell polarization of autoreactive T cells during homeostatic proliferation, which was considerably inhibited by antibodies directed against oxidized low-density lipoprotein (oxLDL). Moreover, the uptake of oxLDL induced dendritic-cell-mediated Th17 cell polarization by triggering IL-6 production in a process dependent on TLR4, CD36, and MyD88. Furthermore, self-reactive CD4(+) T cells that expanded in the presence of oxLDL induced more profound experimental autoimmune encephalomyelitis. These findings demonstrate that proatherogenic factors promote the polarization and inflammatory function of autoimmune Th17 cells, which could be critical for the pathogenesis of atherosclerosis and other related autoimmune diseases.

  1. CD301b+ dendritic cells suppress T follicular helper cells and antibody responses to protein antigens

    PubMed Central

    Kumamoto, Yosuke; Hirai, Toshiro; Wong, Patrick W; Kaplan, Daniel H; Iwasaki, Akiko

    2016-01-01

    Strong antibody response is considered a hallmark of a successful vaccine. While dendritic cells (DCs) are important for T follicular helper (Tfh) cell priming, how this process is regulated in vivo is unclear. We show here that the depletion of CD301b+ DCs specifically enhanced the development of Tfh cells, germinal center B cells and antibody responses against protein antigens. Exaggerated antibody responses in mice depleted of CD301b+ DCs occurred in the absence of any adjuvants, and resulting antibodies had broader specificity and higher affinity to the immunogen. CD301b+ DCs express high levels of PD-1 ligands, PD-L1 and PD-L2. Blocking PD-1 or PD-L1 during priming in wild-type mice partially mimicked the phenotype of CD301b+ DC-depleted animals, suggesting their role in Tfh suppression. Transient depletion of CD301b+ DC results in the generation of autoreactive IgG responses. These results revealed a novel regulatory mechanism and a key role of CD301b+ DCs in blocking autoantibody generation. DOI: http://dx.doi.org/10.7554/eLife.17979.001 PMID:27657168

  2. Accumulation of helper component/proteinase and coat protein of turnip mosaic virus in intact plants.

    PubMed

    Ohshima, K

    1999-02-01

    The helper component/proteinase (HC/Pro) protein of turnip mosaic virus (TuMV) was fused with glutathione S-transferase (GST) and expressed as a fusion protein in Escherichia coli. The quality of antiserum raised against the GST-HC/Pro fusion protein was compared to that of antiserum raised against coat protein (CP) by image analyser. The result showed that these antisera were of similar quality. Then the both antisera were used to follow the time course of accumulation of HC/Pro protein and CP in intact TuMV-infected leaves. CP appeared first at day 3 post inoculation (p.i.) and gradually accumulated in uninoculated upper leaves, whereas HC/Pro protein appeared first at day 4 p.i., accumulated up to day 7 p.i. and then gradually decreased. Potyvirus proteins are encoded by a single translation unit spanning most of the genome and are presumably synthesized in equimolar ratios. Therefore, the reduced accumulation of HC/Pro protein in relation to CP at one month p.i. in infected plants is presumed to be the result of its degradation. PMID:10672341

  3. Interleukin-9 and T helper type 9 cells in rheumatic diseases.

    PubMed

    Ciccia, F; Guggino, G; Ferrante, A; Cipriani, P; Giacomelli, R; Triolo, G

    2016-08-01

    Interleukin (IL)-9 is a 28-30 kDa monomeric glycosylated polypeptide belonging to the IL-7/IL-9 family of proteins that bind to a composite receptor consisting of the private receptor IL-9R and the IL-2 receptor, gamma (IL-2RG), a common gamma subunit shared by the receptors of many different cytokines. The IL-9R is expressed widely and IL-9 impacts a number of effector cells, such as effector T cells, B cells, innate lymphoid cells, mast cells, polymorphonuclear cells, epithelial cells and smooth muscle cells, playing an important role in regulating inflammatory immunity. The critical role of IL-9 in promoting cellular and humoral immune responses makes it an important focus of potential therapeutic interventions. Recently, a defined subset of T helper type cells, Th9 cells, has been identified by the potent production of IL-9. The involvement of the Th9 cell subset has been described in many types of inflammatory diseases, namely atopic diseases, helminth infections, experimental autoimmune encephalomyelitis and ulcerative colitis. In this review, we summarize the IL-9 biological activities, highlighting roles for IL-9 and Th9 cells in rheumatoid and psoriatic arthritis, systemic vasculitis, systemic lupus erythematosus and systemic sclerosis. PMID:27159882

  4. T regulatory (Treg) and T helper 17 (Th17) lymphocytes in thyroid autoimmunity.

    PubMed

    González-Amaro, Roberto; Marazuela, Mónica

    2016-04-01

    Different immune cell subsets have a relevant role in the pathogenesis of and tissue damage seen in autoimmune thyroid diseases (AITD), including T regulatory (Treg) lymphocytes and T helper (Th) 17 cells. There are several types of CD4+ Treg cells (Foxp3+, CD69+, Tr1), which are able to prevent the appearance of autoimmune diseases, down regulating the immune response and the inflammatory phenomenon. However, despite their presence in peripheral blood and thyroid tissue from patients with AITD, these cells are apparently unable to put down the autoimmune process. Moreover, many reports indicate the involvement of Th17 cells in chronic inflammatory diseases, including AITD. Nevertheless, it is now evident that these lymphocytes show a remarkable plasticity, giving rise to anti-inflammatory (including Treg lymphocytes) and pro-inflammatory cell subtypes. Nowadays, both Treg and Th17 cells must be considered as key elements in the pathogenesis of AITD as well as plausible potential targets for the next generation of therapeutic options of this condition.

  5. Social genetic and social environment effects on parental and helper care in a cooperatively breeding bird

    PubMed Central

    Adams, Mark James; Robinson, Matthew R.; Mannarelli, Maria-Elena; Hatchwell, Ben J.

    2015-01-01

    Phenotypes expressed in a social context are not only a function of the individual, but can also be shaped by the phenotypes of social partners. These social effects may play a major role in the evolution of cooperative breeding if social partners differ in the quality of care they provide and if individual carers adjust their effort in relation to that of other carers. When applying social effects models to wild study systems, it is also important to explore sources of individual plasticity that could masquerade as social effects. We studied offspring provisioning rates of parents and helpers in a wild population of long-tailed tits Aegithalos caudatus using a quantitative genetic framework to identify these social effects and partition them into genetic, permanent environment and current environment components. Controlling for other effects, individuals were consistent in their provisioning effort at a given nest, but adjusted their effort based on who was in their social group, indicating the presence of social effects. However, these social effects differed between years and social contexts, indicating a current environment effect, rather than indicating a genetic or permanent environment effect. While this study reveals the importance of examining environmental and genetic sources of social effects, the framework we present is entirely general, enabling a greater understanding of potentially important social effects within any ecological population. PMID:26063846

  6. Characterizing clearance of helper adenovirus by a clinical rAAV1 manufacturing process.

    PubMed

    Thorne, Barbara A; Quigley, Paulene; Nichols, Gina; Moore, Christine; Pastor, Eric; Price, David; Ament, Jon W; Takeya, Ryan K; Peluso, Richard W

    2008-01-01

    Recombinant adeno-associated viral vectors (rAAV) are being developed as gene therapy delivery vehicles and as genetic vaccines, and some of the most scaleable manufacturing methods for rAAV use live adenovirus to induce production. One aspect of establishing safety of rAAV products is therefore demonstrating adequate and reliable clearance of this helper virus by the vector purification process. The ICH Q5A regulatory guidance on viral safety provides recommendations for process design and characterization of viral clearance for recombinant proteins, and these principles were adapted to a rAAV serotype 1 purification process for clinical vectors. Specific objectives were to achieve overall adenovirus clearance factors significantly greater than input levels by using orthogonal separation and inactivation methods, and to segregate adenovirus from downstream operations by positioning a robust clearance step early in the process. Analytical tools for process development and characterization addressed problematic in-process samples, and a viral clearance validation study was performed using adenovirus and two non-specific model viruses. Overall clearance factors determined were >23 LRV for adenovirus, 11 LRV for BVDV, and >23 LRV for AMuLV.

  7. T Follicular Helper Cells and Regulatory B Cells Dynamics in Systemic Lupus Erythematosus

    PubMed Central

    Chu, Yiwei; Xue, Yu; Xuan, Dandan; Zheng, Shucong; Zou, Hejian

    2014-01-01

    T follicular helper (Tfh) cells aid effector B cells, and augment autoimmunity, whereas the role of Tfh cells on regulatory B (Breg) cells in systemic lupus erythematosus (SLE) is not known. The aim of this study is to investigate the percentage of Breg cells in SLE, and the role of Tfh cells on Breg cells. First, we demonstrated the presence of Breg cells in SLE peripheral blood mononuclear cells and in involved skins. Both the percentage of circulating Breg cells and the ability to produce interleukin-10 (IL-10) were elevated in SLE patients. The percentage of Breg cells increased during SLE flares and decreased following disease remission. Second, Tfh cell expansion was not only related to autoantibody production but also correlated with the increased percentage of Breg cells. Third, in vitro studies revealed that Tfh cell-derived IL-21 could promote IL-10 production and Breg cell differentiation. In conclusions, these data imply that SLE flares may be linked to the expansion of Tfh cells and that Breg cells are increased in a regulatory feedback manner. Thus, SLE development may be associated with the complex regulation of Tfh cells and diverse B cell subsets. PMID:24551101

  8. Evaluation of helper-dependent canine adenovirus vectors in a 3D human CNS model.

    PubMed

    Simão, D; Pinto, C; Fernandes, P; Peddie, C J; Piersanti, S; Collinson, L M; Salinas, S; Saggio, I; Schiavo, G; Kremer, E J; Brito, C; Alves, P M

    2016-01-01

    Gene therapy is a promising approach with enormous potential for treatment of neurodegenerative disorders. Viral vectors derived from canine adenovirus type 2 (CAV-2) present attractive features for gene delivery strategies in the human brain, by preferentially transducing neurons, are capable of efficient axonal transport to afferent brain structures, have a 30-kb cloning capacity and have low innate and induced immunogenicity in preclinical tests. For clinical translation, in-depth preclinical evaluation of efficacy and safety in a human setting is primordial. Stem cell-derived human neural cells have a great potential as complementary tools by bridging the gap between animal models, which often diverge considerably from human phenotype, and clinical trials. Herein, we explore helper-dependent CAV-2 (hd-CAV-2) efficacy and safety for gene delivery in a human stem cell-derived 3D neural in vitro model. Assessment of hd-CAV-2 vector efficacy was performed at different multiplicities of infection, by evaluating transgene expression and impact on cell viability, ultrastructural cellular organization and neuronal gene expression. Under optimized conditions, hd-CAV-2 transduction led to stable long-term transgene expression with minimal toxicity. hd-CAV-2 preferentially transduced neurons, whereas human adenovirus type 5 (HAdV5) showed increased tropism toward glial cells. This work demonstrates, in a physiologically relevant 3D model, that hd-CAV-2 vectors are efficient tools for gene delivery to human neurons, with stable long-term transgene expression and minimal cytotoxicity.

  9. Basic science for the clinician 28: T-helper cell subtypes.

    PubMed

    Sigal, Leonard H

    2004-08-01

    The immune response is finely tuned to the various invaders that may cause damage and disease. There is an innate immune system and an acquired immune response, but there is much overlap and recruitment across these lines of demarcation. Broadly speaking, there are cellular immune responses (cellular effectors that identify intracellular pathogens and damage and kill the affected cell) and humoral (B cells become plasma cells which make antibodies to bind extracellular pathogens and their products) that draw upon both systems. At the pivotal point, where decisions are made whether to mount a primarily cellular or a humoral response are T-helper cells (CD4). As you may have read, CD4 cells come in at least 2 subtypes: TH1 cells predispose to the development of a primarily cellular responses and TH2 predispose to humoral responses. Not very complicated, but worthy of some discussion to look at the cytokines produced, the changes these cytokines evince, and how the balances (dare I say yin and yang) keep us healthy but also may get us into trouble!

  10. Social genetic and social environment effects on parental and helper care in a cooperatively breeding bird.

    PubMed

    Adams, Mark James; Robinson, Matthew R; Mannarelli, Maria-Elena; Hatchwell, Ben J

    2015-07-01

    Phenotypes expressed in a social context are not only a function of the individual, but can also be shaped by the phenotypes of social partners. These social effects may play a major role in the evolution of cooperative breeding if social partners differ in the quality of care they provide and if individual carers adjust their effort in relation to that of other carers. When applying social effects models to wild study systems, it is also important to explore sources of individual plasticity that could masquerade as social effects. We studied offspring provisioning rates of parents and helpers in a wild population of long-tailed tits Aegithalos caudatus using a quantitative genetic framework to identify these social effects and partition them into genetic, permanent environment and current environment components. Controlling for other effects, individuals were consistent in their provisioning effort at a given nest, but adjusted their effort based on who was in their social group, indicating the presence of social effects. However, these social effects differed between years and social contexts, indicating a current environment effect, rather than indicating a genetic or permanent environment effect. While this study reveals the importance of examining environmental and genetic sources of social effects, the framework we present is entirely general, enabling a greater understanding of potentially important social effects within any ecological population.

  11. CD4+ follicular helper T cell infiltration predicts breast cancer survival

    PubMed Central

    Gu-Trantien, Chunyan; Loi, Sherene; Garaud, Soizic; Equeter, Carole; Libin, Myriam; de Wind, Alexandre; Ravoet, Marie; Le Buanec, Hélène; Sibille, Catherine; Manfouo-Foutsop, Germain; Veys, Isabelle; Haibe-Kains, Benjamin; Singhal, Sandeep K.; Michiels, Stefan; Rothé, Françoise; Salgado, Roberto; Duvillier, Hugues; Ignatiadis, Michail; Desmedt, Christine; Bron, Dominique; Larsimont, Denis; Piccart, Martine; Sotiriou, Christos; Willard-Gallo, Karen

    2013-01-01

    CD4+ T cells are critical regulators of immune responses, but their functional role in human breast cancer is relatively unknown. The goal of this study was to produce an image of CD4+ T cells infiltrating breast tumors using limited ex vivo manipulation to better understand the in vivo differences associated with patient prognosis. We performed comprehensive molecular profiling of infiltrating CD4+ T cells isolated from untreated invasive primary tumors and found that the infiltrating T cell subpopulations included follicular helper T (Tfh) cells, which have not previously been found in solid tumors, as well as Th1, Th2, and Th17 effector memory cells and Tregs. T cell signaling pathway alterations included a mixture of activation and suppression characterized by restricted cytokine/chemokine production, which inversely paralleled lymphoid infiltration levels and could be reproduced in activated donor CD4+ T cells treated with primary tumor supernatant. A comparison of extensively versus minimally infiltrated tumors showed that CXCL13-producing CD4+ Tfh cells distinguish extensive immune infiltrates, principally located in tertiary lymphoid structure germinal centers. An 8-gene Tfh signature, signifying organized antitumor immunity, robustly predicted survival or preoperative response to chemotherapy. Our identification of CD4+ Tfh cells in breast cancer suggests that they are an important immune element whose presence in the tumor is a prognostic factor. PMID:23778140

  12. Thimerosal compromises human dendritic cell maturation, IL-12 production, chemokine release, and T-helper polarization

    PubMed Central

    Loison, Emily; Gougeon, Marie-Lise

    2014-01-01

    Thimerosal is a preservative used in multidose vials of vaccine formulations to prevent bacterial and fungal contamination. We recently reported that nanomolar concentrations of thimerosal induce cell cycle arrest of human T cells activated via the TCR and inhibition of proinflammatory cytokine production, thus interfering with T-cell functions. Given the essential role of dendritic cells (DCs) in T-cell polarization and vaccine immunity, we studied the influence of non-toxic concentrations of thimerosal on DC maturation and functions. Ex-vivo exposure of human monocyte-derived DCs to nanomolar concentrations of thimerosal prevented LPS-induced DC maturation, as evidenced by the inhibition of morphological changes and a decreased expression of the maturation markers CD86 and HLA-DR. In addition thimerosal dampened their proinflammatory response, in particular the production of the Th1 polarizing cytokine IL-12, as well as TNF-α and IL-6. DC-dependent T helper polarization was altered, leading to a decreased production of IFN-γ IP10 and GM-CSF and increased levels of IL-8, IL-9, and MIP-1α. Although multi-dose vials of vaccines containing thimerosal remain important for vaccine delivery, our results alert about the ex-vivo immunomodulatory effects of thimerosal on DCs, a key player for the induction of an adaptive response PMID:25424939

  13. miR-155 promotes T follicular helper cell accumulation during chronic, low-grade inflammation.

    PubMed

    Hu, Ruozhen; Kagele, Dominique A; Huffaker, Thomas B; Runtsch, Marah C; Alexander, Margaret; Liu, Jin; Bake, Erin; Su, Wei; Williams, Matthew A; Rao, Dinesh S; Möller, Thomas; Garden, Gwenn A; Round, June L; O'Connell, Ryan M

    2014-10-16

    Chronic inflammation is a contributing factor to most life-shortening human diseases. However, the molecular and cellular mechanisms that sustain chronic inflammatory responses remain poorly understood, making it difficult to treat this deleterious condition. Using a mouse model of age-dependent inflammation that results from a deficiency in miR-146a, we demonstrate that miR-155 contributed to the progressive inflammatory disease that emerged as Mir146a(-/-) mice grew older. Upon analyzing lymphocytes from inflamed versus healthy middle-aged mice, we found elevated numbers of T follicular helper (Tfh) cells, germinal center (GC) B cells, and autoantibodies, all occurring in a miR-155-dependent manner. Further, Cd4-cre Mir155(fl/fl) mice were generated and demonstrated that miR-155 functions in T cells, in addition to its established role in B cells, to promote humoral immunity in a variety of contexts. Taken together, our study discovers that miR-146a and miR-155 counterregulate Tfh cell development that drives aberrant GC reactions during chronic inflammation. PMID:25367574

  14. An Instructive Component in T Helper Cell Type 2 (Th2) Development Mediated by Gata-3

    PubMed Central

    Farrar, J. David; Ouyang, Wenjun; Löhning, Max; Assenmacher, Mario; Radbruch, Andreas; Kanagawa, Osami; Murphy, Kenneth M.

    2001-01-01

    Although interleukin (IL)-12 and IL-4 polarize naive CD4+ T cells toward T helper cell type 1 (Th1) or Th2 phenotypes, it is not known whether cytokines instruct the developmental fate in uncommitted progenitors or select for outgrowth of cells that have stochastically committed to a particular fate. To distinguish these instructive and selective models, we used surface affinity matrix technology to isolate committed progenitors based on cytokine secretion phenotype and developed retroviral-based tagging approaches to directly monitor individual progenitor fate decisions at the clonal and population levels. We observe IL-4–dependent redirection of phenotype in cells that have already committed to a non–IL-4–producing fate, inconsistent with predictions of the selective model. Further, retroviral tagging of naive progenitors with the Th2-specific transcription factor GATA-3 provided direct evidence for instructive differentiation, and no evidence for the selective outgrowth of cells committed to either the Th1 or Th2 fate. These data would seem to exclude selection as an exclusive mechanism in Th1/Th2 differentiation, and support an instructive model of cytokine-driven transcriptional programming of cell fate decisions. PMID:11238595

  15. Two-photon microscopy for imaging germinal centers and T follicular helper cells.

    PubMed

    Clatworthy, Menna R

    2015-01-01

    One of the principle features of immune cells is their dynamic nature. Lymphocytes circulate in the blood between secondary lymphoid organs and tissues in an effort to maximize the likelihood of a rapid and appropriate immune response to invading pathogens and tissue damage. Conventional experimental techniques such as histology and flow cytometry have greatly increased our understanding of immune cells, but in the last decade, two-photon microscopy has revolutionized our ability to interrogate the dynamic behavior of immune cells, a facet so critical to their function. Two-photon microscopy relies on the excitation of fluorophores by simultaneous application of two photons of longer wavelength light. This allows a greater depth of imaging with minimal photodamage. Thus, living tissues can be imaged, including immune cells in lymph nodes. This technique has been used to interrogate the events occurring in a germinal center response and the interactions between cells in the germinal center, including T follicular helper cells (Tfh), germinal center B cells, and follicular dendritic cells (FDC). Herein, a method is described by which the interactions between Tfh and B cells within a germinal center in a popliteal lymph node can be imaged in a live mouse. PMID:25836302

  16. Counselor training as a treatment for alcoholism: the helper therapy principle in action.

    PubMed

    Kahn, M W; Fua, C

    1992-01-01

    Extensive harmful drinking of alcohol is a major problem for many groups of Australian Aborigines and western treatment approaches have had limited effect. In order to stress cultural factors in treatment, a program to train indigenous Aborigines as alcoholism counselors for their communities was developed. In its more than 10 years of existence 145 counselors have been graduated. Of those initially entering the two year program 60% have graduated. Most of those have found employment as alcohol counselors for their people, and the numbers of Aborigines treated has increased. About 90% of those who entered the training had severe repeated substance abuse disorders in their recent history. The training and the alcohol counseling employment appears to be highly associated with continuing sobriety. For those who graduated the program only 4.8% returned to drinking. Those who completed only the first phase, 8.4% returned to drinking. Of those who were terminated from the program, 74% returned to drinking. Training alcoholics as alcohol counselors appears to be associated with vocational success and maintenance of sobriety as predicted by Riessman's "helper-therapy principle." PMID:1428664

  17. Social networks and social support: implications for natural helper and community level interventions.

    PubMed

    Israel, B A

    1985-01-01

    The convincing evidence of the relationship between social support, social networks, and health status has influenced the development of program strategies which are relevant to health education. This article focuses on the linkage between social support and social networks and health education programs which involve interventions at the network and community level. Two broad strategies are addressed: programs enhancing entire networks through natural helpers; and programs strengthening overlapping networks/communities through key opinion and informal leaders who are engaged in the process of community wide problem-solving. Following a brief overview of definitions, this article highlights several network characteristics which are often found to be related to physical and mental health status. Suggestions are made for how these network characteristics can be applied to the two program strategies. Principles of practice for the health educator, and some of the limitations of a social network approach are delineated. The article concludes with a recommendation for engaging in action research--a perspective highly consistent with both the strategies discussed and the concepts of social networks and social support. This approach not only recognizes, but also acts to strengthen indigenous skills and resources. PMID:3980242

  18. Gender-specific differences in PPARγ regulation of follicular helper T cell responses with estrogen

    PubMed Central

    Park, Hong-Jai; Park, Hyeon-Soo; Lee, Jae-Ung; Bothwell, Alfred L. M.; Choi, Je-Min

    2016-01-01

    Peroxisome proliferator-activated receptor gamma (PPARγ), a master regulator of adipocyte differentiation, has recently been connected with effector T cells, though its role is still not clear. Here, we investigated the roles of PPARγ in follicular helper T (TFH) cell responses regarding gender specificity. NP-OVA immunization in female but not male CD4-PPARγKO mice induced higher proportions of TFH cells and germinal center (GC) B cells following immunization than were seen in wild type mice. Treatment with the PPARγ agonist pioglitazone significantly reduced TFH cell responses in female mice while pioglitazone and estradiol (E2) co-treatment ameliorated TFH cells and GC responses in male mice. E2 treatment significantly enhanced PPARγ expression in male T cells, while T cell activation in the estrus but not in the diestrus stage of the menstrual cycle of females was inhibited by pioglitazone, suggesting that an estrogen-sufficient environment is important for PPARγ-mediated T cell regulation. These results demonstrate gender-based differences in sensitivities of PPARγ in TFH responses. These findings suggest that appropriate function of PPARγ is required in the regulation of female GC responses and that therapeutic strategies for autoimmune diseases using PPARγ agonists need to be tailored accordingly. PMID:27335315

  19. From idealistic helper to enterprising learner: critical reflections on personal development through experiences from Afghanistan.

    PubMed

    Wickford, Jenny; Rosberg, Susanne

    2012-05-01

    There is little written about the cultural, social, and ethical challenges encountered by physiotherapists engaging in development work. This article takes a critical perspective on what it means to engage in development work as an expatriate physiotherapist, through a self-critical reflection on experiences from Afghanistan. The field notes from an ethnographic study of a development project conducted in Afghanistan were analysed to explore the transformative process of personal and professional development of the development worker. The critical reflective process entailed a change in meaning perspective, described as a shift from the position of an Idealistic Helper to an Enterprising Learner. Of importance in this process were "disorienting dilemmas" that challenged personal perceptions. Critical reflection over such dilemmas led to deeper understanding facilitating the process of change. The essential lesson learned is that the baseline for understanding others is an understanding of one's own meaning perspectives and manner of participation in relation to others and their context. The insights gained have implications for physiotherapists working in development contexts, for other development workers, and for physiotherapists working with patients in clinical practice in a nondevelopment context. Exploring how to collaborate in development contexts could be done using reflective groups with expatriate and local physiotherapists and/or patients. This could lead to greater understanding of oneself, each other, and the local context.

  20. Attenuation of AMPK signaling by ROQUIN promotes T follicular helper cell formation

    PubMed Central

    Ramiscal, Roybel R; Parish, Ian A; Lee-Young, Robert S; Babon, Jeffrey J; Blagih, Julianna; Pratama, Alvin; Martin, Jaime; Hawley, Naomi; Cappello, Jean Y; Nieto, Pablo F; Ellyard, Julia I; Kershaw, Nadia J; Sweet, Rebecca A; Goodnow, Christopher C; Jones, Russell G; Febbraio, Mark A; Vinuesa, Carola G; Athanasopoulos, Vicki

    2015-01-01

    T follicular helper cells (Tfh) are critical for the longevity and quality of antibody-mediated protection against infection. Yet few signaling pathways have been identified to be unique solely to Tfh development. ROQUIN is a post-transcriptional repressor of T cells, acting through its ROQ domain to destabilize mRNA targets important for Th1, Th17, and Tfh biology. Here, we report that ROQUIN has a paradoxical function on Tfh differentiation mediated by its RING domain: mice with a T cell-specific deletion of the ROQUIN RING domain have unchanged Th1, Th2, Th17, and Tregs during a T-dependent response but show a profoundly defective antigen-specific Tfh compartment. ROQUIN RING signaling directly antagonized the catalytic α1 subunit of adenosine monophosphate-activated protein kinase (AMPK), a central stress-responsive regulator of cellular metabolism and mTOR signaling, which is known to facilitate T-dependent humoral immunity. We therefore unexpectedly uncover a ROQUIN–AMPK metabolic signaling nexus essential for selectively promoting Tfh responses. DOI: http://dx.doi.org/10.7554/eLife.08698.001 PMID:26496200

  1. The transcriptional coactivator Bob1 promotes the development of follicular T helper cells via Bcl6.

    PubMed

    Stauss, Dennis; Brunner, Cornelia; Berberich-Siebelt, Friederike; Höpken, Uta E; Lipp, Martin; Müller, Gerd

    2016-04-15

    Follicular T helper (Tfh) cells are key regulators of the germinal center reaction and long-term humoral immunity. Tfh cell differentiation requires the sustained expression of the transcriptional repressor Bcl6; however, its regulation in CD4(+)T cells is incompletely understood. Here, we report that the transcriptional coactivator Bob1, encoded by thePou2af1gene, promotes Bcl6 expression and Tfh cell development. We found that Bob1 together with the octamer transcription factors Oct1/Oct2 can directly bind to and transactivate theBcl6andBtlapromoters. Mixed bone marrow chimeras revealed that Bob1 is required for the expression of normal levels of Bcl6 andBTLA, thereby controlling the pool size and composition of the Tfh compartment in a T cell-intrinsic manner. Our data indicate that T cell-expressed Bob1 is directly involved in Tfh cell differentiation and required for mounting normal T cell-dependent B-cell responses.

  2. AIRE expressing marginal zone dendritic cells balances adaptive immunity and T-follicular helper cell recruitment.

    PubMed

    Lindmark, Evelina; Chen, Yunying; Georgoudaki, Anna-Maria; Dudziak, Diana; Lindh, Emma; Adams, William C; Loré, Karin; Winqvist, Ola; Chambers, Benedict J; Karlsson, Mikael C I

    2013-05-01

    Autoimmune polyendocrine syndrome Type I (APS I) results in multiple endocrine organ destruction and is caused by mutations in the Autoimmune regulator gene (AIRE). In the thymic stroma, cells expressing the AIRE gene dictate T cell education and central tolerance. Although this function is the most studied, AIRE is also expressed in the periphery in DCs and stromal cells. Still, how AIRE regulated transcription modifies cell behaviour in the periphery is largely unknown. Here we show that AIRE is specifically expressed by 33D1(+) DCs and dictates the fate of antibody secreting cell movement within the spleen. We also found that AIRE expressing 33D1(+) DCs expresses self-antigens as exemplified by the hallmark gene insulin. Also, as evidence for a regulatory function, absence of Aire in 33D1(+) DCs led to reduced levels of the chemokine CXCL12 and increased co-stimulatory properties. This resulted in altered activation and recruitment of T-follicular helper cells and germinal centre B cells. The altered balance leads to a change of the early response to a T cell-dependent antigen in Aire(-/-) mice. These findings add to the understanding of how specific DC subtypes regulate the early responses during T cell-dependent antibody responses within the spleen and further define the role of AIRE in the periphery as regulator of self-antigen expression and lymphocyte migration.

  3. Reversibility of T helper 1 and 2 populations is lost after long-term stimulation

    PubMed Central

    1996-01-01

    Commitment of T helper 1 (Th1) or Th2 populations developing during an immune response to a pathogen, or an inappropriate immune response to an allergen or autoantigen, may determine the difference between health and chronic disease. We show that strongly polarized Th1 and Th2 populations assessed by immunoassay are heterogeneous using flow cytometry to detect single cells producing interferon gamma (IFN-gamma) and interleukin 4 (IL-4). Th1 populations arising after 1 wk of stimulation in IL-12 plus anti-IL-4 antibodies could convert to Th2 cells when restimulated in IL-4. Th2 populations resulting from stimulation for 1 wk in IL-4 could give rise to Th1 cells upon restimulation in IL-12 plus anti-IL-4. In contrast, the cytokine profiles of long-term Th1 and Th2 populations arising originally from repeated stimulation in IL-12 or IL-4 appeared more homogeneous and were not reversible, although IL-4 dramatically reduced the number of IFN-gamma-producing Th1 cells. This may explain previous reports that Th1 cells can be converted to Th2 cells. PMID:8642294

  4. From idealistic helper to enterprising learner: critical reflections on personal development through experiences from Afghanistan.

    PubMed

    Wickford, Jenny; Rosberg, Susanne

    2012-05-01

    There is little written about the cultural, social, and ethical challenges encountered by physiotherapists engaging in development work. This article takes a critical perspective on what it means to engage in development work as an expatriate physiotherapist, through a self-critical reflection on experiences from Afghanistan. The field notes from an ethnographic study of a development project conducted in Afghanistan were analysed to explore the transformative process of personal and professional development of the development worker. The critical reflective process entailed a change in meaning perspective, described as a shift from the position of an Idealistic Helper to an Enterprising Learner. Of importance in this process were "disorienting dilemmas" that challenged personal perceptions. Critical reflection over such dilemmas led to deeper understanding facilitating the process of change. The essential lesson learned is that the baseline for understanding others is an understanding of one's own meaning perspectives and manner of participation in relation to others and their context. The insights gained have implications for physiotherapists working in development contexts, for other development workers, and for physiotherapists working with patients in clinical practice in a nondevelopment context. Exploring how to collaborate in development contexts could be done using reflective groups with expatriate and local physiotherapists and/or patients. This could lead to greater understanding of oneself, each other, and the local context. PMID:22047471

  5. Site-1 protease is essential for endochondral bone formation in mice

    PubMed Central

    Patra, Debabrata; Xing, Xiaoyun; Davies, Sherri; Bryan, Jennifer; Franz, Carl; Hunziker, Ernst B.; Sandell, Linda J.

    2007-01-01

    Site-1 protease (S1P) has an essential function in the conversion of latent, membrane-bound transcription factors to their free, active form. In mammals, abundant expression of S1P in chondrocytes suggests an involvement in chondrocyte function. To determine the requirement of S1P in cartilage and bone development, we have created cartilage-specific S1P knockout mice (S1Pcko). S1Pcko mice exhibit chondrodysplasia and a complete lack of endochondral ossification even though Runx2 expression, Indian hedgehog signaling, and osteoblastogenesis is intact. However, there is a substantial increase in chondrocyte apoptosis in the cartilage of S1Pcko mice. Extraction of type II collagen is substantially lower from S1Pcko cartilage. In S1Pcko mice, the collagen network is disorganized and collagen becomes entrapped in chondrocytes. Ultrastructural analysis reveals that the endoplasmic reticulum (ER) in S1Pcko chondrocytes is engorged and fragmented in a manner characteristic of severe ER stress. These data suggest that S1P activity is necessary for a specialized ER stress response required by chondrocytes for the genesis of normal cartilage and thus endochondral ossification. PMID:18025304

  6. Zymogen Activation and Subcellular Activity of Subtilisin Kexin Isozyme 1/Site 1 Protease*

    PubMed Central

    da Palma, Joel Ramos; Burri, Dominique Julien; Oppliger, Joël; Salamina, Marco; Cendron, Laura; de Laureto, Patrizia Polverino; Seidah, Nabil Georges; Kunz, Stefan; Pasquato, Antonella

    2014-01-01

    The proprotein convertase subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P) plays crucial roles in cellular homeostatic functions and is hijacked by pathogenic viruses for the processing of their envelope glycoproteins. Zymogen activation of SKI-1/S1P involves sequential autocatalytic processing of its N-terminal prodomain at sites B′/B followed by the herein newly identified C′/C sites. We found that SKI-1/S1P autoprocessing results in intermediates whose catalytic domain remains associated with prodomain fragments of different lengths. In contrast to other zymogen proprotein convertases, all incompletely matured intermediates of SKI-1/S1P showed full catalytic activity toward cellular substrates, whereas optimal cleavage of viral glycoproteins depended on B′/B processing. Incompletely matured forms of SKI-1/S1P further process cellular and viral substrates in distinct subcellular compartments. Using a cell-based sensor for SKI-1/S1P activity, we found that 9 amino acid residues at the cleavage site (P1–P8) and P1′ are necessary and sufficient to define the subcellular location of processing and to determine to what extent processing of a substrate depends on SKI-1/S1P maturation. In sum, our study reveals novel and unexpected features of SKI-1/S1P zymogen activation and subcellular specificity of activity toward cellular and pathogen-derived substrates. PMID:25378398

  7. Site 1 field testing for cooling-water treatment. Final report

    SciTech Connect

    Litherland, S.T.; Owen, M.L.; Scholl, F.A.; Kamas, J.W.; Nassos, P.A.

    1985-06-01

    The Electric Power Research Institute is sponsoring a three phase research project to develop a design and operating methodology for recirculating cooling water systems at high concentration factors. To expand the available data base for cooling water systems at high concentration factors, a portable field test unit (FTU) has been designed and fabricated for operation at sites with different makeup water qualities. For a ten month period during 1981, the FTU was operated at the first site, Comanche Generating Station in Pueblo, Colorado. During the field testing, several cooling water treatment options were used to increase the concentration factor for operating the FTU. These water treatment options included: (1) sulfuric acid addition for alkalinity control; (2) lime-soda makeup softening; (3) lime-soda sidestream softening; (4) combined lime-soda makeup and sidestream softening; and (5) inhibitor addition for gypsum scale control. The purpose of this report is to present a detailed discussion of all Site 1 field test activities, including FTU operation and data interpretation and analyses. 11 refs., 68 figs., 70 tabs.

  8. Disorders of B cells and helper T cells in the pathogenesis of the immunoglobulin deficiency of patients with ataxia telangiectasia.

    PubMed Central

    Waldmann, T A; Broder, S; Goldman, C K; Frost, K; Korsmeyer, S J; Medici, M A

    1983-01-01

    The pathogenesis of the immunoglobulin deficiency of 20 patients with ataxia telangiectasia was studied using an in vitro immunoglobulin biosynthesis system. 10 patients had no detectable IgA in their serum as assessed by radial diffusion in agar and 3 had a reduced serum IgA concentration. The peripheral blood mononuclear cells of 17 of the patients and 17 normal controls were cultured with pokeweed mitogen for 12 d and the immunoglobulin in the supernatants measured. The immunoglobulin synthesis was below the lower limit of the normal 95% confidence interval for IgM in 5 patients, for IgG in 8, and for IgA in 14. The mononuclear cells from 9 of the 10 patients with a serum IgA concentration less than 0.1 mg/ml failed to synthesize IgA in vitro. None of the patients manifested excessive suppressor cell activity. All patients had reduced but measurable helper T cell activity for immunoglobulin synthesis by co-cultured normal pokeweed mitogen-stimulated B cells (geometric mean 22% of normal). Furthermore, the addition of normal irradiated T cells to patient peripheral blood mononuclear cells led to an augmentation of IgM synthesis in 15 of 17 and to increased IgG synthesis in 9 of the 17 patients studied, including 9 of the 12 patients who had synthesized IgG before the addition of the irradiated T cells. In addition, IgA synthesis was increased in all eight patients examined that had serum IgA concentrations greater than 0.1 mg/ml. These studies suggest that a helper T cell defect contributes to the diminished immunoglobulin synthesis. However, a helper T cell defect does not appear to be the sole cause since there was no IgA synthesis by the peripheral blood mononuclear cells of 9 of the 10 patients with a profoundly reduced serum IgA even when co-cultured with normal T cells. Furthermore, the cells of the nine patients with profoundly reduced IgA levels examined also failed to produce IgA when stimulated with the relatively helper T cell-independent polyclonal

  9. [THE STANDARD VALUES OF SUB-POPULATIONS OF T-HELPERS OF DIFFERENT LEVEL OF DIFFERENTIATION IN PERIPHERAL BLOOD].

    PubMed

    Kudryavtsev, I V; Serebryakova, M K; Totolyan, A A

    2016-03-01

    The study was carried out to develop standard indicators of relative and absolute content of main populations of T-helpers in peripheral blood of conditionally healthy donors. The examination was implemented to sampling of 52 healthy individuals (29 males and 23 females) aged 18-65 years (median is 30 years). The multicolor cytofluorimetric analysis was applied using panel of following antibodies: CD45RA-FITC, CD62L-PE, CCR4-PerCP/Cy5.5; CCR6-PE/Cy7, CXCR3-APC, CD3-APC-AF750, CD4-Pacific Blue and CXCR5-Brilliant Violet 510TM. The T-helpers 1 were distributed in populations of cells with phenotypes CXCR5-CXCR3+CCR6-CCR4-, also containing Th9, and CXCR5-CXCR3+CCR6+CCR4- referred as Thl/Thl7. The Th2 were detected an the basis of availability of CCR4 at the absence of all other chemokin receptors. The Thi7, besides Thl/Thi7 mentioned above, were detected in composition of CXCR5-CXCR3-CCR6+CCR4- and CXCR5-CXCR3-CCR6+CCR4+. The last population also contained Th22. The follicular Th which expressed at their surface CXCR5, formed six cellular populations with following phenotypes: CXCR5+CXCR3-CCR6-CCR4- (Tfh/Tfh2), CXCR5+CXCR3-CCR6-CCR4+ (Tfh2), CXCR5+CXCR3-CCR6+CCR4- (Tfh17), CXCR5+CXCR3-CCR6+CCR4+ (Tfh17), CXCR5+CXCR3+CCR6-CCR4- (Tfh1) and CXCR5+CXCR3+CCR6+CCR4- (Tfh1/Tfh17). The relative and absolute content of T-helpers of mentioned phenotypes was established both within the framework of total population CD3+CD4+ of lymphocytes and among "naive" T-helpers (CD45RA-CD62L+), T-helpers of central (CD45RA-CD62L+) and effector (CD45RA- CD62L-) memory and also "terminal-differentiated" CD45RA-positive cells of effector memory with phenotype CD45RA+CD62L-. The study results can be applied as standard indicators under diagnostic of pathologic conditions of immune system. PMID:27506110

  10. TIGIT-positive circulating follicular helper T cells display robust B-cell help functions: potential role in sickle cell alloimmunization.

    PubMed

    Godefroy, Emmanuelle; Zhong, Hui; Pham, Petra; Friedman, David; Yazdanbakhsh, Karina

    2015-11-01

    T follicular helper cells are the main CD4(+) T cells specialized in supporting B-cell responses, but their role in driving transfusion-associated alloimmunization is not fully characterized. Reports of T follicular helper subsets displaying various markers and functional activities underscore the need for better characterization/identification of markers with defined functions. Here we show that a previously unidentified subset of human circulating T follicular helper cells expressing TIGIT, the T-cell immunoreceptor with Ig and immunoreceptor tyrosine-based inhibitory domains, exhibit strong B-cell help functions. Compared to the subset lacking the receptor, T follicular helper cells expressing this receptor up-regulated co-stimulatory molecules and produced higher levels of interleukins (IL-21 and IL-4) critical for promoting B-cell activation/differentiation. Furthermore, this subset was more efficient at inducing the differentiation of B cells into plasmablasts and promoting immunoglobulin G production. Blocking antibodies abrogated the B-cell help properties of receptor-expressing T follicular helper cells, consistent with the key role of this molecule in T follicular helper-associated responses. Importantly, in chronically transfused patients with sickle cell anemia, we identified functional differences of this subset between alloimmunized and non-alloimmunized patients. Altogether, these studies suggest that expression of the T-cell immunoreceptor with Ig and immunoreceptor tyro-sine-based inhibitory domains not only represents a novel circulating T follicular helper biomarker, but is also functional and promotes strong B-cell help and ensuing immunoglobulin G production. These findings open the way to defining new diagnostic and therapeutic strategies in modulating humoral responses in alloimmunization, and possibly vaccination, autoimmunity and immune deficiencies.

  11. An evaluation of three-dimensional sensors for the extravehicular activity helper/retreiver

    NASA Technical Reports Server (NTRS)

    Magee, Michael

    1993-01-01

    The Extravehicular Activity Retriever/Helper (EVAHR) is a robotic device currently under development at the NASA Johnson Space Center that is designed to fetch objects or to assist in retrieving an astronaut who may have become inadvertently de-tethered. The EVAHR will be required to exhibit a high degree of intelligent autonomous operation and will base much of its reasoning upon information obtained from one or more three-dimensional sensors that it will carry and control. At the highest level of visual cognition and reasoning, the EVAHR will be required to detect objects, recognize them, and estimate their spatial orientation and location. The recognition phase and estimation of spatial pose will depend on the ability of the vision system to reliably extract geometric features of the objects such as whether the surface topologies observed are planar or curved and the spatial relationships between the component surfaces. In order to achieve these tasks, accurate sensing of the operational environment and objects in the environment will therefore be critical. The qualitative and quantitative results of empirical studies of three sensors that are capable of providing three-dimensional information to the EVAHR, but using completely different hardware approaches are documented. The first of these devices is a phase shift laser with an effective operating range (ambiguity interval) of approximately 15 meters. The second sensor is a laser triangulation system designed to operate at much closer range and to provide higher resolution images. The third sensor is a dual camera stereo imaging system from which range images can also be obtained. The remainder of the report characterizes the strengths and weaknesses of each of these systems relative to quality of data extracted and how different object characteristics affect sensor operation.

  12. Changes in Follicular Helper T Cells in Idiopathic Thrombocytopenic Purpura Patients

    PubMed Central

    Xie, Jue; Cui, Dawei; Liu, Yan; Jin, Jie; Tong, Hongyan; Wang, Lei; Ruan, Guoxiang; Lu, Yun; Yuan, Huiming

    2015-01-01

    Background: Idiopathic thrombocytopenic purpura (ITP) is a primary autoimmune disease with a decreased platelet count caused by platelet destruction mediated mainly by platelet antibodies. T follicular helper (TFH) cells have demonstrated important roles in autoimmune diseases. The aim of this study is to explore the might role of TFH cells in the patients of ITP. Methods: Twenty-three ITP patients and 12 healthy controls (HC) were enrolled in this study. The frequency of circulating TFH cells in both the patients and HC was analyzed by flow cytometry. Serum interleukin (IL)-21 and IL-6 levels were measured using ELISA, and platelet antibodies were tested using a solid phase technique. Additionally, IL-21, IL-6, Bcl-6 and c-Maf mRNA expressions in peripheral blood mononuclear cells (PBMCs) were detected using real-time PCR. Results: The percentages of circulating CXCR5+ CD4+TFH cells with ICOShigh or PD-1high expression were significantly higher in the ITP patients than in the HC. Moreover, the frequencies of circulating CXCR5+ CD4+TFH cells with inducible costimulator (ICOS)high or programmed death-1 (PD-1)high expression were notably higher in ITP with platelet-antibody-positive ( ITP (+) ) patients than in ITP with platelet-antibody-negative ( ITP (-) ) patients and HC, as were the serum IL-21 and IL-6 levels (significant). Moreover, a positive correlation was found between the CXCR5+CD4+TFH cells with ICOShigh or PD-1high expression and the serum IL-21 levels of ITP (+) patients. Additionally, the mRNA expression levels of IL-21, IL-6, Bcl-6 and c-Maf were significantly increased in ITP patients, especially in ITP (+) patients. Conclusions: This study demonstrated TFH cells and effector molecules might play an important role in the pathogenesis of ITP, which are possible therapeutic targets in ITP patients. PMID:25561904

  13. Tim-3 identifies exhausted follicular helper T cells in breast cancer patients.

    PubMed

    Zhu, Shiguang; Lin, Jun; Qiao, Guangdong; Wang, Xingmiao; Xu, Yanping

    2016-09-01

    Breast cancer is the most common cancer diagnosed in women worldwide. Although a series of treatment options have improved the overall 5-year survival rate to 90%, individual responses still vary from patient to patient. New evidence suggested that the infiltration of CXCL13-expressing CD4(+) follicular helper cells (Tfh) in breast tumor predicted better survival. Here, we examined the regulation of Tfh function in breast cancer patients in depth. We found that the frequencies of circulating Tfh cells were not altered in breast cancer patients compared to healthy controls. However, the expression of PD-1 and Tim-3 in Tfh cells was significantly elevated in breast cancer patients. Interestingly, we observed a preferential upregulation of PD-1 in Tim-3(+) Tfh cells compared to Tim-3(-) Tfh cells. Coexpression of PD-1 and Tim-3 is typically a hallmark of functional exhaustion in chronic virus infections and tumor. To examine whether Tim-3(+) identifies exhausted Tfh cells, we stimulated Tfh cells with anti-CD3/CD28, and found that Tim-3(+) T cells expressed reduced frequencies of chemokine CXCL13 and cytokine interleukin 21 (IL-21), and contained fewer proliferating cells, than Tim-3(-) Tfh cells. Compared to those cocultured with Tim-3(-) Tfh cells, naive B cells cocultured with Tim-3(+) Tfh cells resulted in significantly less IgM, IgG and IgA production after 12 day incubation, demonstrating a reduction in Tim-3(+) Tfh-mediated B cell help. Moreover, the frequencies of Tim-3(+) Tfh cells in resected breast tumor were further upregulated than autologous blood, suggesting a participation of Tim-3(+) Tfh cells in tumor physiology. Overall, the data presented here provided new insight in the regulation of Tfh cells in breast cancer patients.

