scFv-based “grababody” as a general strategy to improve recruitment of immune effector cells to antibody-targeted tumors

PubMed Central

Cai, Zheng; Fu, Ting; Nagai, Yasuhiro; Lam, Lian; Yee, Marla; Zhu, Zhiqiang; Zhang, Hongtao

2013-01-01

Recruitment of immune cells to tumor cells targeted by a therapeutic antibody can heighten the antitumor efficacy of the antibody. For example, p185her2/neu-targeting antibodies not only downregulate the p185her2/neu kinase (ERBB2) but also trigger complement-dependent cytotoxicity (CDC) and antibody-dependent cellular cytotoxicity (ADCC) through the antibody Fc region. Here we describe a generalized strategy to improve immune cell recruitment to targeted cancer cells, using a modified scFv antibody we call a “grababody” that binds the target protein and endogenous immunoglobulins. The model system we used to illustrate the utility of this platform recognizes p185her2/neu and includes an IgG binding domain. The recombinant scFv grababody that was created recruited circulating human IgGs and attracted immune cells carrying Fc receptors to tumor cells that expressed p185her2/neu. The presence of the IgG binding domain significantly enhanced CDC and ADCC activity and improved anti-tumor activity in vivo. Our results illustrate a novel general approach to improve antibody-like proteins for therapeutic applications. PMID:23396586

(Neuro)transmitter systems in circulating immune cells: a target of immunopharmacological interventions?

PubMed

Tayebati, Seyed Khosrow; Amenta, Francesco

2008-01-01

Increasing evidence indicates the existence of an association between nervous and immune systems. The two systems communicate with each-other to maintain immune homeostasis. Activated immune cells secrete cytokines that influence central nervous system activity. Nervous system, through its peripheral and/or autonomic divisions activates output regulating levels of immune cell activity and the subsequent magnitude of an immune response. On the other hand, neurotransmitters, which represent the main substances involved in nerve cell communications, can influence immune function. Immune organs and circulating immune cells express several (neuro)transmitter systems that can be involved in regulating their activity. The expression of neurotransmitter systems by different subsets of circulating immune cells was reviewed. The regulatory role of different families of (neuro)transmitters (catecholamines, 5-hydroxytryptamine, acetylcholine, histamine and neuropeptides) in modulating levels of immune mediators or specific immune responses is discussed.

Immune Cell Targets of Infection at the Tick-Skin Interface during Powassan Virus Transmission.

PubMed

Hermance, Meghan E; Santos, Rodrigo I; Kelly, Brent C; Valbuena, Gustavo; Thangamani, Saravanan

2016-01-01

Powassan virus (POWV) is a tick-borne flavivirus that can result in a severe neuroinvasive disease with 50% of survivors displaying long-term neurological sequelae. Human POWV cases have been documented in Canada, the United States, and Russia. Although the number of reported POWV human cases has increased in the past fifteen years, POWV remains one of the less studied human pathogenic flaviviruses. Ixodes ticks are the vectors for POWV, and the virus is transmitted to a host's skin very early during the tick feeding process. Central to the successful transmission of a tick-borne pathogen are complex interactions between the host immune response and early tick-mediated immunomodulation, all of which initially occur at the skin interface. In our prior work, we examined the cutaneous immune gene expression during the early stages of POWV-infected Ixodes scapularis feeding. The present study serves to further investigate the skin interface by identifying early cell targets of infection at the POWV-infected tick feeding site. An in vivo infection model consisting of POWV-infected ticks feeding on mice for short durations was used in this study. Skin biopsies from the tick feeding sites were harvested at various early time points, enabling us to examine the skin histopathology and detect POWV viral antigen in immune cells present at the tick feeding site. The histopathology from the present study demonstrates that neutrophil and mononuclear cell infiltrates are recruited earlier to the feeding site of a POWV-infected tick versus an uninfected tick. This is the first report demonstrating that macrophages and fibroblasts contain POWV antigens, which suggests that they are early cellular targets of infection at the tick feeding site. These data provide key insights towards defining the complex interactions between the host immune response and early tick-mediated immunomodulation.

Immune Cell Targets of Infection at the Tick-Skin Interface during Powassan Virus Transmission

PubMed Central

Hermance, Meghan E.; Santos, Rodrigo I.; Kelly, Brent C.; Valbuena, Gustavo; Thangamani, Saravanan

2016-01-01

Powassan virus (POWV) is a tick-borne flavivirus that can result in a severe neuroinvasive disease with 50% of survivors displaying long-term neurological sequelae. Human POWV cases have been documented in Canada, the United States, and Russia. Although the number of reported POWV human cases has increased in the past fifteen years, POWV remains one of the less studied human pathogenic flaviviruses. Ixodes ticks are the vectors for POWV, and the virus is transmitted to a host’s skin very early during the tick feeding process. Central to the successful transmission of a tick-borne pathogen are complex interactions between the host immune response and early tick-mediated immunomodulation, all of which initially occur at the skin interface. In our prior work, we examined the cutaneous immune gene expression during the early stages of POWV-infected Ixodes scapularis feeding. The present study serves to further investigate the skin interface by identifying early cell targets of infection at the POWV-infected tick feeding site. An in vivo infection model consisting of POWV-infected ticks feeding on mice for short durations was used in this study. Skin biopsies from the tick feeding sites were harvested at various early time points, enabling us to examine the skin histopathology and detect POWV viral antigen in immune cells present at the tick feeding site. The histopathology from the present study demonstrates that neutrophil and mononuclear cell infiltrates are recruited earlier to the feeding site of a POWV-infected tick versus an uninfected tick. This is the first report demonstrating that macrophages and fibroblasts contain POWV antigens, which suggests that they are early cellular targets of infection at the tick feeding site. These data provide key insights towards defining the complex interactions between the host immune response and early tick-mediated immunomodulation. PMID:27203436

The innate and adaptive infiltrating immune systems as targets for breast cancer immunotherapy

PubMed Central

Law, Andrew M K; Lim, Elgene; Ormandy, Christopher J

2017-01-01

A cancer cell-centric view has long dominated the field of cancer biology. Research efforts have focussed on aberrant cancer cell signalling pathways and on changes to cancer cell DNA. Mounting evidence demonstrates that many cancer-associated cell types within the tumour stroma co-evolve and support tumour growth and development, greatly modifying cancer cell behaviour, facilitating invasion and metastasis and controlling dormancy and sensitivity to drug therapy. Thus, these stromal cells represent potential targets for cancer therapy. Among these cell types, immune cells have emerged as a promising target for therapy. The adaptive and the innate immune system play an important role in normal mammary development and breast cancer. The number of infiltrating adaptive immune system cells with tumour-rejecting capacity, primarily, T lymphocytes, is lower in breast cancer compared with other cancer types, but infiltration occurs in a large proportion of cases. There is strong evidence demonstrating the importance of the immunosuppressive role of the innate immune system during breast cancer progression. A consideration of components of both the innate and the adaptive immune system is essential for the design and development of immunotherapies in breast cancer. In this review, we focus on the importance of immunosuppressive myeloid-derived suppressor cells (MDSCs) as potential targets for breast cancer therapy. PMID:28193698

The innate and adaptive infiltrating immune systems as targets for breast cancer immunotherapy.

PubMed

Law, Andrew M K; Lim, Elgene; Ormandy, Christopher J; Gallego-Ortega, David

2017-04-01

A cancer cell-centric view has long dominated the field of cancer biology. Research efforts have focussed on aberrant cancer cell signalling pathways and on changes to cancer cell DNA. Mounting evidence demonstrates that many cancer-associated cell types within the tumour stroma co-evolve and support tumour growth and development, greatly modifying cancer cell behaviour, facilitating invasion and metastasis and controlling dormancy and sensitivity to drug therapy. Thus, these stromal cells represent potential targets for cancer therapy. Among these cell types, immune cells have emerged as a promising target for therapy. The adaptive and the innate immune system play an important role in normal mammary development and breast cancer. The number of infiltrating adaptive immune system cells with tumour-rejecting capacity, primarily, T lymphocytes, is lower in breast cancer compared with other cancer types, but infiltration occurs in a large proportion of cases. There is strong evidence demonstrating the importance of the immunosuppressive role of the innate immune system during breast cancer progression. A consideration of components of both the innate and the adaptive immune system is essential for the design and development of immunotherapies in breast cancer. In this review, we focus on the importance of immunosuppressive myeloid-derived suppressor cells (MDSCs) as potential targets for breast cancer therapy. © 2017 The authors.

Active targeted delivery of immune therapeutics to lymph nodes.

PubMed

Bahmani, Baharak; Vohra, Ishaan; Kamaly, Nazila; Abdi, Reza

2018-02-01

Organ transplantation is a life-saving procedure and the only option for patients with end-organ failure. Immune therapeutics have been key to the success of organ transplantation. However, immune therapeutics are still unable to eliminate graft rejection and their toxicity has been implicated in poorer long-term transplant outcomes. Targeted nanodelivery has the potential to enhance not only the therapeutic index but also the bioavailability of the immune therapeutics. One of the key sites of immune therapeutics delivery is lymph node where the priming of immune cells occur. The focus of this review is on nanomedicine research to develop the targeted delivery of immune therapeutics to lymph nodes for controlling immune activation. As nanomedicine creates its niche in clinical care, it provides novel immunotherapy platforms for transplant recipients. Draining lymph nodes are the primary loci of immune activation and represent a formidable site for delivery of wide variety of immune therapeutics. There have been relentless efforts to improve the properties of nanomedicines, to have in-depth knowledge of antigen and drug loading, and, finally, to explore various routes of passive and active targeted delivery to lymph nodes. The application of nanotechnology principles in the delivery of immune therapeutics to the lymph node has created enormous excitement as a paradigm shifting approach that enables targeted delivery of a gamut of molecules to achieve a desired immune response. Therefore, innovative strategies that improve their efficacy while reducing their toxicity are among the highest unmet needs in transplantation.

Colonic Immune Stimulation by Targeted Oral Vaccine

PubMed Central

Kathania, Mahesh; Zadeh, Mojgan; Lightfoot, Yaíma L.; Roman, Robert M.; Sahay, Bikash; Abbott, Jeffrey R.; Mohamadzadeh, Mansour

2013-01-01

Background Currently, sufficient data exist to support the use of lactobacilli as candidates for the development of new oral targeted vaccines. To this end, we have previously shown that Lactobacillus gasseri expressing the protective antigen (PA) component of anthrax toxin genetically fused to a dendritic cell (DC)-binding peptide (DCpep) induced efficacious humoral and T cell-mediated immune responses against Bacillus anthracis Sterne challenge. Methodology/Principal Finding In the present study, we investigated the effects of a dose dependent treatment of mice with L. gasseri expressing the PA-DCpep fusion protein on intestinal and systemic immune responses and confirmed its safety. Treatment of mice with different doses of L. gasseri expressing PA-DCpep stimulated colonic immune responses, resulting in the activation of innate immune cells, including dendritic cells, which induced robust Th1, Th17, CD4+Foxp3+ and CD8+Foxp3+ T cell immune responses. Notably, high doses of L. gasseri expressing PA-DCpep (1012 CFU) were not toxic to the mice. Treatment of mice with L. gasseri expressing PA-DCpep triggered phenotypic maturation and the release of proinflammatory cytokines by dendritic cells and macrophages. Moreover, treatment of mice with L. gasseri expressing PA-DCpep enhanced antibody immune responses, including IgA, IgG1, IgG2b, IgG2c and IgG3. L. gasseri expressing PA-DCpep also increased the gene expression of numerous pattern recognition receptors, including Toll-like receptors, C-type lectin receptors and NOD-like receptors. Conclusion/Significance These findings suggest that L. gasseri expressing PA-DCpep has substantial immunopotentiating properties, as it can induce humoral and T cell-mediated immune responses upon oral administration and may be used as a safe oral vaccine against anthrax challenge. PMID:23383086

Rationale for combination of therapeutic antibodies targeting tumor cells and immune checkpoint receptors: Harnessing innate and adaptive immunity through IgG1 isotype immune effector stimulation.

PubMed

Ferris, Robert L; Lenz, Heinz-Josef; Trotta, Anna Maria; García-Foncillas, Jesús; Schulten, Jeltje; Audhuy, François; Merlano, Marco; Milano, Gerard

2018-02-01

Immunoglobulin (Ig) G1 antibodies stimulate antibody-dependent cell-mediated cytotoxicity (ADCC). Cetuximab, an IgG1 isotype monoclonal antibody, is a standard-of-care treatment for locally advanced and recurrent and/or metastatic squamous cell carcinoma of the head and neck (SCCHN) and metastatic colorectal cancer (CRC). Here we review evidence regarding the clinical relevance of cetuximab-mediated ADCC and other immune functions and provide a biological rationale concerning why this property positions cetuximab as an ideal partner for immune checkpoint inhibitors (ICIs) and other emerging immunotherapies. We performed a nonsystematic review of available preclinical and clinical data involving cetuximab-mediated immune activity and combination approaches of cetuximab with other immunotherapies, including ICIs, in SCCHN and CRC. Indeed, cetuximab mediates ADCC activity in the intratumoral space and primes adaptive and innate cellular immunity. However, counterregulatory mechanisms may lead to immunosuppressive feedback loops. Accordingly, there is a strong rationale for combining ICIs with cetuximab for the treatment of advanced tumors, as targeting CTLA-4, PD-1, and PD-L1 can ostensibly overcome these immunosuppressive counter-mechanisms in the tumor microenvironment. Moreover, combining ICIs (or other immunotherapies) with cetuximab is a promising strategy for boosting immune response and enhancing response rates and durability of response. Cetuximab immune activity-including, but not limited to, ADCC-provides a strong rationale for its combination with ICIs or other immunotherapies to synergistically and fully mobilize the adaptive and innate immunity against tumor cells. Ongoing prospective studies will evaluate the clinical effect of these combination regimens and their immune effect in CRC and SCCHN and in other indications. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Liposomes-coated gold nanocages with antigens and adjuvants targeted delivery to dendritic cells for enhancing antitumor immune response.

PubMed

Liang, Ruijing; Xie, Jun; Li, Jun; Wang, Ke; Liu, Liping; Gao, Yujie; Hussain, Mubashir; Shen, Guanxin; Zhu, Jintao; Tao, Juan

2017-12-01

For nanovaccine-based cancer immunotherapy, dendritic cells (DCs) are one of the most powerful antigen presenting cells (APCs) that initiate and promote the maturation of antigen-specific cytotoxic T lymphocytes (e.g., CD8 + T cells) to induce the local and systemic antitumor immunity and further suppress the tumor metastasis and produce long-term protection against tumor. Thus, the activation and maturation of DCs is the prerequisite for efficient CD8 + T cell-based antitumor immune responses, which is considered as a primary and promising task for nanovaccine engineering. Herein, we introduce a versatile nanovaccine of liposomes-coated gold nanocages (Lipos-AuNCs) modified with DCs specific antibody aCD11c for targeted delivery of adjuvant MPLA and melanoma antigen peptide TRP2 to promote the activation and maturation of DCs, and enhance tumor specific T lymphocytes responses. Moreover, AuNCs accumulation and AuNCs-engulfed DCs migration to regional lymph nodes (RLNs) became real-time visualization through in vivo fluorescence and photoacoustic (PA) imaging to monitor the immunity process. In vivo experimental results demonstrated that the targeted antigen/adjuvants-loaded AuNCs exhibited enhanced antitumor immune response to inhibit tumor growth and metastasis in both B16-F10 prophylactic and lung metastasis models, which may act as a promising nanoplatform for antitumor immunotherapy and in vivo tracking. Copyright © 2017 Elsevier Ltd. All rights reserved.

Novel Adaptive and Innate Immunity Targets in Hypertension

PubMed Central

Abais-Battad, Justine M.; Dasinger, John Henry; Fehrenbach, Daniel J.; Mattson, David L.

2017-01-01

Hypertension is a worldwide epidemic and global health concern as it is a major risk factor for the development of cardiovascular diseases. A relationship between the immune system and its contributing role to the pathogenesis of hypertension has been long established, but substantial advancements within the last few years have dissected specific causal molecular mechanisms. This review will briefly examine these recent studies exploring the involvement of either innate or adaptive immunity pathways. Such pathways to be discussed include innate immunity factors such as antigen presenting cells and pattern recognition receptors, adaptive immune elements including T and B lymphocytes, and more specifically, the emerging role of T regulatory cells, as well as the potential of cytokines and chemokines to serve as signaling messengers connecting innate and adaptive immunity. Together, we summarize these studies to provide new perspective for what will hopefully lead to more targeted approaches to manipulate the immune system as hypertensive therapy. PMID:28336371

NK cells interactions with dendritic cells shape innate and adaptive immunity.

PubMed

Brilot, Fabienne; Strowig, Till; Munz, Christian

2008-05-01

While natural killer (NK) cells received their name from their ability to mediate spontaneous cytotoxicity, it has recently become clear that they require activation to target most transformed and infected cells. Dendritic cells (DCs) have been shown to mediate NK cell activation during innate immune responses. Surprisingly, this interaction was recently reported to be required to restrict infections by NK cells, and to take place in secondary lymphoid organs. Here we review these recent studies on NK cell interactions with DCs, discuss the molecular mechanisms underlying the cross-talk between these two innate lymphocyte populations, and out-line how DCs and NK cells synergize to enhance innate immunity against microbes and tumors as well as shape the adaptive immune system. Based on this better understanding, we propose that NK cells should be targeted for their protective functions and as an adjuvant during immunotherapy development.

DNA vaccines targeting the encoded antigens to dendritic cells induce potent antitumor immunity in mice.