  14. Do Helper T Cell Subtypes in Lymphocytic Thyroiditis Play a Role in the Antitumor Effect?

    PubMed Central

    Yang, Seok Woo; Kang, Seong-Ho; Kim, Kyung Rae; Choi, In Hong; Chang, Hang Seok; Oh, Young Lyun; Hong, Soon Won

    2016-01-01

    Background Papillary thyroid carcinoma (PTC) is frequently accompanied by lymphocytic thyroiditis (LT). Some reports claim that Hashimoto’s thyroiditis (the clinical form of LT) enhances the likelihood of PTC; however, others suggest that LT has antitumor activity. This study was aimed to find out the relationship between the patterns of helper T cell (Th) cytokines in thyroid tissue of PTC with or without LT and the clinicopathological manifestation of PTC. Methods Fresh surgical samples of PTC with (13 cases) or without (10 cases) LT were used. The prognostic parameters (tumor size, extra-thyroidal extension of PTC, and lymph node metastasis) were analyzed. The mRNA levels of two subtypes of Th cytokines, Th1 (tumor necrosis factor α [TNF-α], interferon γ [IFN-γ ], and interleukin [IL] 2) and Th2 (IL-4 and IL-10), were analyzed. Because most PTC cases were microcarcinomas and recent cases without clinical follow-up, negative or faint p27 immunoreactivity was used as a surrogate marker for lymph node metastasis. Results PTC with LT cases showed significantly higher expression of TNF-α (p = .043), IFN-γ (p < .010), IL-4 (p = .015) than those without LT cases. Although the data were not statistically significant, all analyzed cytokines (except for IL-4) were highly expressed in the cases with higher expression of p27 surrogate marker. Conclusions These results indicate that mixed Th1 (TNF-α, IFN-γ , and IL-2) and Th2 (IL-10) immunity might play a role in the antitumor effect in terms of lymph node metastasis. PMID:27681413

  15. Pancreatic Transduction by Helper-Dependent Adenoviral Vectors via Intraductal Delivery

    PubMed Central

    Morró, Meritxell; Teichenne, Joan; Jimenez, Veronica; Kratzer, Ramona; Marletta, Serena; Maggioni, Luca; Mallol, Cristina; Ruberte, Jesus; Kochanek, Stefan; Bosch, Fatima

    2014-01-01

    Abstract Pancreatic gene transfer could be useful to treat several diseases, such as diabetes mellitus, cystic fibrosis, chronic pancreatitis, or pancreatic cancer. Helper-dependent adenoviral vectors (HDAds) are promising tools for gene therapy because of their large cloning capacity, high levels of transgene expression, and long-term persistence in immunocompetent animals. Nevertheless, the ability of HDAds to transduce the pancreas in vivo has not been investigated yet. Here, we have generated HDAds carrying pancreas-specific expression cassettes, that is, driven either by the elastase or insulin promoter, using a novel and convenient plasmid family and homologous recombination in bacteria. These HDAds were delivered to the pancreas of immunocompetent mice via intrapancreatic duct injection. HDAds, encoding a CMV-GFP reporter cassette, were able to transduce acinar and islet cells, but transgene expression was lost 15 days postinjection in correlation with severe lymphocytic infiltration. When HDAds encoding GFP under the control of the specific elastase promoter were used, expression was detected in acinar cells, but similarly, the expression almost disappeared 30 days postinjection and lymphocytic infiltration was also observed. In contrast, long-term transgene expression (>8 months) was achieved with HDAds carrying the insulin promoter and the secretable alkaline phosphatase as the reporter gene. Notably, transduction of the liver, the preferred target for adenovirus, was minimal by this route of delivery. These data indicate that HDAds could be used for pancreatic gene therapy but that selection of the expression cassette is of critical importance to achieve long-term expression of the transgene in this tissue. PMID:25046147

  16. Progress and prospects: gene therapy for genetic diseases with helper-dependent adenoviral vectors

    PubMed Central

    Brunetti-Pierri, N; Ng, P

    2013-01-01

    Preclinical studies in small and large animal models using helper-dependent adenoviral vectors (HDAds) have generated promising results for the treatment of genetic diseases. However, clinical translation is complicated by the dose-dependent, capsid-mediated acute toxic response following systemic vector injection. With the advancements in vectorology, a better understanding of vector-mediated toxicity, and improved delivery methods, HDAds may emerge as an important vector for gene therapy of genetic diseases and this report highlights recent progress and prospects in this field. In briefProgressHDAds provide stable, long-term transgene expression in small and large animal models without chronic toxicity for liver-directed gene therapy.High vector doses are required for efficient hepatocyte transduction by systemic administration.Strategies to improve the therapeutic index of HDAd are available or currently under investigation for liver-directed gene therapy.High-efficiency pulmonary transduction and clinically relevant end points can be achieved delivering HDAd in conjunction with tight junction opening agents for CF gene therapy.HDAd delivered with an intracorporeal nebulizing catheter results in high-efficiency transduction of the respiratory epithelium in large animals.Encouraging results have been obtained with HDAd for brain- and muscle-directed gene therapy in animal models.ProspectsA better understanding of the acute innate response will provide new targets for pharmacological blockade to improve the therapeutic index of the vector.Further optimization of preferential liver targeting by HDAd through balloon catheter delivery has the potential of providing a clinically attractive method of vector delivery.Further assessment of Ad PEGylation and modulation of the liver fenestrations may provide attractive strategies to increase the therapeutic index of the vector.Capsid modification to increase the affinity of Ad for hepatocytes has the potential to improve

  17. Lipocalin-2 exacerbates psoriasiform skin inflammation by augmenting T-helper 17 response.

    PubMed

    Hau, Carren S; Kanda, Naoko; Tada, Yayoi; Shibata, Sayaka; Uozaki, Hiroshi; Fukusato, Toshio; Sato, Shinichi; Watanabe, Shinichi

    2016-07-01

    Lipocalin-2 (LCN2) is an antimicrobial protein and adipokine associated with insulin resistance, obesity and atherosclerotic disease. Psoriasis is a T-helper (Th)1/Th17-mediated, chronic inflammatory dermatosis related to metabolic syndromes and serum LCN2 levels are elevated in psoriatic patients. We examined the in vivo effects of LCN2 on topical imiquimod (IMQ)-induced psoriasiform skin in BALB/c mice and in vitro on human keratinocytes (KC). Clinically, i.p. injected LCN2 exacerbated erythema and scaling in IMQ-treated murine skin compared with phosphate-buffered saline injection alone, and it augmented interleukin (IL)-17A, IL-17F, IL-22, IL-23p19, IL-12p40, CCL20, tumor necrosis factor-α, chemokine (C-X-C motif) ligand (CXCL)1, CXCL2, DEFB4, DEFB14, LCN2 and S100A7 mRNA levels of IMQ-treated murine skin while it did not increase the mRNA levels of interferon-γ, IL-12p35 or CXCL10. LCN2 in synergy with IL-17 increased mRNA levels of CCL20, LCN2 and DEFB4A but not of CXCL10 in human KC in vitro. These results suggest that LCN2 enhances the expression of Th17 cytokines/chemokines and antimicrobial peptides in murine IMQ-treated psoriatic skin and KC. LCN2 may potentiate the development of psoriasis via the enhancement of Th17- and antimicrobial peptide-mediated inflammation. PMID:26702876

  18. Reversible Reprogramming of Circulating Memory T Follicular Helper Cell Function during Chronic HIV Infection.

    PubMed

    Cubas, Rafael; van Grevenynghe, Julien; Wills, Saintedym; Kardava, Lela; Santich, Brian H; Buckner, Clarisa M; Muir, Roshell; Tardif, Virginie; Nichols, Carmen; Procopio, Francesco; He, Zhong; Metcalf, Talibah; Ghneim, Khader; Locci, Michela; Ancuta, Petronella; Routy, Jean-Pierre; Trautmann, Lydie; Li, Yuxing; McDermott, Adrian B; Koup, Rick A; Petrovas, Constantinos; Migueles, Steven A; Connors, Mark; Tomaras, Georgia D; Moir, Susan; Crotty, Shane; Haddad, Elias K

    2015-12-15

    Despite the overwhelming benefits of antiretroviral therapy (ART) in curtailing viral load in HIV-infected individuals, ART does not fully restore cellular and humoral immunity. HIV-infected individuals under ART show reduced responses to vaccination and infections and are unable to mount an effective antiviral immune response upon ART cessation. Many factors contribute to these defects, including persistent inflammation, especially in lymphoid tissues, where T follicular helper (Tfh) cells instruct and help B cells launch an effective humoral immune response. In this study we investigated the phenotype and function of circulating memory Tfh cells as a surrogate of Tfh cells in lymph nodes and found significant impairment of this cell population in chronically HIV-infected individuals, leading to reduced B cell responses. We further show that these aberrant memory Tfh cells exhibit an IL-2-responsive gene signature and are more polarized toward a Th1 phenotype. Treatment of functional memory Tfh cells with IL-2 was able to recapitulate the detrimental reprogramming. Importantly, this defect was reversible, as interfering with the IL-2 signaling pathway helped reverse the abnormal differentiation and improved Ab responses. Thus, reversible reprogramming of memory Tfh cells in HIV-infected individuals could be used to enhance Ab responses. Altered microenvironmental conditions in lymphoid tissues leading to altered Tfh cell differentiation could provide one explanation for the poor responsiveness of HIV-infected individuals to new Ags. This explanation has important implications for the development of therapeutic interventions to enhance HIV- and vaccine-mediated Ab responses in patients under ART.

  19. Elevated Urinary T Helper 1 Chemokine Levels in Newly Diagnosed Hypertensive Obese Children

    PubMed Central

    Övünç Hacıhamdioğlu, Duygu; Zeybek, Cengiz; Gök, Faysal; Pekel, Aysel; Muşabak, Uğur

    2015-01-01

    Objective: Increasing evidence suggests that T helper (Th) cells play a significant role in the pathogenesis of hypertension. The aim of this study was to evaluate the effect of obesity and anti-hypertensive treatment on urinary Th1 chemokines. Methods: The study groups consisted of three types of patients: hypertensive obese, healthy, and non-hypertensive obese. Pre-treatment and post-treatment samples of the hypertensive obese group and one sample from the other two groups were evaluated for urinary chemokine: regulated on activation, normal T cell expressed and secreted (RANTES), interferon-gamma-inducible protein 10 (IP10), and monokine induced by interferon-gamma (MIG). In the hypertensive obese group, urine microalbumin: creatinine ratio was examined before and after treatment. We recommended lifestyle changes to all patients. Captopril was started in those who could not be controlled with lifestyle changes and those who had stage 2 hypertension. Results: Twenty-four hypertensive obese (mean age 13.1), 27 healthy (mean age 11.2) and 22 non-hypertensive obese (mean age 11.5) children were investigated. The pre-treatment urine albumin: creatinine ratio was positively correlated with pre-treatment MIG levels (r=0.41, p<0.05). RANTES was significantly higher in the pre-treatment hypertensive and non-hypertensive obese group than in the controls. The urinary IP10 and MIG levels were higher in the pre-treatment hypertensive obese group than in the non-hypertensive obese. Comparison of the pre- and post-treatment values indicated significant decreases in RANTES, IP10, and MIG levels in the hypertensive obese group (p<0.05). Conclusion: Th1 cells could be activated in obese hypertensive children before the onset of clinical indicators of target organ damage. Urinary RANTES seemed to be affected by both hypertension and obesity, and urinary IP10 and MIG seemed to be affected predominantly by hypertension. PMID:26831550

  20. T helper type 17 pathway suppression by appendicitis and appendectomy protects against colitis.

    PubMed

    Cheluvappa, R; Luo, A S; Grimm, M C

    2014-02-01

    Appendicitis followed by appendectomy (AA) at a young age protects against inflammatory bowel disease (IBD). We wanted to characterize the role of the T helper type 17 (Th17) system involved in this protective effect. AA was performed on 5-week-old male BALB/c mice and distal-colon samples were harvested. Mice with two laparotomies each served as sham-sham (SS) controls. RNA was extracted from four individual colonic samples per group (AA and SS groups) and each sample microarray-analysed and reverse transcription-polymerase chain reaction (RT-PCR)-validated. Gene-set enrichment analysis (GSEA) showed that the Th17 recruitment factor gene CCL20 was significantly suppressed at both 3 days post-AA and 28 days post-AA. Although Th17 cell development differentiation factor genes TGF-β2 and TGF-β3 were significantly up-regulated 3 days post-AA, GSEA 28 days post-AA showed that AA down-regulated 29 gene-sets associated with TGF-β1, TGF-β2 and TGF-β3 in contrast to none up-regulated with any of these genes. GSEA showed substantial down-regulation of gene-sets associated with Th17 lymphocyte recruitment, differentiation, activation and cytokine expression in the AA group 28 days post-AA. We conclude that Th17-system cytokines are kept under control by AA via down-regulation of proinflammatory CCL20, a rapid down-regulation of pro-Th17 cell differentiation genes TGF-β2 and TGF-β3, suppression of RORC-associated gene-sets, increased protective STAT1 expression and suppression of 81 'pro-Th17' system gene-sets. AA suppresses the Th17 pathway leading to colitis amelioration. Further characterization of Th17-associated genes and biological pathways will assist in the development of better therapeutic approaches in IBD management. PMID:24666024

  1. ADENO-ASSOCIATED SATELLITE VIRUS INTERFERENCE WITH THE REPLICATION OF ITS HELPER ADENOVIRUS

    PubMed Central

    Parks, Wade P.; Casazza, Anna M.; Alcott, Judith; Melnick, Joseph L.

    1968-01-01

    Adeno-associated satellite virus type 4 interferes with the replication of its helper adenovirus. No interferon-like soluble substance could be detected in satellite-infected cultures and other DNA- and RNA-containing viruses were not inhibited by coinfection with satellite virus under conditions which reduced adenovirus yields by more than 90% in monkey cells. Altering the concentration of adenovirus in the presence of constant amounts of satellite resulted in a constant degree of interference over a wide range of adenovirus inocula and suggested that adenovirus concentration was not a significant factor in the observed interference. The interference with adenovirus replication was abolished by pretreating satellite preparations with specific antiserum, ultraviolet light or heating at 80°C for 30 min. This suggested that infectious satellite virus mediated the interference. Satellite virus concentration was found to be a determinant of interference and studies indicated that the amount of interference with adenovirus was directly proportional to the concentration of satellite virus. 8 hr after adenovirus infection, the replication of adenovirus was no longer sensitive to satellite interference. This was true even though the satellite virus was enhanced as effectively as if the cells were infected simultaneously with both viruses. Interference with adenovirus infectivity was accompanied by reduced yields of complement-fixing antigen and of virus particles which suggested that satellite virus interfered with the formation and not the function of adenovirus products. When cells were infected either with adenovirus alone or with adenovirus plus satellite, the same proportion of cells plated as adenovirus infectious centers. However, the number of plaque-forming units of adenovirus formed per cell in the satellite-infected cultures was reduced by approximately 90%, the same magnitude of reduction noted in whole cultures coinfected with satellite and adenovirus. This

  2. The good, the bad and the dubious: VHELIBS, a validation helper for ligands and binding sites

    PubMed Central

    2013-01-01

    Background Many Protein Data Bank (PDB) users assume that the deposited structural models are of high quality but forget that these models are derived from the interpretation of experimental data. The accuracy of atom coordinates is not homogeneous between models or throughout the same model. To avoid basing a research project on a flawed model, we present a tool for assessing the quality of ligands and binding sites in crystallographic models from the PDB. Results The Validation HElper for LIgands and Binding Sites (VHELIBS) is software that aims to ease the validation of binding site and ligand coordinates for non-crystallographers (i.e., users with little or no crystallography knowledge). Using a convenient graphical user interface, it allows one to check how ligand and binding site coordinates fit to the electron density map. VHELIBS can use models from either the PDB or the PDB_REDO databank of re-refined and re-built crystallographic models. The user can specify threshold values for a series of properties related to the fit of coordinates to electron density (Real Space R, Real Space Correlation Coefficient and average occupancy are used by default). VHELIBS will automatically classify residues and ligands as Good, Dubious or Bad based on the specified limits. The user is also able to visually check the quality of the fit of residues and ligands to the electron density map and reclassify them if needed. Conclusions VHELIBS allows inexperienced users to examine the binding site and the ligand coordinates in relation to the experimental data. This is an important step to evaluate models for their fitness for drug discovery purposes such as structure-based pharmacophore development and protein-ligand docking experiments. PMID:23895374

  3. Reversible Reprogramming of Circulating Memory T Follicular Helper Cell Function during Chronic HIV Infection

    PubMed Central

    Cubas, Rafael; van Grevenynghe, Julien; Wills, Saintedym; Kardava, Lela; Santich, Brian H.; Buckner, Clarisa M.; Muir, Roshell; Tardif, Virginie; Nichols, Carmen; Procopio, Francesco; He, Zhong; Metcalf, Talibah; Ghneim, Khader; Locci, Michela; Ancuta, Petronella; Routy, Jean-Pierre; Trautmann, Lydie; Li, Yuxing; McDermott, Adrian B.; Koup, Rick A.; Petrovas, Constantinos; Migueles, Steven A.; Connors, Mark; Tomaras, Georgia D.; Moir, Susan; Crotty, Shane

    2015-01-01

    Despite the overwhelming benefits of antiretroviral therapy (ART) in curtailing viral load in HIV-infected individuals, ART does not fully restore cellular and humoral immunity. HIV-infected individuals under ART show reduced responses to vaccination and infections and are unable to mount an effective antiviral immune response upon ART cessation. Many factors contribute to these defects, including persistent inflammation, especially in lymphoid tissues, where T follicular helper (Tfh) cells instruct and help B cells launch an effective humoral immune response. In this study we investigated the phenotype and function of circulating memory Tfh cells as a surrogate of Tfh cells in lymph nodes and found significant impairment of this cell population in chronically HIV-infected individuals, leading to reduced B cell responses. We further show that these aberrant memory Tfh cells exhibit an IL-2–responsive gene signature and are more polarized toward a Th1 phenotype. Treatment of functional memory Tfh cells with IL-2 was able to recapitulate the detrimental reprogramming. Importantly, this defect was reversible, as interfering with the IL-2 signaling pathway helped reverse the abnormal differentiation and improved Ab responses. Thus, reversible reprogramming of memory Tfh cells in HIV-infected individuals could be used to enhance Ab responses. Altered microenvironmental conditions in lymphoid tissues leading to altered Tfh cell differentiation could provide one explanation for the poor responsiveness of HIV-infected individuals to new Ags. This explanation has important implications for the development of therapeutic interventions to enhance HIV- and vaccine-mediated Ab responses in patients under ART. PMID:26546609

  4. Hybrid T-Helper Cells: Stabilizing the Moderate Center in a Polarized System

    PubMed Central

    Huang, Sui

    2013-01-01

    Polarization of cell phenotypes, a common strategy to achieve cell type diversity in metazoa, results from binary cell-fate decisions in the branching pedigree of development. Such “either-or” fate decisions are controlled by two opposing cell fate-determining transcription factors. Each of the two distinct “master regulators” promotes differentiation of its respective sister lineage. But they also suppress one other, leading to their mutually exclusive expression in the two ensuing lineages. Thus, promiscuous coexistence of the antagonist regulators in the same cell, the hallmark of the common “undecided” progenitor of two sister lineages, is considered unstable. This antagonism ensures robust polarization into two discretely distinct cell types. But now the immune system's T-helper (Th) cells and their two canonical subtypes, Th1 and Th2 cells, tell a different story, as revealed in three papers recently published in PLOS Biology. The intermediate state that co-expresses the two opposing master regulators of the Th1 and Th2 subtypes, T-bet and Gata3, is highly stable and is not necessarily an undecided precursor. Instead, the Th1/Th2 hybrid cell is a robust new type with properties of both Th1 and Th2 cells. These hybrid cells are functionally active and possess the benefit of moderation: self-limitation of effector T cell function to prevent excessive inflammation, a permanent risk in host defense that can cause tissue damage or autoimmunity. Gene regulatory network analysis suggests that stabilization of the intermediate center in a polarizing system can be achieved by minor tweaking of the architecture of the mutual suppression gene circuit, and thus is a design option readily available to evolution. PMID:23976879

  5. Impaired Phenotype and Function of T Follicular Helper Cells in HIV-1-Infected Children Receiving ART

    PubMed Central

    Bekele, Yonas; Amu, Sylvie; Bobosha, Kidist; Lantto, Rebecka; Nilsson, Anna; Endale, Birtukan; Gebre, Meseret; Aseffa, Abraham; Rethi, Bence; Howe, Rawleigh; Chiodi, Francesca

    2015-01-01

    Abstract T follicular helper (Tfh) cells are important components in development of specific humoral immune responses; whether the number and biology of Tfh cells is impaired in HIV-1-infected children is not yet studied. The frequency, phenotype, and function of Tfh cells and B cells were determined in blood of HIV-1-infected children receiving antiretroviral therapy (ART) and age-matched controls. Flow cytometry was used to characterize the frequency of Tfh cells and B cell subsets. Cytokine expression was measured after in vitro activation of Tfh cells. A reduced frequency of memory Tfh cells (P < 0.001) was identified in HIV-1-infected children and, on these cells, a reduced expression of programmed death-1 (PD-1) and inducible T cell costimulator (ICOS) (P < 0.001 and P < 0.01). Upon activation, the capacity of Tfh cells to express IL-4, an important cytokine for B cell function, was impaired in HIV-1-infected children. B cell subpopulations in HIV-1-infected children displayed significant differences from the control group: the frequency of resting memory (RM) B cells was reduced (P < 0.01) whereas the frequency of exhausted memory B cells increased (P < 0.001). Interestingly, the decline of RM cells correlated with the reduction of memory Tfh cells (P = 0.02). Our study shows that function and phenotype of Tfh cells, pivotal cells for establishment of adaptive B cell responses, are impaired during HIV-1 infection in children. A consistent reduction of memory Tfh cells is associated with declined frequencies of RM B cells, creating a novel link between dysfunctional features of these cell types, major players in establishment of humoral immunity. PMID:26166114

  6. The Secreted Form of Transmembrane Protein 98 Promotes the Differentiation of T Helper 1 Cells

    PubMed Central

    Fu, Weiwei; Cheng, Yingying; Zhang, Yanfei; Mo, Xiaoning; Li, Ting; Liu, Yuanfeng; Wang, Pingzhang; Pan, Wen; Chen, Yingyu; Xue, Yintong; Ma, Dalong; Zhang, Yu

    2015-01-01

    Cytokines mediate the interaction of immune cells. Discovery of novel potential cytokines is of great value for both basic research and clinical application. In this study, we identified a novel immune-related molecule, transmembrane protein 98 (TMEM98), through a high-throughput screening platform for novel potential cytokines at a genome-wide level using the strategy of immunogenomics. So far, there is no characteristic and immune-related functional report about it. In this study, we demonstrate that TMEM98 exists as a type II transmembrane protein both in the ectopically and endogenously expressed systems. Interestingly, TMEM98 could also be secreted through exosomes. Moreover, the native secreted form of TMEM98 could be detected in the supernatants of activated human peripheral blood mononuclear cells and mouse CD4+ T cells. Further expression profile analysis showed TMEM98 was upregulated during the activation and differentiation of T helper (Th) 1 cells. Function analysis showed that eukaryotic recombinant TMEM98 (rTMEM98) promoted the differentiation of Th1 cells under both antigen-nonspecific and antigen-specific Th1-skewing conditions. These findings were further confirmed in vivo as prokaryotic rTMEM98 administration significantly increased antigen-specific IFN-γ production and serum antigen-specific IgG2a in the methylated bovine serum albumin-induced delayed-type hypersensitivity model. Overall, these observations emphasize the characteristics and essential roles of TMEM98 for the first time and will be helpful in further understanding the development of Th1 cells. PMID:25946230

  7. Identification of helper T cell epitopes of dengue virus E-protein.

    PubMed

    Leclerc, C; Dériaud, E; Megret, F; Briand, J P; Van Regenmortel, M H; Deubel, V

    1993-05-01

    The T cell proliferative response to dengue 2 (Jamaica) E-glycoprotein (495 amino acids) was analyzed in vitro using either killed virus or E-protein fragments or synthetic peptides. Inactivated dengue virus stimulated dengue-specific lymph node (LN) CD4+T cell proliferation in BALB/c (H-2d), C3H (H-2k) and DBA/1 (H-2q) but not in C57BL/6 (H-2b) mice. Moreover, LN cells from dengue-virus primed BALB/c mice proliferated in vitro in response to three purified non-overlapping E-protein fragments expressed in E. coli as polypeptides fused to trpE (f22-205, f267-354, f366-424). To further determine T cell epitopes in the E-protein, synthetic peptides were selected using prediction algorithms for T cell epitopes. Highest proliferative responses were obtained after in vitro exposure of virus-primed LN cells to peptides p135-157, p270-298, p295-307 and p337-359. Peptide p59-78 was able to induce specific B and T cell responses in peptide-primed mice of H-2d, H-2q and H-2k haplotypes. Two peptides p59-78 corresponding to two dengue (Jamaica and Sri Lanka) isolates and differing only at position 71 cross-reacted at the B but not at the T cell level in H-2b mice. This analysis of murine T helper cell response to dengue E-protein may be of use in dengue subunit vaccine design.

  8. Retinoic Acid Attenuates Ileitis by Restoring the Balance between T-Helper 17 and T

    PubMed Central

    Collins, Colm B.; Aherne, Carol M.; Kominsky, Douglas; McNamee, Eóin N.; Lebsack, Matthew D.P.; Eltzschig, Holger; Jedlicka, Paul; Rivera-Nieves, Jesús

    2013-01-01

    Background & Aims Retinoic acid (RA), produced by intestinal epithelial cells (IECs) and dendritic cells (DCs) and regulated by transforming growth factor (TGF)-β, controls the enteric immune response by activating regulatory T (Treg) cells and preventing activation of T-helper (Th)17 cells Methods We studied the roles of RA in mice that overproduce tumor necrosis factor (TNF) and develop chronic ileitis (TNFΔARE mice). We assessed the frequency and function of CD103+ DCs and Th17 and Treg cells by flow cytometry; we measured expression of cytokines and retinaldehyde dehydrogenase (RALDH) enzymes in ileum samples, DCs, and IECs by real-time PCR. We quantified RA by electrochemical analysis and examined the effect of RA supplementation on TNF-induced ileitis using histologic, co-culture, and suppression assays and flow cytometry Results Numbers of CD103+ DCs decreased in the inflamed ilea of mice with chronic disease; RA synthetic machinery (RALDH1,2) was downregulated. Nevertheless, the proportion of CD4+, CD25+, FoxP3+ Treg cells increased, indicating an alternate source for RA. IECs responded to reduced levels of RA by upregulating RALDH3 in vivo and in vitro. Net tissue levels of RA levels remained lower in TNFΔARE than wild-type mice, indicating that epithelial up-regulation of RALDH3 could not maintain adequate concentrations of RA, probably because of loss of IEC mass. RA supplementation significantly attenuated disease by increasing the number and function of CD103+ DCs and Treg cells and reducing Th17 cells Conclusions Reduced levels of RA appear to induce IEC to upregulate synthesis of RA. RA supplementation attenuates ileitis through its effects on CD103+ DCs and Treg and Th17 cells. RA supplementation might used to treat patients with Crohn's disease PMID:22027263

  9. FTY720 ameliorates oxazolone colitis in mice by directly affecting T helper type 2 functions.

    PubMed

    Daniel, Carolin; Sartory, Nico A; Zahn, Nadine; Schmidt, Ronald; Geisslinger, Gerd; Radeke, Heinfried H; Stein, Jurgen M

    2007-07-01

    The sphingosine-1-phosphate analogue FTY720 is known to alter migration and homing of lymphocytes via sphingosine-1-phosphate receptors. However, several studies indicate that its mode of action is more complex and that FTY720 may also directly influence cytokine effector functions. Therefore, we studied the effect of FTY720 in T helper type (Th2)-mediated oxazolone-induced colitis in mice. Following rectal oxazolone instillation, Th2 cells producing IL-13 induce a progressive colitis resembling human ulcerative colitis. A rectal enema of oxazolone [90 mg/kg body weight] was applied to BALB/c mice. FTY720 was administered i.p. from day 0 to 3 or from day 3 to 5 following the instillation of the haptenating agent. Assessment of severity of colitis was performed daily. FTY720 plasma levels were detected using LC-MS/MS-analysis. Colon tissue was analyzed macroscopically and microscopically, myeloperoxidase activity as well as cytokine levels of lamina propria CD4(+) T-cells and T1/ST2 expression were determined. Treatment with FTY720 prominently reduced the clinical and histopathologic severity of oxazolone-induced colitis, abrogating body weight loss, diarrhea, and macroscopic and microscopic intestinal inflammation. The therapeutic effects of FTY720 were associated with a prominent reduction of the key effector Th2 cytokines IL-13, IL-4 and IL-5. Strikingly, FTY720 inhibited GATA3 and T1/ST2 expression which represent highly relevant markers for Th2 differentiation and Th2 effector function, respectively. Our data provide the first evidence that FTY720 exhibits beneficial prophylactic as well as therapeutic effects in Th2-mediated experimental colitis by directly affecting Th2 cytokine profiles probably by reducing T1/ST2, thus offering a new auspicious therapeutic instrument for the treatment of human ulcerative colitis.

  10. Induction of CD4+ Regulatory and Polarized Effector/helper T Cells by Dendritic Cells

    PubMed Central

    2016-01-01

    Dendritic cells (DCs) are considered to play major roles during the induction of T cell immune responses as well as the maintenance of T cell tolerance. Naive CD4+ T cells have been shown to respond with high plasticity to signals inducing their polarization into effector/helper or regulatory T cells. Data obtained from in vitro generated bone-marrow (BM)-derived DCs as well as genetic mouse models revealed an important but not exclusive role of DCs in shaping CD4+ T cell responses. Besides the specialization of some conventional DC subsets for the induction of polarized immunity, also the maturation stage, activation of specialized transcription factors and the cytokine production of DCs have major impact on CD4+ T cells. Since in vitro generated BM-DCs show a high diversity to shape CD4+ T cells and their high similarity to monocyte-derived DCs in vivo, this review reports data mainly on BM-DCs in this process and only touches the roles of transcription factors or of DC subsets, which have been discussed elsewhere. Here, recent findings on 1) the conversion of naive into anergic and further into Foxp3− regulatory T cells (Treg) by immature DCs, 2) the role of RelB in steady state migratory DCs (ssmDCs) for conversion of naive T cells into Foxp3+ Treg, 3) the DC maturation signature for polarized Th2 cell induction and 4) the DC source of IL-12 for Th1 induction are discussed. PMID:26937228

  11. Identification of canine helper T-cell epitopes from the fusion protein of canine distemper virus

    PubMed Central

    Ghosh, Souravi; Walker, John; Jackson, David C

    2001-01-01

    The fusion protein of canine distemper virus (CDV-F), a 662 amino-acid envelope protein, was used as the target molecule for identification of canine T helper (Th) epitopes. A library of 94 peptides, each 17 residues in length overlapping by 10 residues and covering the entire sequence of CDV-F, was screened using a lymphocyte proliferation assay with peripheral blood mononuclear cells (PBMC) obtained from dogs inoculated with canine distemper virus (CDV) vaccine. Initially we observed low and inconsistent proliferation of PBMC in response to these peptides, even when using cells obtained from dogs that had received multiple doses of CDV. Subsequently, the use of expanded cell populations derived by in vitro stimulation of canine PBMC with pools of peptides allowed the identification of a number of putative canine Th-epitopes within the protein sequence of CDV-F. There were two major clusters of Th-epitopes identified close to the cleavage site of the F0 fusion protein, while some others were scattered in both the F1 and F2 fragments of the protein. Some of these peptides, in particular peptide 35 (p35), were stimulatory in dogs of different breeds and ages. The identification of such promiscuous canine Th-epitopes encouraged us to assemble p35 in tandem with luteinising hormone releasing hormone (LHRH) a 10 amino-acid residue synthetic peptide representing a B-cell epitope which alone induces no antibody in dogs. The totally synthetic immunogen was able to induce the production of very high titres of antibodies against LHRH in all dogs tested. These results indicate that p35 could be an ideal candidate for use as a Th-epitope for use in outbred dogs. PMID:11576221

  12. The role of helper lipids in the intracellular disposition and transfection efficiency of niosome formulations for gene delivery to retinal pigment epithelial cells.

    PubMed

    Ojeda, Edilberto; Puras, Gustavo; Agirre, Mireia; Zarate, Jon; Grijalvo, Santiago; Eritja, Ramon; DiGiacomo, Luca; Caracciolo, Giulio; Pedraz, Jose-Luis

    2016-04-30

    In this work, we carried out a comparative study of four different niosome formulations based on the same cationic lipid and non-ionic tensoactive. The niosomes prepared by oil-in-water emulsion technique (o/w) only differed in the helper lipid composition: squalene, cholesterol, squalane or no helper lipid. Niosomes and nioplexes elaborated upon the addition of pCMS-EGFP reporter plasmid were characterized in terms of size, zeta potential and polydispersity index. The capacity of the niosomes to condense, release and protect the DNA against enzymatic degradation was evaluated by agarose gel electrophoresis. In vitro experiments were carried out to evaluate transfection efficiency and cell viability in retinal pigment epithelial cells. Moreover, uptake and intracellular trafficking studies were performed to further understand the role of the helper lipids in the transfection process. Interestingly, among all tested formulations, niosomes elaborated with squalene as helper lipid were the most efficient transfecting cells. Such transfection efficiency could be attributed to their higher cellular uptake and the particular entry pathways used, where macropinocytosis pathway and lysosomal release played an important role. Therefore, these results suggest that helper lipid composition is a crucial step to be considered in the design of niosome formulation for retinal gene delivery applications since clearly modulates the cellular uptake, internalization mechanism and consequently, the final transfection efficiency.

  13. An Adenovirus Type 5 Mutant with the Preterminal Protein Gene Deleted Efficiently Provides Helper Functions for the Production of Recombinant Adeno-Associated Virus

    PubMed Central

    Maxwell, Ian H.; Maxwell, Francoise; Schaack, Jerome

    1998-01-01

    Production of recombinant adeno-associated virus (rAAV) requires helper functions that have routinely been provided by infection of the producer cells with adenovirus. Complete removal and/or inactivation of progeny adenovirus, present in such rAAV preparations, presents significant difficulty. Here, we report that an adenovirus type 5 (Ad5) mutant with the preterminal protein (pTP) gene deleted can provide helper function for the growth of rAAV. At high multiplicity, Ad5dl308ΔpTP was as efficient as the phenotypically wild-type Ad5dl309 in permitting growth of rAAV. Use of Ad5dl308ΔpTP, which is incapable of replication in the absence of complementation for pTP, as a helper avoids the need to remove contaminating adenovirus infectious activity by heat inactivation or by purification. Comparison of the transducing ability of rAAV generated with either Ad5dl308ΔpTP or Ad5dl309 as a helper demonstrated that the heat inactivation protocol generally used does not remove all of the helper Ad5dl309 function. PMID:9733887

  14. Probing the Strength of Infants' Preference for Helpers over Hinderers: Two Replication Attempts of Hamlin and Wynn (2011)

    PubMed Central

    Volein, Agnes; Karap, Zsuzsanna; Csibra, Gergely

    2015-01-01

    Several studies indicate that infants prefer individuals who act prosocially over those who act antisocially toward unrelated third parties. In the present study, we focused on a paradigm published by Kiley Hamlin and Karen Wynn in 2011. In this study, infants were habituated to a live puppet show in which a protagonist tried to open a box to retrieve a toy placed inside. The protagonist was either helped by a second puppet (the “Helper”), or hindered by a third puppet (the “Hinderer”). At test, infants were presented with the Helper and the Hinderer, and encouraged to reach for one of them. In the original study, 75% of 9-month-olds selected the Helper, arguably demonstrating a preference for prosocial over antisocial individuals. We conducted two studies with the aim of replicating this result. Each attempt was performed by a different group of experimenters. Study 1 followed the methods of the published study as faithfully as possible. Study 2 introduced slight modifications to the stimuli and the procedure following the guidelines generously provided by Kiley Hamlin and her collaborators. Yet, in our replication attempts, 9-month-olds’ preference for helpers over hinderers did not differ significantly from chance (62.5% and 50%, respectively, in Studies 1 and 2). Two types of factors could explain why our results differed from those of Hamlin and Wynn: minor methodological dissimilarities (in procedure, materials, or the population tested), or the effect size being smaller than originally assumed. We conclude that fine methodological details that are crucial to infants’ success in this task need to be identified to ensure the replicability of the original result. PMID:26565412

  15. Immunoregulatory subsets of the T helper and T suppressor cell populations in homosexual men with chronic unexplained lymphadenopathy.

    PubMed Central

    Nicholson, J K; McDougal, J S; Spira, T J; Cross, G D; Jones, B M; Reinherz, E L

    1984-01-01

    Unexplained, generalized lymphadenopathy in homosexual men, which can be a prodrome to the acquired immunodeficiency syndrome, is associated with impaired cell-mediated immunity, a low ratio of T helper-inducer to T suppressor-cytotoxic cells (defined by the T4 and T8 monoclonal antibodies), and hypergammaglobulinemia. We performed double-marker studies on T cells by using a panel of monoclonal antibodies (Ia, T17, TQ1, and Leu-8), which reportedly detect activation or functional subsets of the T4 and T8 T cell populations. The T4:TQ1- or T4:Leu-8- subset, which is the major helper subset for B cell responses, is normally represented in lymphadenopathy patients. A depression in the reciprocal subset, T4:TQ1+ or T4:Leu-8+, accounts for the T4 T cell defect. Similarly, the TQ1 and Leu-8 markers delineate the abnormality of T8 T cells: the T8:TQ1- or T8:Leu-8- subset is elevated, whereas the T8:TQ1+ or T8:Leu-8+ subset is normally represented. We found no evidence of excessive activation of T4 T cells by using the T17 or Ia monoclonal antibodies. We did find an overall increase in Ia-positive T cells; however, this was due to increased T8:Ia+ cells. In functional studies, immunoglobulin production induced by pokeweed was subnormal. Most lymphadenopathy patients had normal T helper cell function when combined with normal B cells. The dampened pokeweed responses could be partially explained by depression of the T4:TQ1+ (or T4:Leu-8+) subset (which has minor help-associated function) and/or greater than expected suppression. However, subnormal pokeweed responses could not be totally explained by immunoregulatory T cell abnormalities because we also found an intrinsic defect in the B cell responses of lymphadenopathy patients. PMID:6228564

  16. CD4+ T-helper lymphocyte responses against Babesia bigemina rhoptry-associated protein I.

    PubMed Central

    Rodríguez, S D; Palmer, G H; McElwain, T F; McGuire, T C; Ruef, B J; Chitko-McKown, M G; Brown, W C

    1996-01-01

    A multigene family of 58- to 60-kDa proteins, which are designated rhoptry-associated protein 1 (RAP-1) and which come from the parasites Babesia bigemina and Babesia bovis, is a target for vaccine development. The presence of multiple gene copies and conserved sequences and epitopes of RAP-1 implies that these proteins are functionally important for the survival of these parasites. Furthermore, it was previously shown that B. bigemina RAP-1 induced partial protection against challenge infection. However, the lack of correlation between protective immunity to B. bigemina infection and antibody titers against a merozoite surface-exposed, neutralization-sensitive epitope of B. bigemina RAP-1 indicated the potential importance of RAP-1-specific T helper (Th) cells in the observed protection. To begin to understand the mechanism of RAP-1-induced protective immunity, RAP-1-specific T-cell responses were characterized in cattle. Vigorous and sustained proliferative responses of peripheral blood mononuclear cells from native RAP-1-immunized cattle were observed. The anamnestic response in immunized cattle was specific for B. bigemina RAP-1 and predominantly comprised CD4+ T cells, which upon cloning expressed type 1 cytokine mRNA profiles and high levels of gamma interferon protein. The T cells responded to both native and recombinant forms of RAP-1, indicating the potential to use recombinant protein or epitopes derived therefrom as a vaccine that could evoke specific recall responses after exposure to natural infection. The differential responses of peripheral blood mononuclear cells and seven Th-cell clones derived from RAP-1-immunized cattle to different Central American strains of B. bigemina indicated the presence of at least one conserved and one variable Th-cell epitope. The lack of response to B. bovis RAP-1 indicated that a strictly conserved 14-amino-acid peptide shared by the two babesial species was not immunogenic for Th cells in these experiments. However

  17. Novel function of complement C3d as an autologous helper T-cell target.

    PubMed

    Knopf, Paul M; Rivera, Daniel S; Hai, Si-Han; McMurry, Julie; Martin, William; De Groot, Anne S

    2008-01-01

    The C3d fragment of complement component C3 has been shown to enhance immune responses to antigens that lack T-cell epitopes such as bacterial polysaccharides. C3d binds to the B-cell complement receptor 2 (CR2 or CD21); this binding serves as a co-activation signal to the B cell when the polysaccharide antigen portion binds simultaneously to the B-cell receptor (surface Ig). Bringing together receptor-associated signal transduction molecules CD19 and Igalpha/beta, respectively, results in a lower threshold of activation. Paradoxically, C3d has also been shown to enhance antibody titers in the CD21 knockout (KO) mouse model as well as increase Th1 and Th2 cytokine secretion, suggesting that that an auxiliary CR2-independent pathway of immune activation may exist. We hypothesized that in addition to its molecular adjuvant property that enhances signal 1 during B-cell activation (co-signal 1), C3d also contains T-cell epitopes that are able to stimulate autoreactive C3d peptide-specific helper T cells which we term 'co-signal 2'. Using the EpiMatrix T-cell epitope-mapping algorithm, we identified 11 putative T-cell epitopes in C3d, a very high epitope density for a 302 amino-acid sequence. Eight of these epitope candidates were synthesized and shown to bind a variety of class II HLA-DR molecules of different haplotypes, and to stimulate C3d peptide-specific T cells to secrete pro-inflammatory cytokines in vitro. Further, we demonstrate a C3d-peptide specific increase in CD4(+) intracellular IFN-gamma(+) T cells in peripheral blood mononuclear cells (PBMCs) exposed to C3d peptides in vitro. We believe that the discovery of these autologous T cells autoreactive for C3d provides evidence supporting the 'co-signal 2' hypothesis and may offer a novel explanation of the CD21 KO paradox. PMID:18180801

  18. IL-23 Contributes to Control of Chronic Helicobacter Pylori Infection and the Development of T Helper Responses in a Mouse Model1

    PubMed Central

    Horvath, Dennis J.; Washington, M. Kay; Cope, Vicki A.; Algood, Holly M. Scott

    2012-01-01

    The immune response to Helicobacter pylori involves a mixed T helper-1, T helper-2, and T helper-17 response. It has been suggested that T helper cells contribute to the gastric inflammatory response during infection, and that T helper 1 (Th1) and T helper 17 (Th17) subsets may be required for control of H. pylori colonization in the stomach. The relative contributions of these subsets to gastritis and control of infection are still under investigation. IL-23 plays a role in stabilizing and expanding Th17 cell cytokine expression. Expression of IL-23, which is induced in dendritic cells and macrophages following co-culture with H. pylori, has also been reported to increase during H. pylori infection in humans and animal models. To investigate the role of IL-23 in H. pylori, we infected IL-23p19 deficient mice (IL-23−/−) and wild-type littermates with H. pylori strain SS1. At various time points post-infection, we assessed colonization, gastric inflammation, and cytokine profiles in the gastric tissue. Specifically, H. pylori-infected IL-23−/− mice have higher levels of H. pylori in their stomachs, significantly less chronic gastritis, and reduced expression of IL-17 and IFNγ compared to H. pylori-infected wild-type mice. While many of these differences were significant, the H. pylori infected IL-23−/− had mild increases in our measurements of disease severity. Our results indicate that IL-23 plays a role in the activation of the immune response and induction of gastritis in response to H. pylori by contributing to the control of infection and severity of gastritis. PMID:22566937

  19. Neural progenitor cell survival in mouse brain can be improved by co-transplantation of helper cells expressing bFGF under doxycycline control.

    PubMed

    Liang, Yajie; Ågren, Louise; Lyczek, Agatha; Walczak, Piotr; Bulte, Jeff W M

    2013-09-01

    Cell-based therapy of neurological disorders is hampered by poor survival of grafted neural progenitor cells (NPCs). We hypothesized that it is possible to enhance the survival of human NPCs (ReNcells) by co-transplantation of helper cells expressing basic fibroblast growth factor (bFGF) under control of doxycycline (Dox). 293 cells or C17.2 cells were transduced with a lentiviral vector encoding the fluorescent reporter mCherry and bFGF under tetracycline-regulated transgene expression (Tet-ON). The bFGF secretion level in the engineered helper cells was positively correlated with the dose of Dox (Pearson correlation test; r=0.95 and 0.99 for 293 and C17.2 cells, respectively). Using bioluminescence imaging (BLI) as readout for firefly luciferase-transduced NPC survival, the addition of both 293-bFGF and C17.2-bFGF helper cells was found to significantly improve cell survival up to 6-fold in vitro, while wild-type (WT, non-transduced) helper cells had no effect. Following co-transplantation of 293-bFGF or C17.2-bFGF cells in the striatum of Rag2(-/-) immunodeficient mice, in vivo human NPC survival could be significantly improved as compared to no helper cells or co-transplantation of WT cells for the first two days after co-transplantation. This enhancement of survival in C17.2-bFGF group was not achieved without Dox administration, indicating that the neuroprotective effect was specific for bFGF. The present results warrant further studies on the use of engineered helper cells, including those expressing other growth factors injected as mixed cell populations.

  20. T Regulatory and T Helper 17 Cells in Primary Sjögren's Syndrome: Facts and Perspectives

    PubMed Central

    Alunno, Alessia; Carubbi, Francesco; Bistoni, Onelia; Caterbi, Sara; Bartoloni, Elena; Mirabelli, Giulia; Cannarile, Francesca; Cipriani, Paola; Giacomelli, Roberto; Gerli, Roberto

    2015-01-01

    Historically, primary Sjögren's syndrome (pSS) was thought to be a T helper (h) 1 driven disease due to the predominance of CD4+T lymphocytes and their products in target organs and peripheral blood of patients. In the last decades, the identification of a number of T cell subsets, including Th17, T regulatory (Treg), and follicular helper T cells, challenged this long-standing paradigm and prompted to identify their role in pSS pathogenesis. In addition the impact of abnormal proinflammatory cytokine production, such as IL-6, IL-17, IL-22, and IL-23, has also attracted considerable attention. However, although several studies have been carried out in experimental models and patients with pSS, many aspects concerning the role of Treg cells and IL-17/Th17 cell system in pSS pathogenesis are not fully elucidated. In particular, the role played by different IL-17-producing T cell subsets as well as the effects of pharmacological therapies on Treg/Th17 cell balance represents an intriguing issue. The aim of this review article is to provide an overview of current knowledge on Treg cells and IL-17-producing T cells in pSS pathogenesis. We believe that these insights into pSS pathogenesis may provide the basis for successful therapeutic intervention in this disease. PMID:26060357

  1. Local T/B cooperation in inflamed tissues is supported by T follicular helper-like cells

    PubMed Central

    Vu Van, Dana; Beier, Katja C.; Pietzke, Lea-Jean; Al Baz, Maysun S.; Feist, Randi K.; Gurka, Stephanie; Hamelmann, Eckard; Kroczek, Richard A.; Hutloff, Andreas

    2016-01-01

    Autoimmune diseases and other inflammatory conditions are characterized by large lymphocytic tissue infiltrates in which T and B cells can be found in close contact. Here, using a murine airway inflammation model, we compare antigen-specific T and B cells in lung tissue versus lung-draining lymph node. In the lung we identify a B-cell population exhibiting a classical germinal centre phenotype without being organized into ectopic lymphoid tissue. By contrast, classical CXCR5+ Bcl-6+ T follicular helper cells are not present. Nevertheless, lung-infiltrating T cells exhibit follicular helper-like properties including the potential to provide help to naive B cells. The lung tissue is also a survival niche for memory T and B cells remaining in residual peribronchial infiltrates after resolution of inflammation. Collectively, this study shows the importance of T/B cooperation not only in lymph nodes but also in inflamed peripheral tissues for local antibody responses to infection and autoimmunity. PMID:26915335

  2. Reduced inflammation and improved airway expression using helper-dependent adenoviral vectors with a K18 promoter.

    PubMed

    Toietta, Gabriele; Koehler, David R; Finegold, Milton J; Lee, Brendan; Hu, Jim; Beaudet, Arthur L

    2003-05-01

    Efforts have been made to deliver transgenes to the airway epithelia of laboratory animals and humans to develop gene therapy for cystic fibrosis. These investigations have been disappointing due to combinations of transient and low-level gene expression, acute toxicity, and inflammation. We have developed new helper-dependent adenoviral vectors to deliver an epithelial cell-specific keratin 18 expression cassette driving the beta-galactosidase (beta-gal) or human alpha-fetoprotein (AFP) reporter genes. Following intranasal administration to mice, we found that the reporter genes were widely expressed in airway epithelial and submucosal cells, and secreted human AFP was also detectable in serum. In contrast to a first-generation adenoviral vector, inflammation was negligible at doses providing efficient transduction, and expression lasted longer than typically reported-up to 28 days with beta-gal and up to 15 weeks with human AFP. These results suggest that delivery to the airway of helper-dependent adenoviral vectors utilizing a tissue-specific promoter could be a significant advance in the development of gene therapy for cystic fibrosis. PMID:12718908

  3. CD26 Expression on T Helper Populations and sCD26 Serum Levels in Patients with Rheumatoid Arthritis

    PubMed Central

    Cordero, Oscar J.; Varela-Calviño, Rubén; López-González, Tania; Calviño-Sampedro, Cristina; Viñuela, Juan E.; Mouriño, Coral; Hernández-Rodríguez, Íñigo; Rodríguez-López, Marina; Aspe de la Iglesia, Bruno; Pego, José María

    2015-01-01

    We studied dipeptidyl peptidase IV (DPP-IV, CD26) expression in different T helper cells and serum soluble DPP-IV/sCD26 levels in rheumatoid arthritis (RA) patients, correlated these with disease activity score (DAS), and examined how they were affected by different therapies, conventional or biological (anti-TNF, anti-CD20 and anti-IL6R or Ig-CTLA4). The percentage of CD4+CD45R0+CD26- cells was greatly reduced in patients (up to 50%) when compared with healthy subjects. Three other subsets of CD4 cells, including a CD26high Th1-associated population, changed variably with therapies. Data from these subsets (frequency and staining density) significantly correlated with DAS28 or DAS28 components but different in each group of patients undergoing the different therapies. Th17 and Th22 subsets were implicated in RA as independent CCR4+ and CCR4- populations each, with distinct CD26 expression, and were targeted with varying efficiency by each therapy. Serum DPP-IV activity rather than sCD26 levels was lower in RA patients compared to healthy donors. DPP-IV and sCD26 serum levels were found related to specific T cell subsets but not to disease activity. We conclude that, according to their CD26 expression, different cell subsets could serve to monitor RA course, and an uncharacterized T helper CD26- subset, not targeted by therapies, should be monitored for early diagnosis. PMID:26177310

  4. A rapid Q-PCR titration protocol for adenovirus and helper-dependent adenovirus vectors that produces biologically relevant results.

    PubMed

    Gallaher, Sean D; Berk, Arnold J

    2013-09-01

    Adenoviruses are employed in the study of cellular processes and as expression vectors used in gene therapy. The success and reproducibility of these studies is dependent in part on having accurate and meaningful titers of replication competent and helper-dependent adenovirus stocks, which is problematic due to the use of varied and divergent titration protocols. Physical titration methods, which quantify the total number of viral particles, are used by many, but are poor at estimating activity. Biological titration methods, such as plaque assays, are more biologically relevant, but are time consuming and not applicable to helper-dependent gene therapy vectors. To address this, a protocol was developed called "infectious genome titration" in which viral DNA is isolated from the nuclei of cells ~3 h post-infection, and then quantified by Q-PCR. This approach ensures that only biologically active virions are counted as part of the titer determination. This approach is rapid, robust, sensitive, reproducible, and applicable to all forms of adenovirus. Unlike other Q-PCR-based methods, titers determined by this protocol are well correlated with biological activity.

  5. Biophysical characterization data of the artificial protein Octarellin V.1 and binding test with its X-ray helpers.

    PubMed

    Figueroa, Maximiliano; Vandenameele, Julie; Goormaghtigh, Erik; Valerio-Lepiniec, Marie; Minard, Philippe; Matagne, André; Van de Weerdt, Cécile

    2016-09-01

    The artificial protein Octarellin V.1 (http://dx.doi.org/10.1016/j.jsb.2016.05.004[1]) was obtained through a direct evolution process over the de novo designed Octarellin V (http://dx.doi.org/10.1016/S0022-2836(02)01206-8[2]). The protein has been characterized by circular dichroism and fluorescence techniques, in order to obtain data related to its thermo and chemical stability. Moreover, the data for the secondary structure content studied by circular dichroism and infra red techniques is reported for the Octarellin V and V.1. Two crystallization helpers, nanobodies (http://dx.doi.org/10.1038/nprot.2014.039[3]) and αRep (http://dx.doi.org/10.1016/j.jmb.2010.09.048[4]), have been used to create stable complexes. Here we present the data obtained of the binding characterization of the Octarellin V.1 with the crystallization helpers by isothermal titration calorimetry. PMID:27547801

  6. JAK inhibition induces silencing of T Helper cytokine secretion and a profound reduction in T regulatory cells.

    PubMed

    Keohane, Clodagh; Kordasti, Shahram; Seidl, Thomas; Perez Abellan, Pilar; Thomas, Nicholas S B; Harrison, Claire N; McLornan, Donal P; Mufti, Ghulam J

    2015-10-01

    CD4(+) T cells maintain cancer surveillance and immune tolerance. Chronic inflammation has been proposed as a driver of clonal evolution in myeloproliferative neoplasms (MPN), suggesting that T cells play an important role in their pathogenesis. Treatment with JAK inhibitors (JAKi) results in improvements in MPN-associated constitutional symptoms as well as reductions in splenomegaly. However, effects of JAKi on T cells in MPN are not well established and the baseline immune signature remains unclear. We investigated the frequency and function of CD4(+) T cell subsets in 50 MPN patients at baseline as well as during treatment with either ruxolitinib or fedratinib in a subset. We show that CD4(+)  CD127(low)  CD25(high)  FOXP3(+) T regulatory cells are reduced in MPN patients compared to healthy controls and that this decrease is even more pronounced following JAKi therapy. Moreover, we show that after 6 months of treatment the number of T helper (Th)-17 cells increased. We also describe a functional 'silencing' of T helper cells both in vivo and in vitro and a blockade of pro-inflammatory cytokines from these cells. This profound effect of JAKi on T cell function may underlay augmented rates of atypical infections that have been reported with use of these drugs.

  7. Regulated expression of human CD4 rescues helper T cell development in mice lacking expression of endogenous CD4.

    PubMed Central

    Killeen, N; Sawada, S; Littman, D R

    1993-01-01

    During T cell development, precursor thymocytes that co-express the CD4 and CD8 glycoproteins give rise to mature progeny expressing one of these molecules to the exclusion of the other. Continued expression of only CD4 is the hallmark of mature helper T cells, whereas cytotoxic T cells express CD8 and extinguish CD4. The differentiation program that generates the two T cell subsets is likely to be intimately tied to regulation of expression of these cell surface molecules. We now describe the use of a murine CD4 enhancer in the generation of transgenic mice expressing physiologic levels of human CD4. The transgene is appropriately regulated during T cell development and includes the necessary cis-acting sequences for extinguishing expression in the CD8 lineage. Furthermore, in mice whose endogenous CD4 gene is inactivated, the transgenic human CD4 mediates rescue of the CD4 lineage and restoration of normal helper cell functions. The generation of these mice exemplifies a general approach for developing reliable animal models for the human immune system. Images PMID:8467804

  8. Titrating T cell Epitopes within Self-Assembled Vaccines Optimizes CD4+ Helper T Cell and Antibody Outputs

    PubMed Central

    Chen, Jianjun; Verbus, Emily A.; Han, Huifang; Fridman, Arthur; McNeely, Tessie; Collier, Joel H.; Chong, Anita S.

    2014-01-01

    Epitope content plays a critical role in determining T cell and antibody responses to vaccines, biomaterials, and protein therapeutics, but its effects are nonlinear and difficult to isolate. Here, molecular self-assembly was used to build a vaccine with precise control over epitope content, in order to finely tune the magnitude and phenotype of T helper and antibody responses. Self-adjuvanting peptide nanofibers were formed by co-assembling a high-affinity universal CD4+ T cell epitope (PADRE) and a B cell epitope from Staphylococcus aureus at specifiable concentrations. Increasing the PADRE concentration from μM to mM elicited bell-shaped dose-responses that were unique to different T cell populations. Notably, the epitope ratios that maximized T follicular helper and antibody responses differed by an order of magnitude from those that maximized Th1 or Th2 responses. Thus, modular materials assembly provides a means of controlling epitope content and efficiently skewing the adaptive immune response in the absence of exogenous adjuvant; this approach may contribute to the development of improved vaccines and immunotherapies. PMID:24923735

  9. Titrating T-cell epitopes within self-assembled vaccines optimizes CD4+ helper T cell and antibody outputs.

    PubMed

    Pompano, Rebecca R; Chen, Jianjun; Verbus, Emily A; Han, Huifang; Fridman, Arthur; McNeely, Tessie; Collier, Joel H; Chong, Anita S

    2014-11-01

    Epitope content plays a critical role in determining T-cell and antibody responses to vaccines, biomaterials, and protein therapeutics, but its effects are nonlinear and difficult to isolate. Here, molecular self-assembly is used to build a vaccine with precise control over epitope content, in order to finely tune the magnitude and phenotype of T helper and antibody responses. Self-adjuvanting peptide nanofibers are formed by co-assembling a high-affinity universal CD4+ T-cell epitope (PADRE) and a B-cell epitope from Staphylococcus aureus at specifiable concentrations. Increasing the PADRE concentration from micromolar to millimolar elicited bell-shaped dose-responses that are unique to different T-cell populations. Notably, the epitope ratios that maximize T follicular helper and antibody responses differed by an order of magnitude from those that maximized Th1 or Th2 responses. Thus, modular materials assembly provides a means of controlling epitope content and efficiently skewing the adaptive immune response in the absence of exogenous adjuvant; this approach may contribute to the development of improved vaccines and immunotherapies.

  10. Different calcium influx characteristics upon Kv1.3 and IKCa1 potassium channel inhibition in T helper subsets.

    PubMed

    Orbán, Csaba; Bajnok, Anna; Vásárhelyi, Barna; Tulassay, Tivadar; Toldi, Gergely

    2014-07-01

    Functional imbalance between T helper subsets plays important role in the pathogenesis of autoimmune disorders. Transient increase of cytoplasmic calcium level, and sustention of negative membrane potential by voltage sensitive Kv1.3 and calcium-dependent IKCa1 potassium channels are essential for short-term lymphocyte activation, thus present possible target for selective immunomodulation. We aimed to investigate calcium influx sensitivity to the inhibition of potassium channels in the main T helper subsets. Peripheral blood from 11 healthy individuals was drawn and calcium influx kinetics following activation with phytohemagglutinin in Th1, Th2, Th17, and Treg cells were evaluated. Alteration of calcium influx induced by specific inhibitors of Kv1.3 and IKCa1 potassium channels, and the expression of Kv1.3 channels were also assessed. Highest cytoplasmic calcium concentration was observed in stimulated Th1 cells, while the lowest level was measured in Treg cells. In Th1 and Th17 cells, inhibition of both investigated potassium channels decreased calcium influx. In Th2 cells only the inhibitor of Kv1.3 channels, while in Treg cells none of the inhibitors had significant effect. Upon the inhibition of IKCa1 channels, short-term activation of proinflammatory cells was specifically decreased without affecting anti-inflammatory subsets, indicating that selective immunomodulation is possible in healthy individuals.

  11. Comparison of Systemic and Mucosal Immunization with Helper-Dependent Adenoviruses for Vaccination against Mucosal Challenge with SHIV

    PubMed Central

    Nehete, Bharti P.; Yang, Guojun; Buchl, Stephanie J.; Hanley, Patrick W.; Palmer, Donna; Montefiori, David C.; Ferrari, Guido; Ng, Philip; Sastry, K. Jagannadha; Barry, Michael A.

    2013-01-01

    Most HIV-1 infections are thought to occur at mucosal surfaces during sexual contact. It has been hypothesized that vaccines delivered at mucosal surfaces may mediate better protection against HIV-1 than vaccines that are delivered systemically. To test this, rhesus macaques were vaccinated by intramuscular (i.m.) or intravaginal (ivag.) routes with helper-dependent adenoviral (HD-Ad) vectors expressing HIV-1 envelope. Macaques were first immunized intranasally with species C Ad serotype 5 (Ad5) prior to serotype-switching with species C HD-Ad6, Ad1, Ad5, and Ad2 vectors expressing env followed by rectal challenge with CCR5-tropic SHIV-SF162P3. Vaccination by the systemic route generated stronger systemic CD8 T cell responses in PBMC, but weaker mucosal responses. Conversely, mucosal immunization generated stronger CD4 T cell central memory (Tcm) responses in the colon. Intramuscular immunization generated higher levels of env-binding antibodies, but neither produced neutralizing or cytotoxic antibodies. After mucosal SHIV challenge, both groups controlled SHIV better than control animals. However, more animals in the ivag. group had lower viral set points than in in the i.m. group. These data suggest mucosal vaccination may have improve protection against sexually-transmitted HIV. These data also demonstrate that helper-dependent Ad vaccines can mediate robust vaccine responses in the face of prior immunity to Ad5 and during four rounds of adenovirus vaccination. PMID:23844034

  12. Increased Frequency of T Follicular Helper Cells and Elevated Interleukin-27 Plasma Levels in Patients with Pemphigus

    PubMed Central

    Schmidt, Thomas; Seipelt, Maria; Tackenberg, Björn; Möbs, Christian; Ghoreschi, Kamran; Hertl, Michael; Eming, Rüdiger

    2016-01-01

    Pemphigus is an autoimmune disease in which IgG auto-antibodies (auto-ab) against the desmosomal cadherins desmoglein (Dsg) 3 and Dsg1 cause loss of epidermal keratinocyte adhesion. Aim of this study was to investigate cytokines derived from antigen-presenting cells (APC) and their relation to CD4+ T cell subpopulations and to the auto-ab response in pemphigus. In this regard, patients with pemphigus were compared to patients with myasthenia gravis (MG), an unrelated auto-ab–mediated autoimmune disease, and healthy controls. In pemphigus and MG, the plasma concentrations of the APC-derived immunomodulatory cytokine IL-27 were highly increased. Strikingly, IL-27 strongly correlated with Dsg-specific IgG auto-ab titers. T helper (Th) 17 cells were augmented in both pemphigus and MG patients while T follicular helper (Tfh) cells, which are essential in providing B cell help, were increased only in pemphigus along with increasing plasma concentrations of IL-21, a cytokine produced by Th17 and Tfh cells. Moreover, we could detect Dsg3-specific autoreactive T cells producing IL-21 upon ex vivo stimulation with Dsg3. These findings suggest that IL-27 and IL-21-producing T cells, are involved in the pathogenesis of pemphigus. The further characterization of IL-21-producing T cells and of the role of IL-27 will lead to a more defined understanding of the auto-ab response in pemphigus. PMID:26872212

  13. Dysbiosis of gut microbiota induced the disorder of helper T cells in influenza virus-infected mice.

    PubMed

    Yu, Bin; Dai, Cong-qi; Chen, Jia; Deng, Li; Wu, Xian-lin; Wu, Sha; Zhao, Chang-lin; Jiang, Zhen-you; Chen, Xiao-yin

    2015-01-01

    It is widely understood that commensal microbiota contributes to the maintenance of intestinal homeostasis through dynamic interactions with a body's immunity. And the immune regulation is important for the influenza vaccine's effectiveness after body injection, however, the mechanism between commensal microbiota and vaccine's effectiveness remains unknown. The impact that individual bacteria species have on the balance of the systemic immune system beyond the local intestinal mucosal tissues also remains less clear, and the related mechanism is still unknown. In this study, through the administration of various antibiotics, we examined the balance of helper T cell subsets in mice after inoculating them with the influenza virus and then, attempted to imitate the clinical practice in which patients are always prescribed with an antibiotic treatment in flu season. The data indicates that the mice in each group present differential immune responses in terms of the makeup of helper T cell subsets, although the Th17 cell activity seems to not be involved in the systemic immune modulation in the mice that are susceptible to the intervention of antibiotic. Th1, Th2, and anti-inflammatory regulatory T cells have been implicated in the contribution to the systemic immune response influenced by the antibiotic-induced dysbiosis. Thus we believe that the normal intestinal flora could maintain the immune balance and inhibit the inflammatory responses, which may be useful for clinical application to take intestinal flora into consideration when influenza vaccination was used. PMID:25874358

  14. Multifunctional Double-negative T Cells in Sooty Mangabeys Mediate T-helper Functions Irrespective of SIV Infection

    PubMed Central

    Micci, Luca; Gasper, Melanie A.; Ortiz, Alexandra M.; Else, James; Silvestri, Guido; Paiardini, Mirko; Aitchison, John D.; Sodora, Donald L.

    2013-01-01

    Studying SIV infection of natural host monkey species, such as sooty mangabeys, has provided insights into the immune changes associated with these nonprogressive infections. Mangabeys maintain immune health despite high viremia or the dramatic CD4 T cell depletion that can occur following multitropic SIV infection. Here we evaluate double-negative (DN)(CD3+CD4−CD8−) T cells that are resistant to SIV infection due to a lack of CD4 surface expression, for their potential to fulfill a role as helper T cells. We first determined that DN T cells are polyclonal and predominantly exhibit an effector memory phenotype (CD95+CD62L−). Microarray analysis of TCR (anti-CD3/CD28) stimulated DN T cells indicated that these cells are multifunctional and upregulate genes with marked similarity to CD4 T cells, such as immune genes associated with Th1 (IFNγ), Th2 (IL4, IL5, IL13, CD40L), Th17 (IL17, IL22) and TFH (IL21, ICOS, IL6) function, chemokines such as CXCL9 and CXCL10 and transcription factors known to be actively regulated in CD4 T cells. Multifunctional T-helper cell responses were maintained in DN T cells from uninfected and SIV infected mangabeys and persisted in mangabeys exhibiting SIV mediated CD4 loss. Interestingly, TCR stimulation of DN T cells from SIV infected mangabeys results in a decreased upregulation of IFNγ and increased IL5 and IL13 expression compared to uninfected mangabeys. Evaluation of proliferative capacity of DN T cells in vivo (BrDU labeling) indicated that these cells maintain their ability to proliferate despite SIV infection, and express the homeostatic cytokine receptors CD25 (IL2 receptor) and CD127 (IL7 receptor). This study identifies the potential for a CD4-negative T cell subset that is refractory to SIV infection to perform T-helper functions in mangabeys and suggests that immune therapeutics designed to increase DN T cell function during HIV infection may have beneficial effects for the host immune system. PMID:23825945

  15. Bell miner provisioning calls are more similar among relatives and are used by helpers at the nest to bias their effort towards kin

    PubMed Central

    McDonald, Paul G.; Wright, Jonathan

    2011-01-01

    Kin selection predicts that helpers in cooperative systems should preferentially aid relatives to maximize fitness. In family-based groups, this can be accomplished simply by assisting all group members. In more complex societies, where large numbers of kin and non-kin regularly interact, more sophisticated kin-recognition mechanisms are needed. Bell miners (Manorina melanophrys) are just such a system where individuals regularly interact with both kin and non-kin within large colonies. Despite this complexity, individual helpers of both sexes facultatively work harder when provisioning the young of closer genetic relatedness. We investigated the mechanism by which such adaptive discrimination occurs by assessing genetic kinship influences on the structure of more than 1900 provisioning vocalizations of 185 miners. These ‘mew’ calls showed a significant, positive linear increase in call similarity with increasing genetic relatedness, most especially in comparisons between male helpers and the breeding male. Furthermore, individual helping effort was more heavily influenced by call similarity to breeding males than to genetic relatedness, as predicted if call similarity is indeed the rule-of-thumb used to discriminate kin in this system. Individual mew call structure appeared to be inflexible and innate, providing an effective mechanism by which helpers can assess their relatedness to any individual. This provides, to our knowledge, the first example of a mechanism for fine-scale kin discrimination in a complex avian society. PMID:21450738

  16. Improved silencing suppression and enhanced heterologous protein expression are achieved using an engineered viral helper component proteinase.

    PubMed

    Haikonen, T; Rajamäki, M-L; Valkonen, J P T

    2013-11-01

    RNA silencing limits transient expression of heterologous proteins in plants. Co-expression of viral silencing suppressor proteins can increase and prolong protein expression, but highly efficient silencing suppressors may stress plant tissue and be detrimental to protein yields. Little is known whether silencing suppression could be improved without harm to plant tissues. This study reports development of enhanced silencing suppressors by engineering the helper component proteinase (HCpro) of Potato virus A (PVA). Mutations were introduced to a short region of HCpro (positions 330-335 in PVA HCpro), which is hypervariable among potyviruses. Three out of the four HCpro mutants suppressed RNA silencing more efficiently and sustained expression of co-expressed jellyfish green fluorescent protein for a longer time than wild-type HCpro in agroinfiltrated leaves of Nicotiana benthamiana. Leaf tissues remained healthy-looking without any visible signs of stress. PMID:23933077

  17. Anti-tumour necrosis factor treatment increases circulating T helper type 17 cells similarly in different types of inflammatory arthritis

    PubMed Central

    Hull, D N; Williams, R O; Pathan, E; Alzabin, S; Abraham, S; Taylor, P C

    2015-01-01

    We investigated changes in circulating T helper type 17 (Th17) cells following anti-tumour necrosis factor (TNF) in rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) patients. Peripheral blood mononuclear cells (PBMC) were isolated from 25 RA, 15 AS and eight PsA patients at baseline 4 and 12 weeks after treatment, and Th17 cell frequencies were analysed using interleukin (IL)-17 enzyme-linked immunospot (ELISPOT) and flow cytometry. A significant increase in IL-17-producing cells was observed by ELISPOT in RA and AS patients at 12 weeks. Flow cytometry confirmed significant increases in CD4+IL-17+ cells at 12 weeks in RA and AS and 4 weeks in PsA patients. Anti-TNF treatment increases circulating Th17 cells in three different diseases. PMID:25766640

  18. Immune polarization by hookworms: taking cues from T helper type 2, type 2 innate lymphoid cells and alternatively activated macrophages.

    PubMed

    Nair, Meera G; Herbert, De'Broski R

    2016-06-01

    Cellular and molecular investigation of parasitic helminth infections has greatly accelerated the understanding of type 2 immune responses. However, there remains considerable debate regarding the specific leucocytes that kill parasites and whether these mechanisms are distinct from those responsible for tissue repair. Herein, we chronicle discoveries over the past decade highlighting current paradigms in type 2 immunity with a particular emphasis upon how CD4(+) T helper type 2 cells, type 2 innate lymphoid cells and alternatively activated macrophages coordinately control helminth-induced parasitism. Primarily, this review will draw from studies of the murine nematode parasite Nippostrongylus brasiliensis, which bears important similarities to the human hookworms Ancylostoma duodenale and Necator americanus. Given that one or more hookworm species currently infect millions of individuals across the globe, we propose that vaccine and/or pharmaceutical-based cure strategies targeting these affected human populations should incorporate the conceptual advances outlined herein. PMID:26928141

  19. MicroRNA-22 Inhibits Histone Deacetylase 4 to Promote T Helper-17 Cell-Dependent Emphysema

    PubMed Central

    Lu, Wen; You, Ran; Yuan, Xiaoyi; Yang, Tianshu; Samuel, Errol L. G.; Marcano, Daniela C.; Sikkema, William K. A.; Tour, James M.; Rodriguez, Antony; Kheradmand, Farrah; Corry, David B.

    2015-01-01

    Smoking-related emphysema is a chronic inflammatory disease driven by T helper 17 (TH17) cells through molecular mechanisms that remain obscure. Here we have explored the role of microRNA-22 (miR-22) in emphysema. MiR-22 was upregulated in lung myeloid dendritic cells (mDCs) of smokers with emphysema and antigen-presenting cells (APCs) of mice exposed to smoke or nanoparticulate carbon black (nCB) through a mechanism involving NF-κB. MiR-22-deficient mice, but not wild-type, showed attenuated TH17 responses and failed to develop emphysema after exposure to either smoke or nCB. We further show that miR-22 controls APC activation and TH17 responses through activation of AP-1 transcription factor complexes and histone deacetylase (HDAC) 4. Thus, miR-22 is a critical regulator of both emphysema and TH17 responses. PMID:26437241

  20. Maternal IgG and IgA Antibodies Dampen Mucosal T Helper Cell Responses in Early Life.

    PubMed

    Koch, Meghan A; Reiner, Gabrielle L; Lugo, Kyler A; Kreuk, Lieselotte S M; Stanbery, Alison G; Ansaldo, Eduard; Seher, Thaddeus D; Ludington, William B; Barton, Gregory M

    2016-05-01

    To maintain a symbiotic relationship between the host and its resident intestinal microbiota, appropriate mucosal T cell responses to commensal antigens must be established. Mice acquire both IgG and IgA maternally; the former has primarily been implicated in passive immunity to pathogens while the latter mediates host-commensal mutualism. Here, we report the surprising observation that mice generate T cell-independent and largely Toll-like receptor (TLR)-dependent IgG2b and IgG3 antibody responses against their gut microbiota. We demonstrate that maternal acquisition of these antibodies dampens mucosal T follicular helper responses and subsequent germinal center B cell responses following birth. This work reveals a feedback loop whereby T cell-independent, TLR-dependent antibodies limit mucosal adaptive immune responses to newly acquired commensal antigens and uncovers a broader function for maternal IgG. PMID:27153495

  1. Development of a helper cell-dependent form of peste des petits ruminants virus: a system for making biosafe antigen.

    PubMed

    Baron, Jana; Baron, Michael D

    2015-01-01

    Peste des petits ruminants (PPR) is a viral disease of sheep and goats that is spreading through many countries in the developing world. Work on the virus is often restricted to studies of attenuated vaccine strains or to work in laboratories that have high containment facilities. We have created a helper cell dependent form of PPR virus by removing the entire RNA polymerase gene and complementing it with polymerase made constitutively in a cell line. The resultant L-deleted virus grows efficiently in the L-expressing cell line but not in other cells. Virus made with this system is indistinguishable from normal virus when used in diagnostic assays, and can be grown in normal facilities without the need for high level biocontainment. The L-deleted virus will thus make a positive contribution to the control and study of this important disease. PMID:26396073

  2. Development of a helper cell-dependent form of peste des petits ruminants virus: a system for making biosafe antigen.

    PubMed

    Baron, Jana; Baron, Michael D

    2015-09-23

    Peste des petits ruminants (PPR) is a viral disease of sheep and goats that is spreading through many countries in the developing world. Work on the virus is often restricted to studies of attenuated vaccine strains or to work in laboratories that have high containment facilities. We have created a helper cell dependent form of PPR virus by removing the entire RNA polymerase gene and complementing it with polymerase made constitutively in a cell line. The resultant L-deleted virus grows efficiently in the L-expressing cell line but not in other cells. Virus made with this system is indistinguishable from normal virus when used in diagnostic assays, and can be grown in normal facilities without the need for high level biocontainment. The L-deleted virus will thus make a positive contribution to the control and study of this important disease.

  3. Normalization of immunoregulatory T-helper T-suppressor sublineages and cell-mediated immunity by isoprinosine in vitro in the early stages of AIDS.

    PubMed

    Tsang, P; Bekesi, J G

    1987-01-01

    Applying flow cytometric analysis and a panel of monoclonal antibodies that define functional subsets and stages of lymphocyte differentiation, we found both inducer and suppressor regulating subsets of helper T cells to be depressed with concurrent increase in the functionally active effector suppressor T cells in prodromal homosexuals and patients with AIDS. Concomitantly a broad spectrum of aberrations in all stages of B cell developments were observed. Failure of isolated peripheral blood lymphocytes from these subjects to respond to formalin-fixed Staphylococcus aureus cowan 1 (SAC) indicated intrinsic defects in their resting B cells, while impairment in pokeweed mitogen (PWM)-induced blastogenesis coupled with increased levels of Ig secretion signified regulatory defects in their mature B cells, which may be related to helper-suppressor dysfunctions. Based on these findings, a multifactorial immunodysfunction in AIDS was proposed. The antiviral biological modulator drug isoprinosine was shown to enhance PWM-induced, T-cell dependent, B-cell blastogenesis and normalize the spontaneous secretion of Ig while showing no modulative effects on SAC-induced (resting B-cell) transformations. It also modified, in a selective fashion, the phenotypic coexpression of both HLA-DR and Leu8 antigen on helper and suppressor T cells. Among prodromal subjects at risk to develop AIDS, isoprinosine augmented the expression of both helper T-cell subsets while reducing the number of suppressor effector cells and activated suppressor cells. These interferences with the helper-suppressor regulatory loop may explain the therapeutic efficacy of this drug in the early stages of AIDS. PMID:2446761

  4. Role of receptor-binding activity of the viral hemagglutinin molecule in the presentation of influenza virus antigens to helper T cells.

    PubMed Central

    Eisenlohr, L C; Gerhard, W; Hackett, C J

    1987-01-01

    The concentration of antigen required to stimulate influenza virus-specific helper T cells was observed to be dependent upon the antigenic form bearing the relevant determinant: intact, nonreplicative virus was needed only in picomolar amounts, while denatured proteins, protein fragments, or synthetic peptides were required in micromolar concentrations for a threshold level of stimulation. Antigenic efficiency of intact virus was found to result from the attachment of virus to sialic acid residues on the surface of the antigen-presenting cell since spikeless viral particles lacking the hemagglutinin molecule were much less efficient antigens for helper T cells and continuous presence of hemagglutination-inhibiting antihemagglutinin antibodies reduced efficiency of stimulation by intact virus approximately 100-fold for both hemagglutinin and internal virion proteins. Influenza virus associated rapidly with antigen-presenting cells; less than 10 min at 20 degrees C was sufficient to introduce virus for a maximal level of T-cell stimulation. This rapid attachment was blocked by antibodies to the hemagglutinin or by pretreatment of the antigen-presenting cells with neuraminidase to remove the cellular virus receptor. Following viral adsorption by antigen-presenting cells, a lag period of 30 min at 37 degrees C was required for the expression of helper T-cell determinants. One early event identified was the movement of the virus to a neuraminidase-insensitive compartment, which can occur at 10 degrees C, but which was not equivalent to expression of helper T-cell determinants. Preincubation of cells with virus at 10 degrees C for 4 h reduced the lag period of helper T-cell determinant expression to 15 min when these cells were shifted to 37 degrees C, suggesting that transition of the virus to a neuraminidase-resistant state is a required step in presentation of T-cell antigenic determinants. PMID:2952806

  5. Interleukin 4 and T helper type 2 cells are required for development of experimental onchocercal keratitis (river blindness)

    PubMed Central

    1995-01-01

    Inflammation of the corneal stroma (stromal keratitis) is a serious complication of infection with the nematode parasite Onchocerca volvulus. Because stromal keratitis is believed to be immunologically mediated in humans, we used a murine model to examine the role of T cells and T helper cell cytokines in the immunopathogenesis of these eye lesions. BALB/c mice immunized subcutaneously and injected intrastromally with soluble O. volvulus antigens (OvAg) developed pronounced corneal opacification and neovascularization. The corneal stroma was edematous and contained numerous eosinophils and mononuclear cells. Stromal keratitis in immunized mice was determined to be T cell dependent based on the following observations: (a) T cell-deficient nude mice immunized and injected intrastromally with OvAg fail to develop corneal pathology; and (b) adoptive transfer of spleen cells from OvAg-immunized BALB/c mice to naive nude mice before intrastromal injection of OvAg results in development of keratitis. OvAg-stimulated lymph node and spleen cell cytokine production was dependent on CD4 cells and included interleukin (IL)-4 and IL-5, but not interferon gamma, indicating a predominant T helper type 2 cell-like response. Inflamed corneas from immunized BALB/c mice and from reconstituted nude mice had greatly elevated CD4 and IL-4 gene expression compared with interferon gamma. Mice in which the IL-4 gene was disrupted failed to develop corneal disease, demonstrating that IL-4 is essential in the immunopathogenesis of O. volvulus-mediated stromal keratitis. PMID:7561696

  6. Persistent Simian Immunodeficiency Virus Infection Drives Differentiation, Aberrant Accumulation, and Latent Infection of Germinal Center Follicular T Helper Cells

    PubMed Central

    Xu, Huanbin; Wang, Xiaolei; Malam, Naomi; Aye, Pyone P.; Alvarez, Xavier; Lackner, Andrew A.

    2015-01-01

    ABSTRACT CD4+ follicular T helper (Tfh) cells play a prominent role in humoral immune responses, but the mechanisms of their accumulation and infection in AIDS remain unclear. Here we found that germinal center (GC) Tfh cells, defined here as CXCR5+ PD-1HIGH CD4+ T cells, do not express the HIV coreceptor CCR5 yet serve as a latent reservoir in GCs. With disease progression, an expansion of GC Tfh cells is accompanied by increases in dysfunctional CD8+ T cells. In contrast, Tfh precursor (CXCR5− CD4+ T) cells in lymph nodes do express CCR5 and differentiate into GC Tfh cells following interleukin-6 (IL-6) and IL-21 stimulation, and viral DNA is detectable in fully differentiated GC Tfh cells ex vivo. This suggests that SIV-infected GC Tfh cells may be derived from Tfh precursor cell subsets that become infected in marginal zones and then migrate into GCs as fully mature GC Tfh cells that serve as persistent virus reservoirs. These findings suggest that viral persistence in lymph nodes drives compensatory differentiation, aberrant accumulation, and latent infection of GC Tfh cells, resulting in marked impairment of humoral immune responses. IMPORTANCE Generation of antibodies that can effectively eliminate viruses requires interactions of B cells with highly specialized T cells in GCs of lymphoid tissues called follicular T helper cells. Here we show that in simian immunodeficiency virus infection, these cells are initially infected in a precursor stage that leads to alterations in their homing, accumulation, and function that may be responsible for the inability of human immunodeficiency virus-infected patients to generate effective antibody responses. PMID:26608323

  7. Helper plasmid cloning in Streptococcus sanguis: cloning of a tetracycline resistance determinant from the Streptococcus mutans chromosome.

    PubMed

    Tobian, J A; Macrina, F L

    1982-10-01

    A model system for testing the helper plasmid cloning system of Gryczan et al. (Mol. Gen. Genet. 177:459-467, 1980) was devised for the Streptococcus sanguis (Challis) host-vector system. In this system, linearized pVA736 plasmid efficiently transformed an S. sanguis (Challis) host containing a homologous plasmid, pVA380-1, but did not transform a plasmidless host or a host containing a nonhomologous plasmid, pVA380. In addition, whereas monomeric circular pVA736 transformed a plasmidless host with two-hit kinetics, it transformed a pVA380-1-containing host with one-hit kinetics. This helper plasmid cloning system was used to isolate two HindIII fragments (5.0 megadaltons [Mdal] and 1.9 Mdal in size) from the chromosome of Streptococcus mutans V825 which conferred high-level tetracycline resistance. One tetracycline-resistant clone was examined and found to contain three plasmids which were sized and designated pVA868 (9.0 Mdal), pVA869 (9.5 Mdal), and pVA870 (9.8 Mdal). Results of Southern blot hybridization and restriction endonuclease digestion confirmed that all three chimeras were composed of two HindIII fragments of the S. mutans V825 chromosome, as well as a large portion, varying in size for each chimera, of the 2.8 Mdal cloning vector, pVA380-1. Incompatibility observed between pVA380-1 and each of the chimeras indicated that replication of the chimeras was governed by the pVA380-1 replicative origin. Southern blotting experiments revealed that the chimeras hybridized to Tn916, providing the first evidence that transposon-related genes of enteric streptococcal origin are disseminated among oral streptococci.

  8. The envelope gene and long terminal repeat sequences contribute to the pathogenic phenotype of helper-independent Friend viruses.

    PubMed Central

    Oliff, A; Signorelli, K; Collins, L

    1984-01-01

    Friend murine leukemia virus (F-MuLV) and Friend mink cell focus-inducing virus (Fr-MCF) are helper-independent murine retroviruses which induce a rapidly fatal erytholeukemia in NIH Swiss mice. Amphotropic clone 4070 (Ampho) is a murine retrovirus which does not cause leukemia in these animals. Mice inoculated with Ampho, an Fr-MCF/Ampho pseudotype, or F-MuLV developed leukemia in 0, 50, and 100% of animals, respectively. To identify the F-MuLV and Fr-MCF sequences responsible for leukemia, we constructed hybrid viral genomes between these viruses and Ampho, using subgenomic fragments of molecularly cloned viral DNA. Transfection of these hybrid viral DNAs into fibroblasts produces recombinant retroviruses. These new viruses are assayed in vivo for their ability to cause leukemia. Recombinant viruses constructed between the Ampho genome and the Fr-MCF envelope gene do not cause leukemia. Similarly, viruses constructed by using either the Fr-MCF long terminal repeat U3 region or the F-MuLV long terminal repeat U3 region and the remainder of the Ampho genome do not cause leukemia. However, if the Fr-MCF envelope gene plus the Fr-MCF U3 region are joined to Ampho, the resulting virus causes erythroleukemia in 14% of mice. Recombinant viruses made between the Fr-MCF envelope gene, the F-MuLV U3 region, and the remainder of the Ampho genome cause erythroleukemia in 38% of mice. This study demonstrates that both the envelope gene of Fr-MCF and the U3 regions of Fr-MCF and F-MuLV contain sequences which contribute to the leukemic phenotype of helper-independent Friend viruses. Images PMID:6088801

  9. In Vitro Effects of Propranolol on T Helper Type 1 Cytokine Profile in Human Leukemic T Cells

    PubMed Central

    Hajighasemi, Fatemeh; Mirshafiey, Abbas

    2016-01-01

    Introduction: Cytokines are a large group of proteins play a key role in inflammation. Down-regulation of pro-inflammatory cytokines has beneficial effect on heart function. Propranolol, as a non selective beta-adrenergic blocker, has been extensively used for treatment of many cardiovascular problems such as arrhythmias and heart malfunction. In addition anti-inflammatory effects of propranolol have been revealed. In this study the propranolol effect on T helper type 1 cytokine profile in human leukemic T cells has been assessed in vitro. Materials and methods: Human leukemic T cells (Molt-4 and Jurkat) were cultured in complete RPMI medium. The cells were then incubated with different concentrations of propranolol (0.03- 30 µM) in the presence or absence of PHA (10 µg/ml) for 48 hours. The supernatants of cell culture media were collected and used for cytokines assay. Results: Propranolol significantly decreased the T helper type 1 cytokine profile [Interleukin-2 (IL-2) and Interferon- γ (IFN-γ)] production in PHA stimulated Molt-4 and Jurkat cells, after 48 hour of incubation time, dose-dependently compared to untreated control cells. Conclusion: Our data showed a dose dependent inhibitory effect of propranolol on the IL-2 and IFN-γ production in human leukemic Molt-4 and Jurkat cells. The anti- inflammatory effect of propranolol reported by other investigators may be in part due to its suppressive effect on production of inflammatory cytokines such as IL-2 and IFN-γ. So, propranolol along with its chronic long-term usage in cardiovascular problems may have potential implication in treatment of inflammatory-based disorders. PMID:27252810

  10. Mechanisms of Low Dose Radiation-induced T helper Cell Function

    SciTech Connect

    Gridley, Daila S.

    2008-10-31

    Exposure to radiation above levels normally encountered on Earth can occur during wartime, accidents such as those at Three Mile Island and Chernobyl, and detonation of “dirty bombs” by terrorists. Relatively high levels of radiation exposure can also occur in certain occupations (low-level waste sites, nuclear power plants, nuclear medicine facilities, airline industry, and space agencies). Depression or dysfunction of the highly radiosensitive cells of the immune system can lead to serious consequences, including increased risk for infections, cancer, hypersensitivity reactions, poor wound healing, and other pathologies. The focus of this research was on the T helper (Th) subset of lymphocytes that secrete cytokines (proteins), and thus control many actions and interactions of other cell types that make up what is collectively known as the immune system. The Department of Energy (DOE) Low Dose Radiation Program is concerned with mechanisms altered by exposure to high energy photons (x- and gamma-rays), protons and electrons. This study compared, for the first time, the low-dose effects of two of these radiation forms, photons and protons, on the response of Th cells, as well as other cell types with which they communicate. The research provided insights regarding gene expression patterns and capacity to secrete potent immunostimulatory and immunosuppressive cytokines, some of which are implicated in pathophysiological processes. Furthermore, the photon versus proton comparison was important not only to healthy individuals who may be exposed, but also to patients undergoing radiotherapy, since many medical centers in the United States, as well as worldwide, are now building proton accelerators. The overall hypothesis of this study was that whole-body exposure to low-dose photons (gamma-rays) will alter CD4+ Th cell function. We further proposed that exposure to low-dose proton radiation will induce a different pattern of gene and functional changes compared to

  11. Lack of competition results in efficient packaging of heterologous murine retroviral RNAs and reticuloendotheliosis virus encapsidation-minus RNAs by the reticuloendotheliosis virus helper cell line.