PubMed

Cao, Jun; Jin, Yiqi; Li, Wei; Zhang, Bin; He, Yang; Liu, Hongqiang; Xia, Ning; Wei, Huafeng; Yan, Jian

2013-08-14

Although DNA vaccine holds a great potential for cancer immunotherapy, effective long-lasting antitumoral immunity sufficient to induce durable responses in cancer patients remains to be achieved. Considering the pivotal role of dendritic cells (DC) in the antigen processing and presentation, we prepared DC-targeting DNA vaccines by fusing tumor-associated antigen HER2/neu ectodomain to single chain antibody fragment (scFv) from NLDC-145 antibody specific for DC-restricted surface molecule DEC-205 (scFvNLDC-145), and explored its antitumoral efficacy and underlying mechanisms in mouse breast cancer models. In vivo targeting assay demonstrated that scFvNLDC-145 specifically delivered DNA vaccine-encoded antigen to DC. Compared with untargeted HER2/neu DNA vaccines, vaccination with scFvNLDC-145-HER2/neu markedly promoted the HER2/neu-specific cellular and humoral immune responses with long-lasting immune memory, resulting in effective protection against challenge of HER2/neu-positive D2F2/E2 breast tumor while ineffective in parental HER2/neu-negative D2F2 breast tumor. More importantly, in combination with temporary depletion of regulatory T cells (Treg) by low-dose cyclophosphamide, vaccination with scFvNLDC-145-HER2/neu induced the regression of established D2F2/E2 breast tumor and significantly retarded the development of spontaneous mammary carcinomas in transgenic BALB-neuT mice. Our findings demonstrate that DC-targeted DNA vaccines for in vivo direct delivery of tumor antigens to DC could induce potent antigen-specific cellular and humoral immune responses and, if additional combination with systemic Treg depletion, was able to elicit an impressively therapeutic antitumoral activity, providing a rationale for further development of this approach for cancer treatment.

Tracking targeted bimodal nanovaccines: immune responses and routing in cells, tissue, and whole organism.

PubMed

Cruz, Luis J; Tacken, Paul J; Zeelenberg, Ingrid S; Srinivas, Mangala; Bonetto, Fernando; Weigelin, Bettina; Eich, Christina; de Vries, I Jolanda; Figdor, Carl G

2014-12-01

Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs), involved in the induction of immunity and currently exploited for antitumor immunotherapies. An optimized noninvasive imaging modality capable of determining and quantifying DC-targeted nanoparticle (NP) trajectories could provide valuable information regarding therapeutic vaccine outcome. Here, targeted poly(d,l-lactide-co-glycolide) nanoparticles (PLGA NPs) recognizing DC receptors were equipped with superparamagnetic iron oxide particles (SPIO) or gold nanoparticles with fluorescently labeled antigen. The fluorescent label allowed for rapid analysis and quantification of DC-specific uptake of targeted PLGA NPs in comparison to uptake by other cells. Transmission electron microscopy (TEM) showed that a fraction of the encapsulated antigen reached the lysosomal compartment of DCs, where SPIO and gold were already partially released. However, part of the PLGA NPs localized within the cytoplasm, as confirmed by confocal microscopy. DCs targeted with NPs carrying SPIO or fluorescent antigen were detected within lymph nodes as early as 1 h after injection by magnetic resonance imaging (MRI). Despite the fact that targeting did not markedly affect PLGA NP biodistribution on organism and tissue level, it increased delivery of NPs to DCs residing in peripheral lymph nodes and resulted in enhanced T cell proliferation. In conclusion, two imaging agents within a single carrier allows tracking of targeted PLGA NPs at the subcellular, cellular, and organismal levels, thereby facilitating the rational design of in vivo targeted vaccination strategies.

The evolving roles of memory immune cells in transplantation

PubMed Central

Chen, Wenhao; Ghobrial, Rafik M.; Li, Xian C.

2015-01-01

Memory cells are the products of immune responses but also exert significant impact on subsequent immunity and immune tolerance, thus placing them in a unique position in transplant research. Memory cells are heterogeneous, including not only memory T cells but also memory B cells and innate memory cells. Memory cells are a critical component of protective immunity against invading pathogens, especially in immunosuppressed patients, but they also mediate graft loss and tolerance resistance. Recent studies suggest that some memory cells unexpectedly act as regulatory cells, promoting rather than hindering transplant survival. This functional diversity makes therapeutic targeting of memory cells a challenging task in transplantation. In this article we highlight recent advances in our understanding of memory cells, focusing on diversity of memory cells and mechanisms involved in their induction and functions. We also provide a broad overview on the challenges and opportunities in targeting memory cells in the induction of transplant tolerance. PMID:26102615

Aging of the Immune System. Mechanisms and Therapeutic Targets.

PubMed

Weyand, Cornelia M; Goronzy, Jörg J

2016-12-01

Beginning with the sixth decade of life, the human immune system undergoes dramatic aging-related changes, which continuously progress to a state of immunosenescence. The aging immune system loses the ability to protect against infections and cancer and fails to support appropriate wound healing. Vaccine responses are typically impaired in older individuals. Conversely, inflammatory responses mediated by the innate immune system gain in intensity and duration, rendering older individuals susceptible to tissue-damaging immunity and inflammatory disease. Immune system aging functions as an accelerator for other age-related pathologies. It occurs prematurely in some clinical conditions, most prominently in patients with the autoimmune syndrome rheumatoid arthritis (RA); and such patients serve as an informative model system to study molecular mechanisms of immune aging. T cells from patients with RA are prone to differentiate into proinflammatory effector cells, sustaining chronic-persistent inflammatory lesions in the joints and many other organ systems. RA T cells have several hallmarks of cellular aging; most importantly, they accumulate damaged DNA. Because of deficiency of the DNA repair kinase ataxia telangiectasia mutated, RA T cells carry a higher burden of DNA double-strand breaks, triggering cell-indigenous stress signals that shift the cell's survival potential and differentiation pattern. Immune aging in RA T cells is also associated with metabolic reprogramming; specifically, with reduced glycolytic flux and diminished ATP production. Chronic energy stress affects the longevity and the functional differentiation of older T cells. Altered metabolic patterns provide opportunities to therapeutically target the immune aging process through metabolic interference.

Tumor-targeted IL-2 amplifies T cell-mediated immune response induced by gene therapy with single-chain IL-12

PubMed Central

Lode, Holger N.; Xiang, Rong; Duncan, Steven R.; Theofilopoulos, Argyrios N.; Gillies, Stephen D.; Reisfeld, Ralph A.

1999-01-01

Induction, maintenance, and amplification of tumor-protective immunity after cytokine gene therapy is essential for the clinical success of immunotherapeutic approaches. We investigated whether this could be achieved by single-chain IL-12 (scIL-12) gene therapy followed by tumor-targeted IL-2 using a fusion protein containing a tumor-specific recombinant anti-ganglioside GD2 antibody and IL-2 (ch14.18-IL-2) in a poorly immunogenic murine neuroblastoma model. Herein, we demonstrate the absence of liver and bone marrow metastases after a lethal challenge with NXS2 wild-type cells only in mice (five of six animals) vaccinated with scIL-12-producing NXS2 cells and given a booster injection of low-dose ch14.18-IL-2 fusion protein. This tumor-protective immunity was effective 3 months after initial vaccination, in contrast to control animals treated with a nonspecific fusion protein or an equivalent mixture of antibody and IL-2. Only vaccinated mice receiving the tumor-specific ch14.18-IL-2 fusion protein revealed a reactivation of CD8+ T cells and subsequent MHC class I-restricted tumor target cell lysis in vitro. The sequential increase in the usage of TCR chains Vβ11 and -13 in mouse CD8+ T cells after vaccination and amplification with ch14.18-IL-2 suggests that the initial polyclonal CD8+ T cell response is effectively boosted by targeted IL-2. In conclusion, we demonstrate that a successful boost of a partially protective memory T cell immune response that is induced by scIL-12 gene therapy could be generated by tumor-specific targeting of IL-2 with a ch14.18-IL-2 fusion protein. This approach could increase success rates of clinical cancer vaccine trials. PMID:10411920

Effect of humoral immunity on HIV-1 dynamics with virus-to-target and infected-to-target infections

NASA Astrophysics Data System (ADS)

Elaiw, A. M.; Raezah, A. A.; Alofi, A. S.

2016-08-01

We consider an HIV-1 dynamics model by incorporating (i) two routes of infection via, respectively, binding of a virus to a receptor on the surface of a target cell to start genetic reactions (virus-to-target infection), and the direct transmission from infected cells to uninfected cells through the concept of virological synapse in vivo (infected-to-target infection); (ii) two types of distributed-time delays to describe the time between the virus or infected cell contacts an uninfected CD4+ T cell and the emission of new active viruses; (iii) humoral immune response, where the HIV-1 particles are attacked by the antibodies that are produced from the B lymphocytes. The existence and stability of all steady states are completely established by two bifurcation parameters, R 0 (the basic reproduction number) and R 1 (the viral reproduction number at the chronic-infection steady state without humoral immune response). By constructing Lyapunov functionals and using LaSalle's invariance principle, we have proven that, if R 0 ≤ 1 , then the infection-free steady state is globally asymptotically stable, if R 1 ≤ 1 < R 0 , then the chronic-infection steady state without humoral immune response is globally asymptotically stable, and if R 1 > 1 , then the chronic-infection steady state with humoral immune response is globally asymptotically stable. We have performed numerical simulations to confirm our theoretical results.

Targeted depletion of a MDSC subset unmasks pancreatic ductal adenocarcinoma to adaptive immunity

PubMed Central

Stromnes, Ingunn M.; Brockenbrough, Scott; Izeradjene, Kamel; Carlson, Markus A.; Cuevas, Carlos; Simmons, Randi M.; Greenberg, Philip D.; Hingorani, Sunil R.

2015-01-01

Objective Pancreatic ductal adenocarcinoma (PDA) is characterized by a robust desmoplasia, including the notable accumulation of immunosuppressive cells that shield neoplastic cells from immune detection. Immune evasion may be further enhanced if the malignant cells fail to express high levels of antigens that are sufficiently immunogenic to engender an effector T cell response. In this report, we investigate the predominant subsets of immunosuppressive cancer-conditioned myeloid cells that chronicle and shape pancreas cancer progression. We show that selective depletion of one subset of myeloid-derived suppressor cells (MDSC) in an autochthonous, genetically engineered mouse model (GEMM) of PDA unmasks the ability of the adaptive immune response to engage and target tumor epithelial cells. Methods A combination of in vivo and in vitro studies were performed employing a GEMM that faithfully recapitulates the cardinal features of human PDA. The predominant cancer-conditioned myeloid cell subpopulation was specifically targeted in vivo and the biological outcomes determined. Results PDA orchestrates the induction of distinct subsets of cancer-associated myeloid cells through the production of factors known to influence myelopoeisis. These immature myeloid cells inhibit the proliferation and induce apoptosis of activated T cells. Targeted depletion of granulocytic MDSC (Gr-MDSC) in autochthonous PDA increases the intratumoral accumulation of activated CD8 T cells and apoptosis of tumor epithelial cells, and also remodels the tumor stroma. Conclusions Neoplastic ductal cells of the pancreas induce distinct myeloid cell subsets that promote tumor cell survival and accumulation. Targeted depletion of a single myeloid subset, the Gr-MDSC, can unmask an endogenous T cell response, revealing an unexpected latent immunity and invoking targeting of Gr-MDSC as a potential strategy to exploit for treating this highly lethal disease. PMID:24555999

Modelling a stochastic HIV model with logistic target cell growth and nonlinear immune response function

NASA Astrophysics Data System (ADS)

Wang, Yan; Jiang, Daqing; Alsaedi, Ahmed; Hayat, Tasawar

2018-07-01

A stochastic HIV viral model with both logistic target cell growth and nonlinear immune response function is formulated to investigate the effect of white noise on each population. The existence of the global solution is verified. By employing a novel combination of Lyapunov functions, we obtain the existence of the unique stationary distribution for small white noises. We also derive the extinction of the virus for large white noises. Numerical simulations are performed to highlight the effect of white noises on model dynamic behaviour under the realistic parameters. It is found that the small intensities of white noises can keep the irregular blips of HIV virus and CTL immune response, while the larger ones force the virus infection and immune response to lose efficacy.

Dendritic cell targeted vaccines: Recent progresses and challenges

PubMed Central

Chen, Pengfei; Liu, Xinsheng; Sun, Yuefeng; Zhou, Peng; Wang, Yonglu; Zhang, Yongguang

2016-01-01

ABSTRACT Dendritic cells (DCs) are known to be a set of morphology, structure and function of heterogeneous professional antigen presenting cells (APCs), as well as the strongest functional antigen presenting cells, which can absorb, process and present antigens. As the key regulators of innate and adaptive immune responses, DCs are at the center of the immune system and capable of interacting with both B cells and T cells, thereby manipulating the humoral and cellular immune responses. DCs provide an essential link between the innate and adaptive immunity, and the strong immune activation function of DCs and their properties of natural adjuvants, make them a valuable target for antigen delivery. Targeting antigens to DC-specific endocytic receptors in combination with the relevant antibodies or ligands along with immunostimulatory adjuvants has been recently recognized as a promising strategy for designing an effective vaccine that elicits a strong and durable T cell response against intracellular pathogens and cancer. This opinion article provides a brief summary of the rationales, superiorities and challenges of existing DC-targeting approaches. PMID:26513200

Co-inhibitory immune checkpoints in head and neck squamous cell carcinoma.

PubMed

Deng, W-W; Wu, L; Sun, Z-J

2018-03-01

The upregulation of co-inhibitory immune checkpoints hampers the immune response toward tumor cells and facilitates the tumor cells ability to evade immunosurveillance. Specific inhibitory immune checkpoint delivers inhibitory signals to T cells using multiple mechanisms. More in-depth understanding of the co-inhibitory immune checkpoints could be exploited for head and neck squamous cell carcinoma (HNSCC) treatment. In this review, we summarize the expression and the mechanism of partial co-inhibitory immune checkpoint signals and discuss targeting co-inhibitory immune checkpoints as an immunotherapeutic target for cancer therapy. This review may provide a better understanding of the co-inhibitory immune checkpoints and could promote applications of immunotherapy. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.

Targeting the cytosolic innate immune receptors RIG-I and MDA5 effectively counteracts cancer cell heterogeneity in glioblastoma.

PubMed

Glas, Martin; Coch, Christoph; Trageser, Daniel; Dassler, Juliane; Simon, Matthias; Koch, Philipp; Mertens, Jerome; Quandel, Tamara; Gorris, Raphaela; Reinartz, Roman; Wieland, Anja; Von Lehe, Marec; Pusch, Annette; Roy, Kristin; Schlee, Martin; Neumann, Harald; Fimmers, Rolf; Herrlinger, Ulrich; Brüstle, Oliver; Hartmann, Gunther; Besch, Robert; Scheffler, Björn

2013-06-01

Cellular heterogeneity, for example, the intratumoral coexistence of cancer cells with and without stem cell characteristics, represents a potential root of therapeutic resistance and a significant challenge for modern drug development in glioblastoma (GBM). We propose here that activation of the innate immune system by stimulation of innate immune receptors involved in antiviral and antitumor responses can similarly target different malignant populations of glioma cells. We used short-term expanded patient-specific primary human GBM cells to study the stimulation of the cytosolic nucleic acid receptors melanoma differentiation-associated gene 5 (MDA5) and retinoic acid-inducible gene I (RIG-I). Specifically, we analyzed cells from the tumor core versus "residual GBM cells" derived from the tumor resection margin as well as stem cell-enriched primary cultures versus specimens without stem cell properties. A portfolio of human, nontumor neural cells was used as a control for these studies. The expression of RIG-I and MDA5 could be induced in all of these cells. Receptor stimulation with their respective ligands, p(I:C) and 3pRNA, led to in vitro evidence for an effective activation of the innate immune system. Most intriguingly, all investigated cancer cell populations additionally responded with a pronounced induction of apoptotic signaling cascades revealing a second, direct mechanism of antitumor activity. By contrast, p(I:C) and 3pRNA induced only little toxicity in human nonmalignant neural cells. Granted that the challenge of effective central nervous system (CNS) delivery can be overcome, targeting of RIG-I and MDA5 could thus become a quintessential strategy to encounter heterogeneous cancers in the sophisticated environments of the brain. Copyright © 2013 AlphaMed Press.

Generation of cellular immune memory and B-cell immunity is impaired by natural killer cells.

PubMed

Rydyznski, Carolyn; Daniels, Keith A; Karmele, Erik P; Brooks, Taylor R; Mahl, Sarah E; Moran, Michael T; Li, Caimei; Sutiwisesak, Rujapak; Welsh, Raymond M; Waggoner, Stephen N

2015-02-27

The goal of most vaccines is the induction of long-lived memory T and B cells capable of protecting the host from infection by cytotoxic mechanisms, cytokines and high-affinity antibodies. However, efforts to develop vaccines against major human pathogens such as HIV and HCV have not been successful, thereby highlighting the need for novel approaches to circumvent immunoregulatory mechanisms that limit the induction of protective immunity. Here, we show that mouse natural killer (NK) cells inhibit generation of long-lived virus-specific memory T- and B cells as well as virus-specific antibody production after acute infection. Mechanistically, NK cells suppressed CD4 T cells and follicular helper T cells (T(FH)) in a perforin-dependent manner during the first few days of infection, resulting in a weaker germinal centre (GC) response and diminished immune memory. We anticipate that innovative strategies to relieve NK cell-mediated suppression of immunity should facilitate development of efficacious new vaccines targeting difficult-to-prevent infections.

Immune Cell Metabolism in Systemic Lupus Erythematosus.