    PubMed Central

    Embretson, J E; Temin, H M

    1987-01-01

    We constructed recombinant reticuloendotheliosis virus (Rev)-derived and murine leukemia virus-derived vectors to characterize the specificity of packaging retroviral RNAs in Rev proteins. Using this approach, we further localized the Rev encapsidation sequence (E) to a 144-nucleotide region and determined that there are sequences in both the 5' and 3' halves of this region which are necessary in cis for viral replication. We found that the Rev E, like the murine leukemia virus E (psi), is position independent (R. Mann and D. Baltimore, J. Virol. 54:401-407, 1986). Also, a 156-nucleotide region of the Rev intron enhanced replication in a cis-acting fashion in the presence, but not in the absence, of helper virus. Finally, we showed that packaging of E- and heterologous retroviral genomes occurred efficiently in the Rev helper cell in the absence of competing E-containing (E+) viral RNAs. Images PMID:3039161

  12. TGF-β and retinoic acid induce miR-10a, which targets Bcl-6 and constrains helper T cell plasticity

    PubMed Central

    Takahashi, Hayato; Kanno, Tomohiko; Nakayamada, Shingo; Hirahara, Kiyoshi; Sciumè, Giuseppe; Muljo, Stefan A.; Kuchen, Stefan; Casellas, Rafael; Wei, Lai; Kanno, Yuka; O'Shea, John J.

    2012-01-01

    Distinct CD4+ T cell subsets are critical for host defense and immunoregulation. While these subsets can behave as terminally differentiated lineages, elements of plasticity are increasingly recognized. MicroRNAs are one factor that controls stability and plasticity. Herein, we report that miR-10a was highly expressed in naturally-occurring regulatory T (Treg) cells and induced by retinoic acid and TGF-β in inducible Treg cells. By simultaneously targeting Bcl-6 and a co-repressor, Ncor2, miR-10a attenuated phenotypic conversion of inducible Treg cells to follicular helper T cells. miR-10a also limited TH17 differentiation and therefore represents a new factor that can fine tune plasticity and fate decision of helper T cells. PMID:22544395

  13. Transient expression of a GUS reporter gene from cauliflower mosaic virus replacement vectors in the presence and absence of helper virus.

    PubMed

    Viaplana, R; Turner, D S; Covey, S N

    2001-01-01

    Vectors based upon the genome of cauliflower mosaic virus (CaMV) have only a limited capacity for replicating foreign DNA in plants. A helper virus system has been developed to complement CaMV constructs capable of carrying a large foreign gene (glucuronidase; GUS). GUS replaced part or all of the non-essential CaMV gene II and the essential genes III, IV and V. This construct was co-inoculated mechanically with wild-type CaMV helper virus onto Brassica rapa leaves to promote GUS vector complementation. After 1 week, blue foci of GUS activity were observed in the centres of the local lesions. Leaves inoculated with the GUS construct in the absence of helper virus showed randomly distributed foci of GUS activity that were generally smaller than the lesion-associated GUS foci. Inoculation with a simple non-replicating CaMV 35S promoter-GUS construct also produced small GUS foci. Co-inoculation of helper virus with CaMV gene replacement vectors in which replication was prevented by moving the primer-binding site or by deletion of an essential splice acceptor produced only small, randomly distributed GUS activity foci, demonstrating that the lesion-associated foci were produced by gene expression from replicating constructs. These experiments show that CaMV genes III-V can be complemented by wild-type virus and replacement gene vectors can be used for transient gene expression studies with CaMV constructs that distinguish gene expression associated with a replicating vector from that associated with a non-replicating vector.

  14. Peptide-specific T helper cells identified by MHC class II tetramers differentiate into several subtypes upon immunization with CAF01 adjuvanted H56 tuberculosis vaccine formulation.

    PubMed

    Prota, Gennaro; Christensen, Dennis; Andersen, Peter; Medaglini, Donata; Ciabattini, Annalisa

    2015-11-27

    CD4(+) T-cell priming is an essential step in vaccination due to the key role of T helper cells in driving both effector and memory immune responses. Here we have characterized in C57BL/6 mice the T helper subtype differentiation among tetramer-specific CD4(+) T cells primed by subcutaneous immunization with the tuberculosis vaccine antigen H56 plus the adjuvant CAF01. Peptide-specific population identified by the MHC class II tetramers differentiated into several T helper subtypes upon antigen encounter, and the frequency of subpopulations differed according to their localization. Th1 (CXCR3(+)T-bet(+)), Tfh (CXCR5(+)PD-1(+)Bcl-6(+)) and RORγt(+) cells were induced in the lymph nodes draining the immunization site (dLN), while Th1 cells were the predominant subtype in the spleen. In addition, CD4(+) T cells co-expressing multiple T-cell lineage-specifying transcription factors were also detected. In the lungs, most of the tetramer-binding T cells were RORγt(+), while Tfh and Th1 cells were absent. After boosting, a higher frequency of tetramer-binding cells co-expressing the markers CD44 and CD127 was detected compared to primed cells, and cells showed a prevalent Th1 phenotype in both dLN and spleens, while Tfh cells were significantly reduced. In conclusion, these data demonstrate that parenteral immunization with H56 and CAF01 elicits a distribution of antigen-specific CD4(+) T cells in both lymphoid tissues and lungs, and gives rise to multiple T helper subtypes, that differ depending on localization and following reactivation.

  15. Reduced HIV-stimulated T-helper cell reactivity in cord blood with short-course antiretroviral treatment for prevention of maternal–infant transmission

    PubMed Central

    Kuhn, L; Meddows-Taylor, S; Gray, G; Trabattoni, D; Clerici, M; Shearer, G M; Tiemessen, C

    2001-01-01

    T-helper cell responses to HIV have been associated with protection against maternal-infant HIV transmission in the absence of antiretroviral treatment, but the effects of antiretroviral treatment, now widely used for prevention, on development of these cell-mediated responses is unknown. We tested whether development of T-helper cell responses to HIV and other antigens would be affected by exposure to short-course regimens of zidovudine-lamivudine (ZDV-3TC) given to prevent maternal-infant HIV transmission. Cord blood samples were collected from 41 infants of HIV-infected mothers enrolled in a clinical trial in which they were treated with regimens of ZDV-3TC and from 29 infants whose HIV-infected mothers were not treated with any antiretroviral drugs. T-helper cell reactivity to HIV envelope peptides and other antigens was measured in vitro using a sensitive culture supernatant titration assay based on IL-2-dependent proliferation. Infants in the clinical trial were followed to 18 months to determine their HIV infection status, and venous blood samples were re-tested at 4·5 and 9 months for T-cell reactivity to HIV. HIV-stimulated T-helper cell reactivity in cord blood was detected 10-fold less frequently among those exposed to antiretroviral prophylaxis (2·4%) than among those unexposed (24·1%) (P = 0·007). Reductions in HIV-stimulated responses in cord blood occurred despite detectable HIV RNA (mean 3·38 standard deviation 0·76 log10 copies per ml) at delivery among treated women and occurred independent of treatment duration. Our results suggest that short-course antiretroviral treatment given to prevent maternal-infant HIV transmission may attenuate HIV-stimulated T-cell memory responses in the neonate. PMID:11298132

  16. Sensitive and selective amplification of methylated DNA sequences using helper-dependent chain reaction in combination with a methylation-dependent restriction enzymes.

    PubMed

    Rand, Keith N; Young, Graeme P; Ho, Thu; Molloy, Peter L

    2013-01-01

    We have developed a novel technique for specific amplification of rare methylated DNA fragments in a high background of unmethylated sequences that avoids the need of bisulphite conversion. The methylation-dependent restriction enzyme GlaI is used to selectively cut methylated DNA. Then targeted fragments are tagged using specially designed 'helper' oligonucleotides that are also used to maintain selection in subsequent amplification cycles in a process called 'helper-dependent chain reaction'. The process uses disabled primers called 'drivers' that can only prime on each cycle if the helpers recognize specific sequences within the target amplicon. In this way, selection for the sequence of interest is maintained throughout the amplification, preventing amplification of unwanted sequences. Here we show how the method can be applied to methylated Septin 9, a promising biomarker for early diagnosis of colorectal cancer. The GlaI digestion and subsequent amplification can all be done in a single tube. A detection sensitivity of 0.1% methylated DNA in a background of unmethylated DNA was achieved, which was similar to the well-established Heavy Methyl method that requires bisulphite-treated DNA.

  17. The minimal sequence essential for replication and movement of Cotton leaf curl Multan betasatellite DNA by a helper virus in plant cells.

    PubMed

    Eini, Omid; Behjatnia, S A Akbar

    2016-10-01

    Betasatellites are single-stranded circular DNAs associated with a number of monopartite begomoviruses. Betasatellites rely on the helper begomoviruses for replication and movement in plant tissues and plant-to-plant transmission by vectors. Their genomes are approximately half the size of the helper viruses and consist of three main regions including the βC1 gene, an adenine-rich (A-rich) region, and the satellite conserved region (SCR). In this study, we investigated the minimal sequences required for Cotton leaf curl Multan betasatellite (CLCuMB) replication and movement. Mutational analysis of CLCuMB DNA genome indicated that βC1 gene and A-rich region were not required for trans-replication and movement of CLCuMB in host plants by a helper virus. Deletion of βC1 gene and a fragment (135 nt in length) upstream of this gene impaired CLCuMB replication. However, CLCuMB mutant with deletion of βC1 gene and a further 163 nucleotides replicated at a lower level as compared to the wild-type betasatellite. This suggests that there are essential elements in the fragment upstream of βC1 gene, which are required for the replication of CLCuMB rather than the size limitation of CLCuMB DNA. PMID:27193570

  18. The minimal sequence essential for replication and movement of Cotton leaf curl Multan betasatellite DNA by a helper virus in plant cells.

    PubMed

    Eini, Omid; Behjatnia, S A Akbar

    2016-10-01

    Betasatellites are single-stranded circular DNAs associated with a number of monopartite begomoviruses. Betasatellites rely on the helper begomoviruses for replication and movement in plant tissues and plant-to-plant transmission by vectors. Their genomes are approximately half the size of the helper viruses and consist of three main regions including the βC1 gene, an adenine-rich (A-rich) region, and the satellite conserved region (SCR). In this study, we investigated the minimal sequences required for Cotton leaf curl Multan betasatellite (CLCuMB) replication and movement. Mutational analysis of CLCuMB DNA genome indicated that βC1 gene and A-rich region were not required for trans-replication and movement of CLCuMB in host plants by a helper virus. Deletion of βC1 gene and a fragment (135 nt in length) upstream of this gene impaired CLCuMB replication. However, CLCuMB mutant with deletion of βC1 gene and a further 163 nucleotides replicated at a lower level as compared to the wild-type betasatellite. This suggests that there are essential elements in the fragment upstream of βC1 gene, which are required for the replication of CLCuMB rather than the size limitation of CLCuMB DNA.

  19. Combination peptide immunotherapy suppresses antibody and helper T-cell responses to the RhD protein in HLA-transgenic mice

    PubMed Central

    Hall, Lindsay S.; Hall, Andrew M.; Pickford, Wendy; Vickers, Mark A.; Urbaniak, Stanislaw J.; Barker, Robert N.

    2014-01-01

    The offspring from pregnancies of women who have developed anti-D blood group antibodies are at risk of hemolytic disease of the newborn. We have previously mapped four peptides containing immunodominant T-helper cell epitopes from the RhD protein and the purpose of the work was to develop these into a product for suppression of established anti-D responses. A panel of each of the four immunodominant RhD peptides was synthesized with modifications to improve manufacturability and solubility, and screened for retention of recognition by human T-helper cells. A selected version of each sequence was combined in a mixture (RhDPmix), which was tested for suppressive ability in a humanized murine model of established immune responses to RhD protein. After HLA-DR15 transgenic mice had been immunized with RhD protein, a single dose of RhDPmix, given either intranasally (P=0.008, Mann-Whitney rank sum test) or subcutaneously (P=0.043), rapidly and significantly suppressed the ongoing antibody response. This was accompanied by reduced T-helper cell responsiveness, although this change was less marked for subcutaneous RhDPmix delivery, and by the recruitment of cells with a regulatory T-cell phenotype. The results support human trials of RhDPmix peptide immunotherapy in women with established antibody responses to the RhD blood group. PMID:24441145

  20. Specific inhibition of lymphokine biosynthesis and autocrine growth using antisense oligonucleotides in Th1 and Th2 helper T cell clones

    PubMed Central

    1988-01-01

    T helper cells have recently been divided into two subsets. The Th1 subset secretes and responds to IL-2 in an autocrine manner. The Th2 subset upon mitogen or antigen stimulation releases IL-4. Here we describe a novel technology that allowed us to confirm this distinction. We have used synthetic oligonucleotides complementary to the 5' end of mouse IL-2 and IL-4 to specifically block the biosynthesis of IL-2 or IL-4 in two murine helper T cell clones from the Th1 or Th2 subset. We show that the antisense IL-2 oligonucleotide inhibited the proliferation of the Th1 clone and had no effect on the Th2 clone. In parallel experiments, the antisense IL-4 oligonucleotide blocked the proliferation of the Th2 clone and not the proliferation of the Th1 clone. The inhibition was significantly reversed in both cases by the addition of the relevant lymphokine (IL-2 in the case of the Th1 clone, IL-4 in the case of the Th2 clone). Northern analysis, using cDNA probes specific for the two lymphokines, showed a decrease in the steady-state level of the relevant lymphokine mRNA, suggesting the specific degradation of the mRNA by an RNase H-like enzymatic activity. This strategy, which allows the specific blockade of the biosynthesis of a lymphokine, could be useful for future studies on the role of each T helper subset in physiological immune responses. PMID:2974066

  1. Interleukin 1 enhances vaccine-induced antifungal T-helper 17 cells and resistance against Blastomyces dermatitidis infection.

    PubMed

    Wüthrich, Marcel; LeBert, Vanessa; Galles, Kevin; Hu-Li, Jane; Ben-Sasson, Shlomo Z; Paul, William E; Klein, Bruce S

    2013-10-01

    Vaccine-induced T-helper 17 (Th17) cells are necessary and sufficient to protect against fungal infection. Although live fungal vaccines are efficient in driving protective Th17 responses and immunity, attenuated fungi may not be safe for human use. Heat-inactivated formulations and subunit vaccines are safer but less potent and require adjuvant to increase their efficacy. Here, we show that interleukin 1 (IL-1) enhances the capacity of weak vaccines to induce protection against lethal Blastomyces dermatitidis infection in mice and is far more effective than lipopolysaccharide. While IL-1 enhanced expansion and differentiation of fungus-specific T cells by direct action on those cells, cooperation with non-T cells expressing IL-1R1 was necessary to maximize protection. Mechanistically, IL-17 receptor signaling was required for the enhanced protection induced by IL-1. Thus, IL-1 enhances the efficacy of safe but inefficient vaccines against systemic fungal infection in part by increasing the expansion of CD4(+) T cells, allowing their entry into the lungs, and inducing their differentiation to protective Th17 cells.

  2. Evaluation of transcription factor that regulates T helper 17 and regulatory T cells function in periodontal health and disease

    PubMed Central

    Karthikeyan, B.; Talwar; Arun, K. V.; Kalaivani, S.

    2015-01-01

    Background: The differentiation of naοve T helper (Th) cells towards Th17 and regulatory T cells (Treg) is regulated by the transcription factors retinoic acid related orphan receptor gamma transcription (RORYt) and Forkhead box p3 (Foxp3), respectively. An imbalance in the activity of these transcription factors could result in the dysregulation of Th17/Treg response. Materials and Methods: Total RNA was isolated from gingival tissue obtained from 10 patients, each from periodontally healthy and diseased groups. The gene expression of RORYt and Foxp3 was measured by real-time reverse transcription polymerization chain reaction using total RNA isolates from gingival tissues group when compared to the healthy group, while Foxp3 demonstrated a 6.68 ± 0.03 fold decrease of expression in diseased group when compared to healthy group. Conclusion: Our results indicate a functional imbalance in the Th17/Treg response in periodontal disease group when compared to the periodontally healthy group. PMID:26538941

  3. High frequency of IL-4 producing helper T lymphocytes associated with a reduced incidence of heart allograft rejection.

    PubMed

    Van Hoffen, E; Polen, E; Robertus-Teunissen, M; De Jonge, N; Lahpor, J R; Gmelig-Meyling, F H; De Weger, R A

    2000-01-01

    The reduction in the frequency of rejection episodes several months after heart transplantation (HTX) correlates with the development of donor-specific nonresponsiveness. This is reflected in a reduced frequency of donor-specific cytotoxic T cells (CTL) in the peripheral blood. We investigated whether the reduced CTL frequency and the incidence of rejection episodes coincided with a change in the frequency of either IL-2- or IL-4-producing helper T lymphocytes (HTL). We measured the frequency of HTL before and at several time points after HTX in the blood of ten recipients, using limiting dilution analysis for IL-2 and IL-4. In most patients, HTL frequencies dropped immediately after transplantation, but returned to pre-HTX values later after transplantation. No consistent decrease or increase in frequencies was observed long after HTX. In contrast to IL-2, the HTL frequencies for IL-4 before transplantation were significantly higher in patients without post-HTX rejection episodes requiring treatment than in patients with such episodes. This phenomenon was observed for the in vitro responses towards both donor and third-party cells. In conclusion, relatively high frequencies of IL-4-producing T cells may have a beneficial effect on the outcome of human heart transplantation, because they are associated with a reduced incidence of rejection episodes after transplantation. PMID:11111999

  4. High Intestinal and Systemic Levels of Interleukin-23/T-Helper 17 Pathway in Chinese Patients with Inflammatory Bowel Disease

    PubMed Central

    Zhou, Rui; Huang, Sha; Zhou, Feng; Xu, Shufang; Yi, Fengming; Xia, Bing

    2013-01-01

    Interleukin-23/T-helper 17 (IL-23/Th17) pathway plays a key role in the pathogenesis of inflammatory bowel disease (IBD), but little is known about its expression in Chinese population. In this study, we investigated the mRNA and protein levels of IL-12p40, tumor necrosis factor-like cytokine 1A (TL1A), Janus kinase 2 (JAK2), and IL-23R both locally and systemically in Chinese IBD patients. Our results indicated that the mRNA levels of IL-12p40 and TL1A were increased in ulcerative colitis (UC) patients. Furthermore, serum IL-12p40 and TL1A levels were higher in active UC patients, especially in patients with disease course less than 1.25 years or initial onset. No correlation was found between the genotype and serum levels of IL-12p40 or TL1A in UC patients. Additionally, the mRNA and protein expression of JAK2 and IL-23R were increased in UC and Crohn's disease (CD) patients. Taken together, our results provided evidence that IL-23/Th17 pathway genes may represent important biomarkers of active stage of IBD and serve as novel therapeutic targets for IBD in Chinese population. PMID:24382939

  5. CD8+ Cells Regulate the T helper-17 Response in an Experimental Murine Model of Sjögren Syndrome

    PubMed Central

    Zhang, X.; Schaumburg, C.S.; Coursey, T.G.; Siemasko, K.F.; Volpe, E. A.; Gandhi, N.B.; Li, D.-Q.; Niederkorn, J.Y.; Stern, M.E.; Pflugfelder, S.C.; de Paiva, C.S.

    2013-01-01

    This study investigated the regulatory function of CD8+ cells in T helper (Th) 17 cell-mediated corneal epithelial barrier disruption that develops in a murine desiccating stress (DS) model that resembles Sjögren syndrome. CD8+ cell depletion promoted generation of IL-17A producing CD4+ T cells via activation of dendritic cells in both the ocular surface and draining cervical lymph nodes in C57BL/6 mice subjected to DS. T cell-deficient nude recipient mice receiving adoptively transferred CD4+ T cells from CD8+ cell-depleted donors exposed to DS displayed increased CD4+ T cell infiltration and elevated IL-17A and CCL20 levels in the ocular surface, which was associated with greater corneal barrier disruption. Enhanced DS-specific corneal barrier disruption in CD8-depleted donor mice correlated with a Th17-mediated expression of matrixmetalloproteinases (MMP-3 and MMP-9) in the recipient corneal epithelium. Co-transfer of CD8+ CD103+ Tregs did not affect the ability of DS-specific pathogenic CD4+ T cells to infiltrate and cause ocular surface disease in the nude recipients, showing that CD8+ cells regulate the afferent arm of DS-induced immune response. In summary, CD8+ regulatory cells suppress generation of a pathogenic Th17 response that plays a pivotal role in DS-induced disruption of corneal barrier function. PMID:24022789

  6. Transgene Expression up to 7 Years in Nonhuman Primates Following Hepatic Transduction with Helper-Dependent Adenoviral Vectors

    PubMed Central

    Brunetti-Pierri, Nicola; Ng, Thomas; Iannitti, David; Cioffi, William; Stapleton, Gary; Law, Mark; Breinholt, John; Palmer, Donna; Grove, Nathan; Rice, Karen; Bauer, Cassondra; Finegold, Milton; Beaudet, Arthur; Mullins, Charles

    2013-01-01

    Abstract Helper-dependent adenoviral vectors (HDAd) have been shown to mediate a considerably longer duration of transgene expression than first-generation adenoviral vectors. We have previously shown that transgene expression from HDAd-transduced hepatocytes can persist at high levels for up to 2.6 years in nonhuman primates following a single-vector administration. Because duration of transgene expression and long-term toxicity are critical for risk:benefit assessment, we have continued to monitor these animals. We report here that transgene expression has persisted for the entire observation period of up to 7 years for all animals without long-term adverse effects. However, in all cases, transgene expression level slowly declined over time to less than 10% of peak values by the end of the observation period but remained 2.3–111-fold above baseline values. These results will provide important information for a more informed risk:benefit assessment before clinical application of HDAd. PMID:23902403

  7. OX40 controls effector CD4+ T-cell expansion, not follicular T helper cell generation in acute Listeria infection

    PubMed Central

    Marriott, Clare L; Mackley, Emma C; Ferreira, Cristina; Veldhoen, Marc; Yagita, Hideo; Withers, David R

    2014-01-01

    To investigate the importance of OX40 signals for physiological CD4+ T-cell responses, an endogenous antigen-specific population of CD4+ T cells that recognise the 2W1S peptide was assessed and temporal control of OX40 signals was achieved using blocking or agonistic antibodies (Abs) in vivo. Following infection with Listeria monocytogenes expressing 2W1S peptide, OX40 was briefly expressed by the responding 2W1S-specific CD4+ T cells, but only on a subset that co-expressed effector cell markers. This population was specifically expanded by Ab-ligation of OX40 during priming, which also caused skewing of the memory response towards effector memory cells. Strikingly, this greatly enhanced effector response was accompanied by the loss of T follicular helper (TFH) cells and germinal centres. Mice deficient in OX40 and CD30 showed normal generation of TFH cells but impaired numbers of 2W1S-specific effector cells. OX40 was not expressed by 2W1S-specific memory cells, although it was rapidly up-regulated upon challenge whereupon Ab-ligation of OX40 specifically affected the effector subset. In summary, these data indicate that for CD4+ T cells, OX40 signals are important for generation of effector T cells rather than TFH cells in this response to acute bacterial infection. PMID:24771127

  8. Lymphoid enhancer factor interacts with GATA-3 and controls its function in T helper type 2 cells

    PubMed Central

    Hossain, Mohammad B; Hosokawa, Hiroyuki; Hasegawa, Akihiro; Watarai, Hiroshi; Taniguchi, Masaru; Yamashita, Masakatsu; Nakayama, Toshinori

    2008-01-01

    GATA-3 is the master transcription factor for T helper 2 (Th2) cell differentiation and is critical for the expression of Th2 cytokines. Little is known, however, about the nature of the functional molecular complexes of GATA-3. We identified a high-mobility group (HMG)-box type transcription factor, lymphoid enhancer factor 1 (LEF-1), in the GATA-3 complex present in Th2 cells using a Flag-calmodulin-binding peptide (CBP)-tag based proteomics method. The interaction between GATA-3 and LEF-1 was confirmed by co-immunoprecipitation experiments using LEF-1-introduced T-cell lineage TG40 cells. The HMG-box domain of LEF-1 and two zinc finger domains of GATA-3 were found to be important for the physical association. The introduction of LEF-1 into developing Th2 cells resulted in the suppression of Th2 cytokine production. The suppression was significantly lower in the cells into which a HMG-box-deleted LEF-1 mutant was introduced. Moreover, LEF-1 inhibited the binding activity of GATA-3 to the interleukin (IL)-5 promoter. These results suggest that LEF-1 is involved in the GATA-3 complex, while also regulating the GATA-3 function, such as the induction of Th2 cytokine expression via the inhibition of the DNA-binding activity of GATA-3. PMID:18445004

  9. Neo-islet formation in liver of diabetic mice by helper-dependent adenoviral vector-mediated gene transfer.

    PubMed

    Li, Rongying; Oka, Kazuhiro; Yechoor, Vijay

    2012-01-01

    Type 1 diabetes is caused by T cell-mediated autoimmune destruction of insulin-producing cells in the pancreas. Until now insulin replacement is still the major therapy, because islet transplantation has been limited by donor availability and by the need for long-term immunosuppression. Induced islet neogenesis by gene transfer of Neuogenin3 (Ngn3), the islet lineage-defining specific transcription factor and Betacellulin (Btc), an islet growth factor has the potential to cure type 1 diabetes. Adenoviral vectors (Ads) are highly efficient gene transfer vector; however, early generation Ads have several disadvantages for in vivo use. Helper-dependent Ads (HDAds) are the most advanced Ads that were developed to improve the safety profile of early generation of Ads and to prolong transgene expression(1). They lack chronic toxicity because they lack viral coding sequences(2-5) and retain only Ad cis elements necessary for vector replication and packaging. This allows cloning of up to 36 kb genes. In this protocol, we describe the method to generate HDAd-Ngn3 and HDAd-Btc and to deliver these vectors into STZ-induced diabetic mice. Our results show that co-injection of HDAd-Ngn3 and HDAd-Btc induces 'neo islets' in the liver and reverses hyperglycemia in diabetic mice. PMID:23093064

  10. T helper type 2-polarized invariant natural killer T cells reduce disease severity in acute intra-abdominal sepsis

    PubMed Central

    Anantha, R V; Mazzuca, D M; Xu, S X; Porcelli, S A; Fraser, D D; Martin, C M; Welch, I; Mele, T; Haeryfar, S M M; McCormick, J K

    2014-01-01

    Sepsis is characterized by a severe systemic inflammatory response to infection that is associated with high morbidity and mortality despite optimal care. Invariant natural killer T (iNK T) cells are potent regulatory lymphocytes that can produce pro- and/or anti-inflammatory cytokines, thus shaping the course and nature of immune responses; however, little is known about their role in sepsis. We demonstrate here that patients with sepsis/severe sepsis have significantly elevated proportions of iNK T cells in their peripheral blood (as a percentage of their circulating T cells) compared to non-septic patients. We therefore investigated the role of iNK T cells in a mouse model of intra-abdominal sepsis (IAS). Our data show that iNK T cells are pathogenic in IAS, and that T helper type 2 (Th2) polarization of iNK T cells using the synthetic glycolipid OCH significantly reduces mortality from IAS. This reduction in mortality is associated with the systemic elevation of the anti-inflammatory cytokine interleukin (IL)-13 and reduction of several proinflammatory cytokines within the spleen, notably interleukin (IL)-17. Finally, we show that treatment of sepsis with OCH in mice is accompanied by significantly reduced apoptosis of splenic T and B lymphocytes and macrophages, but not natural killer cells. We propose that modulation of iNK T cell responses towards a Th2 phenotype may be an effective therapeutic strategy in early sepsis. PMID:24965554

  11. Lack of Impact of High Dietary Vitamin A on T Helper 2-Dependent Contact Hypersensitivity to Fluorescein Isothiocyanate in Mice.

    PubMed

    Kobayashi, Chie; Kurohane, Kohta; Imai, Yasuyuki

    2015-01-01

    Overuse of vitamin A as a dietary supplement is a concern in industrialized countries. High-level dietary vitamin A is thought to shift immunity to a T helper 2 (Th2)-dominant one, resulting in the promotion of allergies. We have been studying a fluorescein isothiocyanate (FITC)-induced contact hypersensitivity (CHS) mouse model that involves Th2-type immunity. We fed a diet with a high retinyl palmitate content (250 international units (IU)/g diet) or a control diet (4 IU/g diet) to BALB/c mice for three weeks. No augmentation of FITC-induced CHS was found in mice fed the diet with a high vitamin A content, although accumulation of the vitamin was confirmed in the livers of these animals. The results indicated that relatively short-term feeding of the high-level vitamin A diet did not influence the Th2-driven response at a stage with significant retinol accumulation in the liver. The results were in contrast to the high-dose pyridoxine diets that produced a reduced response in FITC-induced CHS. PMID:26299258

  12. CD95-Mediated Calcium Signaling Promotes T Helper 17 Trafficking to Inflamed Organs in Lupus-Prone Mice.

    PubMed

    Poissonnier, Amanda; Sanséau, Doriane; Le Gallo, Matthieu; Malleter, Marine; Levoin, Nicolas; Viel, Roselyne; Morere, Lucie; Penna, Aubin; Blanco, Patrick; Dupuy, Alain; Poizeau, Florence; Fautrel, Alain; Seneschal, Julien; Jouan, Florence; Ritz, Jerome; Forcade, Edouard; Rioux, Nathalie; Contin-Bordes, Cécile; Ducret, Thomas; Vacher, Anne-Marie; Barrow, Paul A; Flynn, Robin J; Vacher, Pierre; Legembre, Patrick

    2016-07-19

    CD95 ligand (CD95L) is expressed by immune cells and triggers apoptotic death. Metalloprotease-cleaved CD95L (cl-CD95L) is released into the bloodstream but does not trigger apoptotic signaling. Hence, the pathophysiological role of cl-CD95L remains unclear. We observed that skin-derived endothelial cells from systemic lupus erythematosus (SLE) patients expressed CD95L and that after cleavage, cl-CD95L promoted T helper 17 (Th17) lymphocyte transmigration across the endothelial barrier at the expense of T regulatory cells. T cell migration relied on a direct interaction between the CD95 domain called calcium-inducing domain (CID) and the Src homology 3 domain of phospholipase Cγ1. Th17 cells stimulated with cl-CD95L produced sphingosine-1-phosphate (S1P), which promoted endothelial transmigration by activating the S1P receptor 3. We generated a cell-penetrating CID peptide that prevented Th17 cell transmigration and alleviated clinical symptoms in lupus mice. Therefore, neutralizing the CD95 non-apoptotic signaling pathway could be an attractive therapeutic approach for SLE treatment. PMID:27438772

  13. Loss of T Follicular Helper Cells In the Peripheral Blood Of Patients With Chronic Graft vs. Host Disease

    PubMed Central

    Knorr, David A.; Wang, Hongbo; Aurora, Mukta; MacMillan, Margaret L.; Holton, Shernan G.; Bergerson, Rachel; Cao, Qing; Weisdorf, Daniel J.; Cooley, Sarah; Brunstein, Claudio; Miller, Jeffery S.; Wagner, John E.; Blazar, Bruce R.; Verneris, Michael R.

    2016-01-01

    B cell anti-host antibody production plays a central role in chronic graft-vs-host disease (cGVHD). T follicular helper (TFH) cells drive B cell responses and are implicated in this process. Given differences in cGVHD incidence between umbilical cord blood (UCB) and adult donor transplant recipients, we evaluated TFH cell reconstitution kinetics to define graft source differences and their potential pathogenic role in cGVHD. Although we observed significantly fewer TFH cells in the blood of UCB recipients (vs. matched related donors (MRD)) early after transplantation, by 1 year the numbers of TFH cells were similar. Additionally, at both early (day 60) and late (1 year) time points, TFH cell phenotype was predominantly central memory cells in both cohorts. TFH cells were functional and able to produce multiple cytokines (INF-γ, TNF-α, IL-2, IL-17 and IL-21) following stimulation. In contrast to mouse models where an enhanced frequency of splenic TFH cells contributes to cGVHD, patients with cGVHD showed significantly depleted circulating TFH cells following both UCB and MRD transplantation. Low numbers of TFH cells early after UCB transplantation could directly contribute to less cGVHD in this cohort. Additionally, systemic therapy (including steroids and calcineurin inhibitors) may contribute to decreases in TFH cells in patients with cGVHD. These data provide further evidence supporting the importance of TFH cells in cGVHD pathogenesis. PMID:26806586

  14. Epicutaneous immunization converts subsequent and established antigen-specific T helper type 1 (Th1) to Th2-type responses.

    PubMed

    Strid, Jessica; Callard, Robin; Strobel, Stephan

    2006-09-01

    Epicutaneous immunization is a potential novel technique for topical vaccine delivery. It targets the immunologically rich milieu of the skin while having the advantage of being a non-invasive immunization procedure. By disrupting the stratum corneum of the epidermis a natural adjuvant effect can be achieved through activation of resident Langerhans cells. This negates the normal need for co-application of noxious adjuvants. Epicutaneous immunization on barrier-disrupted skin induces potent antigen-specific systemic immunity with a strong T helper type 2 (Th2) bias. We show here that epicutaneous immunization enhances the vigour of a subsequent T-cell response to the same antigen. The induced systemic Th2 response prevents the development of Th1 responses induced through injection of antigen in complete Freund's adjuvant (CFA). Prior epicutaneous immunization results in reduced production of antigen-specific interferon-gamma and immunoglobulin G2a (IgG2a) and enhanced interleukin-4, IgG1 and IgE responses to immunization with CFA. Moreover, epicutaneous immunization converts an established Th1 response to a Th2 response, as demonstrated by the specific reduction of interferon-gamma and IgG2a and the enhancement of interleukin-4 and IgE. This Th2 dominance of epicutaneous immunization may have direct therapeutic application as an immune-modulating procedure in Th1-dominant diseases such as autoimmune rheumatoid arthritis, type 1 diabetes, Hashimoto's thyroiditis and multiple sclerosis. PMID:16764688

  15. Follicular Helper T Cells in Systemic Lupus Erythematosus: Why Should They Be Considered as Interesting Therapeutic Targets?

    PubMed Central

    2016-01-01

    Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by B cell hyperactivity leading to the production of autoantibodies, some of which having a deleterious effect. Reducing autoantibody production thus represents a way of controlling lupus pathogenesis, and a better understanding of the molecular and cellular factors involved in the differentiation of B cells into plasma cells could allow identifying new therapeutic targets. Follicular helper T cells (TFH) represent a distinct subset of CD4+ T cells specialized in providing help to B cells. They are required for the formation of germinal centers and the generation of long-lived serological memory and, as such, are suspected to play a central role in SLE. Recent advances in the field of TFH biology have allowed the identification of important molecular factors involved in TFH differentiation, regulation, and function. Interestingly, some of these TFH-related molecules have been described to be dysregulated in lupus patients. In the present review, we give an overview of the aberrant expression and/or function of such key players in lupus, and we highlight their potential as therapeutic targets. PMID:27635407

  16. Neonatal BCG vaccination is associated with enhanced T-helper 1 immune responses to heterologous infant vaccines.

    PubMed

    Libraty, Daniel H; Zhang, Lei; Woda, Marcia; Acosta, Luz P; Obcena, Anamae; Brion, Job D; Capeding, Rosario Z

    2014-01-01

    Neonatal Bacille Calmette Guérin (BCG) vaccination has been reported to have beneficial effects beyond preventing infantile tuberculous meningitis and miliary disease. We hypothesized that BCG vaccine given at birth would enhance T-helper 1 (Th1) immune responses to the first vaccines given later in infancy. We conducted a nested case-control study of neonatal BCG vaccination and its heterologous Th1 immune effects in 2-3 months old infants. BCG vaccination at birth was associated with an increased frequency of interferon-γ (IFN-γ) producing spot-forming cells (SFC) to tetanus toxoid 2-3 months later. The frequency of IFN-γ producing SFC to polioviruses 1-3 also trended higher among infants who received BCG vaccination at birth. The frequency of IFN-γ+/tumor necrosis factor-α (TNF-α)+CD45RO+CD4+ T-cells upon stimulation with phorbol myristate acetate (PMA)/Ionomycin was higher in 2-3 months old infants who received BCG vaccination at birth compared to those who did not. The circulating frequency of forkhead box P3 (FoxP3)+ CD45RO+ regulatory CD4+ T-cells also trended lower in these infants. Neonatal BCG vaccination is associated with heterologous Th1 immune effects 2-3 months later. PMID:24611083

  17. Infectivity, effects on helper viruses and whitefly transmission of the deltasatellites associated with sweepoviruses (genus Begomovirus, family Geminiviridae)

    PubMed Central

    Hassan, Ishtiaq; Orílio, Anelise F.; Fiallo-Olivé, Elvira; Briddon, Rob W.; Navas-Castillo, Jesús

    2016-01-01

    Begomoviruses (family Geminiviridae) are whitefly-transmitted viruses with single-stranded DNA genomes that are frequently associated with DNA satellites. These satellites include non-coding satellites, for which the name deltasatellites has been proposed. Although the first deltasatellite was identified in the late 1990s, little is known about the effects they have on infections of their helper begomoviruses. Recently a group of deltasatellites were identified associated with sweepoviruses, a group of phylogenetically distinct begomoviruses that infect plants of the family Convolvulaceae including sweet potato. In this work, the deltasatellites associated with sweepoviruses are shown to be transreplicated and maintained in plants by the virus with which they were identified, sweet potato leaf curl virus (SPLCV). These deltasatellites were shown generally to reduce symptom severity of the virus infection by reducing virus DNA levels. Additionally they were shown to be maintained in plants, and reduce the symptoms induced by two Old World monopartite begomoviruses, tomato yellow leaf curl virus and tomato yellow leaf curl Sardinia virus. Finally one of the satellites was shown to be transmitted plant-to-plant in the presence of SPLCV by the whitefly vector of the virus, Bemisia tabaci, being the first time a deltasatellite has been shown to be insect transmitted. PMID:27453359

  18. IL-1–induced Bhlhe40 identifies pathogenic T helper cells in a model of autoimmune neuroinflammation

    PubMed Central

    Lin, Chih-Chung; Bradstreet, Tara R.; Schwarzkopf, Elizabeth A.; Jarjour, Nicholas N.; Chou, Chun; Archambault, Angela S.; Sim, Julia; Zinselmeyer, Bernd H.; Carrero, Javier A.; Wu, Gregory F.; Taneja, Reshma; Artyomov, Maxim N.; Russell, John H.

    2016-01-01

    The features that define autoreactive T helper (Th) cell pathogenicity remain obscure. We have previously shown that Th cells require the transcription factor Bhlhe40 to mediate experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. Here, using Bhlhe40 reporter mice and analyzing both polyclonal and TCR transgenic Th cells, we found that Bhlhe40 expression was heterogeneous after EAE induction, with Bhlhe40-expressing cells displaying marked production of IFN-γ, IL-17A, and granulocyte-macrophage colony-stimulating factor. In adoptive transfer EAE models, Bhlhe40-deficient Th1 and Th17 cells were both nonencephalitogenic. Pertussis toxin (PTX), a classical co-adjuvant for actively induced EAE, promoted IL-1β production by myeloid cells in the draining lymph node and served as a strong stimulus for Bhlhe40 expression in Th cells. Furthermore, PTX co-adjuvanticity was Bhlhe40 dependent. IL-1β induced Bhlhe40 expression in polarized Th17 cells, and Bhlhe40-expressing cells exhibited an encephalitogenic transcriptional signature. In vivo, IL-1R signaling was required for full Bhlhe40 expression by Th cells after immunization. Overall, we demonstrate that Bhlhe40 expression identifies encephalitogenic Th cells and defines a PTX–IL-1–Bhlhe40 pathway active in EAE. PMID:26834156

  19. Critical roles of mTOR Complex 1 and 2 for T follicular helper cell differentiation and germinal center responses

    PubMed Central

    Yang, Jialong; Lin, Xingguang; Pan, Yun; Wang, Jinli; Chen, Pengcheng; Huang, Hongxiang; Xue, Hai-Hui; Gao, Jimin; Zhong, Xiao-Ping

    2016-01-01

    T follicular helper (Tfh) cells play critical roles for germinal center responses and effective humoral immunity. We report here that mTOR in CD4 T cells is essential for Tfh differentiation. In Mtorf/f-Cd4Cre mice, both constitutive and inducible Tfh differentiation is severely impaired, leading to defective germinal center B cell formation and antibody production. Moreover, both mTORC1 and mTORC2 contribute to Tfh and GC B cell development but may do so via distinct mechanisms. mTORC1 mainly promotes CD4 T cell proliferation to reach the cell divisions necessary for Tfh differentiation, while Rictor/mTORC2 regulates Tfh differentiation by promoting Akt activation and TCF1 expression without grossly influencing T cell proliferation. Together, our results reveal crucial but distinct roles for mTORC1 and mTORC2 in CD4 T cells during Tfh differentiation and germinal center responses. DOI: http://dx.doi.org/10.7554/eLife.17936.001 PMID:27690224

  20. Follicular Helper T Cells in Systemic Lupus Erythematosus: Why Should They Be Considered as Interesting Therapeutic Targets?

    PubMed Central

    2016-01-01

    Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by B cell hyperactivity leading to the production of autoantibodies, some of which having a deleterious effect. Reducing autoantibody production thus represents a way of controlling lupus pathogenesis, and a better understanding of the molecular and cellular factors involved in the differentiation of B cells into plasma cells could allow identifying new therapeutic targets. Follicular helper T cells (TFH) represent a distinct subset of CD4+ T cells specialized in providing help to B cells. They are required for the formation of germinal centers and the generation of long-lived serological memory and, as such, are suspected to play a central role in SLE. Recent advances in the field of TFH biology have allowed the identification of important molecular factors involved in TFH differentiation, regulation, and function. Interestingly, some of these TFH-related molecules have been described to be dysregulated in lupus patients. In the present review, we give an overview of the aberrant expression and/or function of such key players in lupus, and we highlight their potential as therapeutic targets.

  1. FOXP3+ associated with the pro-inflammatory regulatory T and T helper 17 effector cells in asthma patients

    PubMed Central

    Zhang, Jian-Guo; Chen, Xiao-Juan; Liu, Tao; Jiang, Shu-Juan

    2016-01-01

    Asthma is a chronic bronchial inflammation that results to reversible incidence of airway obstruction and shortness of breath. Under normal circumstances, the lung immune system is maintained in a state of controlled inflammation, where balance exists between protective immunity mediated by effector cells and tolerance mediated by cells with regulatory function. Therefore, the inflammation observed in asthma patients may be caused by an imbalance between regulatory T (Treg) cells (CD4-positive with high expression of CD25 surface markers) and forkhead box P3 (FOXP3)-positive pro-inflammatory T helper 17 (Th17) cells. The aim of the present study was to evaluate whether reduced Treg cells and increased Th17 cells could be observed in the peripheral blood samples of asthma patients. As important markers of Treg cells, the expression levels of FOXP3 and interleukin (IL)-17a were analyzed via reverse trancription-quantitative polymerase chain reaction. The results indicated that the levels of cytokines that promote Th17 cells, including IL-6, IL-23 and TGF-β, were found to increase in the bronchoalveolar lavage fluid sample of asthma patients. However, the IL-10 level in the corresponding sample was much lower compared with that in control individuals. In conclusion, these results suggest that asthma associated with a reduced proportion of Treg and Th17 cells in the blood is characterized by the expression of pro-inflammatory cytokines that may be beneficial for the continuous generation of Th17 cells. PMID:27703517

  2. Follicular Helper T Cells in Systemic Lupus Erythematosus: Why Should They Be Considered as Interesting Therapeutic Targets?

    PubMed

    Sawaf, Matthieu; Dumortier, Hélène; Monneaux, Fanny

    2016-01-01

    Systemic lupus erythematosus (SLE) is a chronic autoimmune disease characterized by B cell hyperactivity leading to the production of autoantibodies, some of which having a deleterious effect. Reducing autoantibody production thus represents a way of controlling lupus pathogenesis, and a better understanding of the molecular and cellular factors involved in the differentiation of B cells into plasma cells could allow identifying new therapeutic targets. Follicular helper T cells (TFH) represent a distinct subset of CD4(+) T cells specialized in providing help to B cells. They are required for the formation of germinal centers and the generation of long-lived serological memory and, as such, are suspected to play a central role in SLE. Recent advances in the field of TFH biology have allowed the identification of important molecular factors involved in TFH differentiation, regulation, and function. Interestingly, some of these TFH-related molecules have been described to be dysregulated in lupus patients. In the present review, we give an overview of the aberrant expression and/or function of such key players in lupus, and we highlight their potential as therapeutic targets. PMID:27635407

  3. [Helper T cell paradigm: Th17 and regulatory T cells involved in autoimmune inflammatory disorders, pathogen defense and allergic diseases].

    PubMed

    Noma, Takeshi

    2010-01-01

    The helper T cell paradigm, divided into two distinct subsets, Th1 and Th2 cells, characterized by distinct cytokine and functions, has been expanded to IL-17-producing Th17 cells. Th1 cells producing IFN-γ are involved in delayed-type hypersensitivity, effective in intracellular pathogens defense, while Th2 cells secrete IL-4, IL-5, IL-13 and IL-25 and has a central role in IgE production, eosinophilic inflammation, and the protection for helminthic parasite infection. Th17 cell lineages, expressing IL-17 family of cytokines and IL-23-mediated functions on T cells, plays a role in immune response to fungi and extracellular pathogens and autoimmune inflammatory disorders. Th17 cells are required the combination of IL-6 and TGF-β and the transcription factors, RORC2/RORgt (mice) and STAT3 for differentiation, and produce IL-17, IL-22, IL-17F, IL-21 and CCL20. FOXP3+ regulatory T (Treg) cells produce TGF-β and IL-10, which regulate effector T cells, and thus maintain peripheral tolerance. Four functionally unique CD4+ T cells, including the regulatory T (Treg) cells are now involved in the regulation of immune responses to pathogens, self-antigens and allergens. Any defect in the entire CD4+T cell population might results in human diseases. In this review, the biology of Th17 cells and Treg cells and their role in immune diseases are presented.

  4. PU.1 Expression in T Follicular Helper Cells Limits CD40L-Dependent Germinal Center B Cell Development.

    PubMed

    Awe, Olufolakemi; Hufford, Matthew M; Wu, Hao; Pham, Duy; Chang, Hua-Chen; Jabeen, Rukhsana; Dent, Alexander L; Kaplan, Mark H

    2015-10-15

    PU.1 is an ETS family transcription factor that is important for the development of multiple hematopoietic cell lineages. Previous work demonstrated a critical role for PU.1 in promoting Th9 development and in limiting Th2 cytokine production. Whether PU.1 has functions in other Th lineages is not clear. In this study, we examined the effects of ectopic expression of PU.1 in CD4(+) T cells and observed decreased expression of genes involved with the function of T follicular helper (Tfh) cells, including Il21 and Tnfsf5 (encoding CD40L). T cells from conditional mutant mice that lack expression of PU.1 in T cells (Sfpi1(lck-/-)) demonstrated increased production of CD40L and IL-21 in vitro. Following adjuvant-dependent or adjuvant-independent immunization, we observed that Sfpi1(lck-/-) mice had increased numbers of Tfh cells, increased germinal center B cells (GCB cells), and increased Ab production in vivo. This correlated with increased expression of IL-21 and CD40L in Tfh cells from Sfpi1(lck-/-) mice compared with control mice. Finally, although blockade of IL-21 did not affect GCB cells in Sfpi1(lck-/-) mice, anti-CD40L treatment of immunized Sfpi1(lck-/-) mice decreased GCB cell numbers and Ag-specific Ig concentrations. Together, these data indicate an inhibitory role for PU.1 in the function of Tfh cells, germinal centers, and Tfh-dependent humoral immunity.

  5. Fingerprint-like Analysis of “Nanoantibody” Selection by Phage Display Using Two Helper Phage Variants

    PubMed Central

    Tillib, S.V.; Ivanova, T.I.; Vasilev, L.A.

    2010-01-01

    This paper discusses the selection of mini-antibody (nanoantibody, nanobody® or single domain antibody) sequences of desired specificity by phage display-based method using a generated library of antigen-binding domains of special heavy-chain only antibodies (single-stranded antibodies) of immunized camel. A comprehensive comparison of the efficiency of parallel selection procedures was performed by using the traditional (M13KO7) and modified (with N-terminal deletion in the surface gIII protein) helper phages. These two methods are partly complementary, and by using them in parallel one can significantly improve the selection efficiency. Parallel restriction analysis (fingerprinting) of PCR-amplified cloned sequences coding for mini-antibodies (HMR-analysis) is proposed for identifying individual clones, as a replacement to sequencing (to a certain extent). Using this method, unique data were collected on the selection of mini-antibody variants with the required specificity at various stages of a multi-stage selection procedure. It has been shown that different sequences coding for mini-antibodies are selected in different ways, and that, if this feature is not taken into account, some mini-antibody variants may be lost. PMID:22649655

  6. Infectivity, effects on helper viruses and whitefly transmission of the deltasatellites associated with sweepoviruses (genus Begomovirus, family Geminiviridae).

    PubMed

    Hassan, Ishtiaq; Orílio, Anelise F; Fiallo-Olivé, Elvira; Briddon, Rob W; Navas-Castillo, Jesús

    2016-01-01

    Begomoviruses (family Geminiviridae) are whitefly-transmitted viruses with single-stranded DNA genomes that are frequently associated with DNA satellites. These satellites include non-coding satellites, for which the name deltasatellites has been proposed. Although the first deltasatellite was identified in the late 1990s, little is known about the effects they have on infections of their helper begomoviruses. Recently a group of deltasatellites were identified associated with sweepoviruses, a group of phylogenetically distinct begomoviruses that infect plants of the family Convolvulaceae including sweet potato. In this work, the deltasatellites associated with sweepoviruses are shown to be transreplicated and maintained in plants by the virus with which they were identified, sweet potato leaf curl virus (SPLCV). These deltasatellites were shown generally to reduce symptom severity of the virus infection by reducing virus DNA levels. Additionally they were shown to be maintained in plants, and reduce the symptoms induced by two Old World monopartite begomoviruses, tomato yellow leaf curl virus and tomato yellow leaf curl Sardinia virus. Finally one of the satellites was shown to be transmitted plant-to-plant in the presence of SPLCV by the whitefly vector of the virus, Bemisia tabaci, being the first time a deltasatellite has been shown to be insect transmitted. PMID:27453359

  7. Short-term Correction of Arginase Deficiency in a Neonatal Murine Model With a Helper-dependent Adenoviral Vector

    PubMed Central

    Gau, Chia-Ling; Rosenblatt, Robin A; Cerullo, Vincenzo; Lay, Fides D; Dow, Adrienne C; Livesay, Justin; Brunetti-Pierri, Nicola; Lee, Brendan; Cederbaum, Stephen D; Grody, Wayne W; Lipshutz, Gerald S

    2009-01-01

    Neonatal gene therapy has the potential to ameliorate abnormalities before disease onset. Our gene knockout of arginase I (AI) deficiency is characterized by increasing hyperammonemia, neurological deterioration, and early death. We constructed a helper-dependent adenoviral vector (HDV) carrying AI and examined for correction of this defect. Neonates were administered 5 × 109 viral particles/g and analyzed for survival, arginase activity, and ammonia and amino acids levels. The life expectancy of arg−/− mice increased to 27 days while controls died at 14 days with hyperammonemia and in extremis. Death correlated with a decrease in viral DNA/RNA per cell as liver mass increased. Arginase assays demonstrated that vector-injected hepatocytes had ~20% activity of heterozygotes at 2 weeks of age. Hepatic arginine and ornithine in treated mice were similar to those of saline-injected heterozygotes at 2 weeks, whereas ammonia was normal. By 26 days, arginase activity in the treated arg−/− livers declined to <10%, and arginine and ornithine increased. Ammonia levels began increasing by day 25, suggesting the cause of death to be similar to that of uninjected arg−/− mice, albeit at a later time. These studies demonstrate that the AI deficient newborn mouse can be temporarily corrected and rescued using a HDV. PMID:19367256

  8. Neonatal helper-dependent adenoviral vector gene therapy mediates correction of hemophilia A and tolerance to human factor VIII

    PubMed Central

    Cela, Racel G.; Suzuki, Masataka; Lee, Brendan; Lipshutz, Gerald S.

    2011-01-01

    Neonatal gene therapy is a promising strategy for treating a number of congenital diseases diagnosed shortly after birth as expression of therapeutic proteins during postnatal life may limit the pathologic consequences and result in a potential “cure.” Hemophilia A is often complicated by the development of antibodies to recombinant protein resulting in treatment failure. Neonatal administration of vectors may avoid inhibitory antibody formation to factor VIII (FVIII) by taking advantage of immune immaturity. A helper-dependent adenoviral vector expressing human factor VIII was administered i.v. to neonatal hemophilia A knockout mice. Three days later, mice produced high levels of FVIII. Levels declined rapidly with animal growth to 5 wk of age with stable factor VIII expression thereafter to >1 y of age. Decline in factor VIII expression was not related to cell-mediated or humoral responses with lack of development of antibodies to capsid or human factor VIII proteins. Subsequent readministration and augmentation of expression was possible as operational tolerance was established to factor VIII without development of inhibitors; however, protective immunity to adenovirus remained. PMID:21245323

  9. Inhibition of G-Protein βγ Signaling Decreases Levels of Messenger RNAs Encoding Proinflammatory Cytokines in T Cell Receptor-Stimulated CD4+ T Helper Cells

    PubMed Central

    Hynes, Thomas R.; Yost, Evan A.; Hartle, Cassandra M.; Ott, Braden J.

    2015-01-01

    Background: Inhibition of G-protein βγ (Gβγ) signaling was found previously to enhance T cell receptor (TCR)-stimulated increases in interleukin 2 (IL-2) mRNA in CD4+ T helper cells, suggesting that Gβγ might be a useful drug target for treating autoimmune diseases, as low dose IL-2 therapy can suppress autoimmune responses. Because IL-2 may counteract autoimmunity in part by shifting CD4+ T helper cells away from the Type 1 T helper cell (TH1) and TH17 subtypes towards the TH2 subtype, the purpose of this study was to determine if blocking Gβγ signaling affected the balance of TH1, TH17, and TH2 cytokine mRNAs produced by CD4+ T helper cells. Methods: Gallein, a small molecule inhibitor of Gβγ, and siRNA-mediated silencing of the G-protein β1 subunit (Gβ1) were used to test the effect of blocking Gβγ on mRNA levels of cytokines in primary human TCR-stimulated CD4+ T helper cells. Results: Gallein and Gβ1 siRNA decreased interferon-γ (IFN-γ) and IL-17A mRNA levels in TCR-stimulated CD4+ T cells grown under TH1-promoting conditions. Inhibiting Gβγ also decreased mRNA levels of STAT4, which plays a positive role in TH1 differentiation and IL-17A production. Moreover, mRNA levels of the STAT4-regulated TH1-associated proteins, IL-18 receptor β chain (IL-18Rβ), mitogen-activated protein kinase kinase kinase 8 (MAP3K8), lymphocyte activation gene 3 (LAG-3), natural killer cell group 7 sequence (NKG7), and oncostatin M (OSM) were also decreased upon Gβγ inhibition. Gallein also increased IL-4, IL-5, IL-9, and IL-13 mRNA levels in TCR-stimulated memory CD4+ T cells grown in TH2-promoting conditions. Conclusions: Inhibiting Gβγ to produce these shifts in cytokine mRNA production might be beneficial for patients with autoimmune diseases such as rheumatoid arthritis (RA), Crohn’s disease (CD), psoriasis, multiple sclerosis (MS), and Hashimoto’s thyroiditis (HT), in which both IFN-γ and IL-17A are elevated. PMID:27095999

  10. Suppressive Effects of the Site 1 Protease (S1P) Inhibitor, PF-429242, on Dengue Virus Propagation.

    PubMed

    Uchida, Leo; Urata, Shuzo; Ulanday, Gianne Eduard L; Takamatsu, Yuki; Yasuda, Jiro; Morita, Kouichi; Hayasaka, Daisuke

    2016-02-01

    Dengue virus (DENV) infection causes one of the most widespread mosquito-borne diseases in the world. Despite the great need, effective vaccines and practical antiviral therapies are still under development. Intracellular lipid levels are regulated by sterol regulatory elements-binding proteins (SREBPs), which are activated by serine protease, site 1 protease (S1P). Small compound PF-429242 is known as a S1P inhibitor and the antivirus effects have been reported in some viruses. In this study, we examined the anti-DENV effects of PF-429242 using all four serotypes of DENV by several primate-derived cell lines. Moreover, emergence of drug-resistant DENV mutants was assessed by sequential passages with the drug. DENV dependency on intracellular lipids during their infection was also evaluated by adding extracellular lipids. The addition of PF-429242 showed suppression of viral propagation in all DENV serotypes. We showed that drug-resistant DENV mutants are unlikely to emerge after five times sequential passages through treatment with PF-429242. Although the levels of intracellular cholesterol and lipid droplets were reduced by PF-429242, viral propagations were not recovered by addition of exogenous cholesterol or fatty acids, indicating that the reduction of LD and cholesterol caused by PF-429242 treatment is not related to its mechanism of action against DENV propagation. Our results suggest that PF-429242 is a promising candidate for an anti-DENV agent. PMID:26875984

  11. Suppressive Effects of the Site 1 Protease (S1P) Inhibitor, PF-429242, on Dengue Virus Propagation

    PubMed Central

    Uchida, Leo; Urata, Shuzo; Ulanday, Gianne Eduard L.; Takamatsu, Yuki; Yasuda, Jiro; Morita, Kouichi; Hayasaka, Daisuke

    2016-01-01

    Dengue virus (DENV) infection causes one of the most widespread mosquito-borne diseases in the world. Despite the great need, effective vaccines and practical antiviral therapies are still under development. Intracellular lipid levels are regulated by sterol regulatory elements-binding proteins (SREBPs), which are activated by serine protease, site 1 protease (S1P). Small compound PF-429242 is known as a S1P inhibitor and the antivirus effects have been reported in some viruses. In this study, we examined the anti-DENV effects of PF-429242 using all four serotypes of DENV by several primate-derived cell lines. Moreover, emergence of drug-resistant DENV mutants was assessed by sequential passages with the drug. DENV dependency on intracellular lipids during their infection was also evaluated by adding extracellular lipids. The addition of PF-429242 showed suppression of viral propagation in all DENV serotypes. We showed that drug-resistant DENV mutants are unlikely to emerge after five times sequential passages through treatment with PF-429242. Although the levels of intracellular cholesterol and lipid droplets were reduced by PF-429242, viral propagations were not recovered by addition of exogenous cholesterol or fatty acids, indicating that the reduction of LD and cholesterol caused by PF-429242 treatment is not related to its mechanism of action against DENV propagation. Our results suggest that PF-429242 is a promising candidate for an anti-DENV agent. PMID:26875984

  12. Site-1 protease-activated formation of lysosomal targeting motifs is independent of the lipogenic transcription control[S

    PubMed Central

    Klünder, Sarah; Heeren, Jörg; Markmann, Sandra; Santer, René; Braulke, Thomas; Pohl, Sandra

    2015-01-01

    Site-1 protease (S1P) cleaves membrane-bound lipogenic sterol regulatory element-binding proteins (SREBPs) and the α/β-subunit precursor protein of the N-acetylglucosamine-1-phosphotransferase forming mannose 6-phosphate (M6P) targeting markers on lysosomal enzymes. The translocation of SREBPs from the endoplasmic reticulum (ER) to the Golgi-resident S1P depends on the intracellular sterol content, but it is unknown whether the ER exit of the α/β-subunit precursor is regulated. Here, we investigated the effect of cholesterol depletion (atorvastatin treatment) and elevation (LDL overload) on ER-Golgi transport, S1P-mediated cleavage of the α/β-subunit precursor, and the subsequent targeting of lysosomal enzymes along the biosynthetic and endocytic pathway to lysosomes. The data showed that the proteolytic cleavage of the α/β-subunit precursor into mature and enzymatically active subunits does not depend on the cholesterol content. In either treatment, lysosomal enzymes are normally decorated with M6P residues, allowing the proper sorting to lysosomes. In addition, we found that, in fibroblasts of mucolipidosis type II mice and Niemann-Pick type C patients characterized by aberrant cholesterol accumulation, the proteolytic cleavage of the α/β-subunit precursor was not impaired. We conclude that S1P substrate-dependent regulatory mechanisms for lipid synthesis and biogenesis of lysosomes are different. PMID:26108224

  13. Suppressive Effects of the Site 1 Protease (S1P) Inhibitor, PF-429242, on Dengue Virus Propagation.

    PubMed

    Uchida, Leo; Urata, Shuzo; Ulanday, Gianne Eduard L; Takamatsu, Yuki; Yasuda, Jiro; Morita, Kouichi; Hayasaka, Daisuke

    2016-02-10

    Dengue virus (DENV) infection causes one of the most widespread mosquito-borne diseases in the world. Despite the great need, effective vaccines and practical antiviral therapies are still under development. Intracellular lipid levels are regulated by sterol regulatory elements-binding proteins (SREBPs), which are activated by serine protease, site 1 protease (S1P). Small compound PF-429242 is known as a S1P inhibitor and the antivirus effects have been reported in some viruses. In this study, we examined the anti-DENV effects of PF-429242 using all four serotypes of DENV by several primate-derived cell lines. Moreover, emergence of drug-resistant DENV mutants was assessed by sequential passages with the drug. DENV dependency on intracellular lipids during their infection was also evaluated by adding extracellular lipids. The addition of PF-429242 showed suppression of viral propagation in all DENV serotypes. We showed that drug-resistant DENV mutants are unlikely to emerge after five times sequential passages through treatment with PF-429242. Although the levels of intracellular cholesterol and lipid droplets were reduced by PF-429242, viral propagations were not recovered by addition of exogenous cholesterol or fatty acids, indicating that the reduction of LD and cholesterol caused by PF-429242 treatment is not related to its mechanism of action against DENV propagation. Our results suggest that PF-429242 is a promising candidate for an anti-DENV agent.

  14. Induction of anti-allo-class I H-2 tolerance by inactivation of CD8+ helper T cells, and reversal of tolerance through introduction of third- party helper T cells

    PubMed Central

    1990-01-01

    The intravenous sensitization of C57BL/6 (B6) mice with class I H-2- disparate B6-C-H-2bm1 (bm1) spleen cells resulted in the abrogation of CD8+ T cell-mediated anti-bm1 (proliferative and interleukin 2- producing) T helper (Th) cell activities. In vitro stimulation of lymphoid cells from these mice with bm1 cells, however, generated a reduced, but appreciable, anti-bm1 cytotoxic T lymphocyte (CTL) response. Moreover, the anti-bm1 CTL response, upon stimulation with [bm1 x B6-C-H-2bm12 (bm12)]F1 spleen cells, was enhanced when compared with the response induced upon stimulation with bm1 cells. These in vitro results were reflected on in vivo graft rejection responses; bm1 skin grafts engrafted in the bm1-presensitized B6 mice exhibited prolonged survival, whereas (bm1 x bm12)F1 grafts placed collateral to bm1 grafts (dual engrafted mice) inhibited the tolerance to bm1. In the B6 mice 1-2 d after rejecting the bm1 grafts, anti-bm1 Th activities remained marginal, whereas potent anti-bm1 CTL responses were found to be generated from their spleen cells. Administration in vivo of anti- CD4 antibody into bm1-presensitized, dual graft-engrafted mice prolonged bm1 graft survival and interfered with enhanced induction of anti-bm1 CTL activity. These results indicate that anti-class I alloantigen (bm1) tolerance as induced by intravenous presensitization with the relevant antigens is not ascribed to the elimination of CD8+ CTL precursors, but to the specific inactivation of CD8+ Th cells, whose function can be bypassed by activating third-party Th cells. PMID:2141624

  15. Misfolded proteins: from little villains to little helpers in the fight against cancer.

    PubMed

    Brüning, Ansgar; Jückstock, Julia

    2015-01-01

    The application of cytostatic drugs targeting the high proliferation rates of cancer cells is currently the most commonly used treatment option in cancer chemotherapy. However, severe side effects and resistance mechanisms may occur as a result of such treatment, possibly limiting the therapeutic efficacy of these agents. In recent years, several therapeutic strategies have been developed that aim at targeting not the genomic integrity and replication machinery of cancer cells but instead their protein homeostasis. During malignant transformation, the cancer cell proteome develops vast aberrations in the expression of mutated proteins, oncoproteins, drug- and apoptosis-resistance proteins, etc. A complex network of protein quality-control mechanisms, including chaperoning by heat shock proteins (HSPs), not only is essential for maintaining the extravagant proteomic lifestyle of cancer cells but also represents an ideal cancer-specific target to be tackled. Furthermore, the high rate of protein synthesis and turnover in certain types of cancer cells can be specifically directed by interfering with the proteasomal and autophagosomal protein recycling and degradation machinery, as evidenced by the clinical application of proteasome inhibitors. Since proteins with loss of their native conformation are prone to unspecific aggregations and have proved to be detrimental to normal cellular function, specific induction of misfolded proteins by HSP inhibitors, proteasome inhibitors, hyperthermia, or inducers of endoplasmic reticulum stress represents a new method of cancer cell killing exploitable for therapeutic purposes. This review describes drugs - approved, repurposed, or under investigation - that can be used to accumulate misfolded proteins in cancer cells, and particularly focuses on the molecular aspects that lead to the cytotoxicity of misfolded proteins in cancer cells. PMID:25759792

  16. Misfolded Proteins: From Little Villains to Little Helpers in the Fight Against Cancer

    PubMed Central

    Brüning, Ansgar; Jückstock, Julia

    2015-01-01

    The application of cytostatic drugs targeting the high proliferation rates of cancer cells is currently the most commonly used treatment option in cancer chemotherapy. However, severe side effects and resistance mechanisms may occur as a result of such treatment, possibly limiting the therapeutic efficacy of these agents. In recent years, several therapeutic strategies have been developed that aim at targeting not the genomic integrity and replication machinery of cancer cells but instead their protein homeostasis. During malignant transformation, the cancer cell proteome develops vast aberrations in the expression of mutated proteins, oncoproteins, drug- and apoptosis-resistance proteins, etc. A complex network of protein quality-control mechanisms, including chaperoning by heat shock proteins (HSPs), not only is essential for maintaining the extravagant proteomic lifestyle of cancer cells but also represents an ideal cancer-specific target to be tackled. Furthermore, the high rate of protein synthesis and turnover in certain types of cancer cells can be specifically directed by interfering with the proteasomal and autophagosomal protein recycling and degradation machinery, as evidenced by the clinical application of proteasome inhibitors. Since proteins with loss of their native conformation are prone to unspecific aggregations and have proved to be detrimental to normal cellular function, specific induction of misfolded proteins by HSP inhibitors, proteasome inhibitors, hyperthermia, or inducers of endoplasmic reticulum stress represents a new method of cancer cell killing exploitable for therapeutic purposes. This review describes drugs – approved, repurposed, or under investigation – that can be used to accumulate misfolded proteins in cancer cells, and particularly focuses on the molecular aspects that lead to the cytotoxicity of misfolded proteins in cancer cells. PMID:25759792

  17. Paleogene and Cretaceous sediment cores from the Kilwa and Lindi areas of coastal Tanzania: Tanzania Drilling Project Sites 1-5

    NASA Astrophysics Data System (ADS)

    Pearson, Paul N.; Nicholas, Christopher J.; Singano, Joyce M.; Bown, Paul R.; Coxall, Helen K.; van Dongen, Bart E.; Huber, Brian T.; Karega, Amina; Lees, Jackie A.; Msaky, Emma; Pancost, Richard D.; Pearson, Marion; Roberts, Andrew P.

    2004-05-01

    -grey clay with allochthonous limestone interbeds. The site encompasses middle Eocene planktonic foraminifer Zones P12-P14 and nannofossil Zone NP17. TDP Site 5 was drilled at Machole, near Lindi, south of Kitulo Hill (10°01.646 'S, 39°41.375 'E). It yielded 31.6 m of predominantly greenish-black to dark greenish-grey clay assigned to the upper Cretaceous Globotruncana falsostuarti planktonic foraminifer zone and nannofossil zones UC15e-UC17 (upper Campanian-lower Maastrichtian). Paleomagnetic analysis suggests that the site straddles two magnetic reversals, between Chrons C32r.2r and C32r.1n. Samples from TDP Sites 1-5 yielded dinocyst and miospore assemblages that are integrated with the calcareous stratigraphy. Organic geochemical analyses of samples from each of the cores revealed biomarkers of predominantly terrestrial origin and an unusually low degree of thermal maturity, suggesting shallow burial depths. X-ray diffraction studies suggest that much of the Paleogene clay may be reworked from eroded Mesozoic formations.

  18. Induction of T helper 3 regulatory cells by dendritic cells infected with porcine reproductive and respiratory syndrome virus

    SciTech Connect

    Silva-Campa, Erika; Flores-Mendoza, Lilian; Resendiz, Monica; Pinelli-Saavedra, Araceli; Mata-Haro, Veronica; Mwangi, Waithaka; Hernandez, Jesus

    2009-05-10

    Delayed development of virus-specific immune response has been observed in pigs infected with the porcine reproductive and respiratory syndrome virus (PRRSV). Several studies support the hypothesis that the PRRSV is capable of modulating porcine immune system, but the mechanisms involved are yet to be defined. In this study, we evaluated the induction of T regulatory cells by PRRSV-infected dendritic cells (DCs). Our results showed that PRRSV-infected DCs significantly increased Foxp3{sup +}CD25{sup +} T cells, an effect that was reversible by IFN-alpha treatment, and this outcome was reproducible using two distinct PRRSV strains. Analysis of the expressed cytokines suggested that the induction of Foxp3{sup +}CD25{sup +} T cells is dependent on TGF-beta but not IL-10. In addition, a significant up-regulation of Foxp3 mRNA, but not TBX21 or GATA3, was detected. Importantly, our results showed that the induced Foxp3{sup +}CD25{sup +} T cells were able to suppress the proliferation of PHA-stimulated PBMCs. The T cells induced by the PRRSV-infected DCs fit the Foxp3{sup +}CD25{sup +} T helper 3 (Th3) regulatory cell phenotype described in the literature. The induction of this cell phenotype depended, at least in part, on PRRSV viability because IFN-alpha treatment or virus inactivation reversed these effects. In conclusion, this data supports the hypothesis that the PRRSV succeeds to establish and replicate in porcine cells early post-infection, in part, by inducing Th3 regulatory cells as a mechanism of modulating the porcine immune system.

  19. PD-1(+) and follicular helper T cells are responsible for persistent HIV-1 transcription in treated aviremic individuals.

    PubMed

    Banga, Riddhima; Procopio, Francesco Andrea; Noto, Alessandra; Pollakis, Georgios; Cavassini, Matthias; Ohmiti, Khalid; Corpataux, Jean-Marc; de Leval, Laurence; Pantaleo, Giuseppe; Perreau, Matthieu

    2016-07-01

    The mechanisms responsible for the persistence of HIV-1 after many years of suppressive antiretroviral therapy (ART) have been only partially elucidated. Most of the studies investigating HIV-1 persistence have been performed with blood, although it is well known that germinal centers (GCs) within lymph nodes (LNs) serve as primary sites for HIV-1 replication. We sought to identify the memory CD4 T cell populations in blood and LNs that are responsible for the production of replication-competent and infectious HIV-1, as well as for active and persistent virus transcription in ART-treated (for 1.5-14.0 years), aviremic (<50 HIV RNA copies/ml) HIV-infected individuals. We demonstrate that LN CD4 T cells that express programmed cell death 1 (PDCD1; also known as PD-1), which are composed of about 65% T follicular helper cells as defined by the expression of the cell surface receptors CXCR5 and PD-1, are the major source of replication-competent HIV-1 and of infectious virus, as compared to any other (CXCR5(-)PD-1(-) and CXCR5(+)PD-1(-)) blood or LN memory CD4 T cell populations. LN PD-1(+) cells accounted for 46% and 96% of the total pools of memory CD4 T cells containing inducible replication-competent or infectious virus, respectively. Notably, higher levels of cell-associated HIV-1 RNA were present in LN PD-1(+) cells after long-term (up to 12 years) ART than in other memory CD4 T cell subpopulations. These results indicate that LN PD-1(+) cells are the major CD4 T cell compartment in the blood and LNs for the production of replication-competent and infectious HIV-1, and for active and persistent virus transcription in long-term-ART-treated aviremic individuals. Thus, these cells may represent a major obstacle to finding a functional cure for HIV-1 infection. PMID:27239760

  20. Splenic Long-Lived Plasma Cells Promote the Development of Follicular Helper T Cells during Autoimmune Responses.

    PubMed

    Jang, Eunkyeong; Cho, Wang Sik; Oh, Yeon-Kyung; Cho, Mi-La; Kim, Jung Mogg; Paik, Doo-Jin; Youn, Jeehee

    2016-02-01

    Long-lived plasma cells (LLPCs) develop under the help of follicular helper T (Tfh) cells and reside mainly in the bone marrow. However, these cells are unusually abundant in the spleen of several autoimmune models including K/BxNsf mice, yet their pathogenic impact remains unknown. To investigate a previously unappreciated role of splenic LLPCs, we sorted splenic plasma cells (PCs) from K/BxNsf and K/BxN mice, corresponding to LLPCs and conventional short-lived PCs, respectively, and compared their phenotypes and ability to prime and induce the differentiation of naive CD4(+) T cells into effector cells in vitro and in vivo. We found that K/BxNsf PCs had lower levels of the Ag presentation machinery and costimulators than K/BxN PCs, and also a lower CD4(+) T cell priming capacity. Autoantigen-pulsed K/BxNsf PCs selectively polarized cognate CD4(+) T cells toward the expression of molecules necessary for Tfh development and function. As a result, the K/BxNsf PC-primed CD4(+) T cells were more effective in stimulating B cells to produce autoantigen-specific IgGs than K/BxN PCs or even dendritic cells. Adoptive transfer of K/BxNsf PCs, but not K/BxN PCs, to K/BxN mice increased numbers of Tfh cells in draining lymph nodes. These results propose that abnormal accumulation of LLPCs in the spleen of autoimmune models drives the differentiation of autoantigen-primed CD4(+) T cells to Tfh cells. This positive feedback loop between splenic LLPCs and Tfh cells may contribute to the persistence of humoral autoimmunity. PMID:26729802

  1. Neurons can be labeled with unique hues by helper virus-free HSV-1 vectors expressing Brainbow

    PubMed Central

    Zhang, Guo-rong; Zhao, Hua; Abdul-Muneer, P. M.; Cao, Haiyan; Li, Xu; Geller, Alfred I.

    2014-01-01

    Background A central problem in neuroscience is elucidating synaptic connections, the connectome. Because mammalian forebrains contain many neurons, labeling specific neurons with unique tags is desirable. A novel technology, Brainbow, creates hundreds of hues by combinatorial expression of multiple fluorescent proteins (FPs). New method We labeled small numbers of neurons, and their axons, with unique hues, by expressing Brainbow from a helper virus-free Herpes Simplex Virus (HSV-1) vector. Results The vector expresses a Brainbow cassette containing four FPs from a glutamatergic-specific promoter. Packaging HSV-brainbow produced arrays of seven to eight Brainbow cassettes, and using Cre, each FP gene was in a position to be expressed, in different cassettes. Delivery into rat postrhinal (POR) cortex or hippocampus labeled small numbers of neurons with different, often unique, hues. An area innervated by POR cortex, perirhinal (PER) cortex, contained axons with different hues. Specific axons in PER cortex were matched to specific cell bodies in POR cortex, using hue. Comparison with existing methods HSV-Brainbow is the only technology for labeling small numbers of neurons with unique hues. In Brainbow mice, many neurons contain the same hue. Brainbow-adeno-associated virus vectors require transduction of the same neuron with multiple vector particles, confounding neuroanatomical studies. Replication-competent Brainbow-pseudorabies virus vectors label multiple neurons with the same hue. Conclusions Attractive properties of HSV-Brainbow include each vector particle contains multiple cassettes, representing numerous hues, recombination products are stabile, and experimental control of the number of labeled neurons. Labeling neurons with unique hues will benefit mapping forebrain circuits. PMID:25448383

  2. Augmentation of Circulating Follicular Helper T Cells and Their Impact on Autoreactive B Cells in Myasthenia Gravis.

    PubMed

    Zhang, Cun-Jin; Gong, Ye; Zhu, Wenli; Qi, Yuan; Yang, Chun-Sheng; Fu, Ying; Chang, Guoqiang; Li, Yujing; Shi, Samuel; Wood, Kristofer; Ladha, Shafeeq; Shi, Fu-Dong; Liu, Qiang; Yan, Yaping

    2016-10-01

    Myasthenia gravis (MG) is a chronic humoral immunity-mediated autoimmune disorder of the neuromuscular junction characterized by muscle weakness. Follicular helper T (Tfh) cells may be the key Th cell subset that promotes MG development, as their major function is helping B cell activation and Ab production. Aberrance of thymus-derived Tfh cells might be implicated in autoimmune diseases including MG; just how circulating Tfh cells, especially those from patients with a normal thymus, contribute to MG pathogenesis remains to be uncovered. In this article, we characterize a population of circulating CD4(+)CXCR5(+)PD-1(+) Tfh cells in ocular and generalized MG patients without thymic abnormalities and demonstrate that the circulating Tfh cells are significantly enriched in generalized MG patients but not in ocular MG patients compared with healthy subjects, whereas a proportion of follicular regulatory T cells decreased in MG patients. In addition, the frequency of plasma cells and B cells was higher and the serum levels of IL-6/IL-21 were also elevated in these MG patients. The activated Tfh1 and Tfh17 in Tfh cells are the major source for IL-21 production in MG patients. A strong correlation between Tfh cells and the plasma cell frequency and anti-acetylcholine receptor Ab titers was evident in generalized MG patients. In particular, we found that Tfh cells derived from MG patients promoted B cells to produce Abs in an IL-21 signaling-dependent manner. Collectively, our results suggest that circulating Tfh cells may act on autoreactive B cells and thus contribute to the development of MG in patients without thymic abnormalities. PMID:27543617

  3. Overexpression of endothelial nitric oxide synthase improves endothelium-dependent vasodilation in arteries infused with helper-dependent adenovirus.

    PubMed

    Jiang, Bo; Du, Liang; Flynn, Rowan; Dronadula, Nagadhara; Zhang, Jingwan; Kim, Francis; Dichek, David

    2012-11-01

    Adenoviral vectors (Ad) are useful tools for in vivo gene transfer into endothelial cells. However, endothelium-dependent vasodilation is impaired after Ad infusion, and this impairment is not prevented by use of advanced-generation "helper-dependent" (HD) Ad that lack all viral genes. We hypothesized that endothelium-dependent vasodilation could be improved in Ad-infused arteries by overexpression of endothelial nitric oxide synthase (eNOS). We tested this hypothesis in hyperlipidemic, atherosclerosis-prone rabbits because HDAd will likely be used for treating and preventing atherosclerosis. Moreover, the consequences of eNOS overexpression might differ in normal and atherosclerosis-prone arteries and could include atherogenic effects, as reported in transgenic mice. We cloned rabbit eNOS and constructed an HDAd that expresses it. HDAdeNOS increased NO production by cultured endothelial cells and increased arterial eNOS mRNA in vivo by ∼10-fold. Compared to arteries infused with a control HDAd, HDAdeNOS-infused arteries of hyperlipidemic rabbits had significantly improved endothelium-dependent vasodilation, and similar responses to phenylephrine and nitroprusside. Moreover, infusion of HDAdeNOS had local atheroprotective effects including large, significant decreases in intimal lipid accumulation and arterial tumor necrosis factor (TNF)-α expression (p≤0.04 for both). HDAdeNOS infusion yields a durable (≥2 weeks) increase in arterial eNOS expression, improves vasomotor function, and reduces artery wall inflammation and lipid accumulation. Addition of an eNOS expression cassette improves the performance of HDAd, has no harmful effects, and may reduce atherosclerotic lesion growth.

  4. Lifelong elimination of hyperbilirubinemia in the Gunn rat with a single injection of helper-dependent adenoviral vector

    PubMed Central

    Toietta, Gabriele; Mane, Viraj P.; Norona, Wilma S.; Finegold, Milton J.; Ng, Philip; McDonagh, Antony F.; Beaudet, Arthur L.; Lee, Brendan

    2005-01-01

    Crigler–Najjar syndrome is a recessively inherited disorder characterized by severe unconjugated hyperbilirubinemia caused by a deficiency of uridine diphospho-glucuronosyl transferase 1A1. Current therapy relies on phototherapy to prevent kernicterus, but liver transplantation presently is the only permanent cure. Gene therapy is a potential alternative, and recent work has shown that helper-dependent adenoviral (HD-Ad) vectors, devoid of all viral coding sequences, induce prolonged transgene expression and exhibit significantly less chronic toxicity than early-generation Ad vectors. We used a HD-Ad vector to achieve liver-restricted expression of human uridine diphospho-glucuronosyl transferase 1A1 in the Gunn rat, a model of the human disorder. Total plasma bilirubin levels were reduced from >5.0 mg/dl to «1.4 mg/dl for >2 yr after a single i.v. administration of vector expressing the therapeutic transgene at a dose of 3 × 1012 viral particles per kg. HPLC analysis of bile from treated rats showed the presence of bilirubin glucuronides at normal WT levels >2 yr after one injection of vector, and i.v. injection of bilirubins IIIα and XIIIα in the same animals revealed excess bilirubin-conjugating capacity. There was no significant elevation of liver enzymes (alanine aminotransferase) and only transient, moderate thrombocytopenia after injection of the vector. A clinically significant reduction in serum bilirubin was observed with a dose as low as 6 × 1011 viral particles per kg. We conclude that complete, long-term correction of hyperbilirubinemia in the Gunn rat model of Crigler–Najjar syndrome can be achieved with one injection of HD-Ad vector and negligible chronic toxicity. PMID:15753292

  5. Correction of Hyperbilirubinemia in Gunn Rats Using Clinically Relevant Low Doses of Helper-Dependent Adenoviral Vectors

    PubMed Central

    Dimmock, David; Brunetti-Pierri, Nicola; Palmer, Donna J.; Beaudet, Arthur L.

    2011-01-01

    Abstract Crigler–Najjar syndrome type I is a severe inborn error of bilirubin metabolism caused by a complete deficiency of uridine diphospho-glucuronosyl transferase 1A1 (UGT1A1) and results in life-threatening unconjugated hyperbilirubinemia. Lifelong correction of hyperbilirubinemia by liver-directed gene therapy using a helper-dependent adenoviral (HDAd) vector has been previously reported in the Gunn rat, a model of Crigler–Najjar syndrome, but was only achieved using high doses (≥3 × 1012 viral particles [vp]/kg), which are likely to elicit a severe toxic response in humans. Therefore, in this study, we investigate strategies to achieve correction of hyperbilirubinemia in the Gunn rat using clinically relevant low HDAd doses. We have found that correction of hyperbilirubinemia in the Gunn rat can be achieved with a low dose of 5 × 1011 vp/kg by using an HDAd vector bearing a more potent UGT1A1 expression cassette. Furthermore, by using hydrodynamic injection of the improved HDAd vector, correction of hyperbilirubinemia in the Gunn rat can be achieved using an even lower dose of 5 × 1010 vp/kg. Although hydrodynamic injection as performed in rats is not acceptable in humans, clinically attractive, minimally invasive methods have been successfully developed to mimic hydrodynamic injection of HDAd vector in non-human primates. Therefore, using an improved expression cassette combined with a more efficient method of vector delivery permits correction of hyperbilirubinemia in the Gunn rat using clinically relevant low HDAd doses and may thus pave the way to clinical application of HDAd vectors for Crigler–Najjar syndrome gene therapy. PMID:20973621

  6. Lifelong elimination of hyperbilirubinemia in the Gunn rat with a single injection of helper-dependent adenoviral vector.

    PubMed

    Toietta, Gabriele; Mane, Viraj P; Norona, Wilma S; Finegold, Milton J; Ng, Philip; McDonagh, Antony F; Beaudet, Arthur L; Lee, Brendan

    2005-03-15

    Crigler-Najjar syndrome is a recessively inherited disorder characterized by severe unconjugated hyperbilirubinemia caused by a deficiency of uridine diphospho-glucuronosyl transferase 1A1. Current therapy relies on phototherapy to prevent kernicterus, but liver transplantation presently is the only permanent cure. Gene therapy is a potential alternative, and recent work has shown that helper-dependent adenoviral (HD-Ad) vectors, devoid of all viral coding sequences, induce prolonged transgene expression and exhibit significantly less chronic toxicity than early-generation Ad vectors. We used a HD-Ad vector to achieve liver-restricted expression of human uridine diphospho-glucuronosyl transferase 1A1 in the Gunn rat, a model of the human disorder. Total plasma bilirubin levels were reduced from >5.0 mg/dl to <1.4 mg/dl for >2 yr after a single i.v. administration of vector expressing the therapeutic transgene at a dose of 3 x 10(12) viral particles per kg. HPLC analysis of bile from treated rats showed the presence of bilirubin glucuronides at normal WT levels >2 yr after one injection of vector, and i.v. injection of bilirubins IIIalpha and XIIIalpha in the same animals revealed excess bilirubin-conjugating capacity. There was no significant elevation of liver enzymes (alanine aminotransferase) and only transient, moderate thrombocytopenia after injection of the vector. A clinically significant reduction in serum bilirubin was observed with a dose as low as 6 x 10(11) viral particles per kg. We conclude that complete, long-term correction of hyperbilirubinemia in the Gunn rat model of Crigler-Najjar syndrome can be achieved with one injection of HD-Ad vector and negligible chronic toxicity. PMID:15753292

  7. Differential T-Helper Cell Polarization after Allergen-Specific Stimulation of Autologous Dendritic Cells in Polysensitized Allergic Patients

    PubMed Central

    Ashjaei, Kazem; Bublin, Merima; Smole, Ursula; Lengger, Nina; Hafner, Christine; Breiteneder, Heimo; Wagner, Stefan; Hoffmann-Sommergruber, Karin

    2016-01-01

    Background Dendritic cells (DCs) play an important role in the induction and regulation of adaptive immune responses by polarizing T-helper (Th) cells. In allergic disease this response is dominated by Th2 cells. It is still unclear whether the activation of Th cells by DCs in atopic individuals is allergen specific. Methods Monocyte-derived DCs (MoDCs) obtained from polysensitized patients were stimulated with purified Bet v 1, Phl p 5 and Act d 10, and the surface marker expression was analysed. Proliferation and cytokine profiles of autologous naïve CD4+ T cells co-cultured with allergen-pulsed MoDCs were assessed. Results The addition of either Bet v 1 or Phl p 5 did not further increase the expression of surface markers from matured MoDCs in all study groups. In co-cultures, autologous naïve CD4+ T cells proliferated when DCs obtained from individuals allergic to birch and grass pollen were stimulated with Bet v 1 and Phl p 5, respectively. In the co-culture supernatants, significantly increased levels of IL-5 and IL-13 were detected. This effect correlated with the sensitization background and was absent when applying an unspecific allergen, Act d 10. The levels of IL-10 in supernatants of MoDCs and the levels of IL-10 and IFN-γ in supernatants of T cells remained unchanged upon stimulation with allergens. Conclusions In this study we observed that allergen-specific stimulation of MoDCs induces T-cell proliferation and upregulation of Th2-type cytokines. Interestingly, this Th2 polarization was only observed in cells stimulated with the allergen to which the patients were sensitized. PMID:25792188

  8. A New Defective Helper RNA to Produce Recombinant Sindbis Virus that Infects Neurons but does not Propagate.

    PubMed

    Kebschull, Justus M; Garcia da Silva, Pedro; Zador, Anthony M

    2016-01-01

    Recombinant Sindbis viruses are important tools in neuroscience because they combine rapid and high transgene expression with a capacity to carry large transgenes. Currently, two packaging systems based on the defective helper (DH) RNAs DH(26S)5'SIN and DH-BB(tRNA;TE12) are available for generating recombinant Sindbis virus that is neurotropic (able to infect neurons and potentially other cells). Both systems produce a fraction of viral particles that can propagate beyond the primary infected neuron. When injected into mouse brain, viruses produced using these DH RNAs produce transgene expression at the injection site, but also elsewhere in the brain. Such ectopic labeling caused recombinant Sindbis viruses to be classified as anterograde viruses with limited retrograde spread, and can complicate the interpretation of neuroanatomical and other experiments. Here we describe a new DH RNA, DH-BB(5'SIN;TE12ORF), that can be used to produce virus that is both neurotropic and propagation-incompetent. We show in mice that DH-BB(5'SIN;TE12ORF)-packaged virus eliminates infection of cells outside the injection site. We also provide evidence that ectopically labeled cells observed in previous experiments with recombinant Sindbis virus resulted from secondary infection by propagation-competent virus, rather than from inefficient retrograde spread. Virus produced with our new packaging system retains all the advantages of previous recombinant Sindbis viruses, but minimizes the risks of confounding results with unwanted ectopic labeling. It should therefore be considered in future studies in which a neurotropic, recombinant Sindbis virus is needed. PMID:27252627

  9. The Induction of IL-33 in the Sinus Epithelium and Its Influence on T-Helper Cell Responses

    PubMed Central

    Soyka, Michael B.; Holzmann, David; Basinski, Tomasz M.; Wawrzyniak, Marcin; Bannert, Christina; Bürgler, Simone; Akkoc, Tunc; Treis, Angela; Rückert, Beate; Akdis, Mübeccel; Akdis, Cezmi A.; Eiwegger, Thomas

    2015-01-01

    Background Chronic rhinosinusitis (CRS) is characterized by epithelial activation and chronic T-cell infiltration in sinonasal mucosa and nasal polyps. IL-33 is a new cytokine of the IL-1 cytokine family that has a pro-inflammatory and Th2 type cytokine induction property. The role of IL-33 in the pathomechanisms of CRS and its interaction with other T cell subsets remain to be fully understood. Methods The main trigger for IL-33 mRNA expression in primary human sinonasal epithelial cells was determined in multiple cytokine and T-cell stimulated cultures. The effects of IL-33 on naïve, Th0 and memory T-cells was studied by PCR, ELISA and flow cytometry. Biopsies from sinus tissue were analyzed by PCR and immunofluorescence for the presence of different cytokines and receptors with a special focus on IL-33. Results IL-33 was mainly induced by IFN-γ in primary sinonasal epithelial cells, and induced a typical CRSwNP Th2 favoring cytokine profile upon co-culture with T-helper cell subsets. IL-33 and its receptor ST2 were highly expressed in the inflamed epithelial tissue of CRS patients. While IL-33 was significantly up-regulated in the epithelium for CRSsNP, its receptor was higher expressed in sinus tissue from CRSwNP. Conclusions The present study delineates the influence of IL-33 in upper airway epithelium and a potential role of IL-33 in chronic inflammation of CRSwNP by enhancing Th2 type cytokine production, which could both contribute to a further increase of an established Th2 profile in CRSwNP. PMID:25932636

  10. Type 1 T-helper cell predominance and interleukin-12 expression in the gut of patients with Crohn's disease.

    PubMed Central

    Parronchi, P.; Romagnani, P.; Annunziato, F.; Sampognaro, S.; Becchio, A.; Giannarini, L.; Maggi, E.; Pupilli, C.; Tonelli, F.; Romagnani, S.