PubMed

Choi, Seung-Chul; Titov, Anton A; Sivakumar, Ramya; Li, Wei; Morel, Laurence

2016-11-01

Cellular metabolism represents a newly identified checkpoint of effector functions in the immune system. A solid body of work has characterized the metabolic requirements of normal T cells during activation and differentiation into polarized effector subsets. Similar studies have been initiated to characterize the metabolic requirements for B cells and myeloid cells. Only a few studies though have characterized the metabolism of immune cells in the context of autoimmune diseases. Here, we review what is known on the altered metabolic patterns of CD4 + T cells, B cells, and myeloid cells in lupus patients and lupus-prone mice and how they contribute to lupus pathogenesis. We also discuss how defects in immune metabolism in lupus can be targeted therapeutically.

Targeting the Intratumoral Dendritic Cells by the Oncolytic Adenoviral Vaccine Expressing RANTES Elicits Potent Antitumor Immunity

PubMed Central

Lapteva, Natalia; Aldrich, Melissa; Weksberg, David; Rollins, Lisa; Goltsova, Tatiana; Chen, Si-Yi; Huang, Xue F.

2014-01-01

Summary Dendritic cells (DCs) are professional antigen (Ag)-presenting cells capable of inducing immune responses to tumor Ags and, therefore, play a central role in the induction of antitumor immunity. There is a large amount of evidence, however, about paucity of tumor-associated DCs and that DCs’ immunogenic functions are suppressed in a tumor environment. Here we describe a potent in situ vaccine targeting tumoral DCs in vivo. This vaccine comprised of an oncolytic adenovirus expressing RANTES (regulated upon activation, normally T expressed, and presumably secreted) (Ad-RANTES-E1A), enhanced tumor infiltration, and maturation of Ag-presenting cells in vivo. In this study, we show that intratumoral vaccinations with Ad-RANTES-E1A induced significant primary tumor growth regression and blocked metastasis formation in JC and E.G-7 murine tumor models. This vaccine recruited DCs, macrophages, natural killer cells, and CD8+ T cells to the tumor site, and thus enhanced Ag-specific cytotoxic T lymphocyte responses and natural killer cell responses. DCs purified from the Ad-RANTES-E1A–treated E.G-7 tumors secreted significantly higher levels of interferon-γ and interleukin-12, as compared with control groups and more efficiently enhanced CD8+ T-cell response. This in situ immunization strategy could be a potent antitumor immunotherapy approach for aggressive established tumors. PMID:19238013

Nasal immunization with M cell-targeting ligand-conjugated ApxIIA toxin fragment induces protective immunity against Actinobacillus pleuropneumoniae infection in a murine model.

PubMed

Park, Jisang; Seo, Ki-Weon; Kim, Sae-Hae; Lee, Ha-Yan; Kim, Bumseok; Lim, Chae Woong; Kim, Jin-Hee; Yoo, Han Sang; Jang, Yong-Suk

2015-05-15

Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia and severe economic loss in the swine industry has been caused by the infection. Therefore, the development of an effective vaccine against the bacteria is necessary. ApxII toxin, among several virulence factors expressed by the bacteria, is considered to be a promising vaccine candidate because ApxII toxin not only accompanies cytotoxic and hemolytic activities, but is also expressed in all 15 serotypes of bacteria except serotypes 10 and 14. In this study, we identified the peptide ligand capable of targeting the ligand-conjugated ApxIIA #5 fragment antigen to nasopharynx-associated lymphoid tissue. It was found that nasal immunization with ligand-conjugated ApxIIA #5 induced efficient mucosal and systemic immune responses measured at the levels of antigen-specific antibodies, cytokine-secreting cells after antigen exposure, and antigen-specific lymphocyte proliferation. More importantly, the nasal immunization induced protective immunity against nasal challenge infection of the bacteria, which was confirmed by histopathological studies and bacterial clearance after challenge infection. Collectively, we confirmed that the ligand capable of targeting the ligand-conjugated antigen to nasopharynx-associated lymphoid tissue can be used as an effective nasal vaccine adjuvant to induce protective immunity against A. pleuropneumoniae infection. Copyright © 2015 Elsevier B.V. All rights reserved.

Dendritic cell targeted chitosan nanoparticles for nasal DNA immunization against SARS CoV nucleocapsid protein.

PubMed

Raghuwanshi, Dharmendra; Mishra, Vivek; Das, Dipankar; Kaur, Kamaljit; Suresh, Mavanur R

2012-04-02

This work investigates the formulation and in vivo efficacy of dendritic cell (DC) targeted plasmid DNA loaded biotinylated chitosan nanoparticles for nasal immunization against nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus (SARS-CoV) as antigen. The induction of antigen-specific mucosal and systemic immune response at the site of virus entry is a major challenge for vaccine design. Here, we designed a strategy for noninvasive receptor mediated gene delivery to nasal resident DCs. The pDNA loaded biotinylated chitosan nanoparticles were prepared using a complex coacervation process and characterized for size, shape, surface charge, plasmid DNA loading and protection against nuclease digestion. The pDNA loaded biotinylated chitosan nanoparticles were targeted with bifunctional fusion protein (bfFp) vector for achieving DC selective targeting. The bfFp is a recombinant fusion protein consisting of truncated core-streptavidin fused with anti-DEC-205 single chain antibody (scFv). The core-streptavidin arm of fusion protein binds with biotinylated nanoparticles, while anti-DEC-205 scFv imparts targeting specificity to DC DEC-205 receptor. We demonstrate that intranasal administration of bfFp targeted formulations along with anti-CD40 DC maturation stimuli enhanced magnitude of mucosal IgA as well as systemic IgG against N protein. The strategy led to the detection of augmented levels of N protein specific systemic IgG and nasal IgA antibodies. However, following intranasal delivery of naked pDNA no mucosal and systemic immune responses were detected. A parallel comparison of targeted formulations using intramuscular and intranasal routes showed that the intramuscular route is superior for induction of systemic IgG responses compared with the intranasal route. Our results suggest that targeted pDNA delivery through a noninvasive intranasal route can be a strategy for designing low-dose vaccines.

Immune response to functionalized mesoporous silica nanoparticles for targeted drug delivery

NASA Astrophysics Data System (ADS)

Heidegger, Simon; Gößl, Dorothée; Schmidt, Alexandra; Niedermayer, Stefan; Argyo, Christian; Endres, Stefan; Bein, Thomas; Bourquin, Carole

2015-12-01

Multifunctional mesoporous silica nanoparticles (MSN) have attracted substantial attention with regard to their high potential for targeted drug delivery. For future clinical applications it is crucial to address safety concerns and understand the potential immunotoxicity of these nanoparticles. In this study, we assess the biocompatibility and functionality of multifunctional MSN in freshly isolated, primary murine immune cells. We show that the functionalized silica nanoparticles are rapidly and efficiently taken up into the endosomal compartment by specialized antigen-presenting cells such as dendritic cells. The silica nanoparticles showed a favorable toxicity profile and did not affect the viability of primary immune cells from the spleen in relevant concentrations. Cargo-free MSN induced only very low immune responses in primary cells as determined by surface expression of activation markers and release of pro-inflammatory cytokines such as Interleukin-6, -12 and -1β. In contrast, when surface-functionalized MSN with a pH-responsive polymer capping were loaded with an immune-activating drug, the synthetic Toll-like receptor 7 agonist R848, a strong immune response was provoked. We thus demonstrate that MSN represent an efficient drug delivery vehicle to primary immune cells that is both non-toxic and non-inflammagenic, which is a prerequisite for the use of these particles in biomedical applications.Multifunctional mesoporous silica nanoparticles (MSN) have attracted substantial attention with regard to their high potential for targeted drug delivery. For future clinical applications it is crucial to address safety concerns and understand the potential immunotoxicity of these nanoparticles. In this study, we assess the biocompatibility and functionality of multifunctional MSN in freshly isolated, primary murine immune cells. We show that the functionalized silica nanoparticles are rapidly and efficiently taken up into the endosomal compartment by specialized

Targeting sortilin in immune cells reduces proinflammatory cytokines and atherosclerosis

PubMed Central

Mortensen, Martin B.; Kjolby, Mads; Gunnersen, Stine; Larsen, Jakob V.; Palmfeldt, Johan; Falk, Erling; Nykjaer, Anders; Bentzon, Jacob F.

2014-01-01

Genome-wide association studies have identified a link between genetic variation at the human chromosomal locus 1p13.3 and coronary artery disease. The gene encoding sortilin (SORT1) has been implicated as the causative gene within the locus, as sortilin regulates hepatic lipoprotein metabolism. Here we demonstrated that sortilin also directly affects atherogenesis, independent of its regulatory role in lipoprotein metabolism. In a mouse model of atherosclerosis, deletion of Sort1 did not alter plasma cholesterol levels, but reduced the development of both early and late atherosclerotic lesions. We determined that sortilin is a high-affinity receptor for the proinflammatory cytokines IL-6 and IFN-γ. Moreover, macrophages and Th1 cells (both of which mediate atherosclerotic plaque formation) lacking sortilin had reduced secretion of IL-6 and IFN-γ, but not of other measured cytokines. Transfer of sortilin-deficient BM into irradiated atherosclerotic mice reduced atherosclerosis and systemic markers of inflammation. Together, these data demonstrate that sortilin influences cytokine secretion and that targeting sortilin in immune cells attenuates inflammation and reduces atherosclerosis. PMID:25401472

Targeting innate immunity to downmodulate adaptive immunity and reverse type 1 diabetes

PubMed Central

Itoh, Arata; Ridgway, William M

2017-01-01

Type 1 diabetes (T1D) is characterized by specific destruction of pancreatic insulin-producing beta cells accompanied by evidence of beta-cell-directed autoimmunity such as autoreactive T cells and islet autoantibodies (IAAs). Currently, T1D cannot be prevented or reversed in humans. T1D is easy to prevent in the nonobese diabetic (NOD) spontaneous mouse model but reversing new-onset T1D in mice is more difficult. Since the discovery of the T-cell receptor in the 1980s and the subsequent identification of autoreactive T cells directed toward beta-cell antigens (eg, insulin, glutamic acid decarboxylase), the dream of antigen-specific immunotherapy has dominated the field with its promise of specificity and limited side effects. While such approaches have worked in the NOD mouse, however, dozens of human trials have failed. Broader immunosuppressive approaches (originally cyclosporine, subsequently anti-CD3 antibody) have shown partial successes (e.g., prolonged C peptide preservation) but no major therapeutic efficacy or disease reversal. Human prevention trials have failed, despite the ease of such approaches in the NOD mouse. In the past 50 years, the incidence of T1D has increased dramatically, and one explanation is the “hygiene hypothesis”, which suggests that decreased exposure of the innate immune system to environmental immune stimulants (e.g., bacterial products such as Toll-like receptor (TLR) 4-stimulating lipopolysaccharide [LPS]) dramatically affects the adaptive immune system and increases subsequent autoimmunity. We have tested the role of innate immunity in autoimmune T1D by treating acute-onset T1D in NOD mice with anti-TLR4/MD-2 agonistic antibodies and have shown a high rate of disease reversal. The TLR4 antibodies do not directly stimulate T cells but induce tolerogenic antigen-presenting cells (APCs) that mediate decreased adaptive T-cell responses. Here, we review our current knowledge and suggest future prospects for targeting innate

Designing oral vaccines targeting intestinal dendritic cells.

PubMed

Devriendt, Bert; De Geest, Bruno G; Cox, Eric

2011-04-01

Most pathogens colonize and invade the host at mucosal surfaces, such as the lung and the intestine. To combat intestinal pathogens the induction of local adaptive immune responses is required, which is mainly achieved through oral vaccination. However, most vaccines are ineffective when given orally owing to the hostile environment in the gastrointestinal tract. The encapsulation of antigens in biodegradable microparticulate delivery systems enhances their immunogenicity; however, the uptake of these delivery systems by intestinal immune cells is rather poor. Surface decoration of the particulates with targeting ligands could increase the uptake and mediate the selective targeting of the vaccine to intestinal antigen-presenting cells, including dendritic cells. In this review, current knowledge on dendritic cell subsets is discussed, along with progress in the development of selective antigen targeting to these cells, in addition to focusing on data obtained in mice and, where possible, the pig, as a non-rodent animal model for humans. Moreover, the potential use and benefits of Fcγ receptor-mediated targeting of antigen delivery systems are highlighted. In conclusion, dendritic cell targeting ligands grafted on antigen carrier systems should preferably bind to a conserved endocytotic receptor, facilitating the design of a multispecies vaccine platform, which could elicit robust protective immune responses against enteric pathogens.

Targeting myeloid-derived suppressor cells for cancer immunotherapy.

PubMed

Liu, Yijun; Wei, Guowei; Cheng, Wesley A; Dong, Zhenyuan; Sun, Han; Lee, Vincent Y; Cha, Soung-Chul; Smith, D Lynne; Kwak, Larry W; Qin, Hong

2018-05-31

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells with an immune suppressive phenotype. They represent a critical component of the immune suppressive niche described in cancer, where they support immune escape and tumor progression through direct effects on both the innate and adaptive immune responses, largely by contributing to maintenance of a high oxidative stress environment. The number of MDSCs positively correlates with protumoral activity, and often diminishes the effectiveness of immunotherapies, which is particularly problematic with the emergence of personalized medicine. Approaches targeting MDSCs showed promising results in preclinical studies and are under active investigation in clinical trials in combination with various immune checkpoint inhibitors. In this review, we discuss MDSC targets and therapeutic approaches targeting MDSC that have the aim of enhancing the existing tumor therapies.

Programming Native CRISPR Arrays for the Generation of Targeted Immunity.

PubMed

Hynes, Alexander P; Labrie, Simon J; Moineau, Sylvain

2016-05-03

The adaptive immune system of prokaryotes, called CRISPR-Cas (clustered regularly interspaced short palindromic repeats and CRISPR-associated genes), results in specific cleavage of invading nucleic acid sequences recognized by the cell's "memory" of past encounters. Here, we exploited the properties of native CRISPR-Cas systems to program the natural "memorization" process, efficiently generating immunity not only to a bacteriophage or plasmid but to any specifically chosen DNA sequence. CRISPR-Cas systems have entered the public consciousness as genome editing tools due to their readily programmable nature. In industrial settings, natural CRISPR-Cas immunity is already exploited to generate strains resistant to potentially disruptive viruses. However, the natural process by which bacteria acquire new target specificities (adaptation) is difficult to study and manipulate. The target against which immunity is conferred is selected stochastically. By biasing the immunization process, we offer a means to generate customized immunity, as well as provide a new tool to study adaptation. Copyright © 2016 Hynes et al.

Immuno-Oncology-The Translational Runway for Gene Therapy: Gene Therapeutics to Address Multiple Immune Targets.

PubMed

Weß, Ludger; Schnieders, Frank

2017-12-01

Cancer therapy is once again experiencing a paradigm shift. This shift is based on extensive clinical experience demonstrating that cancer cannot be successfully fought by addressing only single targets or pathways. Even the combination of several neo-antigens in cancer vaccines is not sufficient for successful, lasting tumor eradication. The focus has therefore shifted to the immune system's role in cancer and the striking abilities of cancer cells to manipulate and/or deactivate the immune system. Researchers and pharma companies have started to target the processes and cells known to support immune surveillance and the elimination of tumor cells. Immune processes, however, require novel concepts beyond the traditional "single-target-single drug" paradigm and need parallel targeting of diverse cells and mechanisms. This review gives a perspective on the role of gene therapy technologies in the evolving immuno-oncology space and identifies gene therapy as a major driver in the development and regulation of effective cancer immunotherapy. Present challenges and breakthroughs ranging from chimeric antigen receptor T-cell therapy, gene-modified oncolytic viruses, combination cancer vaccines, to RNA therapeutics are spotlighted. Gene therapy is recognized as the most prominent technology enabling effective immuno-oncology strategies.

Targeting B cells in immune-mediated inflammatory disease: a comprehensive review of mechanisms of action and identification of biomarkers.

PubMed

Dörner, Thomas; Kinnman, Nils; Tak, Paul P

2010-03-01

B cell-depletion therapy, particularly using anti-CD20 treatment, has provided proof of concept that targeting B cells and the humoral response may result in clinical improvements in immune-mediated inflammatory disease. In this review, the mechanisms of action of B cell-targeting drugs are investigated, and potential biomarkers associated with response to treatment in patients with autoimmune diseases are identified. Most available data relate to B cell depletion using anti-CD20 therapy (rituximab) in patients with rheumatoid arthritis (RA). Treatment leads to significant clinical benefit, but apparently fails to deplete long-lived plasma cells, and discontinuation is associated with relapse. Biomarkers commonly used in studies of B cell-targeted therapies include rheumatoid factor, anti-citrullinated peptide antibodies, and immunoglobulin (Ig) levels. More recently, there has been interest in markers such as B cell phenotype analysis, and B lymphocyte stimulator (BLyS)/a proliferation-inducing ligand (APRIL), the latter particularly in studies of the IgG Fc-transmembrane activator and CAML interactor (TACI) fusion protein (atacicept) and anti-BLyS therapy (belimumab). Data from clinical trials of B cell-depleting agents in RA suggest that specific autoantibodies, BLyS, APRIL, and circulating and synovial B lineage cell levels may have potential as biomarkers predictive of response to treatment. Further trials validating these markers against clinical outcomes in RA are required. In patients with systemic lupus erythematosus, Fc receptors and levels of circulating immune cells (including B cells and natural killer cells) may be relevant markers. 2010 Elsevier Inc. All rights reserved.

The innate immune response in fetal lung mesenchymal cells targets VEGFR2 expression and activity.