    1997-01-01

    Crohn's disease (CD) is a chronic bowel inflammatory disorder in which the pathogenic role of immune alterations has been suggested, but the immunologic mechanisms responsible for the inflammatory reaction are still poorly understood. We investigated the profile of cytokine secretion by T-cell clones generated from gut tissue specimens of four patients with active CD, five patients with ulcerative colitis, and four patients with noninflammatory gut disorders (NIGDs). The great majority of CD4+ T-cell clones generated from the gut of patients with CD produced high levels of interferon-gamma (IFN-gamma) but low or undetectable amounts of interleukin-4 (IL-4), whereas substantial proportions of CD4+ T-cell clones derived from the gut of patients with either ulcerative colitis or NIGDs produced IL-4 in addition to IFN-gamma. The immunohistochemical analysis revealed high numbers of activated CD4+ T cells showing IFN-gamma but not IL-4 reactivity, as well as substantial proportions of IL-12-containing macrophages, in the intestinal lamina propria and muscularis propria of patients with CD, whereas these cells were very rare or undetectable in patients with NIGDs. Culturing T cells from gut biopsy specimens of a patient with CD in the presence of a neutralizing anti-IL-12 antibody down-regulated the development of IFN-gamma-producing CD4+ T cells. These findings suggest that a critical event in the initiation of bowel inflammatory lesions in CD may involve up-regulation of IL-12 production, resulting in conditions that maximally promote type 1 T-helper immune responses. Images Figure 2 PMID:9060820

  11. A New Defective Helper RNA to Produce Recombinant Sindbis Virus that Infects Neurons but does not Propagate

    PubMed Central

    Kebschull, Justus M.; Garcia da Silva, Pedro; Zador, Anthony M.

    2016-01-01

    Recombinant Sindbis viruses are important tools in neuroscience because they combine rapid and high transgene expression with a capacity to carry large transgenes. Currently, two packaging systems based on the defective helper (DH) RNAs DH(26S)5’SIN and DH-BB(tRNA;TE12) are available for generating recombinant Sindbis virus that is neurotropic (able to infect neurons and potentially other cells). Both systems produce a fraction of viral particles that can propagate beyond the primary infected neuron. When injected into mouse brain, viruses produced using these DH RNAs produce transgene expression at the injection site, but also elsewhere in the brain. Such ectopic labeling caused recombinant Sindbis viruses to be classified as anterograde viruses with limited retrograde spread, and can complicate the interpretation of neuroanatomical and other experiments. Here we describe a new DH RNA, DH-BB(5’SIN;TE12ORF), that can be used to produce virus that is both neurotropic and propagation-incompetent. We show in mice that DH-BB(5’SIN;TE12ORF)-packaged virus eliminates infection of cells outside the injection site. We also provide evidence that ectopically labeled cells observed in previous experiments with recombinant Sindbis virus resulted from secondary infection by propagation-competent virus, rather than from inefficient retrograde spread. Virus produced with our new packaging system retains all the advantages of previous recombinant Sindbis viruses, but minimizes the risks of confounding results with unwanted ectopic labeling. It should therefore be considered in future studies in which a neurotropic, recombinant Sindbis virus is needed. PMID:27252627

  12. Characterization of influenza virus NS1 protein by using a novel helper-virus-free reverse genetic system.

    PubMed

    Enami, M; Enami, K

    2000-06-01

    We have developed a novel helper-virus-free reverse genetic system to genetically manipulate influenza A viruses. The RNPs, which were purified from the influenza A/WSN/33 (WSN) virus, were treated with RNase H in the presence of NS (nonstructural) cDNA fragments. This specifically digested the NS RNP. The NS-digested RNPs thus obtained were transfected into cells together with the in vitro-reconstituted NS RNP. The NS-digested RNPs alone did not rescue viruses; however, cotransfection with the NS RNP did. This protocol was also used to rescue the NP transfectant. We obtained two NS1 mutants, dl12 and N110, using this protocol. The dl12 NS gene contains a deletion of 12 amino acids at positions 66 to 77 near the N terminus. This virus was temperature sensitive in Madin-Darby bovine kidney (MDBK) cells as well as in Vero cells. The translation of all viral proteins as well as cellular proteins was significantly disrupted during a later time of infection at the nonpermissive temperature of 39 degrees C. The N110 mutant consists of 110 amino acids which are the N-terminal 48% of the WSN virus NS1 protein. Growth of this virus was significantly reduced at any temperature. In the virus-infected cells, translation of the M1 protein was reduced to 10 to 20% of that of the wild-type virus; however, the translation of neither the nucleoprotein nor NS1 was significantly interfered with, indicating the important role of NS1 in translational stimulation of the M1 protein.

  13. Generating HPV specific T helper cells for the treatment of HPV induced malignancies using TCR gene transfer

    PubMed Central

    2011-01-01

    Background Infection with high risk Human Papilloma Virus (HPV) is associated with cancer of the cervix, vagina, penis, vulva, anus and some cases of head and neck carcinomas. The HPV derived oncoproteins E6 and E7 are constitutively expressed in tumor cells and therefore potential targets for T cell mediated adoptive immunotherapy. Effective immunotherapy is dependent on the presence of both CD4+ and CD8+ T cells. However, low precursor frequencies of HPV16 specific T cells in patients and healthy donors hampers routine isolation of these cells for adoptive transfer purposes. An alternative to generate HPV specific CD4+ and CD8+ T cells is TCR gene transfer. Methods HPV specific CD4+ T cells were generated using either a MHC class I or MHC class II restricted TCR (from clones A9 and 24.101 respectively) directed against HPV16 antigens. Functional analysis was performed by interferon-γ secretion, proliferation and cytokine production assays. Results Introduction of HPV16 specific TCRs into blood derived CD4+ recipient T cells resulted in recognition of the relevant HPV16 epitope as determined by IFN-γ secretion. Importantly, we also show recognition of the endogenously processed and HLA-DP1 presented HPV16E6 epitope by 24.101 TCR transgenic CD4+ T cells and recognition of the HLA-A2 presented HPV16E7 epitope by A9 TCR transgenic CD4+ T cells. Conclusion Our data indicate that TCR transfer is feasible as an alternative strategy to generate human HPV16 specific CD4+ T helper cells for the treatment of patients suffering from cervical cancer and other HPV16 induced malignancies. PMID:21892941

  14. Germinal Center T Follicular Helper Cells Are Highly Permissive to HIV-1 and Alter Their Phenotype during Virus Replication.

    PubMed

    Kohler, Stephanie L; Pham, Michael N; Folkvord, Joy M; Arends, Tessa; Miller, Shannon M; Miles, Brodie; Meditz, Amie L; McCarter, Martin; Levy, David N; Connick, Elizabeth

    2016-03-15

    HIV-1 replication is concentrated within CD4(+) T cells in B cell follicles of secondary lymphoid tissues during asymptomatic disease. Limited data suggest that a subset of T follicular helper cells (TFH) within germinal centers (GC) is highly permissive to HIV-1. Whether GC TFH are the major HIV-1 virus-producing cells in vivo has not been established. In this study, we investigated TFH permissivity to HIV-1 ex vivo by spinoculating and culturing tonsil cells with HIV-1 GFP reporter viruses. Using flow cytometry, higher percentages of GC TFH (CXCR5(high)PD-1(high)) and CXCR5(+)programmed cell death-1 (PD-1)(low) cells were GFP(+) than non-GC TFH (CXCR5(+)PD-1(intermediate)) or extrafollicular (EF) (CXCR5(-)) cells. When sorted prior to spinoculation, however, GC TFH were substantially more permissive than CXCR5(+)PD-1(low) or EF cells, suggesting that many GC TFH transition to a CXCR5(+)PD-1(low) phenotype during productive infection. In situ hybridization on inguinal lymph node sections from untreated HIV-1-infected individuals without AIDS revealed higher frequencies of HIV-1 RNA(+) cells in GC than non-GC regions of follicle or EF regions. Superinfection of HIV-1-infected individuals' lymph node cells with GFP reporter virus confirmed the permissivity of follicular cells ex vivo. Lymph node immunostaining revealed 96% of CXCR5(+)CD4(+) cells were located in follicles. Within sorted lymph node cells from four HIV-infected individuals, CXCR5(+) subsets harbored 11-66-fold more HIV-1 RNA than CXCR5(-) subsets, as determined by RT PCR. Thus, GC TFH are highly permissive to HIV-1, but downregulate PD-1 and, to a lesser extent, CXCR5 during HIV-1 replication. These data further implicate GC TFH as the major HIV-1-producing cells in chronic asymptomatic HIV-1 infection. PMID:26873986

  15. Proximal glycans outside of the epitopes regulate the presentation of HIV-1 envelope gp120 helper epitopes1

    PubMed Central

    Li, Hualin; Xu, Chong-Feng; Blais, Steven; Wan, Qi; Zhang, Hui-Tang; Landry, Samuel J.; Hioe, Catarina E.

    2010-01-01

    Glycosylation of HIV-1 envelope gp120 determines not only the proper structure, but also the immune responses against this antigen. While glycans may be part of specific epitopes or shield other epitopes from T cells and antibodies, this study provides evidence for a different immunomodulatory function of glycans associated with gp120 residues N230 and N448. These glycans are required for efficient MHC class II-restricted presentation of nearby CD4 T-cell epitopes, even though they are not part of the epitopes. The glycans do not affect CD4 T cell recognition of more distant epitopes, and are not essential for the proper folding and function of gp120. Data on CD4 T-cell recognition of N448 mutants combined with proteolysis analyses and surface electrostatic potential calculation around residue N448 support the notion that N448-glycan near the epitope's C-terminus renders the site to be surface accessible and allows its efficient processing. In contrast, the N230-glycan contributes to the nearby epitope presentation at a step other than the proteolytic processing of the epitope. Hence, N-glycans can determine CD4 T-cell recognition of nearby gp120 epitopes by regulating the different steps in the MHC class II processing and presentation pathway after APCs acquire the intact gp120 antigen exogenously. Modifications of amino acids bearing glycans at the C termini of gp120 helper epitopes may prove to be a useful strategy for enhancing the immunogenicity of HIV-1 envelope gp120. PMID:19414790

  16. Basophils as a primary inducer of the T helper type 2 immunity in ovalbumin-induced allergic airway inflammation

    PubMed Central

    Zhong, Wenwei; Su, Wen; Zhang, Yanjie; Liu, Qi; Wu, Jinhong; Di, Caixia; Zhang, Zili; Xia, Zhenwei

    2014-01-01

    Antigen-induced allergic airway inflammation is mediated by T helper type 2 (Th2) cells and their cytokines, but the mechanism that initiates the Th2 immunity is not fully understood. Recent studies show that basophils play important roles in initiating Th2 immunity in some inflammatory models. Here we explored the role of basophils in ovalbumin (OVA) -induced airway allergic inflammation in BALB/c mice. We found that OVA sensitization and challenge resulted in a significant increase in the amount of basophils in blood and lung, along with the up-regulation of activation marker of CD200R. However, depletion of basophils with MAR-1 or Ba103 antibody attenuated airway inflammation, represented by the significantly decreased amount of the Th2 subset in spleen and draining lymph nodes, interlukin-4 level in lung and OVA-special immunoglobulin E (sIgE) levels in serum. On the other hand, adoptive transfer of basophils from OVA-challenged lung tissue to naive BALB/c mice provoked the Th2 immune response. In addition, pulmonary basophils from OVA-challenged mice were able to uptake DQ-OVA and express MHC class II molecules and CD40 in vivo, as well as to release interleukin-4 following stimulation by IgE–antigen complexes and promote Th2 polarization in vitro. These findings demonstrate that basophils may participate in Th2 immune responses in antigen-induced allergic airway inflammation and that they do so through facilitating antigen presentation and providing interleukin-4. PMID:24383680

  17. A Molecular Sensor To Characterize Arenavirus Envelope Glycoprotein Cleavage by Subtilisin Kexin Isozyme 1/Site 1 Protease

    PubMed Central

    Oppliger, Joel; da Palma, Joel Ramos; Burri, Dominique J.; Khatib, Abdel-Majid; Spiropoulou, Christina F.

    2015-01-01

    ABSTRACT Arenaviruses are emerging viruses including several causative agents of severe hemorrhagic fevers in humans. The advent of next-generation sequencing technology has greatly accelerated the discovery of novel arenavirus species. However, for many of these viruses, only genetic information is available, and their zoonotic disease potential remains unknown. During the arenavirus life cycle, processing of the viral envelope glycoprotein precursor (GPC) by the cellular subtilisin kexin isozyme 1 (SKI-1)/site 1 protease (S1P) is crucial for productive infection. The ability of newly emerging arenaviruses to hijack human SKI-1/S1P appears, therefore, to be a requirement for efficient zoonotic transmission and human disease potential. Here we implement a newly developed cell-based molecular sensor for SKI-1/S1P to characterize the processing of arenavirus GPC-derived target sequences by human SKI-1/S1P in a quantitative manner. We show that only nine amino acids flanking the putative cleavage site are necessary and sufficient to accurately recapitulate the efficiency and subcellular location of arenavirus GPC processing. In a proof of concept, our sensor correctly predicts efficient processing of the GPC of the newly emergent pathogenic Lujo virus by human SKI-1/S1P and defines the exact cleavage site. Lastly, we employed our sensor to show efficient GPC processing of a panel of pathogenic and nonpathogenic New World arenaviruses, suggesting that GPC cleavage represents no barrier for zoonotic transmission of these pathogens. Our SKI-1/S1P sensor thus represents a rapid and robust test system for assessment of the processing of putative cleavage sites derived from the GPCs of newly discovered arenavirus by the SKI-1/S1P of humans or any other species, based solely on sequence information. IMPORTANCE Arenaviruses are important emerging human pathogens that can cause severe hemorrhagic fevers with high mortality in humans. A crucial step in productive arenavirus

  18. Mechanism of Folding and Activation of Subtilisin Kexin Isozyme-1 (SKI-1)/Site-1 Protease (S1P).

    PubMed

    da Palma, Joel Ramos; Cendron, Laura; Seidah, Nabil Georges; Pasquato, Antonella; Kunz, Stefan

    2016-01-29

    The proprotein convertase subtilisin kexin isozyme-1 (SKI-1)/site-1 protease (S1P) is implicated in lipid homeostasis, the unfolded protein response, and lysosome biogenesis. The protease is further hijacked by highly pathogenic emerging viruses for the processing of their envelope glycoproteins. Zymogen activation of SKI-1/S1P requires removal of an N-terminal prodomain, by a multistep process, generating the mature enzyme. Here, we uncover a modular structure of the human SKI-1/S1P prodomain and define its function in folding and activation. We provide evidence that the N-terminal AB fragment of the prodomain represents an autonomous structural and functional unit that is necessary and sufficient for folding and partial activation. In contrast, the C-terminal BC fragment lacks a defined structure but is crucial for autoprocessing and full catalytic activity. Phylogenetic analysis revealed that the sequence of the AB domain is highly conserved, whereas the BC fragment shows considerable variation and seems even absent in some species. Notably, SKI-1/S1P of arthropods, like the fruit fly Drosophila melanogaster, contains a shorter prodomain comprised of full-length AB and truncated BC regions. Swapping the prodomain fragments between fly and human resulted in a fully mature and active SKI-1/S1P chimera. Our study suggests that primordial SKI-1/S1P likely contained a simpler prodomain consisting of the highly conserved AB fragment that represents an independent folding unit. The BC region appears as a later evolutionary acquisition, possibly allowing more subtle fine-tuning of the maturation process.

  19. Administration of helper-dependent adenoviral vectors and sequential delivery of different vector serotype for long-term liver-directed gene transfer in baboons

    PubMed Central

    Morral, Núria; O’Neal, Wanda; Rice, Karen; Leland, Michele; Kaplan, Johanne; Piedra, Pedro A.; Zhou, Heshan; Parks, Robin J.; Velji, Rizwan; Aguilar-Córdova, Estuardo; Wadsworth, Samuel; Graham, Frank L.; Kochanek, Stefan; Carey, K. Dee; Beaudet, Arthur L.

    1999-01-01

    The efficiency of first-generation adenoviral vectors as gene delivery tools is often limited by the short duration of transgene expression, which can be related to immune responses and to toxic effects of viral proteins. In addition, readministration is usually ineffective unless the animals are immunocompromised or a different adenovirus serotype is used. Recently, adenoviral vectors devoid of all viral coding sequences (helper-dependent or gutless vectors) have been developed to avoid expression of viral proteins. In mice, liver-directed gene transfer with AdSTK109, a helper-dependent adenoviral (Ad) vector containing the human α1-antitrypsin (hAAT) gene, resulted in sustained expression for longer than 10 months with negligible toxicity to the liver. In the present report, we have examined the duration of expression of AdSTK109 in the liver of baboons and compared it to first-generation vectors expressing hAAT. Transgene expression was limited to approximately 3–5 months with the first-generation vectors. In contrast, administration of AdSTK109 resulted in transgene expression for longer than a year in two of three baboons. We have also investigated the feasibility of circumventing the humoral response to the virus by sequential administration of vectors of different serotypes. We found that the ineffectiveness of readministration due to the humoral response to an Ad5 first-generation vector was overcome by use of an Ad2-based vector expressing hAAT. These data suggest that long-term expression of transgenes should be possible by combining the reduced immunogenicity and toxicity of helper-dependent vectors with sequential delivery of vectors of different serotypes. PMID:10536005

  20. Inhibition of G-Protein βγ Signaling Enhances T Cell Receptor-Stimulated Interleukin 2 Transcription in CD4+ T Helper Cells

    PubMed Central

    Yost, Evan A.; Hynes, Thomas R.; Hartle, Cassandra M.; Ott, Braden J.; Berlot, Catherine H.

    2015-01-01

    G-protein-coupled receptor (GPCR) signaling modulates the expression of cytokines that are drug targets for immune disorders. However, although GPCRs are common targets for other diseases, there are few GPCR-based pharmaceuticals for inflammation. The purpose of this study was to determine whether targeting G-protein βγ (Gβγ) complexes could provide a useful new approach for modulating interleukin 2 (IL-2) levels in CD4+ T helper cells. Gallein, a small molecule inhibitor of Gβγ, increased levels of T cell receptor (TCR)-stimulated IL-2 mRNA in primary human naïve and memory CD4+ T helper cells and in Jurkat human CD4+ leukemia T cells. Gβ1 and Gβ2 mRNA accounted for >99% of Gβ mRNA, and small interfering RNA (siRNA)-mediated silencing of Gβ1 but not Gβ2 enhanced TCR-stimulated IL-2 mRNA increases. Blocking Gβγ enhanced TCR-stimulated increases in IL-2 transcription without affecting IL-2 mRNA stability. Blocking Gβγ also enhanced TCR-stimulated increases in nuclear localization of nuclear factor of activated T cells 1 (NFAT1), NFAT transcriptional activity, and levels of intracellular Ca2+. Potentiation of IL-2 transcription required continuous Gβγ inhibition during at least two days of TCR stimulation, suggesting that induction or repression of additional signaling proteins during T cell activation and differentiation might be involved. The potentiation of TCR-stimulated IL-2 transcription that results from blocking Gβγ in CD4+ T helper cells could have applications for autoimmune diseases. PMID:25629163

  1. Long-term inducible expression in striatal neurons from helper virus-free HSV-1 vectors that contain the tetracycline-inducible promoter system

    PubMed Central

    Gao, Qingshen; Sun, Mei; Wang, Xiaodan; Zhang, Guo-rong; Geller, Alfred I.

    2006-01-01

    Direct gene transfer into neurons in the brain via a virus vector system has potential for both examining neuronal physiology and for developing gene therapy treatments for neurological diseases. Many of these applications require precise control of the levels of recombinant gene expression. The preferred method for controlling the levels of expression is by use of an inducible promoter system, and the tetracycline (tet)-inducible promoter system is the preferred system. Helper virus-free Herpes Simplex Virus (HSV-1) vectors have a number of the advantages, including their large size and efficient gene transfer. Also, we have reported long-term (14 months) expression from HSV-1 vectors that contain a modified neurofilament heavy gene promoter. A number of studies have reported short-term, inducible expression from helper virus-containing HSV-1 vector systems. However, long-term, inducible expression has not been reported using HSV-1 vectors. The goal of this study was to obtain long-term, inducible expression from helper virus-free HSV-1 vectors. We examined two different vector designs for adapting the tet promoter system to HSV-1 vectors. One design was an autoregulatory design; one transcription unit used a tet-regulated promoter to express the tet-regulated transcription factor tet-off, and another transcription unit used a tet-regulated promoter to express the Lac Z gene. In the other vector design, one transcription unit used the modified neurofilament heavy gene promoter to express tet-off, and another transcription unit used a tet-regulated promoter to express the Lac Z gene. The results showed that both vector designs supported inducible expression in cultured fibroblast or neuronal cell lines and for a short time (4 days) in the rat striatum. Of note, only the vector design that used the modified neurofilament promoter to express tet-off supported long-term (2 months) inducible expression in striatal neurons. PMID:16545782

  2. A Newly Emergent Turkey Arthritis Reovirus Shows Dominant Enteric Tropism and Induces Significantly Elevated Innate Antiviral and T Helper-1 Cytokine Responses

    PubMed Central

    Sharafeldin, Tamer A.; Mor, Sunil K.; Sobhy, Nader M.; Xing, Zheng; Reed, Kent M.; Goyal, Sagar M.; Porter, Robert E.

    2015-01-01

    Newly emergent turkey arthritis reoviruses (TARV) were isolated from tendons of lame 15-week-old tom turkeys that occasionally had ruptured leg tendons. Experimentally, these TARVs induced remarkable tenosynovitis in gastrocnemius tendons of turkey poults. The current study aimed to characterize the location and the extent of virus replication as well as the cytokine response induced by TARV during the first two weeks of infection. One-week-old male turkeys were inoculated orally with TARV (O’Neil strain). Copy numbers of viral genes were estimated in intestines, internal organs and tendons at ½, 1, 2, 3, 4, 7, 14 days Post inoculation (dpi). Cytokine profile was measured in intestines, spleen and leg tendons at 0, 4, 7 and 14 dpi. Viral copy number peaked in jejunum, cecum and bursa of Fabricius at 4 dpi. Copy numbers increased dramatically in leg tendons at 7 and 14 dpi while minimal copies were detected in internal organs and blood during the same period. Virus was detected in cloacal swabs at 1–2 dpi, and peaked at 14 dpi indicating enterotropism of the virus and its early shedding in feces. Elevation of IFN-α and IFN-β was observed in intestines at 7 dpi as well as a prominent T helper-1 response (IFN-γ) at 7 and 14 dpi. IFN-γ and IL-6 were elevated in gastrocnemius tendons at 14 dpi. Elevation of antiviral cytokines in intestines occurred at 7dpi when a significant decline of viral replication in intestines was observed. T helper-1 response in intestines and leg tendons was the dominant T-helper response. These results suggest the possible correlation between viral replication and cytokine response in early infection of TARV in turkeys. Our findings provide novel insights which help elucidate viral pathogenesis in turkey tendons infected with TARV. PMID:26659460

  3. Inhibition of G-protein βγ signaling enhances T cell receptor-stimulated interleukin 2 transcription in CD4+ T helper cells.

    PubMed

    Yost, Evan A; Hynes, Thomas R; Hartle, Cassandra M; Ott, Braden J; Berlot, Catherine H

    2015-01-01

    G-protein-coupled receptor (GPCR) signaling modulates the expression of cytokines that are drug targets for immune disorders. However, although GPCRs are common targets for other diseases, there are few GPCR-based pharmaceuticals for inflammation. The purpose of this study was to determine whether targeting G-protein βγ (Gβγ) complexes could provide a useful new approach for modulating interleukin 2 (IL-2) levels in CD4+ T helper cells. Gallein, a small molecule inhibitor of Gβγ, increased levels of T cell receptor (TCR)-stimulated IL-2 mRNA in primary human naïve and memory CD4+ T helper cells and in Jurkat human CD4+ leukemia T cells. Gβ1 and Gβ2 mRNA accounted for >99% of Gβ mRNA, and small interfering RNA (siRNA)-mediated silencing of Gβ1 but not Gβ2 enhanced TCR-stimulated IL-2 mRNA increases. Blocking Gβγ enhanced TCR-stimulated increases in IL-2 transcription without affecting IL-2 mRNA stability. Blocking Gβγ also enhanced TCR-stimulated increases in nuclear localization of nuclear factor of activated T cells 1 (NFAT1), NFAT transcriptional activity, and levels of intracellular Ca2+. Potentiation of IL-2 transcription required continuous Gβγ inhibition during at least two days of TCR stimulation, suggesting that induction or repression of additional signaling proteins during T cell activation and differentiation might be involved. The potentiation of TCR-stimulated IL-2 transcription that results from blocking Gβγ in CD4+ T helper cells could have applications for autoimmune diseases.

  4. Assessments of Thioridazine as a Helper Compound to Dicloxacillin against Methicillin-Resistant Staphylococcus aureus: In Vivo Trials in a Mouse Peritonitis Model

    PubMed Central

    Stenger, Michael; Hendel, Kristoffer; Bollen, Peter; Licht, Peter B.; Kolmos, Hans Jørn; Klitgaard, Janne K.

    2015-01-01

    Introduction The rise in antimicrobial resistance is a major global concern and requires new treatment strategies. The use of helper compounds, such as thioridazine (TDZ), an antipsychotic drug, in combination with traditional antibiotics must be investigated. Objectives The aim of this study was to investigate the efficacy of TDZ as a helper compound for dicloxacillin (DCX) against methicillin-resistant Staphylococcus aureus (MRSA) in vivo, and compare the combination treatment of DCX+TDZ with vancomycin (VAN). Methods Mice were inoculated with an intraperitoneal (IP) injection of MRSA (108 CFU) and treated in a 12-hour cycle for 48 hours. By termination, bacterial quantities in a peritoneal flush, spleen and kidneys were obtained. In the main trial the drugs were administered subcutaneously in five treatment groups: 1) DCX, 2) TDZ, 3) DCX+TDZ, 4) VAN, 5) SALINE. Additional smaller studies with IP administration and higher subcutaneous dosages (×1.5 and ×4) of the drugs were subsequently performed. Results In the main trial no significant differences were found between DCX+TDZ and DCX or TDZ alone (p≥0.121–0.999). VAN performed significantly better than DCX+TDZ on all bacteriological endpoints (p<0.001). Higher subcutaneous dosages of DCX and TDZ improved the antibacterial efficacy, but the combination treatment was still not significantly better than monotherapy. IP drug administration of DCX+TDZ revealed a significantly better antibacterial effect than DCX or TDZ alone (p<0.001) but not significantly different from VAN (p>0.999). Conclusion In conclusion, TDZ did not prove to be a viable helper compound for dicloxacillin against MRSA in subcutaneous systemic treatment. However, IP-administration of DCX+TDZ, directly at the infection site resulted in a synergetic effect, with efficacy comparable to that of VAN. PMID:26267376

  5. Phase I trial of a melanoma vaccine with gp100(280-288) peptide and tetanus helper peptide in adjuvant: immunologic and clinical outcomes.

    PubMed

    Slingluff, C L; Yamshchikov, G; Neese, P; Galavotti, H; Eastham, S; Engelhard, V H; Kittlesen, D; Deacon, D; Hibbitts, S; Grosh, W W; Petroni, G; Cohen, R; Wiernasz, C; Patterson, J W; Conway, B P; Ross, W G

    2001-10-01

    A melanoma vaccine composed of HLA-A2-restricted peptide YLEPGPVTA (gp100(280)), with or without a modified T-helper epitope from tetanus toxoid AQYIKANSKFIGITEL, has been evaluated in a Phase I trial to assess safety and immunological response. The vaccines were administered s.c. in either of two adjuvants, Montanide ISA-51 or QS-21, to 22 patients with high-risk resected melanoma (stage IIB-IV). Local and systemic toxicities were mild and transient. We detected CTL responses to the gp100(280) peptide in peripheral blood in 14% of patients. Helper T-cell responses to the tetanus helper peptide were detected in 79% of patients and had a Th1 cytokine profile. One patient with a CTL response to gp100 had a recurrence in a lymph node 2 years later; her nodes contained CD8+ cells reactive to gp100(280) (0.24%), which proliferated in response to peptide. The overall survival of patients is 75% (95% confidence interval, 57-94%) at 4.7 years follow-up, which compares favorably with expected survival. Four of 14 patients who completed at least six vaccines subsequently developed metastases, all of which were solitary and surgically resectable. They remain alive and clinically free of disease at last follow-up. Data from this trial demonstrate immunogenicity of the gp100(280) peptide and suggest that immune responses may persist long-term in some patients. The frequency and magnitude of the CTL response may be improved with more aggressive vaccination regimens. Although this Phase I study was not intended to evaluate clinical benefit, the excellent survival of patients on this protocol suggests the possibility of a benefit that should be assessed in future studies.

  6. T helper cells in cytotoxic T lymphocyte development: role of L3T4(+)-dependent and -independent T helper cell pathways in virus-specific and alloreactive cytotoxic T lymphocyte responses.

    PubMed

    Ciavarra, R P

    1990-02-01

    I have compared the requirements for T helper (Th) cell function during the generation of virus-specific and alloreactive cytotoxic thymus (T)-derived lymphocyte (CTL) responses. Restimulation of vesicular stomatitis virus (VSV)-immune T cells (VSV memory CTLs) with VSV-infected stimulators resulted in the generation of class I-restricted, VSV-specific CTLs. Progression of VSV memory CTLs (Lyt-1-2+) into VSV-specific CTLs required inductive signals derived from VSV-induced, Lyt-1+2- Th cells because: (i) cultures depleted by negative selection of Lyt-1+ T cells failed to generate CTLs; (ii) titration of VSV memory CTLs into a limiting dilution (LD) microculture system depleted of Th cells generated curves which were not consistent with a single limiting cell type; (iii) LD analysis of VSV memory CTLs did produce single-hit curves in the presence of Lyt-1+2- T cells sensitized against VSV; and (iv) monoclonal anti-L3T4 antibody completely abrogated CTL generation against VSV. Similar results were also obtained with Sendai virus (SV), a member of the paramyxovirus family. The notion that a class II-restricted, L3T4+ Th cell plays an obligatory role in the generation of CTLs against these viruses is also supported by the observation that purified T cell lymphoblasts (class II antigen negative) failed to function as antigen-presenting cells for CTL responses against VSV and SV. T cell lymphoblasts were efficiently lysed by class I-restricted, anti-VSV and -SV CTLs, indicating that activated T cells expressed the appropriate viral peptides for CTL recognition. Furthermore, heterogeneity in the VSV-induced Th cell population was detected by LD analysis, suggesting that at least two types of Th cells were required for the generation of an anti-VSV CTL response. VSV-induced Th cell function could not simply be replaced by exogenous IL-2 because this lymphokine induced cytotoxic cells that had the characteristics of lymphokine-activated killer (LAK) cells and not anti

  7. Effect of antigen-induced suppressor B cells on development of memory B cells, carrier-specific helper T cells, and antibody-forming cells

    SciTech Connect

    Kalinkovich, A.G.; Luganskaya, E.L.; Pinegin, B.V.

    1986-12-01

    This paper studies the presence of an Fc receptor on the surface of antigen-induced suppressor B cells (AISB), their sensitivity to antiproliferative agents, their interaction with other immunoregulator cells and with the precursors of antibody-forming cells (AFC). Mice were used in the experiments and were irradiated in a dose of 8.5 Gy (/sup 137/Cs). The effect of AISB on memory B cells is shown as is the effect of AISB on development of carrier-specific helper T cells. Also presented is the effect of AISB on development of AFC.

  8. Dichloroacetate modulates cytokines toward T helper 1 function via induction of the interleukin-12–interferon-γ pathway

    PubMed Central

    Badr, Mujtaba M; Qinna, Nidal A; Qadan, Fadi; Matalka, Khalid Z

    2014-01-01

    Background Dichloroacetate (DCA) is one of the new, promising anticancer drugs. DCA restores normal mitochondrial function and enables cancer cells to undergo apoptosis. In addition, DCA was found to modulate certain signaling pathways involving some transcription factors. The latter encouraged us to study DCA immunomodulatory activity on cytokines and their association with increasing DCA cancer cell cytotoxicity. Methods and results Cell viability assay was used to determine the effect of different concentrations of DCA on the survival of 3-methylcholanthrene (MCA) fibrosarcoma cell line. DCA decreased the percent survival of MCA fibrosarcoma in a dose-dependent manner (P<0.01). Furthermore, this percent survival was further reduced when MCA fibrosarcoma cells were cocultured with mouse splenocytes. The latter was observed at 10 mM DCA (P<0.01), and the inhibitory concentration at 50% dropped from 23 mM to 15.6 mM DCA (P<0.05). In addition, DCA significantly enhanced interferon (IFN)-γ but not interleukin (IL)-17 production levels in unstimulated and stimulated mouse spleen cells. To investigate the mechanism of DCA on IFN-γ production, DCA cytokine modulatory effect was tested on unstimulated macrophages, T-cells, and natural killer cells. DCA significantly increased IL-12 production from macrophages but did not modulate the production of IFN-γ from either T-cells or natural killer cells. Moreover, the DCA-enhancing effect on IFN-γ production was reversed by anti-IL-12 antibody. Also, the DCA cytokine modulatory effect was tested in vivo after inducing mouse skin inflammation using phorbol 12-myristate 13-acetate (PMA). DCA restored PMA-lowered IFN-γ and IL-12 levels and normalized PMA-increased transforming growth factor-β level, but it inhibited IL-10 levels even further (P<0.05). Conclusion DCA has immunomodulatory activity, mainly via activation of the IL-12–IFN-γ pathway and is able to modulate cytokines toward T helper 1 lymphocyte function. These

  9. The intensity of T cell receptor engagement determines the cytokine pattern of human allergen-specific T helper cells.

    PubMed

    Carballido, J M; Faith, A; Carballido-Perrig, N; Blaser, K

    1997-02-01

    Enhanced production of T helper (Th)2 cytokines by allergen-specific Th cells plays a major role in the induction and maintenance of IgE-mediated allergic disorders. The mechanism that triggers this type of response in atopic individuals is not fully understood. Allergen-specific human Th cell clones produce interleukin (IL)-4 and low or undetectable levels of interferon (IFN)-gamma after stimulation with low concentrations of antigen. However, these Th cell clones are capable of generating significant amounts of IFN-gamma after optimal activation through their T cell receptor (TcR). Allergen-specific Th cell clones isolated from allergic individuals required higher doses of antigen to reach the plateau of proliferation and to generate Th0 cytokine responses than their counterparts isolated from nonallergic subjects. On the other hand, if allergen was replaced by anti-CD3 monoclonal antibody (mAb), both allergic and nonallergic Th cell clones attained the highest level of proliferation and significant IFN-gamma production in response to equivalent concentrations of anti-CD3 mAb. These results indicate that the strength of T cell ligation, which can be modulated by the availability of the TcR ligand, controls the balance of Thl/Th2 cytokines produced by memory Th cells in vitro. In the particular case of bee venom phospholipase A2, it is shown that the expression of allergen-specific surface Ig on antigen-presenting B cells has little influence on antigen uptake and therefore in determining the levels of T cell activation and cytokine production. Alternatively, the affinity of particular major histocompatibility complex class II molecules on antigen-presenting cells for allergen-derived peptides might determine the amount of specific ligand presented to the Th cells and play a decisive role skewing the Th cell cytokine production towards Th1 or Th2 phenotypes. These findings, which are consistent with the changes in cytokine patterns observed following clinical

  10. Honoring our helpers

    PubMed Central

    Talanow, Roland; Giesel, Frederik

    2014-01-01

    This special issue of the Journal of Radiology Case Reports honors the reviewers who donated their time and expertise throughout the year 2013 to the high quality and success of this journal. PMID:24967015

  11. Honoring our helpers

    PubMed Central

    Talanow, Roland; Giesel, Frederik

    2016-01-01

    This special issue of the Journal of Radiology Case Reports honors the reviewers who donated their time and expertise throughout the year 2015 to the high quality and success of this journal. PMID:27200155

  12. Canine Companions and Helpers

    ERIC Educational Resources Information Center

    McIntosh, Phyllis

    2014-01-01

    This feature article highlights dog breeds that are popular in the United States and explores the health benefits and services that dogs provide to people. The article also discusses dog shows and dogs in popular culture.

  13. Maternal and postnatal dietary probiotic supplementation enhances splenic regulatory T helper cell population and reduces peanut allergen-induced hypersensitivity responses in mice.

    PubMed

    Toomer, Ondulla T; Ferguson, Martine; Pereira, Marion; Do, Andrew; Bigley, Elmer; Gaines, Dennis; Williams, Kristina

    2014-09-01

    Neonatal to early childhood is the critical period for establishing a balance of T helper 1 (Th1) versus T helper 2 (Th2) cellular immunity within the gut, which is strongly influenced by the source and establishment of gut microflora. Probiotic administration has been shown to attenuate Th2-biased cellular immunity and predisposition to food allergies. To test this hypothesis we provided ad libitum a probiotic-supplemented (Primalac 454 Feed Grade Microbials) or control diet to lactating dams with suckling pups and weaned pups until 10 weeks of age. Weaned mice were sensitized/challenged with peanut extract, saline or adjuvant at 6, 8 and 10 weeks of age. At 3, 6, 8 and 10 weeks, fecal samples were collected for microbial analysis, while blood samples were analyzed for total plasma IgE levels. At termination (10 weeks of age), splenic T lymphocyte population subtypes were determined using FACS analysis and Th1/Th2/Th17 gene expression by PCR array. Mice given the probiotic-supplemented diet had significantly enhanced probiotic fecal counts compared to controls at 3, 6, 8 and 10 weeks. Moreover, mice fed the probiotic-supplemented diet had enhanced splenic naturally occurring T regulatory cell populations, and reduced splenic gene expression of allergic mediator IL-13 compared to controls. These results provide evidence that early probiotic supplementation may provide host protection to hypersensitivity reactions to food allergens by attenuating food allergen inflammatory responses.

  14. NOD2 Signaling Contributes to the Innate Immune Response Against Helper-Dependent Adenovirus Vectors Independently of MyD88 In Vivo

    PubMed Central

    Suzuki, Masataka; Cela, Racel; Bertin, Terry K.; Sule, Gautam; Cerullo, Vincenzo; Rodgers, John R.

    2011-01-01

    Abstract We previously demonstrated that Toll-like receptor/myeloid differentiation primary response gene 88 (MyD88) signaling is required for maximal innate and acquired [T helper cell type 1 (Th1)] immune responses following systemic administration of helper-dependent adenoviral vectors (HDAds). However, MyD88-deficient mice injected with HDAdLacZ exhibited only partial reduction of innate immune cytokine expression compared with wild-type mice, suggesting MyD88-independent pathways also respond to HDAds. We now show that NOD2, a nucleotide-binding and oligomerization domain (NOD)–like receptor known to detect muramyl dipeptides in bacterial peptidoglycans, also contributes to innate responses to HDAds, but not to humoral or Th1 immune responses. We established NOD2/MyD88 double-deficient mice that, when challenged with HDAds, showed a significant reduction of the innate response compared with mice deficient for either gene singly, suggesting that NOD2 signaling contributes to the innate response independently of MyD88 signaling following systemic administration of HDAds. In addition, NOD2-deficient mice exhibited significantly higher transgene expression than did wild-type mice at an early time point (before development of an acquired response), but not at a later time point (after development of an acquired response). These results indicate that the intracellular sensor NOD2 is required for innate responses to HDAds and can limit transgene expression during early phases of infection. PMID:21561248

  15. A subset of OKT4+ peripheral T cells can generate colonies containing mixed progeny with OKT4+ helper and OKT8+ suppressor cells.

    PubMed

    Farcet, J P; Gourdin, M F; Calvo, C; Oudrhiri, N; Divine, M; Bouguet, J; Fradelizzi, D; Senik, A; Reyes, F

    1985-10-01

    The membrane phenotype of human T cell colony progenitors and that of their clonal progeny was studied for expression of the T4 and T8 determinants. Using clonal culture conditions, the colonies were grown in semi-solid agar medium from peripheral blood cells. Clonality was assessed using the glucose-6-phosphate-dehydrogenase isoenzyme marker. Combination of this marker with the culture of sorted cell fractions allowed us to ascribe the colony progenitors to a subset of OKT4+ lymphocytes. The progeny consisted of the mixture of single OKT4+, single OKT8+ and double OKT4+8+ cells, as determined by double staining. Double staining was performed on mass-harvested colony cells and on individual colonies expanded in liquid culture with fresh interleukin 2. Expression of the OKT8 positivity on colony cells deriving from OKT4+ progenitors required an interaction with radioresistant OKT8+ cells that were co-cultured with these progenitors. Furthermore, the functional capacities of the cell progeny were assayed on the pokeweed mitogen-driven immunoglobulin production by B cells. It was found that OKT4+ colony cells were helper whereas OKT8+ colony cells were suppressor cells. It is concluded that a subset of OKT4+ peripheral blood T lymphocytes can generate colonies containing both helper OKT4+ cells and suppressor OKT8+ cells. PMID:2932339

  16. T helper 2 (Th2) cell differentiation, type 2 innate lymphoid cell (ILC2) development and regulation of interleukin-4 (IL-4) and IL-13 production.

    PubMed

    Zhu, Jinfang

    2015-09-01

    Interleukin-4 (IL-4), IL-5 and IL-13, the signature cytokines that are produced during type 2 immune responses, are critical for protective immunity against infections of extracellular parasites and are responsible for asthma and many other allergic inflammatory diseases. Although many immune cell types within the myeloid lineage compartment including basophils, eosinophils and mast cells are capable of producing at least one of these cytokines, the production of these "type 2 immune response-related" cytokines by lymphoid lineages, CD4 T helper 2 (Th2) cells and type 2 innate lymphoid cells (ILC2s) in particular, are the central events during type 2 immune responses. In this review, I will focus on the signaling pathways and key molecules that determine the differentiation of naïve CD4 T cells into Th2 cells, and how the expression of Th2 cytokines, especially IL-4 and IL-13, is regulated in Th2 cells. The similarities and differences in the differentiation of Th2 cells, IL-4-producing T follicular helper (Tfh) cells and ILC2s as well as their relationships will also be discussed.

  17. Activation of resting human B cells by helper T-cell clone supernatant: characterization of a human B-cell-activating factor.

    PubMed Central

    Diu, A; Gougeon, M L; Moreau, J L; Reinherz, E L; Thèze, J

    1987-01-01

    The effects of helper T-cell clone supernatants on resting human B cells were investigated. Four different helper T-cell clones (two T4+ and two T8+) were stimulated by anti-T3 monoclonal antibodies on Sepharose beads or anti-T11(2) plus anti-T11(3) monoclonal antibodies. The supernatants from these activated clones induced the proliferation of highly purified resting B lymphocytes from the peripheral blood. The B cells exhibited a cell size and a surface-antigen pattern (4F2 antigen and transferrin receptor) of phase G0 B cells, and they were functionally resting. In response to T-cell supernatants a large fraction of the B cells enlarged and expressed 4F2 antigens and transferrin receptors. In gel filtration, the corresponding activity migrated with an apparent Mr of 12,000-15,000. Our findings strongly support the existence of a human B-cell-activating factor acting on resting B cells and causing them to enter phase G1 of the cell cycle. PMID:2962196

  18. Fucose-based PAMPs prime dendritic cells for follicular T helper cell polarization via DC-SIGN-dependent IL-27 production.

    PubMed

    Gringhuis, Sonja I; Kaptein, Tanja M; Wevers, Brigitte A; van der Vlist, Michiel; Klaver, Elsenoor J; van Die, Irma; Vriend, Lianne E M; de Jong, Marein A W P; Geijtenbeek, Teunis B H

    2014-10-03

    Dendritic cells (DCs) orchestrate antibody-mediated responses to combat extracellular pathogens including parasites by initiating T helper cell differentiation. Here we demonstrate that carbohydrate-specific signalling by DC-SIGN drives follicular T helper cell (TFH) differentiation via IL-27 expression. Fucose, but not mannose, engagement of DC-SIGN results in activation of IKKε, which collaborates with type I IFNR signalling to induce formation and activation of transcription factor ISGF3. Notably, ISGF3 induces expression of IL-27 subunit p28, and subsequent IL-27 secreted by DC-SIGN-primed DCs is pivotal for the induction of Bcl-6(+)CXCR5(+)PD-1(hi)Foxp1(lo) TFH cells, IL-21 secretion by TFH cells and T-cell-dependent IgG production by B cells. Thus, we have identified an essential role for DC-SIGN-induced ISGF3 by fucose-based PAMPs in driving IL-27 and subsequent TFH polarization, which might be harnessed for vaccination design.

  19. PD-1 Co-inhibitory and OX40 Co-stimulatory Crosstalk Regulates Helper T Cell Differentiation and Anti-Plasmodium Humoral Immunity.

    PubMed

    Zander, Ryan A; Obeng-Adjei, Nyamekye; Guthmiller, Jenna J; Kulu, Divine I; Li, Jun; Ongoiba, Aissata; Traore, Boubacar; Crompton, Peter D; Butler, Noah S

    2015-05-13

    The differentiation and protective capacity of Plasmodium-specific T cells are regulated by both positive and negative signals during malaria, but the molecular and cellular details remain poorly defined. Here we show that malaria patients and Plasmodium-infected rodents exhibit atypical expression of the co-stimulatory receptor OX40 on CD4 T cells and that therapeutic enhancement of OX40 signaling enhances helper CD4 T cell activity, humoral immunity, and parasite clearance in rodents. However, these beneficial effects of OX40 signaling are abrogated following coordinate blockade of PD-1 co-inhibitory pathways, which are also upregulated during malaria and associated with elevated parasitemia. Co-administration of biologics blocking PD-1 and promoting OX40 signaling induces excessive interferon-gamma that directly limits helper T cell-mediated support of humoral immunity and decreases parasite control. Our results show that targeting OX40 can enhance Plasmodium control and that crosstalk between co-inhibitory and co-stimulatory pathways in pathogen-specific CD4 T cells can impact pathogen clearance. PMID:25891357

  20. Type 1 T helper cells specific for Candida albicans antigens in peripheral blood and vaginal mucosa of women with recurrent vaginal candidiasis.

    PubMed

    Piccinni, Marie-Pierre; Vultaggio, Alessandra; Scaletti, Cristina; Livi, Claudia; Gomez, Maria J; Giudizi, Maria Grazia; Biagiotti, Roberta; Cassone, Antonio; Romagnani, Sergio; Maggi, Enrico

    2002-07-01

    The cytokine profile of circulating and vaginal T cells specific for immunodominant mannoprotein antigens of Candida albicans was analyzed in patients with recurrent vaginal candidiasis (RVC). Peripheral blood mononuclear cells (PBMC) from patients with RVC proliferated more than those from healthy subjects and expressed higher type 1:type 2 T helper cell cytokine ratios in response to C. albicans stimulation. A higher number of C. albicans-specific T cells was generated in PBMC from patients with RVC than in PBMC from healthy donors. C. albicans-specific T cell clones from patients with RVC produced higher levels of interferon (IFN)-gamma and lower levels of interleukin (IL)-4 than clones from control women. More important, a higher proportion of C. albicans-specific T cell clones was generated from lesional mucosa of patients with RVC than from normal mucosa, all of which produced IFN-gamma but not IL-4. These findings provide direct evidence that RVC is characterized by a highly polarized local and circulating type 1 T helper cell-like response against C. albicans antigens.

  1. Virus-lymphocyte interaction: T cells of the helper subset are infected with lymphocytic choriomeningitis virus during persistent infection in vivo.

    PubMed Central

    Ahmed, R; King, C C; Oldstone, M B

    1987-01-01

    The lifelong persistence of lymphocytic choriomeningitis virus (LCMV) in neonatally or congenitally infected mice is accompanied by a suppression of virus-specific T-cell responses. In this study, we identified the subset of T cells infected with LCMV during persistent infection in vivo. Using specific monoclonal antibodies to separate the different lymphocyte cell populations and employing both an infectious center assay and immunofluorescence to detect the virus, we found that infection is confined primarily to T cells of the helper subset (L3T4+ Lyt2-), with minimal involvement of cytotoxic T cells (Lyt2+ L3T4-) and mature B cells. About 0.54 to 1.1% of L3T4+ T cells were producing the virus, as determined by the infectious center assay. In contrast, 9.1 to 12.2% of these L3T4+ T cells contained viral antigen, as shown by immunofluorescence studies. This finding suggested that, at any given time, a substantial number of infected T cells were not producing infectious virus. This infection of T helper cells may be involved in the suppression of LCMV-specific T-cell responses observed in persistently infected mice. Images PMID:2952807

  2. Non-haem iron and the dissociation of piericidin A sensitivity from site 1 energy conservation in mitochondria from Torulopsis utilis

    PubMed Central

    Clegg, R. A.; Garland, P. B.

    1971-01-01

    1. The aerobic incubation of iron-deficient Torulopsis utilis cells for 12h under non-growing conditions results in the recovery by mitochondria of the previously absent site 1 energy conservation and sensitivity to piericidin A. 2. The recovery of piericidin A sensitivity but not site 1 is prevented by the presence of cycloheximide (100μg/ml) in the medium used for aerobic incubation of the cells. Rotenone sensitivity behaved similarly. 3. Chloramphenicol, erythromycin and tetracycline were without effect on the recovery of site 1 and piericidin A sensitivity. 4. Inclusion of 59Fe in the growth medium can be used as the basis for a highly sensitive assay for non-haem iron. 5. Iron-limited growth of T. utilis lowers the concentration of both non-haem iron and acid-labile sulphide of submitochondrial particles by over 20-fold compared with the `normal' situation with iron-supplemented glycerol-limited growth. 6. Increases in the non-haem iron and acid-labile sulphide concentrations of submitochondrial particles occur when site 1 and piericidin A sensitivity are recovered. The increase is approximately halved by the presence of cycloheximide. 7. The non-haem iron of T. utilis submitochondrial particles does not exchange with added iron. 8. Continuous culture of T. utilis at the transition between glycerol- and iron-limitation results in cells where mitochondria possess site 1 energy conservation but lack piericidin A sensitivity. 8. It is concluded, in contrast with widely held views to the opposite, that energy conservation at site 1 does not require electron flow to proceed through a piericidin A- or rotenone-sensitive route. 9. Restriction of the iron supplied to growing T. utilis to a concentration just above that required for growth limitation demonstrates that a 10- to 20-fold decrease of the `normal' non-haem iron concentration of both cells and mitochondria is without effect on the growth yield per unit of carbon source. Submitochondrial particles prepared

  3. Monocular deprivation delays the dynamic changes of phosphorylated synapsin Ia/b at site-1 in contralateral visual cortex of juvenile mice.

    PubMed

    Fu, Tao; Su, Qing; Xi, Ping; Han, Song; Li, Junfa

    2015-03-01

    Synapsins as a family of presynaptic terminal phosphoprotein participates in neuronal development, but their role in the synaptic plasticity of visual cortex is unclear. In this study, the impact of monocular deprivation (MD) on dynamic changes of isoform-specific protein expression and site 1 phosphorylation of synapsins in visual cortex of the postnatal mice were observed by using the technique of Western blot analysis. The results showed that the total (T-) protein levels of synapsins including the isoform of Ia/b, IIa/b and IIIa were about 21-26% of adult level in visual cortex of mice at postnatal 7 days (P7), and then the T-synapsin Ia/b and IIb could quickly reach adult level at P35. However, the T-synapsin IIa and IIIa increased more slowly (71-74% at P35), and then kept increasing in the visual cortex of mice at P60. Unlike to the changes of T-synapsins, the level of phosphorylated (P-) synapsin Ia/b (not IIa/b and IIIa) at site 1 increased with development to the highest level at P21, and then decreased rapidly to a low level in visual cortex of mice at P35-60. In addition, we found that the levels of P-synapsin Ia/b increased significantly in left visual cortex of P28 and P35 (not P21 and P42) mice with 1-week MD of right eye; and no significant changes of T-synapsins were observed in both left and right sides of visual cortex in P21-42 mice with MD treatment. These results suggested that the isoform-specific protein expression and site-1 phosphorylation of synapsins might play a different role in the synaptic plasticity of visual cortex, and MD delays the dynamic changes of phosphorylated synapsin Ia/b at site-1 in contralateral visual cortex of juvenile mice.

  4. Integrated Means Integrity

    ERIC Educational Resources Information Center

    Odegard, John D.

    1978-01-01

    Describes the operation of the Cessna Pilot Center (CPC) flight training systems. The program is based on a series of integrated activities involving stimulus, response, reinforcement and association components. Results show that the program can significantly reduce in-flight training time. (CP)

  5. T helper cell priming of mice to Borrelia burgdorferi OspA leads to induction of protective antibodies following experimental but not tick-borne infection.

    PubMed

    Zhong, W; Gern, L; Kramer, M; Wallich, R; Simon, M M

    1997-11-01

    Antibodies to the outer surface lipoprotein A (OspA) of Borrelia burgdorferi confer protection to SCID mice against subsequent tick-borne or experimental infection. However, OspA-specific antibodies are hardly detectable in naturally infected humans, dogs, hamsters and mice. This is most probably due to limited expression of OspA on spirochetes transmitted from the vector to the host. Here we have tested whether T cell priming of mice would lead to the induction of protective OspA-specific antibodies upon infection. It is shown that AKR/N mice, previously immunized with either a single T helper cell peptide of OspA, or a mixture of 27 peptides spanning the entire molecule, develop OspA-specific IgM or IgG antibodies, including those to a prominent protective B cell epitope of OspA. LA-2, within 7 days of infection with low doses (10(3)) of culture-derived spirochetes. In marked contrast, the same groups of pre-sensitized mice failed to generate any detectable OspA-specific antibodies after tick-borne infection for more than 40 days after infection. All mice, irrespective of their state of T cell immunity to OspA or the mode of infection, produced similar levels of OspC-specific IgM and IgG antibodies as early as day 14 after infection. None of the mice previously immunized with OspA peptides were protected against experimental infection, in spite of the appearance of protective antibodies. It is clear from these data that, in contrast to culture-derived spirochetes, the naturally transmitted pathogen fails to express OspA within the mammalian host at levels sufficient for induction of B cell responses, even in the presence of pre-activated T helper cells. Together with the fact that OspA-specific antibodies are mainly operative by eliminating spirochetes from the vector during infestation, the data suggest that OspA-vaccination for T helper cell immunity alone is not sufficient to prevent Lyme disease.

  6. Radiological dose assessment for residual radioactive material in soil at the clean slate sites 1, 2, and 3, Tonopah Test Range

    SciTech Connect

    1997-06-01

    A radiological dose assessment has been performed for Clean Slate Sites 1, 2, and 3 at the Tonopah Test Range, approximately 390 kilometers (240 miles) northwest of Las Vegas, Nevada. The assessment demonstrated that the calculated dose to hypothetical individuals who may reside or work on the Clean Slate sites, subsequent to remediation, does not exceed the limits established by the US Department of Energy for protection of members of the public and the environment. The sites became contaminated as a result of Project Roller Coaster experiments conducted in 1963 in support of the US Atomic Energy Commission (Shreve, 1964). Remediation of Clean Slate Sites 1, 2, and 3 is being performed to ensure that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works on a Clean Slate site should not exceed 100 millirems per year. The DOE residual radioactive material guideline (RESRAD) computer code was used to assess the dose. RESRAD implements the methodology described in the DOE manual for establishing residual radioactive material guidelines (Yu et al., 1993a). In May and June of 1963, experiments were conducted at Clean Slate Sites 1, 2, and 3 to study the effectiveness of earth-covered structures for reducing the dispersion of nuclear weapons material as a result of nonnuclear explosions. The experiments required the detonation of various simulated weapons using conventional chemical explosives (Shreve, 1964). The residual radioactive contamination in the surface soil consists of weapons grade plutonium, depleted uranium, and their radioactive decay products.

  7. Activation of human T-helper/inducer cell, T-cytotoxic/suppressor cell, B-cell, and natural killer (NK)-cells and induction of NK cell activity against K562 chronic myeloid leukemia cells with modified citrus pectin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background Modified citrus pectin (MCP) is known for its anti-cancer effects and its ability to be absorbed and circulated in the human body. In this report we tested the ability of MCP to induce the activation of human blood lymphocyte subsets including T-helper/inducer cell, Tcytotoxic/suppres...

  8. Integrating Art.

    ERIC Educational Resources Information Center

    BCATA Journal for Art Teachers, 1991

    1991-01-01

    These articles focus on art as a component of interdisciplinary integration. (1) "Integrated Curriculum and the Visual Arts" (Anna Kindler) considers various aspects of integration and implications for art education. (2) "Integration: The New Literacy" (Tim Varro) illustrates how the use of technology can facilitate cross-curricular integration.…

  9. A step-by-step overview of the dynamic process of epitope selection by major histocompatibility complex class II for presentation to helper T cells

    PubMed Central

    Sadegh-Nasseri, Scheherazade

    2016-01-01

    T cell antigen receptors (TCRs) expressed on cytotoxic or helper T cells can only see their specific target antigen as short sequences of peptides bound to the groove of proteins of major histocompatibility complex (MHC) class I, and class II respectively. In addition to the many steps, several participating proteins, and multiple cellular compartments involved in the processing of antigens, the MHC structure, with its dynamic and flexible groove, has perfectly evolved as the underlying instrument for epitope selection. In this review, I have taken a step-by-step, and rather historical, view to describe antigen processing and determinant selection, as we understand it today, all based on decades of intense research by hundreds of laboratories. PMID:27347387

  10. Age-related impairment of humoral response to influenza is associated with changes in antigen specific T follicular helper cell responses

    PubMed Central

    Lefebvre, Julie S; Masters, April R; Hopkins, Jacob W; Haynes, Laura

    2016-01-01

    T follicular helper (TFH) cell responses are essential for generation of protective humoral immunity during influenza infection. Aging has a profound impact on CD4+ T cell function and humoral immunity, yet the impact of aging on antigen specific TFH responses remains unclear. Influenza specific TFH cells are generated in similar numbers in young and aged animals during infection, but TFH cells from aged mice exhibit significant differences, including reduced expression of ICOS and elevated production of IL-10 and IFNγ, which potentially impairs interaction with cognate B cells. Also, more influenza specific T cells in aged mice have a regulatory phenotype, which could contribute to the impaired TFH function. Adoptive transfer studies with young T cells demonstrated that TGF-β1 in the aged environment can drive increased regulatory T cell accumulation. Aging and the aged environment thus impact antigen specific TFH cell function and formation, which contribute to reduced protective humoral responses. PMID:27109638

  11. Hydroxypropyl-β-Cyclodextrin Spikes Local Inflammation That Induces Th2 Cell and T Follicular Helper Cell Responses to the Coadministered Antigen

    PubMed Central

    Onishi, Motoyasu; Ozasa, Koji; Kobiyama, Kouji; Ohata, Keiichi; Kitano, Mitsutaka; Taniguchi, Keiichi; Homma, Tomoyuki; Kobayashi, Masanori; Sato, Akihiko; Katakai, Yuko; Yasutomi, Yasuhiro; Wijaya, Edward; Igarashi, Yoshinobu; Nakatsu, Noriyuki; Ise, Wataru; Inoue, Takeshi; Yamada, Hiroshi; Vandenbon, Alexis; Standley, Daron M.; Kurosaki, Tomohiro; Coban, Cevayir; Aoshi, Taiki; Kuroda, Etsushi

    2015-01-01

    Cyclodextrins are commonly used as a safe excipient to enhance the solubility and bioavailability of hydrophobic pharmaceutical agents. Their efficacies and mechanisms as drug-delivery systems have been investigated for decades, but their immunological properties have not been examined. In this study, we reprofiled hydroxypropyl-β-cyclodextrin (HP-β-CD) as a vaccine adjuvant and found that it acts as a potent and unique adjuvant. HP-β-CD triggered the innate immune response at the injection site, was trapped by MARCO+ macrophages, increased Ag uptake by dendritic cells, and facilitated the generation of T follicular helper cells in the draining lymph nodes. It significantly enhanced Ag-specific Th2 and IgG Ab responses as potently as did the conventional adjuvant, aluminum salt (alum), whereas its ability to induce Ag-specific IgE was less than that of alum. At the injection site, HP-β-CD induced the temporary release of host dsDNA, a damage-associated molecular pattern. DNase-treated mice, MyD88-deficient mice, and TBK1-deficient mice showed significantly reduced Ab responses after immunization with this adjuvant. Finally, we demonstrated that HP-β-CD–adjuvanted influenza hemagglutinin split vaccine protected against a lethal challenge with a clinically isolated pandemic H1N1 influenza virus, and the adjuvant effect of HP-β-CD was demonstrated in cynomolgus macaques. Our results suggest that HP-β-CD acts as a potent MyD88- and TBK1-dependent T follicular helper cell adjuvant and is readily applicable to various vaccines. PMID:25681338

  12. Early Rise of Blood T Follicular Helper Cell Subsets and Baseline Immunity as Predictors of Persisting Late Functional Antibody Responses to Vaccination in Humans

    PubMed Central

    Borgogni, Erica; Zedda, Luisanna; Cantisani, Rocco; Chiappini, Nico; Schiavetti, Francesca; Rosa, Domenico; Castellino, Flora; Montomoli, Emanuele; Bodinham, Caroline L.; Lewis, David J.; Medini, Duccio; Bertholet, Sylvie; Del Giudice, Giuseppe

    2016-01-01

    CD4+ T follicular helper cells (TFH) have been identified as the T-cell subset specialized in providing help to B cells for optimal activation and production of high affinity antibody. We recently demonstrated that the expansion of peripheral blood influenza-specific CD4+IL-21+ICOS1+ T helper (TH) cells, three weeks after vaccination, associated with and predicted the rise of protective neutralizing antibodies to avian H5N1. In this study, healthy adults were vaccinated with plain seasonal trivalent inactivated influenza vaccine (TIIV), MF59®-adjuvanted TIIV (ATIIV), or saline placebo. Frequencies of circulating CD4+ TFH1 ICOS+ TFH cells and H1N1-specific CD4+IL-21+ICOS+ CXCR5+ TFH and CXCR5- TH cell subsets were determined at various time points after vaccination and were then correlated with hemagglutination inhibition (HI) titers. All three CD4+ T cell subsets expanded in response to TIIV and ATIIV, and peaked 7 days after vaccination. To demonstrate that these TFH cell subsets correlated with functional antibody titers, we defined an alternative endpoint metric, decorrelated HI (DHI), which removed any correlation between day 28/day 168 and day 0 HI titers, to control for the effect of preexisting immunity to influenza vaccine strains. The numbers of total circulating CD4+ TFH1 ICOS+ cells and of H1N1-specific CD4+IL-21+ICOS+ CXCR5+, measured at day 7, were significantly associated with day 28, and day 28 and 168 DHI titers, respectively. Altogether, our results show that CD4+ TFH subsets may represent valuable biomarkers of vaccine-induced long-term functional immunity. Trial Registration ClinicalTrials.gov NCT01771367 PMID:27336786

  13. Quantification of High-Capacity Helper-Dependent Adenoviral Vector Genomes In Vitro and In Vivo, Using Quantitative TaqMan Real-Time Polymerase Chain Reaction

    PubMed Central

    PUNTEL, M.; CURTIN, J.F.; ZIRGER, J.M.; MUHAMMAD, A.K.M.; XIONG, W.; LIU, C.; HU, J.; KROEGER, K.M.; CZER, P.; SCIASCIA, S.; MONDKAR, S.; LOWENSTEIN, P.R.; CASTRO, M.G.

    2006-01-01

    First-generation adenoviral (Ad) and high-capacity adenoviral (HC-Ad) vectors are efficient delivery vehicles for transferring therapeutic transgenes in vivo into tissues/organs. The initial successes reported with adenoviral vectors in preclinical trials have been limited by immune-related adverse side effects. This has been, in part, attributed to the use of poorly characterized preparations of adenoviral vectors and also to the untoward immune adverse side effects elicited when high doses of these vectors were used. HC-Ads have several advantages over Ads, including the lack of viral coding sequences, which after infection and uncoating, makes them invisible to the host’s immune system. Another advantage is their large cloning capacity (up to ~35 kb). However, accurate characterization of HC-Ad vectors, and of contaminating replication-competent adenovirus (RCA) or helper virus, is necessary before these preparations can be used safely in clinical trials. Consequently, the development of accurate, simple, and reproducible methods to standardize and validate adenoviral preparations for the presence of contaminant genomes is required. By using a molecular method that allows accurate, reproducible, and simultaneous determination of HC-Ad, contaminating helper virus, and RCA genome copy numbers based on real-time quantitative PCR, we demonstrate accurate detection of these three genomic entities, within CsCl-purified vector stocks, total DNA isolated from cells transduced in vitro, and from brain tissue infected in vivo. This approach will allow accurate assessment of the levels and biodistribution of HC-Ad and improve the safety and efficacy of clinical trials. PMID:16716110

  14. Induction of Th1-Biased T Follicular Helper (Tfh) Cells in Lymphoid Tissues during Chronic Simian Immunodeficiency Virus Infection Defines Functionally Distinct Germinal Center Tfh Cells.

    PubMed

    Velu, Vijayakumar; Mylvaganam, Geetha Hanna; Gangadhara, Sailaja; Hong, Jung Joo; Iyer, Smita S; Gumber, Sanjeev; Ibegbu, Chris C; Villinger, Francois; Amara, Rama Rao

    2016-09-01

    Chronic HIV infection is associated with accumulation of germinal center (GC) T follicular helper (Tfh) cells in the lymphoid tissue. The GC Tfh cells can be heterogeneous based on the expression of chemokine receptors associated with T helper lineages, such as CXCR3 (Th1), CCR4 (Th2), and CCR6 (Th17). However, the heterogeneous nature of GC Tfh cells in the lymphoid tissue and its association with viral persistence and Ab production during chronic SIV/HIV infection are not known. To address this, we characterized the expression of CXCR3, CCR4, and CCR6 on GC Tfh cells in lymph nodes following SIVmac251 infection in rhesus macaques. In SIV-naive rhesus macaques, only a small fraction of GC Tfh cells expressed CXCR3, CCR4, and CCR6. However, during chronic SIV infection, the majority of GC Tfh cells expressed CXCR3, whereas the proportion of CCR4(+) cells did not change, and CCR6(+) cells decreased. CXCR3(+), but not CXCR3(-), GC Tfh cells produced IFN-γ (Th1 cytokine) and IL-21 (Tfh cytokine), whereas both subsets expressed CD40L following stimulation. Immunohistochemistry analysis demonstrated an accumulation of CD4(+)IFN-γ(+) T cells within the hyperplastic follicles during chronic SIV infection. CXCR3(+) GC Tfh cells also expressed higher levels of ICOS, CCR5, and α4β7 and contained more copies of SIV DNA compared with CXCR3(-) GC Tfh cells. However, CXCR3(+) and CXCR3(-) GC Tfh cells delivered help to B cells in vitro for production of IgG. These data demonstrate that chronic SIV infection promotes expansion of Th1-biased GC Tfh cells, which are phenotypically and functionally distinct from conventional GC Tfh cells and contribute to hypergammaglobulinemia and viral reservoirs. PMID:27481845

  15. ROCK2 signaling is required to induce a subset of T follicular helper cells through opposing effects on STATs in autoimmune settings.

    PubMed

    Weiss, Jonathan M; Chen, Wei; Nyuydzefe, Melanie S; Trzeciak, Alissa; Flynn, Ryan; Tonra, James R; Marusic, Suzana; Blazar, Bruce R; Waksal, Samuel D; Zanin-Zhorov, Alexandra

    2016-01-01

    Rho-associated kinase 2 (ROCK2) determines the balance between human T helper 17 (TH17) cells and regulatory T (Treg) cells. We investigated its role in the generation of T follicular helper (TFH) cells, which help to generate antibody-producing B cells under normal and autoimmune conditions. Inhibiting ROCK2 in normal human T cells or peripheral blood mononuclear cells from patients with active systemic lupus erythematosus (SLE) decreased the number and function of TFH cells induced by activation ex vivo. Moreover, inhibition of ROCK2 activity decreased the abundance of the transcriptional regulator Bcl6 (B cell lymphoma 6) and increased that of Blimp1 by reducing the binding of signal transducer and activator of transcription 3 (STAT3) and increasing that of STAT5 to the promoters of the genes Bcl6 and PRDM1, respectively. In the MRL/lpr murine model of SLE, oral administration of the selective ROCK2 inhibitor KD025 resulted in a twofold reduction in the numbers of TFH cells and antibody-producing plasma cells in the spleen, as well as a decrease in the size of splenic germinal centers, which are the sites of interaction between TFH cells and B cells. KD025-treated mice showed a substantial improvement in both histological and clinical scores compared to those of untreated mice and had reduced amounts of Bcl6 and phosphorylated STAT3, as well as increased STAT5 phosphorylation. Together, these data suggest that ROCK2 signaling plays a critical role in controlling the development of TFH cells induced by autoimmune conditions through reciprocal regulation of STAT3 and STAT5 activation. PMID:27436361

  16. Do mothers prefer helpers or smaller litters? Birth sex ratio and litter size adjustment in cotton-top tamarins (Saguinus oedipus)

    PubMed Central

    Boulton, Rebecca A; Fletcher, Alison W

    2015-01-01

    Sex allocation theory has been a remarkably productive field in behavioral ecology with empirical evidence regularly supporting quantitative theoretical predictions. Across mammals in general and primates in particular, however, support for the various hypotheses has been more equivocal. Population-level sex ratio biases have often been interpreted as supportive, but evidence for small-scale facultative adjustment has rarely been found. The helper repayment (HR) also named the local resource enhancement (LRE) hypothesis predicts that, in cooperatively breeding species, mothers invest more in the sex which assists with rearing future offspring and that this bias will be more pronounced in mothers who require extra assistance (i.e., due to inexperience or a lack of available alloparents). We tested these hypotheses in captive cotton-top tamarins (Saguinus oedipus) utilizing the international studbook and birth records obtained through a questionnaire from ISIS-registered institutions. Infant sex, litter size, mother's age, parity, and group composition (presence of nonreproductive subordinate males and females) were determined from these records. The HR hypothesis was supported over the entire population, which was significantly biased toward males (the “helpful” sex). We found little support for helper repayment at the individual level, as primiparous females and those in groups without alloparents did not exhibit more extreme tendencies to produce male infants. Primiparous females were, however, more likely to produce singleton litters. Singleton births were more likely to be male, which suggests that there may be an interaction between litter size adjustment and sex allocation. This may be interpreted as supportive of the HR hypothesis, but alternative explanations at both the proximate and ultimate levels are possible. These possibilities warrant further consideration when attempting to understand the ambiguous results of primate sex ratio studies so far

  17. Early Rise of Blood T Follicular Helper Cell Subsets and Baseline Immunity as Predictors of Persisting Late Functional Antibody Responses to Vaccination in Humans.

    PubMed

    Spensieri, Fabiana; Siena, Emilio; Borgogni, Erica; Zedda, Luisanna; Cantisani, Rocco; Chiappini, Nico; Schiavetti, Francesca; Rosa, Domenico; Castellino, Flora; Montomoli, Emanuele; Bodinham, Caroline L; Lewis, David J; Medini, Duccio; Bertholet, Sylvie; Del Giudice, Giuseppe

    2016-01-01

    CD4+ T follicular helper cells (T(FH)) have been identified as the T-cell subset specialized in providing help to B cells for optimal activation and production of high affinity antibody. We recently demonstrated that the expansion of peripheral blood influenza-specific CD4(+)IL-21(+)ICOS1(+) T helper (T(H)) cells, three weeks after vaccination, associated with and predicted the rise of protective neutralizing antibodies to avian H5N1. In this study, healthy adults were vaccinated with plain seasonal trivalent inactivated influenza vaccine (TIIV), MF59(®)-adjuvanted TIIV (ATIIV), or saline placebo. Frequencies of circulating CD4(+) T(FH)1 ICOS(+) T(FH) cells and H1N1-specific CD4(+-)IL-21(+)ICOS(+) CXCR5(+) T(FH) and CXCR5(-) T(H) cell subsets were determined at various time points after vaccination and were then correlated with hemagglutination inhibition (HI) titers. All three CD4(+) T cell subsets expanded in response to TIIV and ATIIV, and peaked 7 days after vaccination. To demonstrate that these T(FH) cell subsets correlated with functional antibody titers, we defined an alternative endpoint metric, decorrelated HI (DHI), which removed any correlation between day 28/day 168 and day 0 HI titers, to control for the effect of preexisting immunity to influenza vaccine strains. The numbers of total circulating CD4(+)T(FH)1 ICOS(+) cells and of H1N1-specific CD4(+)IL-21(+)ICOS(+) CXCR5(+), measured at day 7, were significantly associated with day 28, and day 28 and 168 DHI titers, respectively. Altogether, our results show that CD4(+) T(FH) subsets may represent valuable biomarkers of vaccine-induced long-term functional immunity. PMID:27336786

  18. Increase of human papillomavirus-16 E7-specific T helper type 1 response in peripheral blood of cervical cancer patients after radiotherapy

    PubMed Central

    Delgado, Félix Giovanni; Martínez, Elizabeth; Céspedes, María Angélica; Bravo, María Mercedes; Navas, María Cristina; Rojas, Alba Lucía Cómbita

    2009-01-01

    It has been suggested that tumour cell lysis by gamma-radiation induces a tumoral antigen release eliciting an immune response. It is not clear how a specific immune response in cervical cancer patients is developed after radiotherapy. This study is an attempt to investigate the role of the human papillomavirus type 16 (HPV-16) E7-specific T helper response before and after radiotherapy. Lymphocytes were isolated from 32 cervical cancer patients before and after radiotherapy and from 16 healthy women. They were stimulated for 12 hr with autologous HPV-16 E7-pulsed monocyte-derived dendritic cells or directly with HPV-16 E7 synthetic peptides: E751–70, E765–84 and E779–98. The cells were stained for CD4, CD69, intracellular interferon-γ (IFN-γ) and interleukin-4 (IL-4) cytokines and analysed by flow cytometry. A specific CD4+ CD69+ IFN-γ+ immune response against HPV-16 E779–98 peptide was observed in 10 of 14 patients (71·4%) after treatment, compared with 4 of 14 (28·5%) before radiotherapy (P = 0·039); however, this response was not associated with a successful clinical response. Before treatment, 5 of 31 patients showed a HPV-16 E779–98-specific T helper type 2 (Th2) response. Interestingly, this response was significantly associated with a decrease in disease-free survival (P = 0·027). These results suggest that a Th2-type cellular response could be useful as a predictor of recurrence and poor prognosis. An increase of the HPV-specific immune response was observed after radiotherapy; however, it is not enough to control completely the disease after treatment. Our results support that the E7-specific T-cell IFN-γ response in cervical cancer patients, rather than reflecting the host’s capability of controlling tumour growth, might be an indicator for disease severity. PMID:18778290

  19. T-independent and T-dependent B lymphoblasts: helper T cells prime for interleukin 2-induced growth and secretion of immunoglobulins that utilize downstream heavy chains.

    PubMed

    Forman, M S; Puré, E

    1991-03-01

    Resting B cells enlarge, enter the cell cycle, and change their surface phenotype when activated via the surface immunoglobulin (Ig) receptor, but subsequent cell growth and antibody production is relatively limited. To identify stimuli that might prime B cells for enhanced function in vitro, we have compared the effects of anti-Ig with helper T (Th) cells on the formation of B lymphoblasts and the subsequent ability of the blasts to grow and secrete Ig. The B blasts first were induced by either anti-Ig, anti-Ig plus T cell-derived lymphokines, or alloreactive T blasts. Each population of B blasts showed enhanced expression of cell surface adhesion molecules, interleukin 2 receptor (IL-2R) p55, and MHC products, as well as decreased expression of IgD. The allo-activated B blasts were distinctive in expressing low levels of Thy-1 and increased reactivity with peanut agglutinin, a marker of germinal center B blasts in situ. The function of the different populations of B blasts was also different. Whereas anti-Ig or anti-Ig plus lymphokines primed for enhanced responses to lipopolysaccharide (LPS), the B blasts induced by Th cells were insensitive to LPS. B lymphoblasts that had been activated in the presence of helper factors or Th cells responded vigorously to recombinant IL-2 with growth and Ig secretion, and this response was enhanced in the presence of anti-Ig. The B blasts activated directly by Th cells, but not by anti-Ig plus lymphokines, were primed to secrete high levels of IgG1 and IgA. Therefore, the phenotype and function of a B lymphoblast depends upon the manner in which it is primed. When primed by Th cells, IL-2 proves to be the predominant mediator of clonal expansion and antibody secretion.

  20. Myopathy with abnormal mitochondria, transient low electron transport capacity in the respiratory chain, and absence of energy transduction at sites 1 and 2 in vitro.

    PubMed Central

    Trockel, U; Scholte, H R; Toyka, K V; Busch, H F; Luyt-Houwen, I E; Berden, J A

    1986-01-01

    A male adult with exercise-related myalgia and weakness from the age of 17 years, developed contractions after moderate exertion which were electrically silent. Triglyceride loading or prolonged fasting provoked excessive ketosis. His isolated muscle mitochondria had severe blockade of the respiratory chain, particularly of NADH-CoQ reductase. After 1.5 years a second biopsy was performed. The electron transport capacity of the respiratory chain was much improved, but now a lesion was observed in energy transduction of sites 1 and 2 of the respiratory chain. The unexpected abolishment of respiratory chain blockade was paralleled by only mild clinical improvement. PMID:3016196

  1. Treatment with 8-OH-modified adenine (TLR7 ligand)-allergen conjugates decreases T helper type 2-oriented murine airway inflammation

    PubMed Central

    Nencini, Francesca; Pratesi, Sara; Petroni, Giulia; Filì, Lucia; Cardilicchia, Elisa; Casini, Andrea; Occhiato, Ernesto Giovanni; Calosi, Laura; Bani, Daniele; Romagnani, Sergio; Maggi, Enrico; Parronchi, Paola; Vultaggio, Alessandra

    2015-01-01

    A strategy to improve allergen-specific immunotherapy is to employ new adjuvants stably linked to allergens. The study is addressed to evaluate the in vivo and in vitro effects of allergens [natural Dermatophagoides pteronyssinus 2 (nDer p 2) and ovalbumin (OVA)] chemically bound to an 8-OH-modified adenine. Humoral and cellular responses were analysed in allergen-sensitized and challenged mice by using conjugates (Conj) in a therapeutic setting. The in vitro activity of the conjugates on cytokine production induced by bone marrow dendritic cells and the co-culture system was also investigated. The nDer p 2-Conj treatment in nDer p 2-primed and challenged BALB/c mice reduced the numbers of eosinophils in bronchoalveolar lavage fluid and lung, airway allergen-driven interleukin-13 (IL-13) production in lung mononuclear cells and IgE, in comparison with nDer p 2-treated mice. The increase of IgG2a paralleled that of interferon-γ (IFN-γ) and IL-10 in allergen-stimulated spleen cells. Similar effects were elicited by treatment with OVA-Conj in an OVA-driven BALB/c model. The nDer p 2-Conj or OVA-Conj redirected memory T helper type 2 cells towards the production of IL-10 and IFN-γ also in C57BL/6 mice and when subcutaneously administered. Interleukin-10, IL-12 and IL-27 were produced in vitro by Conj-stimulated bone marrow dendritic cells, whereas IL-10 and IFN-γ were up-regulated in co-cultures of CD11c+ and CD4+ T cells from Conj-treated mice stimulated with allergen. Cytofluorometric analysis indicated that the Conj expanded IFN-γ- and IL-10- producing memory T cells. The Conj effects on IL-10−/− and IL-12−/− mice confirmed the role of IL-10 and IFN-γ in inducing a protective and balanced redirection the T helper type 2-mediated airway inflammation. PMID:25930741

  2. Evidence That the [beta] Subunit of Chlamydia trachomatis Ribonucleotide Reductase Is Active with the Manganese Ion of Its Manganese(IV)/Iron(III) Cofactor in Site 1

    SciTech Connect

    Dassama, Laura M.K.; Boal, Amie K.; Krebs, Carsten; Rosenzweig, Amy C.; Bollinger, Jr., J. Martin

    2014-10-02

    The reaction of a class I ribonucleotide reductase (RNR) begins when a cofactor in the {beta} subunit oxidizes a cysteine residue {approx}35 {angstrom} away in the {alpha} subunit, generating a thiyl radical. In the class Ic enzyme from Chlamydia trachomatis (Ct), the cysteine oxidant is the Mn{sup IV} ion of a Mn{sup IV}/Fe{sup III} cluster, which assembles in a reaction between O{sub 2} and the Mn{sup II}/Fe{sup II} complex of {beta}. The heterodinuclear nature of the cofactor raises the question of which site, 1 or 2, contains the Mn{sup IV} ion. Because site 1 is closer to the conserved location of the cysteine-oxidizing tyrosyl radical of class Ia and Ib RNRs, we suggested that the Mn{sup IV} ion most likely resides in this site (i.e., {sup 1}Mn{sup IV}/{sup 2}Fe{sup III}), but a subsequent computational study favored its occupation of site 2 ({sup 1}Fe{sup III}/{sup 2}Mn{sup IV}). In this work, we have sought to resolve the location of the Mn{sup IV} ion in Ct RNR-{beta} by correlating X-ray crystallographic anomalous scattering intensities with catalytic activity for samples of the protein reconstituted in vitro by two different procedures. In samples containing primarily Mn{sup IV}/Fe{sup III} clusters, Mn preferentially occupies site 1, but some anomalous scattering from site 2 is observed, implying that both {sup 1}Mn{sup II}/{sup 2}Fe{sup II} and {sup 1}Fe{sup II}/{sup 2}Mn{sup II} complexes are competent to react with O{sub 2} to produce the corresponding oxidized states. However, with diminished Mn{sup II} loading in the reconstitution, there is no evidence for Mn occupancy of site 2, and the greater activity of these 'low-Mn' samples on a per-Mn basis implies that the {sup 1}Mn{sup IV}/{sup 2}Fe{sup III}-{beta} is at least the more active of the two oxidized forms and may be the only active form.

  3. Teaching Integrity

    ERIC Educational Resources Information Center

    Saunders, Sue; Butts, Jennifer Lease

    2011-01-01

    Integrity is one of those essential yet highly ambiguous concepts. For the purpose of this chapter, integrity is defined as that combination of both attributes and actions that makes entities appear to be whole and ethical, as well as consistent. Like the concepts of leadership or wisdom or community or collaboration, integrity is a key element of…

  4. Site 1 protease is required for proteolytic processing of the glycoproteins of the South American hemorrhagic fever viruses Junin, Machupo, and Guanarito.

    PubMed

    Rojek, Jillian M; Lee, Andrew M; Nguyen, NgocThao; Spiropoulou, Christina F; Kunz, Stefan

    2008-06-01

    The cellular proprotein convertase site 1 protease (S1P) has been implicated in the proteolytic processing of the glycoproteins (GPs) of Old World arenaviruses. Here we report that S1P is also involved in the processing of the GPs of the genetically more-distant South American hemorrhagic fever viruses Guanarito, Machupo, and Junin. Efficient cleavage of Guanarito virus GP, whose protease recognition sites deviate from the reported S1P consensus sequence, indicates a broader specificity of S1P than anticipated. Lack of GP processing of Junin virus dramatically reduced production of infectious virus and prevented cell-to-cell propagation. Infection of S1P-deficient cells resulted in viral persistence over several weeks without the emergence of escape variants able to use other cellular proteases for GP processing.

  5. Inverse correlation of expression of microRNA-140-5p with progression of multiple sclerosis and differentiation of encephalitogenic T helper type 1 cells.

    PubMed

    Guan, Hongbing; Singh, Udai P; Rao, Roshni; Mrelashvili, Davit; Sen, Souvik; Hao, Haiping; Zumbrun, Elizabeth E; Singh, Narendra P; Nagarkatti, Prakash S; Nagarkatti, Mitzi

    2016-04-01

    The role of microRNA in the regulation of encephalitogenic T-cell development is of interest in understanding the pathogenesis of multiple sclerosis (MS). Direct binding of microRNAs to their target mRNAs usually suppresses gene expression and facilitates mRNA degradation. In this study, we observed that the expression of several microRNAs was significantly altered in patients with MS. Interestingly, the expression of miR-140-5p, among other microRNAs, was significantly decreased in the peripheral blood mononuclear cells of patients with MS, and this microRNA may regulate encephalitogenic T helper type 1 (Th1) cell differentiation. The expression level of miR-140-5p was inversely correlated with disease severity with greater reduction in relapsing disease compared with remitting disease. Transfection of synthetic miR-140-5p in peripheral blood mononuclear cells suppressed encephalitogenic Th1 differentiation. Signal transducer and activator of transcription 1 (STAT1) was the functional target of miR-140-5p - transfection of the synthetic miR-140-5p suppressed activation of STAT1 and the expression of its downstream target, T-bet. Our results suggested that miR-140-5p is probably involved in the regulation of encephalitogenic T cells in the pathogenesis of MS. PMID:26780721

  6. A novel lineage transcription factor based analysis reveals differences in T helper cell subpopulation development in infected and intrauterine growth restricted (IUGR) piglets.

    PubMed

    Ebner, F; Rausch, S; Scharek-Tedin, L; Pieper, R; Burwinkel, M; Zentek, J; Hartmann, S

    2014-10-01

    Research in mouse and human clearly identified subsets of T helper (Th) cells based on nuclear expression of specific lineage transcription factors. In swine, however, transcription factor based detection of functional subpopulations of porcine Th cells by flow cytometry is so far limited to regulatory T cells via Foxp3. T-bet and GATA-3 are the transcription factors that regulate commitment to Th1 or Th2 cells, respectively. In this study we prove GATA-3 and T-bet expression in porcine CD4(+) cells polarized in vitro. Importantly, GATA-3 and T-bet expressing cells were detectable in pigs infected with pathogens associated with Th2 and Th1 immune responses. Increased frequencies of GATA-3 positive CD4(+) cells are found in vivo in pigs experimentally infected with the nematode Trichuris suis, whereas porcine reproductive and respiratory syndrome virus (PRRSV) infection elicited T-bet positive CD4(+) T cells. Analysing the immune status of pre-weaning piglets with intrauterine growth restriction (IUGR) we found an increased expression of Foxp3, T-bet and GATA-3 in CD4(+) and CD4(+)CD8(+) double-positive T cells in systemic and intestinal compartments of IUGR piglets. Hence, we established the detection of porcine Th1 and Th2 cells via T-bet and GATA-3 and show that the porcine lineage transcription factors are differentially regulated very early in life depending on the developmental status.

  7. Switches in the mode of transmission select for or against a poorly aphid-transmissible strain of potato virus Y with reduced helper component and virus accumulation.

    PubMed

    Legavre, T; Maia, I G; Casse-Delbart, F; Bernardi, F; Robaglia, C

    1996-07-01

    A poorly aphid-transmissible potato virus Y (PVY-PAT) variant emerged after several cycles of mechanical transmission of an initially aphid-transmissible (AT) isolate. Sequence analysis of the N-terminal region of the helper component-proteinase (HC-Pro) gene revealed a Lys to Glu change at a position previously found to abolish the HC-Pro aphid transmission activity in several potyviruses. Two cycles of aphid transmission allowed the virus population to evolve towards an AT form (PVY-ATnew) where a Glu to Lys change was observed. PVY-PAT produced lower amounts of coat protein and the accumulation of its HC-Pro in infected plants decreased from 7 to 28 days post-inoculation, as compared to PVY-ATnew. RT-PCR and restriction analysis showed that the two virus populations co-existed in the PVY-AT isolate and that the AT form was counter-selected during mechanical transmission. These observations suggest that the Lys to Glu substitution leads to decreased stability of HC-Pro resulting in poor transmissions by aphids, and further strengthen the idea that HC-Pro is involved in the accumulation of potyvirus in infected plants.

  8. CD1d-dependent expansion of NKT follicular helper cells in vivo and in vitro is a product of cellular proliferation and differentiation.

    PubMed

    Rampuria, Pragya; Lang, Mark L

    2015-05-01

    NKT follicular helper cells (NKTfh cells) are a recently discovered functional subset of CD1d-restricted NKT cells. Given the potential for NKTfh cells to promote specific antibody responses and germinal center reactions, there is much interest in determining the conditions under which NKTfh cells proliferate and/or differentiate in vivo and in vitro. We confirm that NKTfh cells expressing the canonical semi-invariant Vα14 TCR were CXCR5(+)/ICOS(+)/PD-1(+)/Bcl6(+) and increased in number following administration of the CD1d-binding glycolipid α-galactosylceramide (α-GC) to C57Bl/6 mice. We show that the α-GC-stimulated increase in NKTfh cells was CD1d-dependent since the effect was diminished by reduced CD1d expression. In vivo and in vitro treatment with α-GC, singly or in combination with IL-2, showed that NKTfh cells increased in number to a greater extent than total NKT cells, but proliferation was near-identical in both populations. Acquisition of the NKTfh phenotype from an adoptively transferred PD-1-depleted cell population was also evident, showing that peripheral NKT cells differentiated into NKTfh cells. Therefore, the α-GC-stimulated, CD1d-dependent increase in peripheral NKTfh cells is a result of cellular proliferation and differentiation. These findings advance our understanding of the immune response following immunization with CD1d-binding glycolipids.

  9. LKB1 inhibition of NF-κB in B cells prevents T follicular helper cell differentiation and germinal center formation

    PubMed Central

    Walsh, Nicole C; Waters, Lynnea R; Fowler, Jessica A; Lin, Mark; Cunningham, Cameron R; Brooks, David G; Rehg, Jerold E; Morse, Herbert C; Teitell, Michael A

    2015-01-01

    T-cell-dependent antigenic stimulation drives the differentiation of B cells into antibody-secreting plasma cells and memory B cells, but how B cells regulate this process is unclear. We show that LKB1 expression in B cells maintains B-cell quiescence and prevents the premature formation of germinal centers (GCs). Lkb1-deficient B cells (BKO) undergo spontaneous B-cell activation and secretion of multiple inflammatory cytokines, which leads to splenomegaly caused by an unexpected expansion of T cells. Within this cytokine response, increased IL-6 production results from heightened activation of NF-κB, which is suppressed by active LKB1. Secreted IL-6 drives T-cell activation and IL-21 production, promoting T follicular helper (TFH) cell differentiation and expansion to support a ∽100-fold increase in steady-state GC B cells. Blockade of IL-6 secretion by BKO B cells inhibits IL-21 expression, a known inducer of TFH-cell differentiation and expansion. Together, these data reveal cell intrinsic and surprising cell extrinsic roles for LKB1 in B cells that control TFH-cell differentiation and GC formation, and place LKB1 as a central regulator of T-cell-dependent humoral immunity. PMID:25916856

  10. A single amino acid position in the helper component of cauliflower mosaic virus can change the spectrum of transmitting vector species.