PubMed

Medal, Rachel M; Im, Amanda M; Yamamoto, Yasutoshi; Lakhdari, Omar; Blackwell, Timothy S; Hoffman, Hal M; Sahoo, Debashis; Prince, Lawrence S

2017-06-01

In preterm infants, soluble inflammatory mediators target lung mesenchymal cells, disrupting airway and alveolar morphogenesis. However, how mesenchymal cells respond directly to microbial stimuli remains poorly characterized. Our objective was to measure the genome-wide innate immune response in fetal lung mesenchymal cells exposed to the bacterial endotoxin lipopolysaccharide (LPS). With the use of Affymetrix MoGene 1.0st arrays, we showed that LPS induced expression of unique innate immune transcripts heavily weighted toward CC and CXC family chemokines. The transcriptional response was different between cells from E11, E15, and E18 mouse lungs. In all cells tested, LPS inhibited expression of a small core group of genes including the VEGF receptor Vegfr2 Although best characterized in vascular endothelial populations, we demonstrated here that fetal mouse lung mesenchymal cells express Vegfr2 and respond to VEGF-A stimulation. In mesenchymal cells, VEGF-A increased cell migration, activated the ERK/AKT pathway, and promoted FOXO3A nuclear exclusion. With the use of an experimental coculture model of epithelial-mesenchymal interactions, we also showed that VEGFR2 inhibition prevented formation of three-dimensional structures. Both LPS and tyrosine kinase inhibition reduced three-dimensional structure formation. Our data suggest a novel mechanism for inflammation-mediated defects in lung development involving reduced VEGF signaling in lung mesenchyme. Copyright © 2017 the American Physiological Society.

Breaking immune tolerance by targeting Foxp3+ regulatory T cells mitigates Alzheimer's disease pathology

PubMed Central

Baruch, Kuti; Rosenzweig, Neta; Kertser, Alexander; Deczkowska, Aleksandra; Sharif, Alaa Mohammad; Spinrad, Amit; Tsitsou-Kampeli, Afroditi; Sarel, Ayelet; Cahalon, Liora; Schwartz, Michal

2015-01-01

Alzheimer's disease (AD) is a neurodegenerative disorder in which chronic neuroinflammation contributes to disease escalation. Nevertheless, while immunosuppressive drugs have repeatedly failed in treating this disease, recruitment of myeloid cells to the CNS was shown to play a reparative role in animal models. Here we show, using the 5XFAD AD mouse model, that transient depletion of Foxp3+ regulatory T cells (Tregs), or pharmacological inhibition of their activity, is followed by amyloid-β plaque clearance, mitigation of the neuroinflammatory response and reversal of cognitive decline. We further show that transient Treg depletion affects the brain's choroid plexus, a selective gateway for immune cell trafficking to the CNS, and is associated with subsequent recruitment of immunoregulatory cells, including monocyte-derived macrophages and Tregs, to cerebral sites of plaque pathology. Our findings suggest targeting Treg-mediated systemic immunosuppression for treating AD. PMID:26284939

B cell function in the immune response to helminths

PubMed Central

Harris, Nicola

2010-01-01

Similar T helper (Th)2-type immune responses are generated against different helminths parasites, but the mechanisms that initiate Th2 immunity, and the specific immune components that mediate protection against these parasites, can vary greatly. B cells are increasingly recognized as important during the Th2-type immune response to helminths, and B cell activation might be a target for effective vaccine development. Antibody production is a function of B cells during helminth infection and understanding how polyclonal and antigen-specific antibodies contribute should provide important insights into how protective immunity develops. In addition, B cells might also contribute to the host response against helminths through antibody-independent functions including, antigen-presentation, as well as regulatory and effector activity. In this review, we examine the role of B cells during Th2-type immune response to these multicellular parasites. PMID:21159556

Immune surveillance properties of human NK cell-derived exosomes.

PubMed

Lugini, Luana; Cecchetti, Serena; Huber, Veronica; Luciani, Francesca; Macchia, Gianfranco; Spadaro, Francesca; Paris, Luisa; Abalsamo, Laura; Colone, Marisa; Molinari, Agnese; Podo, Franca; Rivoltini, Licia; Ramoni, Carlo; Fais, Stefano

2012-09-15

Exosomes are nanovesicles released by normal and tumor cells, which are detectable in cell culture supernatant and human biological fluids, such as plasma. Functions of exosomes released by "normal" cells are not well understood. In fact, several studies have been carried out on exosomes derived from hematopoietic cells, but very little is known about NK cell exosomes, despite the importance of these cells in innate and adaptive immunity. In this paper, we report that resting and activated NK cells, freshly isolated from blood of healthy donors, release exosomes expressing typical protein markers of NK cells and containing killer proteins (i.e., Fas ligand and perforin molecules). These nanovesicles display cytotoxic activity against several tumor cell lines and activated, but not resting, immune cells. We also show that NK-derived exosomes undergo uptake by tumor target cells but not by resting PBMC. Exosomes purified from plasma of healthy donors express NK cell markers, including CD56+ and perforin, and exert cytotoxic activity against different human tumor target cells and activated immune cells as well. The results of this study propose an important role of NK cell-derived exosomes in immune surveillance and homeostasis. Moreover, this study supports the use of exosomes as an almost perfect example of biomimetic nanovesicles possibly useful in future therapeutic approaches against various diseases, including tumors.

Epigenetic programming of T cells impacts immune reconstitution in hematopoietic stem cell transplant recipients.

PubMed

Hardy, Kristine; Smith, Corey; Tu, Wen Juan; McCuaig, Robert; Panikkar, Archana; Dasari, Vijayendra; Wu, Fan; Tey, Siok-Keen; Hill, Geoffrey R; Khanna, Rajiv; Rao, Sudha

2018-03-27

Immune reconstitution following hematopoietic stem cell transplantation (HSCT) is critical in preventing harmful sequelae in recipients with cytomegalovirus (CMV) infection. To understand the molecular mechanisms underlying immune reconstitution kinetics, we profiled the transcriptome-chromatin accessibility landscape of CMV-specific CD8 + T cells from HCST recipients with different immune reconstitution efficiencies. CMV-specific T cells from HSCT recipients with stable antiviral immunity expressed higher levels of interferon/defense response and cell cycle genes in an interconnected network involving PI3KCG , STAT5B , NFAT , RBPJ , and lower HDAC6 , increasing chromatin accessibility at the enhancer regions of immune and T-cell receptor signaling pathway genes. By contrast, the transcriptional and epigenomic signatures of CMV-specific T cells from HSCT recipients with unstable immune reconstitution showed commonalities with T-cell responses in other nonresolving chronic infections. These signatures included higher levels of EGR and KLF factors that, along with lower JARID2 expression, maintained higher accessibility at promoter and CpG-rich regions of genes associated with apoptosis. Furthermore, epigenetic targeting via inhibition of HDAC6 or JARID2 enhanced the transcription of genes associated with differential responses, suggesting that drugs targeting epigenomic modifiers may have therapeutic potential for enhancing immune reconstitution in HSCT recipients. Taken together, these analyses demonstrate that transcription factors and chromatin modulators create different chromatin accessibility landscapes in T cells of HSCT recipients that not only affect immediate gene expression but also differentially prime cells for responses to additional signals. Epigenetic therapy may be a promising strategy to promote immune reconstitution in HSCT recipients. © 2018 by The American Society of Hematology.

Discovering naturally processed antigenic determinants that confer protective T cell immunity

PubMed Central

Gilchuk, Pavlo; Spencer, Charles T.; Conant, Stephanie B.; Hill, Timothy; Gray, Jennifer J.; Niu, Xinnan; Zheng, Mu; Erickson, John J.; Boyd, Kelli L.; McAfee, K. Jill; Oseroff, Carla; Hadrup, Sine R.; Bennink, Jack R.; Hildebrand, William; Edwards, Kathryn M.; Crowe, James E.; Williams, John V.; Buus, Søren; Sette, Alessandro; Schumacher, Ton N.M.; Link, Andrew J.; Joyce, Sebastian

2013-01-01

CD8+ T cells (TCD8) confer protective immunity against many infectious diseases, suggesting that microbial TCD8 determinants are promising vaccine targets. Nevertheless, current T cell antigen identification approaches do not discern which epitopes drive protective immunity during active infection — information that is critical for the rational design of TCD8-targeted vaccines. We employed a proteomics-based approach for large-scale discovery of naturally processed determinants derived from a complex pathogen, vaccinia virus (VACV), that are presented by the most frequent representatives of four major HLA class I supertypes. Immunologic characterization revealed that many previously unidentified VACV determinants were recognized by smallpox-vaccinated human peripheral blood cells in a variegated manner. Many such determinants were recognized by HLA class I–transgenic mouse immune TCD8 too and elicited protective TCD8 immunity against lethal intranasal VACV infection. Notably, efficient processing and stable presentation of immune determinants as well as the availability of naive TCD8 precursors were sufficient to drive a multifunctional, protective TCD8 response. Our approach uses fundamental insights into T cell epitope processing and presentation to define targets of protective TCD8 immunity within human pathogens that have complex proteomes, suggesting that this approach has general applicability in vaccine sciences. PMID:23543059

Discovering naturally processed antigenic determinants that confer protective T cell immunity.

PubMed

Gilchuk, Pavlo; Spencer, Charles T; Conant, Stephanie B; Hill, Timothy; Gray, Jennifer J; Niu, Xinnan; Zheng, Mu; Erickson, John J; Boyd, Kelli L; McAfee, K Jill; Oseroff, Carla; Hadrup, Sine R; Bennink, Jack R; Hildebrand, William; Edwards, Kathryn M; Crowe, James E; Williams, John V; Buus, Søren; Sette, Alessandro; Schumacher, Ton N M; Link, Andrew J; Joyce, Sebastian

2013-05-01

CD8+ T cells (TCD8) confer protective immunity against many infectious diseases, suggesting that microbial TCD8 determinants are promising vaccine targets. Nevertheless, current T cell antigen identification approaches do not discern which epitopes drive protective immunity during active infection - information that is critical for the rational design of TCD8-targeted vaccines. We employed a proteomics-based approach for large-scale discovery of naturally processed determinants derived from a complex pathogen, vaccinia virus (VACV), that are presented by the most frequent representatives of four major HLA class I supertypes. Immunologic characterization revealed that many previously unidentified VACV determinants were recognized by smallpox-vaccinated human peripheral blood cells in a variegated manner. Many such determinants were recognized by HLA class I-transgenic mouse immune TCD8 too and elicited protective TCD8 immunity against lethal intranasal VACV infection. Notably, efficient processing and stable presentation of immune determinants as well as the availability of naive TCD8 precursors were sufficient to drive a multifunctional, protective TCD8 response. Our approach uses fundamental insights into T cell epitope processing and presentation to define targets of protective TCD8 immunity within human pathogens that have complex proteomes, suggesting that this approach has general applicability in vaccine sciences.

Differentiating Immune Cell Targets in Gut-Associated Lymphoid Tissue for HIV Cure.

PubMed

Khan, Shahzada; Telwatte, Sushama; Trapecar, Martin; Yukl, Steven; Sanjabi, Shomyseh

2017-11-01

The single greatest challenge to an HIV cure is the persistence of latently infected cells containing inducible, replication-competent proviral genomes, which constitute only a small fraction of total or infected cells in the body. Although resting CD4 + T cells in the blood are a well-known source of viral rebound, more than 90% of the body's lymphocytes reside elsewhere. Many are in gut tissue, where HIV DNA levels per million CD4 + T cells are considerably higher than in the blood. Despite the significant contribution of gut tissue to viral replication and persistence, little is known about the cell types that support persistence of HIV in the gut; importantly, T cells in the gut have phenotypic, functional, and survival properties that are distinct from T cells in other tissues. The mechanisms by which latency is established and maintained will likely depend on the location and cytokine milieu surrounding the latently infected cells in each compartment. Therefore, successful HIV cure strategies require identification and characterization of the exact cell types that support viral persistence, particularly in the gut. In this review, we describe the seeding of the latent HIV reservoir in the gut mucosa; highlight the evidence for compartmentalization and depletion of T cells; summarize the immunologic consequences of HIV infection within the gut milieu; propose how the damaged gut environment may promote the latent HIV reservoir; and explore several immune cell targets in the gut and their place on the path toward HIV cure.

The immune complex CTA1-DD/IgG adjuvant specifically targets connective tissue mast cells through FcγRIIIA and augments anti-HPV immunity after nasal immunization.

PubMed

Fang, Y; Zhang, T; Lidell, L; Xu, X; Lycke, N; Xiang, Z

2013-11-01

We have previously reported that CTA1-DD/IgG immune complexes augment antibody responses in a mast cell-dependent manner following intranasal (IN) immunizations. However, from a safety perspective, mast cell activation could preclude clinical use. Therefore, we have extended these studies and demonstrate that CTA1-DD/IgG immune complexes administered IN did not trigger an anaphylactic reaction. Importantly, CTA1-DD/IgE immune complexes did not activate mast cells. Interestingly, only connective tissue, but not mucosal, mast cells could be activated by CTA1-DD/IgG immune complexes. This effect was mediated by FcγRIIIA, only expressed on connective tissue mast cells, and found in the nasal submucosa. FcγRIIIA-deficient mice had compromised responses to immunization adjuvanted by CTA1-DD/IgG. Proof-of-concept studies revealed that IN immunized mice with human papillomavirus (HPV) type 16 L1 virus-like particles (VLP) and CTA1-DD/IgG immune complexes demonstrated strong and sustained specific antibody titers in serum and vaginal secretions. From a mast cell perspective, CTA1-DD/IgG immune complexes appear to be safe and effective mucosal adjuvants.

The Human Natural Killer Cell Immune Synapse

NASA Astrophysics Data System (ADS)

Davis, Daniel M.; Chiu, Isaac; Fassett, Marlys; Cohen, George B.; Mandelboim, Ofer; Strominger, Jack L.

1999-12-01

Inhibitory killer Ig-like receptors (KIR) at the surface of natural killer (NK) cells induced clustering of HLA-C at the contacting surface of target cells. In this manner, inhibitory immune synapses were formed as human NK cells surveyed target cells. At target/NK cell synapses, HLA-C/KIR distributed into rings around central patches of intercellular adhesion molecule-1/lymphocyte function-associated antigen-1, the opposite orientation to mature murine T cell-activating synapses. This organization of protein was stable for at least 20 min. Cells could support multiple synapses simultaneously, and clusters of HLA-C moved as NK cells crawled over target cells. Clustering required a divalent metal cation, explaining how metal chelators inhibit KIR function. Surprisingly, however, formation of inhibitory synapses was unaffected by ATP depletion and the cytoskeletal inhibitors, colchicine and cytochalsins B and D. Clearly, supramolecular organization within plasma membranes is critical for NK cell immunosurveillance.

Innate immunity: Bacterial cell-wall muramyl peptide targets the conserved transcription factor YB-1.

PubMed

Laman, A G; Lathe, R; Savinov, G V; Shepelyakovskaya, A O; Boziev, Kh M; Baidakova, L K; Chulin, A N; Brovko, F A; Svirshchevskaya, E V; Kotelevtsev, Y; Eliseeva, I A; Guryanov, S G; Lyabin, D N; Ovchinnikov, L P; Ivanov, V T

2015-07-08

The bacterial cell wall muramyl dipeptides MDP and glucosaminyl-MDP (GMDP) are powerful immunostimulators but their binding target remains controversial. We previously reported expression cloning of GMDP-binding polypeptides and identification of Y-box protein 1 (YB-1) as their sole target. Here we show specific binding of GMDP to recombinant YB-1 protein and subcellular colocalization of YB-1 and GMDP. GMDP binding to YB-1 upregulated gene expression levels of NF-κB2, a mediator of innate immunity. Furthermore, YB-1 knockdown abolished GMDP-induced Nfkb2 expression. GMDP/YB-1 stimulation led to NF-κB2 cleavage, transport of activated NF-κB2 p52 to the nucleus, and upregulation of NF-κB2-dependent chemokine Cxcr4 gene expression. Therefore, our findings identify YB-1 as new target for muramyl peptide signaling. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Genetic targeting of the active transcription factor XBP1s to dendritic cells potentiates vaccine-induced prophylactic and therapeutic antitumor immunity.

PubMed

Tian, Shenghe; Liu, Zuqiang; Donahue, Cara; Falo, Louis D; You, Zhaoyang

2012-02-01

In vivo dendritic cells (DC) targeting is an attractive approach with potential advantages in vaccine efficacy, cost, and availability. Identification of molecular adjuvants to in vivo "modulate " DC to coordinately render improved Th1 and CD8 T cell immunity, and attenuated deleterious Treg effects, is a critical challenge. Here, we report that in vivo genetic targeting of the active transcription factor XBP1s to DC (XBP1s/DC) potentiated vaccine-induced prophylactic and therapeutic antitumor immunity in multiple tumor models. This immunization strategy is based on a genetic vaccine encoding both cytomegalovirus (CMV)-driven vaccine Aghsp70 and DC-specific CD11c-driven XBP1s. The novel targeted vaccine induced durable Th1 and CD8 T cell responses to poorly immunogenic self/tumor antigen (Ag) and attenuated tumor-associated Treg suppressive function. Bone marrow (BM)-derived DC genetically modified to simultaneously overexpress XBP1s and express Aghsp70 upregulated CD40, CD70, CD86, interleukin (IL)-15, IL-15Rα, and CCR7 expression, and increased IL-6, IL-12, and tumor necrosis factor (TNF)-α production in vitro. XBP1s/DC elevated functional DEC205(+)CD8α(+)DC in the draining lymph nodes (DLN). The data suggest a novel role for XBP1s in modulating DC to potentiate tumor vaccine efficacy via overcoming two major obstacles to tumor vaccines (i.e., T cell hyporesponsiveness against poorly immunologic self/tumor Ag and tumor-associated Treg-mediated suppression) and improving DEC205(+)CD8α(+)DC.