    PubMed

    Moreno, Aranzazu; Hébrard, Eugénie; Uzest, Marilyne; Blanc, Stéphane; Fereres, Alberto

    2005-11-01

    Viruses frequently use insect vectors to effect rapid spread through host populations. In plant viruses, vector transmission is the major mode of transmission, used by nearly 80% of species described to date. Despite the importance of this phenomenon in epidemiology, the specificity of the virus-vector relationship is poorly understood at both the molecular and the evolutionary level, and very limited data are available on the precise viral protein motifs that control specificity. Here, using the aphid-transmitted Cauliflower mosaic virus (CaMV) as a biological model, we confirm that the "noncirculative" mode of transmission dominant in plant viruses (designated "mechanical vector transmission" in animal viruses) involves extremely specific virus-vector recognition, and we identify an amino acid position in the "helper component" (HC) protein of CaMV involved in such recognition. Site-directed mutagenesis revealed that changing the residue at this position can differentially affect transmission rates obtained with various aphid species, thus modifying the spectrum of vector species for CaMV. Most interestingly, in a virus line transmitted by a single vector species, we observed the rapid appearance of a spontaneous mutant specifically losing its transmissibility by another aphid species. Hence, in addition to the first identification of an HC motif directly involved in specific vector recognition, we demonstrate that change of a virus to a different vector species requires only a single mutation and can occur rapidly and spontaneously.

  11. Transcriptional Response of Human Neurospheres to Helper-Dependent CAV-2 Vectors Involves the Modulation of DNA Damage Response, Microtubule and Centromere Gene Groups

    PubMed Central

    Licursi, Valerio; Brito, Catarina; La Torre, Mattia; Alves, Paula M.; Simao, Daniel; Mottini, Carla; Salinas, Sara; Negri, Rodolfo; Tagliafico, Enrico; Kremer, Eric J.; Saggio, Isabella

    2015-01-01

    Brain gene transfer using viral vectors will likely become a therapeutic option for several disorders. Helper-dependent (HD) canine adenovirus type 2 vectors (CAV-2) are well suited for this goal. These vectors are poorly immunogenic, efficiently transduce neurons, are retrogradely transported to afferent structures in the brain and lead to long-term transgene expression. CAV-2 vectors are being exploited to unravel behavior, cognition, neural networks, axonal transport and therapy for orphan diseases. With the goal of better understanding and characterizing HD-CAV-2 for brain therapy, we analyzed the transcriptomic modulation induced by HD-CAV-2 in human differentiated neurospheres derived from midbrain progenitors. This 3D model system mimics several aspects of the dynamic nature of human brain. We found that differentiated neurospheres are readily transduced by HD-CAV-2 and that transduction generates two main transcriptional responses: a DNA damage response and alteration of centromeric and microtubule probes. Future investigations on the biochemistry of processes highlighted by probe modulations will help defining the implication of HD-CAV-2 and CAR receptor binding in enchaining these functional pathways. We suggest here that the modulation of DNA damage genes is related to viral DNA, while the alteration of centromeric and microtubule probes is possibly enchained by the interaction of the HD-CAV-2 fibre with CAR. PMID:26207738

  12. Gfi1, a transcriptional repressor, inhibits the induction of the T helper type 1 programme in activated CD4 T cells.

    PubMed

    Suzuki, Junpei; Maruyama, Saho; Tamauchi, Hidekazu; Kuwahara, Makoto; Horiuchi, Mika; Mizuki, Masumi; Ochi, Mizuki; Sawasaki, Tatsuya; Zhu, Jinfang; Yasukawa, Masaki; Yamashita, Masakatsu

    2016-04-01

    A transcriptional repressor Gfi1 promotes T helper type 2 (Th2) cell development and inhibits Th17 and inducible regulatory T-cell differentiation. However, the role of Gfi1 in regulating Th1 cell differentiation and the Th1-type immune response remains to be investigated. We herein demonstrate that Gfi1 inhibits the induction of the Th1 programme in activated CD4 T cells. The activated Gfi1-deficient CD4 T cells spontaneously develop into Th1 cells in an interleukin-12- and interferon-γ-independent manner. The increase of Th1-type immune responses was confirmed in vivo in Gfi1-deficient mice using a murine model of nickel allergy and delayed-type hypersensitivity (DTH). The expression levels of Th1-related transcription factors were found to increase in Gfi1-deficient activated CD4 T cells. Tbx21, Eomes and Runx2 were identified as possible direct targets of Gfi1. Gfi1 binds to the Tbx21, Eomes and Runx2 gene loci and reduces the histone H3K4 methylation levels in part by modulating Lsd1 recruitment. Together, these findings demonstrate a novel regulatory role of Gfi1 in the regulation of the Th1-type immune response.

  13. A miR-155-Peli1-c-Rel pathway controls the generation and function of T follicular helper cells.

    PubMed

    Liu, Wen-Hsien; Kang, Seung Goo; Huang, Zhe; Wu, Cheng-Jang; Jin, Hyun Yong; Maine, Christian J; Liu, Yi; Shepherd, Jovan; Sabouri-Ghomi, Mohsen; Gonzalez-Martin, Alicia; Xu, Shunbin; Hoffmann, Alexander; Zheng, Ye; Lu, Li-Fan; Xiao, Nengming; Fu, Guo; Xiao, Changchun

    2016-08-22

    MicroRNA (miRNA) deficiency impairs the generation of T follicular helper (Tfh) cells, but the contribution of individual miRNAs to this phenotype remains poorly understood. In this study, we performed deep sequencing analysis of miRNAs expressed in Tfh cells and identified a five-miRNA signature. Analyses of mutant mice deficient of these miRNAs revealed that miR-22 and miR-183/96/182 are dispensable, but miR-155 is essential for the generation and function of Tfh cells. miR-155 deficiency led to decreased proliferation specifically at the late stage of Tfh cell differentiation and reduced CD40 ligand (CD40L) expression on antigen-specific CD4(+) T cells. Mechanistically, miR-155 repressed the expression of Peli1, a ubiquitin ligase that promotes the degradation of the NF-κB family transcription factor c-Rel, which controls cellular proliferation and CD40L expression. Therefore, our study identifies a novel miR-155-Peli1-c-Rel pathway that specifically regulates Tfh cell generation and function. PMID:27481129

  14. Presentation of high antigen-dose by splenic B220(lo) B cells fosters a feedback loop between T helper type 2 memory and antibody isotype switching.

    PubMed

    Ellis, Jason S; Guloglu, F Betul; Zaghouani, Habib

    2016-04-01

    Effective humoral immunity ensues when antigen presentation by B cells culminates in productive cooperation with T lymphocytes. This collaboration, however, remains ill-defined because naive antigen-specific B cells are rare and difficult to track in vivo. Herein, we used a defined transfer model to examine how B lymphocytes, as antigen-presenting cells, shape the development of T-cell memory suitable for generation of relevant antibody responses. Specifically, we examined how B cells presenting different doses of antigen during the initial priming phase shape the development of CD4 T-cell memory and its influence on humoral immunity. The findings indicate that B cells presenting low dose of antigen favour the development of T helper type 1 (Th1) type memory, while those presenting a high antigen dose yielded better Th2 memory cells. The memory Th2 cells supported the production of antibodies by effector B cells and promoted isotype switching to IgG1. Moreover, among the B-cell subsets tested for induction of Th2 memory, the splenic but not peritoneal B220(lo) cells were most effective in sustaining Th2 memory development as well as immunoglobulin isotype switching, and this function involved a tight control by programmed death 1-programmed death ligand 2 interactions.

  15. Auxofuran, a Novel Metabolite That Stimulates the Growth of Fly Agaric, Is Produced by the Mycorrhiza Helper Bacterium Streptomyces Strain AcH 505†

    PubMed Central

    Riedlinger, Julia; Schrey, Silvia D.; Tarkka, Mika T.; Hampp, Rüdiger; Kapur, Manmohan; Fiedler, Hans-Peter

    2006-01-01

    The mycorrhiza helper bacterium Streptomyces strain AcH 505 improves mycelial growth of ectomycorrhizal fungi and formation of ectomycorrhizas between Amanita muscaria and spruce but suppresses the growth of plant-pathogenic fungi, suggesting that it produces both fungal growth-stimulating and -suppressing compounds. The dominant fungal-growth-promoting substance produced by strain AcH 505, auxofuran, was isolated, and its effect on the levels of gene expression of A. muscaria was investigated. Auxofuran and its synthetic analogue 7-dehydroxy-auxofuran were most effective at a concentration of 15 μM, and application of these compounds led to increased lipid metabolism-related gene expression. Cocultivation of strain AcH 505 and A. muscaria stimulated auxofuran production by the streptomycete. The antifungal substances produced by strain AcH 505 were identified as the antibiotics WS-5995 B and C. WS-5995 B completely blocked mycelial growth at a concentration of 60 μM and caused a cell stress-related gene expression response in A. muscaria. Characterization of these compounds provides the foundation for molecular analysis of the fungus-bacterium interaction in the ectomycorrhizal symbiosis between fly agaric and spruce. PMID:16672502

  16. A shift toward T helper 2 responses and an increase in modulators of innate immunity in depressed patients treated with escitalopram.

    PubMed

    Ho, Pei-Shen; Yeh, Yi-Wei; Huang, San-Yuan; Liang, Chih-Sung

    2015-03-01

    Depression is hypothesized to involve inflammatory processes, and identifying the key cytokines targeted by antidepressant drugs is critical for tailoring treatment to specific cases. However, investigating a limited number of cytokines at one time cannot provide a broad picture of antidepressant-associated immunomodulation. Cytokines act in a network where one could demonstrate pleiotropism, redundancy, synergy, and antagonism with other cytokine functions. This study was aimed at determining whether escitalopram functions as an anti-inflammatory agent and, if so, how it influences cytokine networks. A total of 24 healthy controls and 26 patients with clinical depression requiring inpatient treatment were recruited. A multiplex assay, an efficient tool to simultaneously measure 27 cytokines, was applied in patients with depression before and after 4-week escitalopram treatment. Healthy controls did not take escitalopram and completed cytokine analyses once. We demonstrated that escitalopram increased the levels of interleukin (IL)-1 receptor antagonist and IL-2. Moreover, escitalopram contributed to a shift toward T helper 2 responses and an increase in modulators of innate immunity, leading to a decrease of immune system activation, both innate and adaptive. We suggest that escitalopram modulates the balance of IL-1 and IL-1 receptor antagonist and improves the function and number of T regulatory cells. However, diverse conclusions could be drawn if only a few cytokines were assessed or different significance levels were used. Further studies should investigate a wide range of cytokines in a reliable and valid way, which is key to disentangling the effects of different antidepressants on inflammatory processes.

  17. MyD88-Dependent Silencing of Transgene Expression During the Innate and Adaptive Immune Response to Helper-Dependent Adenovirus

    PubMed Central

    Suzuki, Masataka; Cerullo, Vincenzo; Bertin, Terry K.; Cela, Racel; Clarke, Christian; Guenther, Margaretha; Brunetti-Pierri, Nicola

    2010-01-01

    Abstract Activation of the host innate immune response after systemic administration of adenoviral vectors constitutes a principal impediment to successful clinical gene replacement therapies. Although helper-dependent adenoviruses (HDAds) lack all viral functional genes, systemic administration of a high dose of HDAd still elicits a potent innate immune response in host animals. Toll-like receptors (TLRs) are innate receptors that sense microbial products and trigger the maturation of antigen-presenting cells and cytokine production via MyD88-dependent signaling (except TLR3). Here we show that mice lacking MyD88 exhibit a dramatic reduction in proinflammatory cytokines after intravenous injection of a high dose of HDAd, and show significantly reduced induction of the adaptive immune response when compared with wild-type and TLR2-deficient mice. Importantly, MyD88–/– mice also show significantly higher and longer sustained transgene expression than do wild-type mice. Chromatin immunoprecipitation studies using wild-type and MyD88-deficient primary mouse embryonic fibroblasts showed significant MyD88-dependent transcriptional silencing of the HDAd-encoded transgenes. Our results demonstrate that MyD88 signaling, activated by systemic delivery of HDAd, initiates an innate immune response that suppresses transgene expression at the transcriptional level before initiation of the adaptive immune response. PMID:19824822

  18. Modulation of TNFalpha, a determinant of acute toxicity associated with systemic delivery of first-generation and helper-dependent adenoviral vectors.

    PubMed

    Mane, V P; Toietta, G; McCormack, W M; Conde, I; Clarke, C; Palmer, D; Finegold, M J; Pastore, L; Ng, P; Lopez, J; Lee, B

    2006-09-01

    Understanding the determinants of the host innate immune response to systemic administration of adenoviral (Ad) vectors is critical for clinical gene therapy. Acute toxicity occurs within minutes to hours after vector administration and is characterized by activation of innate immune responses. Our data indicate that in mice, indicators of vector toxicity include elevations of cytokine levels, liver transaminase levels and thrombocytopenia. To discern potential targets for blunting this host response, we evaluated genetic factors in the host response to systemically administered first-generation Ad vectors (FGV) and helper-dependent Ad vectors (HDV) containing beta-galactosidase expression cassettes. A preliminary screen for modulation of vector-induced thrombocytopenia revealed no role for interferon-gamma, mast cells or perforin. However, vector-induced thrombocytopenia and interleukin 6 (IL-6) expression are less evident in tumor necrosis factor alpha (TNFalpha)-deficient mice. Moreover, we also demonstrated that TNFalpha blockade via antibody or huTNFR:Fc pretreatment attenuates both thrombocytopenia (>40% increase in platelet count) and IL-6 expression (>80% reduction) without affecting interleukin 12 , liver enzymes, hematological indices or vector transduction in a murine model. Our data indicate that the use of HDV, in combination with clinically approved TNFalpha immunomodulation, may represent an approach for improving the therapeutic index of Ad gene therapy for human clinical trials. PMID:16708078

  19. Canine Adenovirus Vectors for Lung-Directed Gene Transfer: Efficacy, Immune Response, and Duration of Transgene Expression Using Helper-Dependent Vectors†

    PubMed Central

    Keriel, Anne; René, Céline; Galer, Chad; Zabner, Joseph; Kremer, Eric J.

    2006-01-01

    A major hurdle to the successful clinical use of some viral vectors relates to the innate, adaptive, and memory immune responses that limit the efficiency and duration of transgene expression. Some of these drawbacks may be circumvented by using vectors derived from nonhuman viruses such as canine adenovirus type 2 (CAV-2). Here, we evaluated the potential of CAV-2 vectors for gene transfer to the respiratory tract. We found that CAV-2 transduction was efficient in vivo in the mouse respiratory tract, and ex vivo in well-differentiated human pulmonary epithelia. Notably, the in vivo and ex vivo efficiency was poorly inhibited by sera from mice immunized with a human adenovirus type 5 (HAd5, a ubiquitous human pathogen) vector or by human sera containing HAd5 neutralizing antibodies. Following intranasal instillation in mice, CAV-2 vectors also led to a lower level of inflammatory cytokine secretion and cellular infiltration compared to HAd5 vectors. Moreover, CAV-2 transduction efficiency was increased in vitro in human pulmonary cells and in vivo in the mouse respiratory tract by FK228, a histone deacetylase inhibitor. Finally, by using a helper-dependent CAV-2 vector, we increased the in vivo duration of transgene expression to at least 3 months in immunocompetent mice without immunosuppression. Our data suggest that CAV-2 vectors may be efficient and safe tools for long-term clinical gene transfer to the respiratory tract. PMID:16415025

  20. Conventional and monocyte-derived CD11b(+) dendritic cells initiate and maintain T helper 2 cell-mediated immunity to house dust mite allergen.

    PubMed

    Plantinga, Maud; Guilliams, Martin; Vanheerswynghels, Manon; Deswarte, Kim; Branco-Madeira, Filipe; Toussaint, Wendy; Vanhoutte, Leen; Neyt, Katrijn; Killeen, Nigel; Malissen, Bernard; Hammad, Hamida; Lambrecht, Bart N

    2013-02-21

    Dendritic cells (DCs) are crucial for mounting allergic airway inflammation, but it is unclear which subset of DCs performs this task. By using CD64 and MAR-1 staining, we reliably separated CD11b(+) monocyte-derived DCs (moDCs) from conventional DCs (cDCs) and studied antigen uptake, migration, and presentation assays of lung and lymph node (LN) DCs in response to inhaled house dust mite (HDM). Mainly CD11b(+) cDCs but not CD103(+) cDCs induced T helper 2 (Th2) cell immunity in HDM-specific T cells in vitro and asthma in vivo. Studies in Flt3l(-/-) mice, lacking all cDCs, revealed that moDCs were also sufficient to induce Th2 cell-mediated immunity but only when high-dose HDM was given. The main function of moDCs was the production of proinflammatory chemokines and allergen presentation in the lung during challenge. Thus, we have identified migratory CD11b(+) cDCs as the principal subset inducing Th2 cell-mediated immunity in the LN, whereas moDCs orchestrate allergic inflammation in the lung.

  1. Circulating memory T follicular helper subsets, Tfh2 and Tfh17, participate in the pathogenesis of Guillain-Barré syndrome

    PubMed Central

    Che, Yuanyuan; Qiu, Jinpeng; Jin, Tao; Yin, Fei; Li, Man; Jiang, Yanfang

    2016-01-01

    Circulating memory T follicular helper subsets, Tfh2 and Tfh17 are found to be aberrantly regulated in many autoimmune diseases. However, their roles in the pathogenesis of GBS are still unclear. This study examined the phenotype, distribution, clinical relevance and potential function of Tfh2 and Tfh17 in 36 GBS patients (including 24 AMAN and 12 AIDP patients). We found that the absolute counts of total memory Tfh cells were significantly increased in AMAN, while no significant difference in AIDP compared with HC. Furthermore, the levels of the three subsets of memory Tfh cells, Tfh1, Tfh2 and Tfh17, were differentially altered in AMAN. The absolute counts of Tfh1, Tfh2 and Tfh17 were all increased to a higher level in AMAN. The ratio of (Tfh2+Tfh17)/Tfh1 and the percentages of ICOS+ cells in Tfh2 and Tfh17 cells were greater in AMAN when compared to AIDP and HC, and the former had a positive correlation with the severity of both AMAN and AIDP. Conversely, the percentages of PD1+ cells in Tfh2 and Tfh17 cells were lower in AMAN than in HC. Therefore, circulating memory Tfh2 and Tfh17 cells might promote the autoantibody-related immune response and serve as useful markers to evaluate the progression of AMAN. PMID:26865046

  2. Role of IL-10-producing regulatory B cells in modulating T-helper cell immune responses during silica-induced lung inflammation and fibrosis

    PubMed Central

    Liu, Fangwei; Dai, Wujing; Li, Chao; Lu, Xiaowei; Chen, Ying; Weng, Dong; Chen, Jie

    2016-01-01

    Silicosis is characterized by chronic lung inflammation and fibrosis, which are seriously harmful to human health. Previous research demonstrated that uncontrolled T-helper (Th) cell immune responses were involved in the pathogenesis of silicosis. Lymphocytes also are reported to have important roles. Existing studies on lymphocyte regulation of Th immune responses were limited to T cells, such as the regulatory T (Treg) cell, which could negatively regulate inflammation and promote the process of silicosis. However, other regulatory subsets in silicosis have not been investigated in detail, and the mechanism of immune homeostasis modulation needs further exploration. Another regulatory lymphocyte, the regulatory B cell, has recently drawn increasing attention. In this study, we comprehensively showed the role of IL-10-producing regulatory B cell (B10) in a silicosis model of mice. B10 was inducible by silica instillation. Insufficient B10 amplified inflammation and attenuated lung fibrosis by promoting the Th1 immune response. Insufficient B10 clearly inhibited Treg and decreased the level of IL-10. Our study indicated that B10 could control lung inflammation and exacerbate lung fibrosis by inhibiting Th1 response and modulating the Th balance. The regulatory function of B10 could be associated with Treg induction and IL-10 secretion. PMID:27354007

  3. Inverse correlation of expression of microRNA-140-5p with progression of multiple sclerosis and differentiation of encephalitogenic T helper type 1 cells.

    PubMed

    Guan, Hongbing; Singh, Udai P; Rao, Roshni; Mrelashvili, Davit; Sen, Souvik; Hao, Haiping; Zumbrun, Elizabeth E; Singh, Narendra P; Nagarkatti, Prakash S; Nagarkatti, Mitzi

    2016-04-01

    The role of microRNA in the regulation of encephalitogenic T-cell development is of interest in understanding the pathogenesis of multiple sclerosis (MS). Direct binding of microRNAs to their target mRNAs usually suppresses gene expression and facilitates mRNA degradation. In this study, we observed that the expression of several microRNAs was significantly altered in patients with MS. Interestingly, the expression of miR-140-5p, among other microRNAs, was significantly decreased in the peripheral blood mononuclear cells of patients with MS, and this microRNA may regulate encephalitogenic T helper type 1 (Th1) cell differentiation. The expression level of miR-140-5p was inversely correlated with disease severity with greater reduction in relapsing disease compared with remitting disease. Transfection of synthetic miR-140-5p in peripheral blood mononuclear cells suppressed encephalitogenic Th1 differentiation. Signal transducer and activator of transcription 1 (STAT1) was the functional target of miR-140-5p - transfection of the synthetic miR-140-5p suppressed activation of STAT1 and the expression of its downstream target, T-bet. Our results suggested that miR-140-5p is probably involved in the regulation of encephalitogenic T cells in the pathogenesis of MS.

  4. Pre-employment medical examination of Indonesian domestic helpers in a private clinic in Johor Bahru--an eight year review.

    PubMed

    Leong, C C

    2006-12-01

    On review of 3117 patients' records (all were female Indonesian foreign workers over the span of eight years (1997 to 2004 in a private clinic in Johor Bahru, 223 cases (7.2%) were found to have various medical problems. These 3117 foreigners were to be employed as domestic helpers in Malaysia. They were examined upon arrival in Johor Bahru even though our government did not require this pre-requisite (before 1st August 2005) as they were examined and certified fit in their country of origin before embarking to Malaysia. The proportion of female Indonesian foreign workers who were afflicted with category 1 conditions was 55.6% (which rendered them unfit for employment) and category 2 conditions was 44.4%. The medical problem detected most frequently was hypertension. Sixty-one (80.3%) out of 76 workers had stage 2 hypertension (JNC 7 report). Pulmonary tuberculosis ranked second in this review and is a category 1 condition. This paper supports the recent move by the Malaysian Ministry of Health to implement mandatory medical examinations for all foreign workers arriving in Malaysia within one month of arrival regardless of whether or not they are certified fit in their countries of origin.

  5. Multivalent presentation of MPL by porous silicon microparticles favors T helper 1 polarization enhancing the anti-tumor efficacy of doxorubicin nanoliposomes.

    PubMed

    Meraz, Ismail M; Hearnden, Claire H; Liu, Xuewu; Yang, Marie; Williams, Laura; Savage, David J; Gu, Jianhua; Rhudy, Jessica R; Yokoi, Kenji; Lavelle, Ed C; Serda, Rita E

    2014-01-01

    Porous silicon (pSi) microparticles, in diverse sizes and shapes, can be functionalized to present pathogen-associated molecular patterns that activate dendritic cells. Intraperitoneal injection of MPL-adsorbed pSi microparticles, in contrast to free MPL, resulted in the induction of local inflammation, reflected in the recruitment of neutrophils, eosinophils and proinflammatory monocytes, and the depletion of resident macrophages and mast cells at the injection site. Injection of microparticle-bound MPL resulted in enhanced secretion of the T helper 1 associated cytokines IFN-γ and TNF-α by peritoneal exudate and lymph node cells in response to secondary stimuli while decreasing the anti-inflammatory cytokine IL-10. MPL-pSi microparticles independently exhibited anti-tumor effects and enhanced tumor suppression by low dose doxorubicin nanoliposomes. Intravascular injection of the MPL-bound microparticles increased serum IL-1β levels, which was blocked by the IL-1 receptor antagonist Anakinra. The microparticles also potentiated tumor infiltration by dendritic cells, cytotoxic T lymphocytes, and F4/80+ macrophages, however, a specific reduction was observed in CD204+ macrophages.

  6. Immunomodulation and T Helper TH1/TH2 Response Polarization by CeO2 and TiO2 Nanoparticles

    PubMed Central

    Schanen, Brian C.; Das, Soumen; Reilly, Christopher M.; Warren, William L.; Self, William T.; Seal, Sudipta; Drake, Donald R.

    2013-01-01

    Immunomodulation by nanoparticles, especially as related to the biochemical properties of these unique materials, has scarcely been explored. In an in vitro model of human immunity, we demonstrate two catalytic nanoparticles, TiO2 (oxidant) and CeO2 (antioxidant), have nearly opposite effects on human dendritic cells and T helper (TH) cells. For example, whereas TiO2 nanoparticles potentiated DC maturation that led towards TH1-biased responses, treatment with antioxidant CeO2 nanoparticles induced APCs to secrete the anti-inflammatory cytokine, IL-10, and induce a TH2-dominated T cell profile. In subsequent studies, we demonstrate these results are likely explained by the disparate capacities of the nanoparticles to modulate ROS, since TiO2, but not CeO2 NPs, induced inflammatory responses through an ROS/inflammasome/IL-1β pathway. This novel capacity of metallic NPs to regulate innate and adaptive immunity in profoundly different directions via their ability to modulate dendritic cell function has strong implications for human health since unintentional exposure to these materials is common in modern societies. PMID:23667525

  7. Infusion of Human Bone Marrow-Derived Mesenchymal Stem Cells Alleviates Autoimmune Nephritis in a Lupus Model by Suppressing Follicular Helper T-Cell Development.

    PubMed

    Jang, Eunkyeong; Jeong, Mini; Kim, Sukhyung; Jang, Kiseok; Kang, Bo-Kyeong; Lee, Dong Yun; Bae, Sang-Cheol; Kim, Kyung Suk; Youn, Jeehee

    2016-01-01

    Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the production of autoantibodies to components of the cell nucleus. These autoantibodies are predominantly produced with the help of follicular helper T (Tfh) cells and form immune complexes that trigger widespread inflammatory damage, including nephritis. In recent studies, mesenchymal stem cells (MSCs) elicited diverse, even opposing, effects in experimental and clinical SLE. Here we investigated the effect of human bone marrow-derived MSCs (hBM-MSCs) in a murine model of SLE, the F1 hybrid between New Zealand Black and New Zealand White strains (NZB/W). We found that infusion of female NZB/W mice with hBM-MSCs attenuated glomerulonephritis; it also decreased levels of autoantibodies and the incidence of proteinuria and improved survival. These effects coincided with a decrease in Tfh cells and downstream components. Infiltration of long-lived plasma cells into the inflamed kidney was also reduced in the hBM-MSC-treated mice. Importantly, hBM-MSCs directly suppressed the in vitro differentiation of naive CD4(+) T cells toward Tfh cells in a contact-dependent manner. These results suggest that MSCs attenuate lupus nephritis by suppressing the development of Tfh cells and the subsequent activation of humoral immune components. They thus reveal a novel mechanism by which MSCs regulate humoral autoimmune diseases such as SLE.

  8. CD4 T cell epitope specificity determines follicular versus non-follicular helper differentiation in the polyclonal response to influenza infection or vaccination

    PubMed Central

    Knowlden, Zackery A. G.; Sant, Andrea J.

    2016-01-01

    Follicular helper T cells (Tfh) are essential for B cell production of high-affinity, class-switched antibodies. Much interest in Tfh development focuses on the priming environment of CD4 T cells. Here we explored the role that peptide specificity plays in the partitioning of the polyclonal CD4 T cell repertoire between Tfh and NonTfh lineages during the response to influenza. Surprisingly, we found that CD4 T cells specific for different epitopes exhibited distinct tendencies to segregate into Tfh or NonTfh. To alter the microenvironment and abundance, viral antigens were introduced as purified recombinant proteins in adjuvant as native proteins. Also, the most prototypical epitopes were expressed in a completely foreign protein. In many cases, the epitope-specific response patterns of Tfh vs. NonTfh persisted. The functional TcR avidity of only a subset of epitope-specific cells correlated with the tendency to drive a Tfh response. Thus, we conclude that in a polyclonal CD4 T cell repertoire, features of TcR-peptide:MHC class II complex have a strong deterministic influence on the ability of CD4 T cells to become a Tfh or a NonTfh. Our data is most consistent with at least 2 checkpoints of Tfh selection that include both TcR affinity and B cell presentation. PMID:27329272

  9. Immunisation with a plasmid DNA vaccine encoding gonadotrophin releasing hormone (GnRH-I) and T-helper epitopes in saline suppresses rodent fertility.

    PubMed

    Khan, Mohammad A H; Ogita, Kazuhide; Ferro, Valerie A; Kumasawa, Keiichi; Tsutsui, Tateki; Kimura, Tadashi

    2008-03-01

    Research into active immunisation against gonadotrophin releasing hormone (GnRH-I) has gained widespread acceptance as a means of controlling reproduction and behaviour of farm, companion and wild animals. Many studies describe the use of multiple copies of the self-peptide in linear alignment and conjugation with a large carrier protein to increase the immune response to the peptide. However, problems resulting from carrier protein epitope suppression have seen a diversion of interest into the use of genetic materials to elicit an optimum immune response. In this study, a 533-bp long DNA vaccine was constructed in pcDNAV5-HisB coding for 18.871 kDa GnRH-I-T-helper-V5 epitopes fusion protein. COS1 cells transfected with the vaccine construct were found to release fusion protein into culture supernatant. The vaccine construct (100 microg/mice) in saline solution administered into the anterior quadriceps muscle of ICR male and female mice stimulated antigen-specific IgG antibody responses. Testosterone levels in the vaccinated male mice were significantly (p = 0.021) reduced. A significant reduction in uterine implants were noted following mating between immunised males and control females (p = 0.028), as well as between immunised females and control males (p = 0.004). Histological examination of both the male and female gonads in study week 13 showed atrophy of the seminiferous epithelium and suppression of folliculogenesis. PMID:18262690

  10. MicroRNA-146a regulates ICOS–ICOSL signalling to limit accumulation of T follicular helper cells and germinal centres

    PubMed Central

    Pratama, Alvin; Srivastava, Monika; Williams, Naomi J.; Papa, Ilenia; Lee, Sau K.; Dinh, Xuyen T.; Hutloff, Andreas; Jordan, Margaret A.; Zhao, Jimmy L.; Casellas, Rafael; Athanasopoulos, Vicki; Vinuesa, Carola G.

    2015-01-01

    Tight control of T follicular helper (Tfh) cells is required for optimal maturation of the germinal centre (GC) response. The molecular mechanisms controlling Tfh-cell differentiation remain incompletely understood. Here we show that microRNA-146a (miR-146a) is highly expressed in Tfh cells and peak miR-146a expression marks the decline of the Tfh response after immunization. Loss of miR-146a causes cell-intrinsic accumulation of Tfh and GC B cells. MiR-146a represses several Tfh-cell-expressed messenger RNAs, and of these, ICOS is the most strongly cell autonomously upregulated target in miR-146a-deficient T cells. In addition, miR-146a deficiency leads to increased ICOSL expression on GC B cells and antigen-presenting cells. Partial blockade of ICOS signalling, either by injections of low dose of ICOSL blocking antibody or by halving the gene dose of Icos in miR-146a-deficient T cells, prevents the Tfh and GC B-cell accumulation. Collectively, miR-146a emerges as a post-transcriptional brake to limit Tfh cells and GC responses. PMID:25743066

  11. Clonal analysis of T lymphocytes in the acquired immunodeficiency syndrome. Evidence for an abnormality affecting individual helper and suppressor T cells.

    PubMed Central

    Margolick, J B; Volkman, D J; Lane, H C; Fauci, A S

    1985-01-01

    Purified helper-inducer (T4+) and suppressor-cytotoxic (T8+) lymphocytes from eight patients with acquired immunodeficiency syndrome (AIDS) and eight healthy heterosexual donors were examined by limiting dilution analysis for their ability to be clonally expanded. It was demonstrated that viable T4+ and T8+ lymphocytes from patients with AIDS had markedly reduced proportions of clonable cells compared to the healthy donors (T4 = 1:255 vs. 1:34, P = 0.06; T8 = 1:355 vs. 1:55, P = 0.01). However, the cloned T cells that were obtained from the patients with AIDS demonstrated normal proliferation in response to phytohemagglutinin and alloantigen, and normal ability to help or suppress pokeweed mitogen-driven IgG synthesis. These results strongly suggest that, in addition to a quantitative diminution of T4+ lymphocytes in AIDS, there is an intrinsic functional defect in the surviving T4+ and T8+ lymphocytes, which is reflected by a severe decrease in their potential for clonal expansion. PMID:3161909

  12. Somatic mutations and affinity maturation are impaired by excessive numbers of T follicular helper cells and restored by Treg cells or memory T cells

    PubMed Central

    Preite, Silvia; Baumjohann, Dirk; Foglierini, Mathilde; Basso, Camilla; Ronchi, Francesca; Rodriguez, Blanca M. Fernandez; Corti, Davide; Lanzavecchia, Antonio

    2015-01-01

    We previously reported that Cd3e‐deficient mice adoptively transferred with CD4+ T cells generate high numbers of T follicular helper (Tfh) cells, which go on to induce a strong B‐cell and germinal center (GC) reaction. Here, we show that in this system, GC B cells display an altered distribution between the dark and light zones, and express low levels of activation‐induced cytidine deaminase. Furthermore, GC B cells from Cd3e –/– mice accumulate fewer somatic mutations as compared with GC B cells from wild‐type mice, and exhibit impaired affinity maturation and reduced differentiation into long‐lived plasma cells. Reconstitution of Cd3e –/– mice with regulatory T (Treg) cells restored Tfh‐cell numbers, GC B‐cell numbers and B‐cell distribution within dark and light zones, and the rate of antibody somatic mutations. Tfh‐cell numbers and GC B‐cell numbers and dynamics were also restored by pre‐reconstitution of Cd3e –/– mice with Cxcr5 –/– Treg cells or non‐regulatory, memory CD4+ T cells. Taken together, these findings underline the importance of a quantitatively regulated Tfh‐cell response for an efficient and long‐lasting serological response. PMID:26332258

  13. Fucose-specific DC-SIGN signalling directs T helper cell type-2 responses via IKKε- and CYLD-dependent Bcl3 activation.

    PubMed

    Gringhuis, Sonja I; Kaptein, Tanja M; Wevers, Brigitte A; Mesman, Annelies W; Geijtenbeek, Teunis B H

    2014-05-28

    Carbohydrate-specific signalling through DC-SIGN provides dendritic cells with plasticity to tailor immunity to the nature of invading microbes. Here we demonstrate that recognition of fucose-expressing extracellular pathogens like Schistosoma mansoni and Helicobacter pylori by DC-SIGN favors T helper cell type-2 (TH2) responses via activation of atypical NF-κB family member Bcl3. Crosstalk between TLR and DC-SIGN signalling results in TLR-induced MK2-mediated phosphorylation of LSP1, associated with DC-SIGN, upon fucose binding. Subsequently, IKKε and CYLD are recruited to phosphorylated LSP1. IKKε activation is pivotal for suppression of CYLD deubiquitinase activity and subsequent nuclear translocation of ubiquitinated Bcl3. Bcl3 activation represses TLR-induced proinflammatory cytokine expression, while enhancing interleukin-10 (IL-10) and TH2-attracting chemokine expression, shifting TH differentiation from TH1 to TH2 polarization. Thus, DC-SIGN directs adaptive TH2 immunity to fucose-expressing pathogens via an IKKε-CYLD-dependent signalling pathway leading to Bcl3 activation, which might be targeted in vaccination strategies or to prevent aberrant inflammation and allergy.

  14. High-level eucaryotic in vivo expression of biologically active measles virus hemagglutinin by using an adenovirus type 5 helper-free vector system.

    PubMed Central

    Alkhatib, G; Briedis, D J

    1988-01-01

    The entire measles virus (MV) hemagglutinin (HA)-coding region was reconstructed from cloned cDNAs and used as part of a hybrid transcription unit to replace a region of the adenovirus type 5 genome corresponding to the entire E1a transcription unit and most of the E1b transcription unit. The resulting recombinant virus was stable and able to replicate to high titers in 293 cells (which constitutively express the complementary E1a-E1b functions) in the absence of helper virus. During infection of 293 cells, the hybrid virus expressed MV HA protein which was indistinguishable from that expressed in MV-infected cells in terms of immunoreactivity, gel mobility, glycosylation, subcellular localization, and biologic activity. Infection of 293 cells with the hybrid virus led to high-level synthesis of the MV HA protein (equivalent to 65 to 130% of the level seen in MV-infected cells). At late times after high-multiplicity hybrid virus infection of HeLa and Vero cells (which do not express E1 functions), the level of HA protein synthesis was at least 35% of that seen in 293 cells. This MV-adenovirus recombinant will be useful in the study of the biologic properties of the MV HA protein and in assessment of the potential usefulness of hybrid adenoviruses as live-virus vaccine vectors. Images PMID:3292790

  15. LKB1 inhibition of NF-κB in B cells prevents T follicular helper cell differentiation and germinal center formation.

    PubMed

    Walsh, Nicole C; Waters, Lynnea R; Fowler, Jessica A; Lin, Mark; Cunningham, Cameron R; Brooks, David G; Rehg, Jerold E; Morse, Herbert C; Teitell, Michael A

    2015-06-01

    T-cell-dependent antigenic stimulation drives the differentiation of B cells into antibody-secreting plasma cells and memory B cells, but how B cells regulate this process is unclear. We show that LKB1 expression in B cells maintains B-cell quiescence and prevents the premature formation of germinal centers (GCs). Lkb1-deficient B cells (BKO) undergo spontaneous B-cell activation and secretion of multiple inflammatory cytokines, which leads to splenomegaly caused by an unexpected expansion of T cells. Within this cytokine response, increased IL-6 production results from heightened activation of NF-κB, which is suppressed by active LKB1. Secreted IL-6 drives T-cell activation and IL-21 production, promoting T follicular helper (TFH ) cell differentiation and expansion to support a ~100-fold increase in steady-state GC B cells. Blockade of IL-6 secretion by BKO B cells inhibits IL-21 expression, a known inducer of TFH -cell differentiation and expansion. Together, these data reveal cell intrinsic and surprising cell extrinsic roles for LKB1 in B cells that control TFH -cell differentiation and GC formation, and place LKB1 as a central regulator of T-cell-dependent humoral immunity. PMID:25916856

  16. In situ hybridization to detect and localize signature cytokines of T-helper (Th) 1 and Th2 immune responses in chicken tissues.

    PubMed

    Kidane, Fana Alem; Bilic, Ivana; Mitra, Taniya; Wernsdorf, Patricia; Hess, Michael; Liebhart, Dieter

    2016-07-01

    The avian immune system has been shown to possess a repertoire of cytokines directing T-helper (Th) 1 and Th2 types of immune responses similar to that in mammals. The objective of this study was to establish in situ hybridization (ISH) for the localization of mRNA of selected signal cytokines, chicken interferon-γ (ChIFN-γ), chicken interleukin (ChIL)-4 and ChIL-13 in fixed tissues. RNA probes were generated to hybridize to 488, 318, and 417bp of the respective target mRNA. Probe concentrations ranging from 100ng/ml to 400ng/ml were shown to be suitable to label cells that expressed these cytokines. The specificity of every probe was verified using the respective sense probe. ChIFN-γ, ChIL-4 and ChIL-13 positive cells were observed in the lymphocytic infiltrations of liver and in the periarteriolar lymphatic sheaths of spleen collected from specific-pathogen-free chickens. ISH of these cytokines in a severely inflamed liver due to infiltration with the parasite Histomonas meleagridis revealed the expression of both ChIFN-γ and ChIL-13 mRNA in the mononuclear infiltrates. In conclusion, ChIFN-γ, ChIL-4 and ChIL-13 mRNA were efficiently localized by ISH, which supplies a valid technique to characterize immune responses in fixed tissues. PMID:27269792

  17. T helper cell 2 immune skewing in pregnancy/early life: chemical exposure and the development of atopic disease and allergy.

    PubMed

    McFadden, J P; Thyssen, J P; Basketter, D A; Puangpet, P; Kimber, I

    2015-03-01

    During the last 50 years there has been a significant increase in Western societies of atopic disease and associated allergy. The balance between functional subpopulations of T helper cells (Th) determines the quality of the immune response provoked by antigen. One such subpopulation - Th2 cells - is associated with the production of IgE antibody and atopic allergy, whereas, Th1 cells antagonize IgE responses and the development of allergic disease. In seeking to provide a mechanistic basis for this increased prevalence of allergic disease, one proposal has been the 'hygiene hypothesis', which argues that in Westernized societies reduced exposure during early childhood to pathogenic microorganisms favours the development of atopic allergy. Pregnancy is normally associated with Th2 skewing, which persists for some months in the neonate before Th1/Th2 realignment occurs. In this review, we consider the immunophysiology of Th2 immune skewing during pregnancy. In particular, we explore the possibility that altered and increased patterns of exposure to certain chemicals have served to accentuate this normal Th2 skewing and therefore further promote the persistence of a Th2 bias in neonates. Furthermore, we propose that the more marked Th2 skewing observed in first pregnancy may, at least in part, explain the higher prevalence of atopic disease and allergy in the first born. PMID:25354210

  18. Brucella abortus Omp19 recombinant protein subcutaneously co-delivered with an antigen enhances antigen-specific T helper 1 memory responses and induces protection against parasite challenge.

    PubMed

    Coria, Lorena M; Ibañez, Andrés E; Pasquevich, Karina A; Cobiello, Paula L González; Frank, Fernanda M; Giambartolomei, Guillermo H; Cassataro, Juliana

    2016-01-20

    The discovery of effective adjuvants for many vaccines especially those with limited commercial appeal, such as vaccines to poverty-related diseases, is required. In this work, we demonstrated that subcutaneous co-administration of mice with the outer membrane protein U-Omp19 from Brucella spp. plus OVA as antigen (Ag) increases Ag-specific T cell proliferation and T helper (Th) 1 immune responses in vitro and in vivo. U-Omp19 treated dendritic cells promote IFN-γ production by specific CD4(+) T cells and increases T cell proliferation. U-Omp19 co-administration induces the production of Ag specific effector memory T cell populations (CD4(+) CD44(high) CD62L(low) T cells). Finally, subcutaneous co-administration of U-Omp19 with Trypanosoma cruzi Ags confers protection against virulent parasite challenge, reducing parasitemia and weight loss while increasing mice survival. These results indicate that the bacterial protein U-Omp19 when delivered subcutaneously could be a suitable component of vaccine formulations against infectious diseases requiring Th1 immune responses.

  19. Oral administration of apple condensed tannins delays rheumatoid arthritis development in mice via downregulation of T helper 17 (Th17) cell responses.

    PubMed

    Nakamura, Kosuke; Matsuoka, Hideki; Nakashima, Syohei; Kanda, Tomomasa; Nishimaki-Mogami, Tomoko; Akiyama, Hiroshi

    2015-07-01

    Apples are known to contain high concentrations of phenolic compounds such as condensed tannins. Consumption of condensed tannins has been reported to reduce the risk of many types of chronic diseases including allergies. However, their therapeutic effectiveness and potential in treating autoimmune disease remain controversial. Here, the effect of oral administration of apple condensed tannins (ACT) prepared from apples (Malus pumila cv. Fuji) on bovine type II collagen (CII)-induced arthritis in DBA1/J mice, a well-established murine model of human rheumatoid arthritis (RA), was evaluated. As compared to the control (without ACT administration) group, RA development was delayed and a significant reduction in the RA clinical score was observed in the ACT-administered group. Using cultured splenocytes isolated from CII-immunized mice, ACT-administration was shown to decrease the CII-induced increases in IL-17 expression and production in vitro. We propose that downregulation of T helper (Th) 17 cells is responsible for the ACT-induced RA suppression.

  20. T helper (Th) 1 and Th2 cytokine expression profile in dengue and malaria infection using magnetic bead-based bio-plex assay.

    PubMed

    Maneekan, Pannamas; Leaungwutiwong, Pornsawan; Misse, Dorothee; Luplertlop, Natthanej

    2013-01-01

    Dengue and malaria infections are two very common vector-borne diseases annually affecting millions of people around the world. Both diseases show a variety of clinical presentations, ranging from mild symptoms of dengue fever (DF) to severe dengue hemorrhagic fever (DHF) in dengue infection, and low and high parasitemia in malaria infection. T helper (Th)1 and Th2 cytokine expressions in mild and severe forms of dengue virus type-2 (DENV-2) and Plasmodium falciparum infection, were compared to normal human sera using high throughput magnetic bead-based Bio-Plex assay. A significant elevation of Th1 and Th2 cytokines expression [interleukin (IL)-2, IL-4, IL-5, IL-10, IL-13, granulocyte-macrophage colony-stimulating factor (GM-CSF), interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha] was detected in DENV-2 and P. falciparum malaria infections compared with normal controls (p < 0.05). DENV-2 infection showed a slight higher expression of Th1 and Th2 cytokines in DHF than DF, except for IL-13. In P. falciparum infection, high parasitemia showed a significantly higher expression of IL-4, IL-10, GM-CSF, and TNF-alpha (p < 0.05). Both DENV-2 and P. falciparum malaria infections manifested high IL-10 expression, greatest among the cytokines examined, and in the severe forms of infection. The results of this study should lead to a better understanding of pathogenesis of dengue infection and P. falciparum malaria.