Changes in Nutritional Status Impact Immune Cell Metabolism and Function.

PubMed

Alwarawrah, Yazan; Kiernan, Kaitlin; MacIver, Nancie J

2018-01-01

Immune cell function and metabolism are closely linked. Many studies have now clearly demonstrated that alterations in cellular metabolism influence immune cell function and that, conversely, immune cell function determines the cellular metabolic state. Less well understood, however, are the effects of systemic metabolism or whole organism nutritional status on immune cell function and metabolism. Several studies have demonstrated that undernutrition is associated with immunosuppression, which leads to both increased susceptibility to infection and protection against several types of autoimmune disease, whereas overnutrition is associated with low-grade, chronic inflammation that increases the risk of metabolic and cardiovascular disease, promotes autoreactivity, and disrupts protective immunity. Here, we review the effects of nutritional status on immunity and highlight the effects of nutrition on circulating cytokines and immune cell populations in both human studies and mouse models. As T cells are critical members of the immune system, which direct overall immune response, we will focus this review on the influence of systemic nutritional status on T cell metabolism and function. Several cytokines and hormones have been identified which mediate the effects of nutrition on T cell metabolism and function through the expression and action of key regulatory signaling proteins. Understanding how T cells are sensitive to both inadequate and overabundant nutrients may enhance our ability to target immune cell metabolism and alter immunity in both malnutrition and obesity.

New Strategies in Engineering T-cell Receptor Gene-Modified T cells to More Effectively Target Malignancies.

PubMed

Schmitt, Thomas M; Stromnes, Ingunn M; Chapuis, Aude G; Greenberg, Philip D

2015-12-01

The immune system, T cells in particular, have the ability to target and destroy malignant cells. However, antitumor immune responses induced from the endogenous T-cell repertoire are often insufficient for the eradication of established tumors, as illustrated by the failure of cancer vaccination strategies or checkpoint blockade for most tumors. Genetic modification of T cells to express a defined T-cell receptor (TCR) can provide the means to rapidly generate large numbers of tumor-reactive T cells capable of targeting tumor cells in vivo. However, cell-intrinsic factors as well as immunosuppressive factors in the tumor microenvironment can limit the function of such gene-modified T cells. New strategies currently being developed are refining and enhancing this approach, resulting in cellular therapies that more effectively target tumors and that are less susceptible to tumor immune evasion. ©2015 American Association for Cancer Research.

Targeting the immune system in cancer.

PubMed

Chaudhuri, Devyani; Suriano, Robert; Mittelman, Abraham; Tiwari, Raj K

2009-02-01

The concept of cancer immunotherapy provides a fresh perspective as it is not associated with many of the drawbacks of conventional therapies such as chemotherapy, radiotherapy and surgery. When fully activated the immune system has immense potential as is evident from mis-matched transplanted organs undergoing rapid immunological attack and rejection. However, the development of immune strategies for cancer therapy has been associated with challenges of their own. Early attempts at cancer vaccination were carried out in an empirical manner that did not always lead to reproducibility. This led to a search of tumor associated antigens with the belief that specific targeting of these antigens would lead to successful tumor elimination. Active vaccination with TAA peptides or passive vaccination with specific lymphocytes against these TAAs did not however demonstrate encouraging results in clinical trials. This was mainly because of the lack of an activating immune response which is required for continuous stimulation of lymphocytes and also because of the selection of tumor escape variants that did not express the particular TAA. On the positive side, attempts at characterizing TAAs illuminated the molecular changes that attribute a malignant phenotype to cancer cells. Attempts at cytokine therapy were also met with challenges of high systemic toxicity and a lack of specific lymphocyte activation. It was therefore realized that an ideal vaccinating agent should be able to combine the effects of both these therapeutic strategies, i.e., it should be able to induce an innate immune response which can be tailored to a tumor specific adaptive immune response. By this, the immunosuppressive tumor environment can be altered to become immune activating, thus facilitating the infiltration of myeloid and lymphoid cells that can act in concert leading to tumor regression. In this regard, immunotherapeutic approaches such as DNA vaccines, dendritic cell based vaccines, HSP based

γδ T cell and other immune cells crosstalk in cellular immunity.

PubMed

He, Ying; Wu, Kangni; Hu, Yongxian; Sheng, Lixia; Tie, Ruxiu; Wang, Binsheng; Huang, He

2014-01-01

γδ T cells have been recognized as effectors with immunomodulatory functions in cellular immunity. These abilities enable them to interact with other immune cells, thus having the potential for treatment of various immune-mediated diseases with adoptive cell therapy. So far, the interactions between γδ T cell and other immune cells have not been well defined. Here we will discuss the interactivities among them and the perspective on γδ T cells for their use in immunotherapy could be imagined. The understanding of the crosstalk among the immune cells in immunopathology might be beneficial for the clinical application of γδ T cell.

Tricking the balance: NK cells in anti-cancer immunity.

PubMed

Pahl, Jens; Cerwenka, Adelheid

2017-01-01

Natural Killer (NK) cells are classically considered innate immune effector cells involved in the first line of defense against infected and malignant cells. More recently, NK cells have emerged to acquire properties of adaptive immunity in response to certain viral infections such as expansion of specific NK cell subsets and long-lasting virus-specific responses to secondary challenges. NK cells distinguish healthy cells from abnormal cells by measuring the net input of activating and inhibitory signals perceived from target cells through NK cell surface receptors. Acquisition of activating ligands in combination with reduced expression of MHC class I molecules on virus-infected and cancer cells activates NK cell cytotoxicity and release of immunostimulatory cytokines like IFN-γ. In the cancer microenvironment however, NK cells become functionally impaired by inhibitory factors produced by immunosuppressive immune cells and cancer cells. Here we review recent progress on the role of NK cells in cancer immunity. We describe regulatory factors of the tumor microenvironment on NK cell function which determine cancer cell destruction or escape from immune recognition. Finally, recent strategies that focus on exploiting NK cell anti-cancer responses for immunotherapeutic approaches are outlined. Copyright © 2015 Elsevier GmbH. All rights reserved.

MenTORing Immunity: mTOR Signaling in the Development and Function of Tissue-Resident Immune Cells

PubMed Central

Jones, Russell G.; Pearce, Edward J.

2017-01-01

Tissue-resident immune cells must balance survival in peripheral tissues with the capacity to respond rapidly upon infection or tissue damage, and in turn couple these responses with intrinsic metabolic control and conditions in the tissue microenvironment. The serine/threonine kinase mammalian/mechanistic target of rapamycin (mTOR) is a central integrator of extracellular and intracellular growth signals and cellular metabolism and plays important roles in both innate and adaptive immune responses. This review discusses the function of mTOR signaling in the differentiation and function of tissue-resident immune cells, with focus on the role of mTOR as a metabolic sensor and its impact on metabolic regulation in innate and adaptive immune cells. We also discuss the impact of metabolic constraints in tissues on immune homeostasis and disease, and how manipulating mTOR activity with drugs such as rapamycin can modulate immunity in these contexts. PMID:28514674

Enhancing Oral Vaccine Potency by Targeting Intestinal M Cells

PubMed Central

Azizi, Ali; Kumar, Ashok; Diaz-Mitoma, Francisco; Mestecky, Jiri

2010-01-01

The immune system in the gastrointestinal tract plays a crucial role in the control of infection, as it constitutes the first line of defense against mucosal pathogens. The attractive features of oral immunization have led to the exploration of a variety of oral delivery systems. However, none of these oral delivery systems have been applied to existing commercial vaccines. To overcome this, a new generation of oral vaccine delivery systems that target antigens to gut-associated lymphoid tissue is required. One promising approach is to exploit the potential of microfold (M) cells by mimicking the entry of pathogens into these cells. Targeting specific receptors on the apical surface of M cells might enhance the entry of antigens, initiating the immune response and consequently leading to protection against mucosal pathogens. In this article, we briefly review the challenges associated with current oral vaccine delivery systems and discuss strategies that might potentially target mouse and human intestinal M cells. PMID:21085599

TAM receptor tyrosine kinases as emerging targets of innate immune checkpoint blockade for cancer therapy.

PubMed

Akalu, Yemsratch T; Rothlin, Carla V; Ghosh, Sourav

2017-03-01

Cancer immunotherapy utilizing T-cell checkpoint inhibitors has shown tremendous clinical success. Yet, this mode of treatment is effective in only a subset of patients. Unresponsive patients tend to have non-T-cell-inflamed tumors that lack markers associated with the activation of adaptive anti-tumor immune responses. Notably, elimination of cancer cells by T cells is critically dependent on the optimal activity of innate immune cells. Therefore, identifying new targets that regulate innate immune cell function and promote the engagement of adaptive tumoricidal responses is likely to lead to the development of improved therapies against cancer. Here, we review the TAM receptor tyrosine kinases-TYRO3, AXL, and MERTK-as an emerging class of innate immune checkpoints that participate in key steps of anti-tumoral immunity. Namely, TAM-mediated efferocytosis, negative regulation of dendritic cell activity, and dysregulated production of chemokines collectively favor the escape of malignant cells. Hence, disabling TAM signaling may promote engagement of adaptive immunity and complement T-cell checkpoint blockade. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

HER2-Targeted Polyinosine/Polycytosine Therapy Inhibits Tumor Growth and Modulates the Tumor Immune Microenvironment.

PubMed

Zigler, Maya; Shir, Alexei; Joubran, Salim; Sagalov, Anna; Klein, Shoshana; Edinger, Nufar; Lau, Jeffrey; Yu, Shang-Fan; Mizraji, Gabriel; Globerson Levin, Anat; Sliwkowski, Mark X; Levitzki, Alexander

2016-08-01

The development of targeted therapies that affect multiple signaling pathways and stimulate antitumor immunity is greatly needed. About 20% of patients with breast cancer overexpress HER2. Small molecules and antibodies targeting HER2 convey some survival benefits; however, patients with advanced disease succumb to the disease under these treatment regimens, possibly because HER2 is not completely necessary for the survival of the targeted cancer cells. In the present study, we show that a polyinosine/polycytosine (pIC) HER2-homing chemical vector induced the demise of HER2-overexpressing breast cancer cells, including trastuzumab-resistant cells. Targeting pIC to the tumor evoked a number of cell-killing mechanisms, as well as strong bystander effects. These bystander mechanisms included type I IFN induction, immune cell recruitment, and activation. The HER2-targeted pIC strongly inhibited the growth of HER2-overexpressing tumors in immunocompetent mice. The data presented here could open additional avenues in the treatment of HER2-positive breast cancer. Cancer Immunol Res; 4(8); 688-97. ©2016 AACR. ©2016 American Association for Cancer Research.

A platform to screen for C-type lectin receptor-binding carbohydrates and their potential for cell-specific targeting and immune modulation.

PubMed

Maglinao, Maha; Eriksson, Magdalena; Schlegel, Mark K; Zimmermann, Stephanie; Johannssen, Timo; Götze, Sebastian; Seeberger, Peter H; Lepenies, Bernd

2014-02-10

Myeloid C-type lectin receptors (CLRs) in innate immunity represent a superfamily of pattern recognition receptors that recognize carbohydrate structures on pathogens and self-antigens. The primary interaction of an antigen-presenting cell and a pathogen shapes the following immune response. Therefore, the identification of CLR ligands that can either enhance or modulate the immune response is of interest. We have developed a screening platform based on glycan arrays to identify immune modulatory carbohydrate ligands of CLRs. A comprehensive library of CLRs was expressed by fusing the extracellular part of each respective CLR, the part containing the carbohydrate-recognition domain (CRD), to the Fc fragment of human IgG1 molecules. CLR-Fc fusion proteins display the CRD in a dimeric form, are properly glycosylated, and can be detected by a secondary antibody with a conjugated fluorophore. Thus, they are valuable tools for high-throughput screening. We were able to identify novel carbohydrate binders of CLRs using the glycan array technology. These CLR-binding carbohydrates were then covalently attached to the model antigen ovalbumin. The ovalbumin neoglycoconjugates were used in a dendritic cell/T cell co-culture assay to stimulate transgenic T cells in vitro. In addition, mice were immunized with these conjugates to analyze the immune modulatory properties of the CLR ligands in vivo. The CLR ligands induced an increased Th1 cytokine production in vitro and modulated the humoral response in vivo. The platform described here allows for the identification of CLR ligands, as well as the evaluation of each ligand's cell-specific targeting and immune modulatory properties. Copyright © 2013 Elsevier B.V. All rights reserved.

MiRNAs: dynamic regulators of immune cell functions in inflammation and cancer.

PubMed

Hirschberger, Simon; Hinske, Ludwig Christian; Kreth, Simone

2018-09-01

MicroRNAs (miRNAs), small noncoding RNA molecules, have emerged as important regulators of almost all cellular processes. By binding to specific sequence motifs within the 3'- untranslated region of their target mRNAs, they induce either mRNA degradation or translational repression. In the human immune system, potent miRNAs and miRNA-clusters have been discovered, that exert pivotal roles in the regulation of gene expression. By targeting cellular signaling hubs, these so-called immuno-miRs have fundamental regulative impact on both innate and adaptive immune cells in health and disease. Importantly, they also act as mediators of tumor immune escape. Secreted by cancer cells and consecutively taken up by immune cells, immuno-miRs are capable to influence immune functions towards a blunted anti-tumor response, thus shaping a permissive tumor environment. This review provides an overview of immuno-miRs and their functional impact on individual immune cell entities. Further, implications of immuno-miRs in the amelioration of tumor surveillance are discussed. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

Neutrophils are immune cells preferentially targeted by retinoic acid in elderly subjects

PubMed Central

2010-01-01

Background The immune system gradually deteriorates with age and nutritional status is a major factor in immunosenescence. Of the many nutritional factors implicated in age-related immune dysfunction, vitamin A may be a good candidate, since vitamin A concentrations classically decrease during aging whereas it may possess important immunomodulatory properties via its active metabolites, the retinoic acids. This prompted us to investigate the immune response induced by retinoids in adults and elderly healthy subjects. Before and after oral supplementation with 13cis retinoic acid (0.5 mg/kg/day during 28 days), whole blood cells were phenotyped, and functions of peripheral blood mononuclear cells (PBMC) and polymorphonuclear cells (PMN) were investigated by flow cytometry and ELISA tests. Results In both young adults (n = 20, 25 ± 4 years) and older subjects (n = 20, 65 ± 4 years), retinoic acid supplementation had no effect on the distribution of leukocyte subpopulations or on the functions of PBMC (Il-2 and sIl-2R production, membrane expression of CD25). Concerning PMN, retinoic acid induced an increase in both spontaneous migration and cell surface expression of CD11b in the two different age populations, whereas bactericidal activity and phagocytosis remained unchanged. Conclusions We demonstrated that retinoic acid induces the same intensity of immune response between adult and older subjects, and more specifically affects PMN functions, i.e. adhesion and migration, than PBMC functions. PMID:20727130

Targeting nanoparticles to M cells with non-peptidic ligands for oral vaccination.

PubMed

Fievez, Virginie; Plapied, Laurence; des Rieux, Anne; Pourcelle, Vincent; Freichels, Hélène; Wascotte, Valentine; Vanderhaeghen, Marie-Lyse; Jerôme, Christine; Vanderplasschen, Alain; Marchand-Brynaert, Jacqueline; Schneider, Yves-Jacques; Préat, Véronique

2009-09-01

The presence of RGD on nanoparticles allows the targeting of beta1 integrins at the apical surface of human M cells and the enhancement of an immune response after oral immunization. To check the hypothesis that non-peptidic ligands targeting intestinal M cells or APCs would be more efficient for oral immunization than RGD, novel non-peptidic and peptidic analogs (RGD peptidomimitic (RGDp), LDV derivative (LDVd) and LDV peptidomimetic (LDVp)) as well as mannose were grafted on the PEG chain of PCL-PEG and incorporated in PLGA-based nanoparticles. RGD and RGDp significantly increased the transport of nanoparticles across an in vitro model of human M cells as compared to enterocytes. RGD, LDVp, LDVd and mannose enhanced nanoparticle uptake by macrophages in vitro. The intraduodenal immunization with RGDp-, LDVd- or mannose-labeled nanoparticles elicited a higher production of IgG antibodies than the intramuscular injection of free ovalbumin or intraduodenal administration of either non-targeted or RGD-nanoparticles. Targeted formulations were also able to induce a cellular immune response. In conclusion, the in vitro transport of nanoparticles, uptake by macrophages and the immune response were positively influenced by the presence of ligands at the surface of nanoparticles. These targeted-nanoparticles could thus represent a promising delivery system for oral immunization.

Low cost delivery of proteins bioencapsulated in plant cells to human non-immune or immune modulatory cells.

PubMed

Xiao, Yuhong; Kwon, Kwang-Chul; Hoffman, Brad E; Kamesh, Aditya; Jones, Noah T; Herzog, Roland W; Daniell, Henry

2016-02-01

Targeted oral delivery of GFP fused with a GM1 receptor binding protein (CTB) or human cell penetrating peptide (PTD) or dendritic cell peptide (DCpep) was investigated. Presence of GFP(+) intact plant cells between villi of ileum confirm their protection in the digestive system from acids/enzymes. Efficient delivery of GFP to gut-epithelial cells by PTD or CTB and to M cells by all these fusion tags confirm uptake of GFP in the small intestine. PTD fusion delivered GFP more efficiently to most tissues or organs than the other two tags. GFP was efficiently delivered to the liver by all fusion tags, likely through the gut-liver axis. In confocal imaging studies of human cell lines using purified GFP fused with different tags, GFP signal of DCpep-GFP was only detected within dendritic cells. PTD-GFP was only detected within kidney or pancreatic cells but not in immune modulatory cells (macrophages, dendritic, T, B, or mast cells). In contrast, CTB-GFP was detected in all tested cell types, confirming ubiquitous presence of GM1 receptors. Such low-cost oral delivery of protein drugs to sera, immune system or non-immune cells should dramatically lower their cost by elimination of prohibitively expensive fermentation, protein purification cold storage/transportation and increase patient compliance. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Biomarker evaluation of face transplant rejection: association of donor T cells with target cell injury.

PubMed

Lian, Christine Guo; Bueno, Ericka M; Granter, Scott R; Laga, Alvaro C; Saavedra, Arturo P; Lin, William M; Susa, Joseph S; Zhan, Qian; Chandraker, Anil K; Tullius, Stefan G; Pomahac, Bohdan; Murphy, George F

2014-06-01

This series of 113 sequential biopsies of full facial transplants provides findings of potential translational significance as well as biological insights that could prompt reexamination of conventional paradigms of effector pathways in skin allograft rejection. Serial biopsies before, during, and after rejection episodes were evaluated for clinicopathological assessment that in selected cases included specific biomarkers for donor-versus-recipient T cells. Histologic evidence of rejection included lymphocyte-associated injury to epidermal rete ridges, follicular infundibula, and dermal microvessels. Surprisingly, during active rejection, immune cells spatially associated with target cell injury consisted abundantly or predominantly of lymphocytes of donor origin with an immunophenotype typical of the resident memory T-cell subset. Current dogma assumes that skin allograft rejection is mediated by recipient T cells that attack epidermal targets, and the association of donor T cells with sites of target cell injury raises questions regarding the potential complexity of immune cell interactions in the rejection process. A more histopathologically refined and immune-based biomarker approach to assessment of rejection of facial transplants is now indicated.

Human Immunodeficiency Virus Immune Cell Receptors, Coreceptors, and Cofactors: Implications for Prevention and Treatment.

PubMed

Woodham, Andrew W; Skeate, Joseph G; Sanna, Adriana M; Taylor, Julia R; Da Silva, Diane M; Cannon, Paula M; Kast, W Martin

2016-07-01

In the last three decades, extensive research on human immunodeficiency virus (HIV) has highlighted its capability to exploit a variety of strategies to enter and infect immune cells. Although CD4(+) T cells are well known as the major HIV target, with infection occurring through the canonical combination of the cluster of differentiation 4 (CD4) receptor and either the C-C chemokine receptor type 5 (CCR5) or C-X-C chemokine receptor type 4 (CXCR4) coreceptors, HIV has also been found to enter other important immune cell types such as macrophages, dendritic cells, Langerhans cells, B cells, and granulocytes. Interestingly, the expression of distinct cellular cofactors partially regulates the rate in which HIV infects each distinct cell type. Furthermore, HIV can benefit from the acquisition of new proteins incorporated into its envelope during budding events. While several publications have investigated details of how HIV manipulates particular cell types or subtypes, an up-to-date comprehensive review on HIV tropism for different immune cells is lacking. Therefore, this review is meant to focus on the different receptors, coreceptors, and cofactors that HIV exploits to enter particular immune cells. Additionally, prophylactic approaches that have targeted particular molecules associated with HIV entry and infection of different immune cells will be discussed. Unveiling the underlying cellular receptors and cofactors that lead to HIV preference for specific immune cell populations is crucial in identifying novel preventative/therapeutic targets for comprehensive strategies to eliminate viral infection.

Human Immunodeficiency Virus Immune Cell Receptors, Coreceptors, and Cofactors: Implications for Prevention and Treatment

PubMed Central

Woodham, Andrew W.; Skeate, Joseph G.; Sanna, Adriana M.; Taylor, Julia R.; Da Silva, Diane M.; Cannon, Paula M.

2016-01-01

Abstract In the last three decades, extensive research on human immunodeficiency virus (HIV) has highlighted its capability to exploit a variety of strategies to enter and infect immune cells. Although CD4+ T cells are well known as the major HIV target, with infection occurring through the canonical combination of the cluster of differentiation 4 (CD4) receptor and either the C-C chemokine receptor type 5 (CCR5) or C-X-C chemokine receptor type 4 (CXCR4) coreceptors, HIV has also been found to enter other important immune cell types such as macrophages, dendritic cells, Langerhans cells, B cells, and granulocytes. Interestingly, the expression of distinct cellular cofactors partially regulates the rate in which HIV infects each distinct cell type. Furthermore, HIV can benefit from the acquisition of new proteins incorporated into its envelope during budding events. While several publications have investigated details of how HIV manipulates particular cell types or subtypes, an up-to-date comprehensive review on HIV tropism for different immune cells is lacking. Therefore, this review is meant to focus on the different receptors, coreceptors, and cofactors that HIV exploits to enter particular immune cells. Additionally, prophylactic approaches that have targeted particular molecules associated with HIV entry and infection of different immune cells will be discussed. Unveiling the underlying cellular receptors and cofactors that lead to HIV preference for specific immune cell populations is crucial in identifying novel preventative/therapeutic targets for comprehensive strategies to eliminate viral infection. PMID:27410493

MenTORing Immunity: mTOR Signaling in the Development and Function of Tissue-Resident Immune Cells.

PubMed

Jones, Russell G; Pearce, Edward J

2017-05-16

Tissue-resident immune cells must balance survival in peripheral tissues with the capacity to respond rapidly upon infection or tissue damage, and in turn couple these responses with intrinsic metabolic control and conditions in the tissue microenvironment. The serine/threonine kinase mammalian/mechanistic target of rapamycin (mTOR) is a central integrator of extracellular and intracellular growth signals and cellular metabolism and plays important roles in both innate and adaptive immune responses. This review discusses the function of mTOR signaling in the differentiation and function of tissue-resident immune cells, with focus on the role of mTOR as a metabolic sensor and its impact on metabolic regulation in innate and adaptive immune cells. We also discuss the impact of metabolic constraints in tissues on immune homeostasis and disease, and how manipulating mTOR activity with drugs such as rapamycin can modulate immunity in these contexts. Copyright © 2017. Published by Elsevier Inc.

Targeting Tumor Vasculature with TNF Leads Effector T Cells to the Tumor and Enhances Therapeutic Efficacy of Immune Checkpoint Blockers in Combination with Adoptive Cell Therapy.

PubMed

Elia, Angela Rita; Grioni, Matteo; Basso, Veronica; Curnis, Flavio; Freschi, Massimo; Corti, Angelo; Mondino, Anna; Bellone, Matteo

2018-05-01

Purpose: Irregular blood flow and endothelial cell anergy, which characterize many solid tumors, hinder tumor infiltration by cytotoxic T lymphocytes (CTL). This confers resistance to cancer immunotherapy with monoclonal antibodies directed against regulatory pathways in T lymphocytes (i.e., immune checkpoint blockade, ICB). We investigated whether NGR-TNF, a TNF derivative capable of targeting the tumor vasculature, and improving intratumor infiltration by activated CTLs, could sensitize tumors to ICB with antibodies specific for the PD-1 and CTLA-4 receptors. Experimental Design: Transgenic adenocarcinoma of the mouse prostate (TRAMP) mice with autochthonous prostate cancer and C57BL/6 mice with orthotopic B16 melanoma were treated with NGR-TNF, adoptive T-cell therapy (ACT), and ICB, and monitored for immune surveillance and disease progression. Results: The combination of ACT, NGR-TNF, and ICB was the most effective in delaying disease progression, and in improving overall survival of mice bearing ICB-resistant prostate cancer or melanoma. Mechanistically, the therapeutic effects were associated with potent tumor infiltration, especially by endogenous but also by adoptively transferred PD-1 + , granzyme B + , and interferon-γ + CTLs. The therapeutic effects were also associated with favorable T-effector/regulatory T cell ratios. Conclusions: Targeting the tumor vasculature with low-dose TNF in association with ACT may represent a novel strategy for enhancing T-cell infiltration in tumors and overcoming resistance to immune checkpoint blockers. Clin Cancer Res; 24(9); 2171-81. ©2018 AACR . ©2018 American Association for Cancer Research.

Therapies targeting innate immunity for fighting inflammation in atherosclerosis.

PubMed

Mendel, Itzhak; Yacov, Niva; Harats, Dror; Breitbart, Eyal

2015-01-01

Atherosclerosis is a smoldering disease of the vasculature that can lead to the occlusion of the arteries, resulting in ischemia of the heart and brain. For many years, the asserted underlying mechanism of atherosclerosis, supported by its epidemiology, was based on the "cholesterol hypothesis" that people with high blood cholesterol are at higher risk of developing cardiovascular disease. This hypothesis instigated a vigorous search for treatment that yielded the generation of statins, which specifically reduce LDL cholesterol. Since then, statins have revolutionized the way people are treated for the prevention of atherosclerosis. Nonetheless, despite this potent class of drugs, cardiovascular disease continues to be the leading cause of death in many parts of the world, suggesting that additional mechanisms are involved in disease pathogenesis. Intensive research has revealed that the atherosclerotic plaque is enriched with leukocytes, and that macrophages constitute the majority of immune cells in the lesion. Monocytes/macrophages are now recognized as the prime immune cells involved in the development of atherosclerosis and are implicated to affect the size, composition and vulnerability of the atherosclerotic plaque. While many of the macrophage-derived pro-inflammatory mechanisms associated with atherogenesis have been characterized, such as cell adhesion, cytokine production and protease secretion, there is a dearth of drugs that specifically target innate immunity for treating patients with atherosclerosis. This review presents pre-clinical studies, and in most cases following clinical trials with antagonists and agonists that have been designed to counteract inflammation in atherosclerosis and associated diseases, highlighting targets expressed predominantly in monocytes.

Immune mechanisms in polymyositis and dermatomyositis and potential targets for therapy.

PubMed

Venalis, Paulius; Lundberg, Ingrid E

2014-03-01

PM and DM are characterized clinically by weakness and low endurance of skeletal muscle. Other organs are frequently involved, suggesting that idiopathic inflammatory myopathies (IIMs) are systemic inflammatory diseases. Involvement of immune mechanisms in IIMs is supported by the presence of T cells, macrophages and dendritic cells in muscle tissue, by the presence of autoantibodies and by HLA-DR being a strong genetic risk factor. T cells may have direct and indirect toxic effects on muscle fibres, causing muscle fibre necrosis and muscle weakness, but the target of the immune reaction is not known. A newly identified T cell subset, CD28(null) T cells, may have cytotoxic effects in the CD4(+) and CD8(+) T cell phenotype. These cells are apoptosis resistant and may contribute to treatment resistance. Several myositis-specific autoantibodies have been identified, but they are all directed against ubiquitously expressed autoantigens and the specificity of the T cell reactivity is not known. These autoantibodies are associated with distinct clinical phenotypes and some with distinct molecular pathways; e.g. sera from patients with anti-Jo-1 autoantibodies may activate the type I IFN system and these sera also contain high levels of B cell activating factor compared with other IIM subsets. The characterization of patients into subgroups based on autoantibody profiles seems to be a promising way to learn more about the specificities of the immune reactions. Careful phenotyping of infiltrating immune cells in muscle tissue before and after specific therapies and relating the molecular findings to clinical outcome measures may be another way to improve knowledge on specific immune mechanism in IIMs. Such information will be important for the development of new therapies.

Recent Advances in Aptamers Targeting Immune System.

PubMed

Hu, Piao-Ping

2017-02-01

The immune system plays important role in protecting the organism by recognizing non-self molecules from pathogen such as bacteria, parasitic worms, and viruses. When the balance of the host defense system is disturbed, immunodeficiency, autoimmunity, and inflammation occur. Nucleic acid aptamers are short single-stranded DNA (ssDNA) or RNA ligands that interact with complementary molecules with high specificity and affinity. Aptamers that target the molecules involved in immune system to modulate their function have great potential to be explored as new diagnostic and therapeutic agents for immune disorders. This review summarizes recent advances in the development of aptamers targeting immune system. The selection of aptamers with superior chemical and biological characteristics will facilitate their application in the diagnosis and treatment of immune disorders.

The innate immune system in host mice targets cells with allogenic mitochondrial DNA

PubMed Central

Ishikawa, Kaori; Nakada, Kazuto; Morimoto, Mami; Imanishi, Hirotake; Yoshizaki, Mariko; Sasawatari, Shigemi; Niikura, Mamoru; Takenaga, Keizo; Yonekawa, Hiromichi

2010-01-01

Mitochondrial DNA (mtDNA) has been proposed to be involved in respiratory function, and mtDNA mutations have been associated with aging, tumors, and various disorders, but the effects of mtDNA imported into transplants from different individuals or aged subjects have been unclear. We examined this issue by generating trans-mitochondrial tumor cells and embryonic stem cells that shared the syngenic C57BL/6 (B6) strain–derived nuclear DNA background but possessed mtDNA derived from allogenic mouse strains. We demonstrate that transplants with mtDNA from the NZB/B1NJ strain were rejected from the host B6 mice, not by the acquired immune system but by the innate immune system. This rejection was caused partly by NK cells and involved a MyD88-dependent pathway. These results introduce novel roles of mtDNA and innate immunity in tumor immunology and transplantation medicine. PMID:20937705

Immune cell phenotype and function in sepsis

PubMed Central

Rimmelé, Thomas; Payen, Didier; Cantaluppi, Vincenzo; Marshall, John; Gomez, Hernando; Gomez, Alonso; Murray, Patrick; Kellum, John A.

2015-01-01

Cells of the innate and adaptive immune systems play a critical role in the host response to sepsis. Moreover, their accessibility for sampling and their capacity to respond dynamically to an acute threat increases the possibility that leukocytes might serve as a measure of a systemic state of altered responsiveness in sepsis. The working group of the 14th Acute Dialysis Quality Initiative (ADQI) conference sought to obtain consensus on the characteristic functional and phenotypic changes in cells of the innate and adaptive immune system in the setting of sepsis. Techniques for the study of circulating leukocytes were also reviewed and the impact on cellular phenotypes and leukocyte function of non extracorporeal treatments and extracorporeal blood purification therapies proposed for sepsis was analyzed. A large number of alterations in the expression of distinct neutrophil and monocyte surface markers have been reported in septic patients. The most consistent alteration seen in septic neutrophils is their activation of a survival program that resists apoptotic death. Reduced expression of HLA-DR is a characteristic finding on septic monocytes but monocyte antimicrobial function does not appear to be significantly altered in sepsis. Regarding adaptive immunity, sepsis-induced apoptosis leads to lymphopenia in patients with septic shock and it involves all types of T cells (CD4, CD8 and Natural Killer) except T regulatory cells, thus favoring immunosuppression. Finally, numerous promising therapies targeting the host immune response to sepsis are under investigation. These potential treatments can have an effect on the number of immune cells, the proportion of cell subtypes and the cell function. PMID:26529661

IMMUNE CELL PHENOTYPE AND FUNCTION IN SEPSIS.

PubMed

Rimmelé, Thomas; Payen, Didier; Cantaluppi, Vincenzo; Marshall, John; Gomez, Hernando; Gomez, Alonso; Murray, Patrick; Kellum, John A

2016-03-01

Cells of the innate and adaptive immune systems play a critical role in the host response to sepsis. Moreover, their accessibility for sampling and their capacity to respond dynamically to an acute threat increases the possibility that leukocytes might serve as a measure of a systemic state of altered responsiveness in sepsis.The working group of the 14th Acute Dialysis Quality Initiative (ADQI) conference sought to obtain consensus on the characteristic functional and phenotypic changes in cells of the innate and adaptive immune system in the setting of sepsis. Techniques for the study of circulating leukocytes were also reviewed and the impact on cellular phenotypes and leukocyte function of nonextracorporeal treatments and extracorporeal blood purification therapies proposed for sepsis was analyzed.A large number of alterations in the expression of distinct neutrophil and monocyte surface markers have been reported in septic patients. The most consistent alteration seen in septic neutrophils is their activation of a survival program that resists apoptotic death. Reduced expression of HLA-DR is a characteristic finding on septic monocytes, but monocyte antimicrobial function does not appear to be significantly altered in sepsis. Regarding adaptive immunity, sepsis-induced apoptosis leads to lymphopenia in patients with septic shock and it involves all types of T cells (CD4, CD8, and Natural Killer) except T regulatory cells, thus favoring immunosuppression. Finally, numerous promising therapies targeting the host immune response to sepsis are under investigation. These potential treatments can have an effect on the number of immune cells, the proportion of cell subtypes, and the cell function.

5-Lipoxygenase Pathway, Dendritic Cells, and Adaptive Immunity

PubMed Central

Hedi, Harizi

2004-01-01

5-lipoxygenase (5-LO) pathway is the major source of potent proinflammatory leukotrienes (LTs) issued from the metabolism of arachidonic acid (AA), and best known for their roles in the pathogenesis of asthma. These lipid mediators are mainly released from myeloid cells and may act as physiological autocrine and paracrine signalling molecules, and play a central role in regulating the interaction between innate and adaptive immunity. The biological actions of LTs including their immunoregulatory and proinflammatory effects are mediated through extracellular specific G-protein-coupled receptors. Despite their role in inflammatory cells, such as neutrophils and macrophages, LTs may have important effects on dendritic cells (DC)-mediated adaptive immunity. Several lines of evidence show that DC not only are important source of LTs, but also become targets of their actions by producing other lipid mediators and proinflammatory molecules. This review focuses on advances in 5-LO pathway biology, the production of LTs from DC and their role on various cells of immune system and in adaptive immunity. PMID:15240920

Immune checkpoint inhibitors in small cell lung cancer.

PubMed

Pakkala, Suchita; Owonikoko, Taofeek K

2018-02-01

Small cell lung cancer (SCLC) is a rapidly progressive cancer that often debilitates patients within months of detection and quickly becomes refractory to the limited options of therapy. While SCLC is not generally considered an immunogenic tumor, clinical experience suggests that patients with robust immune response manifesting as paraneoplastic syndrome are more likely to present with limited stage of the disease and tend to have a better prognosis. Monoclonal antibodies targeting critical negative regulators of immune response, so called immune checkpoints, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) and programmed death 1 (PD-1) have expanded the application of immune-based therapies to increasing number of advanced stage cancers. These agents overcome the inhibitory immune signals leading to a heightened immune response against cancer cells. These immune checkpoint inhibitors have established efficacy leading to regulatory approval for their use in many cancer types including non-small cell lung cancer (NSCLC). Evaluation of the CTLA-4 inhibitor, ipilimumab and PD-1 inhibitors, nivolumab and pembrolizumab in SCLC have shown encouraging signal but definitive studies are still ongoing. In this review, we discuss the rationale behind the use of checkpoint inhibitors in SCLC, contextualize the results of early trials of immunotherapy agents in SCLC and project the future evolution of this strategy.

A dendritic cell-stromal axis maintains immune responses in lymph nodes

PubMed Central

Kumar, Varsha; Dasoveanu, Dragos C.; Chyou, Susan; Tzeng, Te-Chen; Rozo, Cristina; Liang, Yong; Stohl, William; Fu, Yang-Xin; Ruddle, Nancy; Lu, Theresa T.

2015-01-01

Summary Within secondary lymphoid tissues, stromal reticular cells support lymphocyte function, and targeting reticular cells is a potential strategy for controlling pathogenic lymphocytes in disease. However, the mechanisms that regulate reticular cell function are not well understood. Here we found that during an immune response in lymph nodes, dendritic cells (DCs) maintain reticular cell survival in multiple compartments. DC-derived lymphotoxin beta receptor (LTβR) ligands were critical mediators, and LTβR signaling on reticular cells mediated cell survival by modulating podoplanin (PDPN). PDPN modulated integrin-mediated cell adhesion, which maintained cell survival. This DC-stromal axis maintained lymphocyte survival and the ongoing immune response. Our findings provide insight into the functions of DCs, LTβR, and PDPN and delineate a DC-stromal axis that can potentially be targeted in autoimmune or lymphoproliferative diseases. PMID:25902483

Linking innate to adaptive immunity through dendritic cells.

PubMed

Steinman, Ralph M

2006-01-01

The function of dendritic cells (DCs) in linking innate to adaptive immunity is often summarized with two terms. DCs are sentinels, able to capture, process and present antigens and to migrate to lymphoid tissues to select rare, antigen-reactive T cell clones. DCs are also sensors, responding to a spectrum of environmental cues by extensive differentiation or maturation. The type of DC and the type of maturation induced by different stimuli influences the immunological outcome, such as the differentiation of Thl vs. Th2 T cells. Here we summarize the contributions of DCs to innate defences, particularly the production of immune enhancing cytokines and the activation of innate lymphocytes. Then we outline three innate features of DCs that influence peripheral tolerance and lead to adaptive immunity: a specialized endocytic system for antigen capture and processing, location and movements in vivo, and maturation in response to an array of stimuli. A new approach to the analysis of DC biology is to target antigens selectively to maturing DCs in vivo. This leads to stronger, more prolonged and broader (many immunogenic peptides) immunity by both T cells and B cells.

How do plants achieve immunity? Defence without specialized immune cells.

PubMed

Spoel, Steven H; Dong, Xinnian

2012-01-25

Vertebrates have evolved a sophisticated adaptive immune system that relies on an almost infinite diversity of antigen receptors that are clonally expressed by specialized immune cells that roam the circulatory system. These immune cells provide vertebrates with extraordinary antigen-specific immune capacity and memory, while minimizing self-reactivity. Plants, however, lack specialized mobile immune cells. Instead, every plant cell is thought to be capable of launching an effective immune response. So how do plants achieve specific, self-tolerant immunity and establish immune memory? Recent developments point towards a multilayered plant innate immune system comprised of self-surveillance, systemic signalling and chromosomal changes that together establish effective immunity.

ZFP36 RNA-binding proteins restrain T-cell activation and anti-viral immunity.

PubMed

Moore, Michael J; Blachere, Nathalie E; Fak, John J; Park, Christopher Y; Sawicka, Kirsty; Parveen, Salina; Zucker-Scharff, Ilana; Moltedo, Bruno; Rudensky, Alexander Y; Darnell, Robert B

2018-05-31

Dynamic post-transcriptional control of RNA expression by RNA-binding proteins (RBPs) is critical during immune response. ZFP36 RBPs are prominent inflammatory regulators linked to autoimmunity and cancer, but functions in adaptive immunity are less clear. We used HITS-CLIP to define ZFP36 targets in mouse T cells, revealing unanticipated actions in regulating T cell activation, proliferation, and effector functions. Transcriptome and ribosome profiling showed that ZFP36 represses mRNA target abundance and translation, notably through novel AU-rich sites in coding sequence. Functional studies revealed that ZFP36 regulates early T cell activation kinetics cell autonomously, by attenuating activation marker expression, limiting T cell expansion, and promoting apoptosis. Strikingly, loss of ZFP36 in vivo accelerated T cell responses to acute viral infection and enhanced anti-viral immunity. These findings uncover a critical role for ZFP36 RBPs in restraining T cell expansion and effector functions, and suggest ZFP36 inhibition as a strategy to enhance immune-based therapies. © 2018, Moore et al.

Strategies to Improve Vaccine Efficacy against Tuberculosis by Targeting Innate Immunity

PubMed Central

Schaible, Ulrich E.; Linnemann, Lara; Redinger, Natalja; Patin, Emmanuel C.; Dallenga, Tobias

2017-01-01

The global tuberculosis epidemic is the most common cause of death after infectious disease worldwide. Increasing numbers of infections with multi- and extensively drug-resistant variants of the Mycobacterium tuberculosis complex, resistant even to newly discovered and last resort antibiotics, highlight the urgent need for an efficient vaccine. The protective efficacy to pulmonary tuberculosis in adults of the only currently available vaccine, M. bovis BCG, is unsatisfactory and geographically diverse. More importantly, recent clinical studies on new vaccine candidates did not prove to be better than BCG, yet. Here, we propose and discuss novel strategies to improve efficacy of existing anti-tuberculosis vaccines. Modulation of innate immune responses upon vaccination already provided promising results in animal models of tuberculosis. For instance, neutrophils have been shown to influence vaccine efficacy, both, positively and negatively, and stimulate specific antibody secretion. Modulating immune regulatory properties after vaccination such as induction of different types of innate immune cell death, myeloid-derived suppressor or regulatory T cells, production of anti-inflammatory cytokines such as IL-10 may have beneficial effects on protection efficacy. Incorporation of lipid antigens presented via CD1 molecules to T cells have been discussed as a way to enhance vaccine efficacy. Finally, concepts of dendritic cell-based immunotherapies or training the innate immune memory may be exploitable for future vaccination strategies against tuberculosis. In this review, we put a spotlight on host immune networks as potential targets to boost protection by old and new tuberculosis vaccines. PMID:29312298

Strategies to Improve Vaccine Efficacy against Tuberculosis by Targeting Innate Immunity.

PubMed

Schaible, Ulrich E; Linnemann, Lara; Redinger, Natalja; Patin, Emmanuel C; Dallenga, Tobias

2017-01-01

The global tuberculosis epidemic is the most common cause of death after infectious disease worldwide. Increasing numbers of infections with multi- and extensively drug-resistant variants of the Mycobacterium tuberculosis complex, resistant even to newly discovered and last resort antibiotics, highlight the urgent need for an efficient vaccine. The protective efficacy to pulmonary tuberculosis in adults of the only currently available vaccine, M. bovis BCG, is unsatisfactory and geographically diverse. More importantly, recent clinical studies on new vaccine candidates did not prove to be better than BCG, yet. Here, we propose and discuss novel strategies to improve efficacy of existing anti-tuberculosis vaccines. Modulation of innate immune responses upon vaccination already provided promising results in animal models of tuberculosis. For instance, neutrophils have been shown to influence vaccine efficacy, both, positively and negatively, and stimulate specific antibody secretion. Modulating immune regulatory properties after vaccination such as induction of different types of innate immune cell death, myeloid-derived suppressor or regulatory T cells, production of anti-inflammatory cytokines such as IL-10 may have beneficial effects on protection efficacy. Incorporation of lipid antigens presented via CD1 molecules to T cells have been discussed as a way to enhance vaccine efficacy. Finally, concepts of dendritic cell-based immunotherapies or training the innate immune memory may be exploitable for future vaccination strategies against tuberculosis. In this review, we put a spotlight on host immune networks as potential targets to boost protection by old and new tuberculosis vaccines.

Modulation of Immune Cell Functions by the E3 Ligase Cbl-b

PubMed Central

Lutz-Nicoladoni, Christina; Wolf, Dominik; Sopper, Sieghart

2015-01-01

Maintenance of immunological tolerance is a critical hallmark of the immune system. Several signaling checkpoints necessary to balance activating and inhibitory input to immune cells have been described so far, among which the E3 ligase Cbl-b appears to be a central player. Cbl-b is expressed in all leukocyte subsets and regulates several signaling pathways in T cells, NK cells, B cells, and different types of myeloid cells. In most cases, Cbl-b negatively regulates activation signals through antigen or pattern recognition receptors and co-stimulatory molecules. In line with this function, cblb-deficient immune cells display lower activation thresholds and cblb knockout mice spontaneously develop autoimmunity and are highly susceptible to experimental autoimmunity. Interestingly, genetic association studies link CBLB-polymorphisms with autoimmunity also in humans. Vice versa, the increased activation potential of cblb-deficient cells renders them more potent to fight against malignancies or infections. Accordingly, several reports have shown that cblb knockout mice reject tumors, which mainly depends on cytotoxic T and NK cells. Thus, targeting Cbl-b may be an interesting strategy to enhance anti-cancer immunity. In this review, we summarize the findings on the molecular function of Cbl-b in different cell types and illustrate the potential of Cbl-b as target for immunomodulatory therapies. PMID:25815272

A Combination of Immune Checkpoint Inhibition with Metronomic Chemotherapy as a Way of Targeting Therapy-Resistant Cancer Cells.

PubMed

Kareva, Irina

2017-10-13

Therapeutic resistance remains a major obstacle in treating many cancers, particularly in advanced stages. It is likely that cytotoxic lymphocytes (CTLs) have the potential to eliminate therapy-resistant cancer cells. However, their effectiveness may be limited either by the immunosuppressive tumor microenvironment, or by immune cell death induced by cytotoxic treatments. High-frequency low-dose (also known as metronomic) chemotherapy can help improve the activity of CTLs by providing sufficient stimulation for cytotoxic immune cells without excessive depletion. Additionally, therapy-induced removal of tumor cells that compete for shared nutrients may also facilitate tumor infiltration by CTLs, further improving prognosis. Metronomic chemotherapy can also decrease the number of immunosuppressive cells in the tumor microenvironment, including regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Immune checkpoint inhibition can further augment anti-tumor immune responses by maintaining T cells in an activated state. Combining immune checkpoint inhibition with metronomic administration of chemotherapeutic drugs may create a synergistic effect that augments anti-tumor immune responses and clears metabolic competition. This would allow immune-mediated elimination of therapy-resistant cancer cells, an effect that may be unattainable by using either therapeutic modality alone.

[Exosomes and Immune Cells].

PubMed

Seo, Naohiro

2017-05-01

In addition to the cytokines and cytotoxic granules, exosomes have been known as the intercellular communicator and cytotoxic missile of immune cells for the past decade. It has been well known that mature dendritic cell(DC)-derived exosomes participate in the T cell and natural killer(NK)cell activation, while immature DCs secrete tolerogenic exosomes for regulatory T(Treg)cell generation. Treg cell-derived EVs act as a suppressor against pathogenic type-1 T helper(Th1)cell responses. CD8+ T cells produce tumoricidal exosomes for preventing tumor invasion and metastasis transiently after T cell receptor(TCR)-mediated stimulation. Thus, immune cells produce functional exosomes in the activation state- and/or differentiation stage-dependent manner. In this review, the role of immune cell-derived exosomes will be introduced, focusing mainly on immune reaction against tumor.

Follicular helper T cells in immunity and systemic autoimmunity.

PubMed

Craft, Joseph E

2012-05-01

Follicular helper T (T(FH)) cells are essential for B-cell maturation and immunoglobulin production after immunization with thymus-dependent antigens. Nevertheless, the development and function of T(FH) cells have been less clearly defined than classic CD4(+) effector T-cell subsets, including T-helper-1 (T(H)1), T(H)2 and T(H)17 cells. As such, our understanding of the genesis of T(FH) cells in humans and their role in the development of autoimmunity remains incomplete. However, evidence from animal models of systemic lupus erythematosus (SLE) and patients with systemic autoimmune diseases suggests that these cells are necessary for pathogenic autoantibody production, in a manner analogous to their role in promotion of B-cell maturation during normal immune responses. In this Review, I discuss the findings that have increased our knowledge of T(FH)-cell development and function in normal and aberrant immune responses. Such information might improve our understanding of autoimmune diseases, such as SLE, and highlights the potential of T(FH) cells as therapeutic targets in these diseases.

Activation of B Cells by a Dendritic Cell-Targeted Oral Vaccine

PubMed Central

Sahay, Bikash; Owen, Jennifer L.; Yang, Tao; Zadeh, Mojgan; Lightfoot, Yaíma L.; Ge, Jun-Wei; Mohamadzadeh, Mansour

2015-01-01

Production of long-lived, high affinity humoral immunity is an essential characteristic of successful vaccination and requires cognate interactions between T and B cells in germinal centers. Within germinal centers, specialized T follicular helper cells assist B cells and regulate the antibody response by mediating the differentiation of B cells into memory or plasma cells after exposure to T cell-dependent antigens. It is now appreciated that local immune responses are also essential for protection against infectious diseases that gain entry to the host by the mucosal route; therefore, targeting the mucosal compartments is the optimum strategy to induce protective immunity. However, because the gastrointestinal mucosae are exposed to large amounts of environmental and dietary antigens on a daily basis, immune regulatory mechanisms exist to favor tolerance and discourage autoimmunity at these sites. Thus, mucosal vaccination strategies must ensure that the immunogen is efficiently taken up by the antigen presenting cells, and that the vaccine is capable of activating humoral and cellular immunity, while avoiding the induction of tolerance. Despite significant progress in mucosal vaccination, this potent platform for immunotherapy and disease prevention must be further explored and refined. Here we discuss recent progress in the understanding of the role of different phenotypes of B cells in the development of an efficacious mucosal vaccine against infectious disease. PMID:24372255

Crosstalk between cancer and immune cells: role of STAT3 in the tumour microenvironment.

PubMed

Yu, Hua; Kortylewski, Marcin; Pardoll, Drew

2007-01-01

Immune cells in the tumour microenvironment not only fail to mount an effective anti-tumour immune response, but also interact intimately with the transformed cells to promote oncogenesis actively. Signal transducer and activator of transcription 3 (STAT3), which is a point of convergence for numerous oncogenic signalling pathways, is constitutively activated both in tumour cells and in immune cells in the tumour microenvironment. Constitutively activated STAT3 inhibits the expression of mediators necessary for immune activation against tumour cells. Furthermore, STAT3 activity promotes the production of immunosuppressive factors that activate STAT3 in diverse immune-cell subsets, altering gene-expression programmes and, thereby, restraining anti-tumour immune responses. As such, STAT3 propagates several levels of crosstalk between tumour cells and their immunological microenvironment, leading to tumour-induced immunosuppression. Consequently, STAT3 has emerged as a promising target for cancer immunotherapy.

Single-cell transcriptome analysis of fish immune cells provides insight into the evolution of vertebrate immune cell types

PubMed Central

Ferreira, Lauren; Macaulay, Iain C.; Stubbington, Michael J.T.

2017-01-01

The immune system of vertebrate species consists of many different cell types that have distinct functional roles and are subject to different evolutionary pressures. Here, we first analyzed conservation of genes specific for all major immune cell types in human and mouse. Our results revealed higher gene turnover and faster evolution of trans-membrane proteins in NK cells compared with other immune cell types, and especially T cells, but similar conservation of nuclear and cytoplasmic protein coding genes. To validate these findings in a distant vertebrate species, we used single-cell RNA sequencing of lck:GFP cells in zebrafish and obtained the first transcriptome of specific immune cell types in a nonmammalian species. Unsupervised clustering and single-cell TCR locus reconstruction identified three cell populations, T cells, a novel type of NK-like cells, and a smaller population of myeloid-like cells. Differential expression analysis uncovered new immune-cell–specific genes, including novel immunoglobulin-like receptors, and neofunctionalization of recently duplicated paralogs. Evolutionary analyses confirmed the higher gene turnover of trans-membrane proteins in NK cells compared with T cells in fish species, suggesting that this is a general property of immune cell types across all vertebrates. PMID:28087841

Applying Convergent Immunity to Innovative Vaccines Targeting Staphylococcus aureus

PubMed Central

Yeaman, Michael R.; Filler, Scott G.; Schmidt, Clint S.; Ibrahim, Ashraf S.; Edwards, John E.; Hennessey, John P.

2014-01-01

Recent perspectives forecast a new paradigm for future “third generation” vaccines based on commonalities found in diverse pathogens or convergent immune defenses to such pathogens. For Staphylococcus aureus, recurring infections and a limited success of vaccines containing S. aureus antigens imply that native antigens induce immune responses insufficient for optimal efficacy. These perspectives exemplify the need to apply novel vaccine strategies to high-priority pathogens. One such approach can be termed convergent immunity, where antigens from non-target organisms that contain epitope homologs found in the target organism are applied in vaccines. This approach aims to evoke atypical immune defenses via synergistic processes that (1) afford protective efficacy; (2) target an epitope from one organism that contributes to protective immunity against another; (3) cross-protect against multiple pathogens occupying a common anatomic or immunological niche; and/or (4) overcome immune subversion or avoidance strategies of target pathogens. Thus, convergent immunity has a potential to promote protective efficacy not usually elicited by native antigens from a target pathogen. Variations of this concept have been mainstays in the history of viral and bacterial vaccine development. A more far-reaching example is the pre-clinical evidence that specific fungal antigens can induce cross-kingdom protection against bacterial pathogens. This trans-kingdom protection has been demonstrated in pre-clinical studies of the recombinant Candida albicans agglutinin-like sequence 3 protein (rAls3) where it was shown that a vaccine containing rAls3 provides homologous protection against C. albicans, heterologous protection against several other Candida species, and convergent protection against several strains of S. aureus. Convergent immunity reflects an intriguing new approach to designing and developing vaccine antigens and is considered here in the context of vaccines to target S

Hyperactive immune cells (T cells) may be responsible for acute lung injury in influenza virus infections: a need for early immune-modulators for severe cases.

PubMed

Lee, Kyung-Yil; Rhim, Jung-Woo; Kang, Jin-Han

2011-01-01

It has been believed that acute lung injury in influenza virus infections is caused by a virus-induced cytopathy; viruses that have multiplied in the upper respiratory tract spread to lung tissues along the lower respiratory tract. However, some experimental and clinical studies have suggested that the pathogenesis of acute lung injury in influenza virus infections is associated with excessive host response including a cell-mediated immune reaction. During the pandemic H1N1 2009 influenza A virus infections in Korea, we experienced a dramatic effect of immune-modulators (corticosteroids) on the patients with severe pneumonia who had significant respiratory distress at presentation and those who showed rapidly progressive pneumonia during oseltamivir treatment. We also found that the pneumonia patients treated with corticosteroids showed the lowest lymphocyte differential and that the severity of pneumonia was associated with the lymphocyte count at presentation. From our findings and previous experimental and clinical studies, we postulated that hyperactive immune cells (T cells) may be involved in the acute lung injury of influenza virus infections, using a hypothesis of 'protein homeostasis system'; the inducers of the cell-mediated immune response are initially produced at the primary immune sites by the innate immune system. These substances reach the lung cells, the main target organ, via the systemic circulation, and possibly the cells of other organs, including myocytes or central nerve system cells, leading to extrapulmonary symptoms (e.g., myalgia and rhabdomyolysis, and encephalopathy). To control these substances that may be possibly toxic to host cells, the adaptive immune reaction may be operated by immune cells, mainly lymphocytes. Hyperimmune reaction of immune cells produces higher levels of cytokines which may be associated with acute lung injury, and may be controlled by early use of immune-modulators. Early initiation and proper dosage of immune

Single-cell transcriptome analysis of fish immune cells provides insight into the evolution of vertebrate immune cell types.

PubMed

Carmona, Santiago J; Teichmann, Sarah A; Ferreira, Lauren; Macaulay, Iain C; Stubbington, Michael J T; Cvejic, Ana; Gfeller, David

2017-03-01

The immune system of vertebrate species consists of many different cell types that have distinct functional roles and are subject to different evolutionary pressures. Here, we first analyzed conservation of genes specific for all major immune cell types in human and mouse. Our results revealed higher gene turnover and faster evolution of trans -membrane proteins in NK cells compared with other immune cell types, and especially T cells, but similar conservation of nuclear and cytoplasmic protein coding genes. To validate these findings in a distant vertebrate species, we used single-cell RNA sequencing of lck:GFP cells in zebrafish and obtained the first transcriptome of specific immune cell types in a nonmammalian species. Unsupervised clustering and single-cell TCR locus reconstruction identified three cell populations, T cells, a novel type of NK-like cells, and a smaller population of myeloid-like cells. Differential expression analysis uncovered new immune-cell-specific genes, including novel immunoglobulin-like receptors, and neofunctionalization of recently duplicated paralogs. Evolutionary analyses confirmed the higher gene turnover of trans -membrane proteins in NK cells compared with T cells in fish species, suggesting that this is a general property of immune cell types across all vertebrates. © 2017 Carmona et al.; Published by Cold Spring Harbor Laboratory Press.

Recent advances targeting innate immunity-mediated therapies against HIV-1 infection.

PubMed

Shankar, Esaki Muthu; Velu, Vijayakumar; Vignesh, Ramachandran; Vijayaraghavalu, Sivakumar; Rukumani, Devi Velayuthan; Sabet, Negar Shafiei

2012-08-01

Early defence mechanisms of innate immunity respond rapidly to infection against HIV-1 in the genital mucosa. Additionally, innate immunity optimises effective adaptive immune responses against persistent HIV infection. Recent research has highlighted the intrinsic roles of apolipoprotein B mRNA-editing, enzyme-catalytic, polypeptide-like 3G, tripartite motif-containing protein 5, tetherin, sterile α-motif and histidine/aspartic acid domain-containing protein 1 in restricting HIV-1 replication. Likewise, certain endogenously secreted antimicrobial peptides, namely α/β/θ-defensins, lactoferrins, secretory leukocyte protease inhibitor, trappin-2/elafin and macrophage inflammatory protein-3α are reportedly protective. Whilst certain factors directly inhibit HIV, others can be permissive. Interferon-λ3 exerts an anti-HIV function by activating Janus kinase-signal transducer and activator of transcription-mediated innate responses. Morphine has been found to impair intracellular innate immunity, contributing to HIV establishment in macrophages. Interestingly, protegrin-1 could be used therapeutically to inhibit early HIV-1 establishment. Moreover, chloroquine inhibits plasmacytoid dendritic cell activation and improves effective T-cell responses. This minireview summarizes the recently identified targets for innate immunity-mediated therapies and outlines the challenges that lie ahead in improving treatment of HIV infection. © 2012 The Societies and Blackwell Publishing Asia Pty Ltd.

Engineering Immunity: Modulating Dendritic Cell Subsets and Lymph Node Response to Direct Immune-polarization and Vaccine Efficacy

PubMed Central

Leleux, Jardin; Atalis, Alexandra; Roy, Krishnendu

2017-01-01

While successful vaccines have been developed against many pathogens, there are still many diseases and pathogenic infections that are highly evasive to current vaccination strategies. Thus, more sophisticated approaches to control the type and quality of vaccine-induced immune response must be developed. Dendritic cells (DCs) are the sentinels of the body and play a critical role in immune response generation and direction by bridging innate and adaptive immunity. It is now well recognized that DCs can be separated into many subgroups, each of which has a unique function. Better understanding of how various DC subsets, in lymphoid organs and in the periphery, can be targeted through controlled delivery; and how these subsets modulate and control the resulting immune response could greatly enhance our ability to develop new, effective vaccines against complex diseases. In this review, we provide an overview of DC subset biology and discuss current immunotherapeutic strategies that utilize DC targeting to modulate and control immune responses. PMID:26489733

NLRC5/MHC class I transactivator is a target for immune evasion in cancer

PubMed Central

Yoshihama, Sayuri; Roszik, Jason; Downs, Isaac; Meissner, Torsten B.; Vijayan, Saptha; Chapuy, Bjoern; Sidiq, Tabasum; Shipp, Margaret A.; Lizee, Gregory A.; Kobayashi, Koichi S.

2016-01-01

Cancer cells develop under immune surveillance, thus necessitating immune escape for successful growth. Loss of MHC class I expression provides a key immune evasion strategy in many cancers, although the molecular mechanisms remain elusive. MHC class I transactivator (CITA), known as “NLRC5” [NOD-like receptor (NLR) family, caspase recruitment (CARD) domain containing 5], has recently been identified as a critical transcriptional coactivator of MHC class I gene expression. Here we show that the MHC class I transactivation pathway mediated by CITA/NLRC5 constitutes a target for cancer immune evasion. In all the 21 tumor types we examined, NLRC5 expression was highly correlated with the expression of MHC class I, with cytotoxic T-cell markers, and with genes in the MHC class I antigen-presentation pathway, including LMP2/LMP7, TAP1, and β2-microglobulin. Epigenetic and genetic alterations in cancers, including promoter methylation, copy number loss, and somatic mutations, were most prevalent in NLRC5 among all MHC class I-related genes and were associated with the impaired expression of components of the MHC class I pathway. Strikingly, NLRC5 expression was significantly associated with the activation of CD8+ cytotoxic T cells and patient survival in multiple cancer types. Thus, NLRC5 constitutes a novel prognostic biomarker and potential therapeutic target of cancers. PMID:27162338

NLRC5/MHC class I transactivator is a target for immune evasion in cancer.

PubMed

Yoshihama, Sayuri; Roszik, Jason; Downs, Isaac; Meissner, Torsten B; Vijayan, Saptha; Chapuy, Bjoern; Sidiq, Tabasum; Shipp, Margaret A; Lizee, Gregory A; Kobayashi, Koichi S

2016-05-24

Cancer cells develop under immune surveillance, thus necessitating immune escape for successful growth. Loss of MHC class I expression provides a key immune evasion strategy in many cancers, although the molecular mechanisms remain elusive. MHC class I transactivator (CITA), known as "NLRC5" [NOD-like receptor (NLR) family, caspase recruitment (CARD) domain containing 5], has recently been identified as a critical transcriptional coactivator of MHC class I gene expression. Here we show that the MHC class I transactivation pathway mediated by CITA/NLRC5 constitutes a target for cancer immune evasion. In all the 21 tumor types we examined, NLRC5 expression was highly correlated with the expression of MHC class I, with cytotoxic T-cell markers, and with genes in the MHC class I antigen-presentation pathway, including LMP2/LMP7, TAP1, and β2-microglobulin. Epigenetic and genetic alterations in cancers, including promoter methylation, copy number loss, and somatic mutations, were most prevalent in NLRC5 among all MHC class I-related genes and were associated with the impaired expression of components of the MHC class I pathway. Strikingly, NLRC5 expression was significantly associated with the activation of CD8(+) cytotoxic T cells and patient survival in multiple cancer types. Thus, NLRC5 constitutes a novel prognostic biomarker and potential therapeutic target of cancers.

The intersection of cancer, cancer stem cells, and the immune system: therapeutic opportunities.

PubMed

Silver, Daniel J; Sinyuk, Maksim; Vogelbaum, Michael A; Ahluwalia, Manmeet S; Lathia, Justin D

2016-02-01

During brain neoplasia, malignant cells subjugate the immune system to provide an environment that favors tumor growth. These mechanisms capitalize on tumor-promoting functions of various immune cell types and typically result in suppression of tumor immune rejection. Immunotherapy efforts are underway to disrupt these mechanisms and turn the immune system against developing tumors. While many of these therapies are already in early-stage clinical trials, understanding how these therapies impact various tumor cell populations, including self-renewing cancer stem cells, may help to predict their efficacy and clarify their mechanisms of action. Moreover, interrogating the biology of glioma cell, cancer stem cell, and immune cell interactions may provide additional therapeutic targets to leverage against disease progression. In this review, we begin by highlighting a series of investigations into immune cell-mediated tumor promotion that do not parse the tumor into stem and non-stem components. We then take a closer look at the immune-suppressive mechanisms derived specifically from cancer stem cell interactions with the immune system and end with an update on immunotherapy and cancer stem cell-directed clinical trials in glioblastoma. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

New generation of oral mucosal vaccines targeting dendritic cells

PubMed Central

Owen, Jennifer L.; Sahay, Bikash; Mohamadzadeh, Mansour

2013-01-01

As most infectious organisms gain entry at mucosal surfaces, there is a great deal of interest in developing vaccines that elicit effective mucosal immune responses against pathogen challenge. Targeted vaccination is one of the most effective methods available to prevent and control infectious diseases. Mucosal vaccines can offer lower costs, better accessibility, needle free delivery, and a higher capacity for mass immunizations during pandemics. Both local mucosal immunity and robust systemic responses can be achieved through mucosal vaccination. Recent progress in understanding the molecular and cellular components of the mucosal immune system have allowed for the development of a novel mucosal vaccine platform utilizing specific dendritic cell-targeting peptides and orally administered lactobacilli to elicit efficient antigen specific immune responses against infections, including B. anthracis in experimental models of disease. PMID:23835515

Pregnancy immunology: decidual immune cells.

PubMed

Sanguansermsri, Donruedee; Pongcharoen, Sutatip

2008-01-01

Human pregnancy is a complex process. Placental development depends on the function of secretory molecules produced by placental trophoblast cells as well as by maternal uterine immune cells within the decidua. These decidual immune cells are T cells, natural killer cells, macrophages and dendritic cells. The interactions between the trophoblast cells and the maternal immune cells have an impact on the outcome of the pregnancy. Knowledge about the phenotypes and functions of the maternal immune cells in normal and pathological pregnancies including recurrent spontaneous abortions, preeclampsia and hydatidiform moles may improve our understanding of the immunobiology of the normal pregnancy as a whole and may provide approaches for improving the treatment of pathological pregnancies.

VEGFR2-targeted fusion antibody improved NK cell-mediated immunosurveillance against K562 cells.

PubMed

Ren, Xueyan; Xie, Wei; Wang, Youfu; Xu, Menghuai; Liu, Fang; Tang, Mingying; Li, Chenchen; Wang, Min; Zhang, Juan

2016-08-01

MHC class I polypeptide-related sequence A (MICA), which is normally expressed on cancer cells, activates NK cells via NK group 2-member D pathway. However, some cancer cells escape NK-mediated immune surveillance by shedding membrane MICA causing immune suppression. To address this issue, we designed an antibody-MICA fusion targeting tumor-specific antigen (vascular endothelial growth factor receptor 2, VEGFR2) based on our patented antibody (mAb04) against VEGFR2. In vitro results demonstrate that the fusion antibody retains both the antineoplastic and the immunomodulatory activity of mAb04. Further, we revealed that it enhanced NK-mediated immunosurveillance against K562 cells through increasing degranulation and cytokine production of NK cells. The overall data suggest our new fusion protein provides a promising approach for cancer-targeted immunotherapy and has prospects for potential application of chronic myeloid leukemia.

Drug Hypersensitivity: How Drugs Stimulate T Cells via Pharmacological Interaction with Immune Receptors.

PubMed

Pichler, Werner J; Adam, Jacqueline; Watkins, Stephen; Wuillemin, Natascha; Yun, James; Yerly, Daniel

2015-01-01

Small chemicals like drugs tend to bind to proteins via noncovalent bonds, e.g. hydrogen bonds, salt bridges or electrostatic interactions. Some chemicals interact with other molecules than the actual target ligand, representing so-called 'off-target' activities of drugs. Such interactions are a main cause of adverse side effects to drugs and are normally classified as predictable type A reactions. Detailed analysis of drug-induced immune reactions revealed that off-target activities also affect immune receptors, such as highly polymorphic human leukocyte antigens (HLA) or T cell receptors (TCR). Such drug interactions with immune receptors may lead to T cell stimulation, resulting in clinical symptoms of delayed-type hypersensitivity. They are assigned the 'pharmacological interaction with immune receptors' (p-i) concept. Analysis of p-i has revealed that drugs bind preferentially or exclusively to distinct HLA molecules (p-i HLA) or to distinct TCR (p-i TCR). P-i reactions differ from 'conventional' off-target drug reactions as the outcome is not due to the effect on the drug-modified cells themselves, but is the consequence of reactive T cells. Hence, the complex and diverse clinical manifestations of delayed-type hypersensitivity are caused by the functional heterogeneity of T cells. In the abacavir model of p-i HLA, the drug binding to HLA may result in alteration of the presenting peptides. More importantly, the drug binding to HLA generates a drug-modified HLA, which stimulates T cells directly, like an allo-HLA. In the sulfamethoxazole model of p-i TCR, responsive T cells likely require costimulation for full T cell activation. These findings may explain the similarity of delayed-type hypersensitivity reactions to graft-versus-host disease, and how systemic viral infections increase the risk of delayed-type hypersensitivity reactions. © 2015 The Author(s) Published by S. Karger AG, Basel.

Protective antitumor activity through dendritic cell immunization is mediated by NK cell as well as CTL activation.

PubMed

Kim, K D; Kim, J K; Kim, S J; Choe, I S; Chung, T H; Choe, Y K; Lim, J S

1999-08-01

Dendritic cells (DCs) are potent professional antigen-presenting cells (APC) capable of inducing the primary T cell response to antigen. Although tumor cells express target antigens, they are incapable of stimulating a tumor-specific immune response due to a defect in the costimulatory signal that is required for optimal activation of T cells. In this work, we describe a new approach using tumor-DC coculture to improve the antigen presenting capacity of tumor cells, which does not require a source of tumor-associated antigen. Immunization of a weakly immunogenic and progressive tumor cocultured with bone marrow-derived DCs generated an effective tumor vaccine. Immunization with the cocultured DCs was able to induce complete protective immunity against tumor challenges and was effective for the induction of tumor-specific CTL (cytotoxic T lymphocyte) activity. Furthermore, high NK cell activity was observed in mice in which tumors were rejected. In addition, immunization with tumor-pulsed DCs induced delayed tumor growth, but not tumor eradication in tumor-bearing mice. Our results demonstrate that coculture of DCs with tumors generated antitumor immunity due to the NK cell activation as well as tumor-specific T cell. This approach would be useful for designing tumor vaccines using DCs when the information about tumor antigens is limited.

Neuro-immune dysfunction during brain aging: new insights in microglial cell regulation.

PubMed

Matt, Stephanie M; Johnson, Rodney W

2016-02-01

Microglia, the resident immune cells of the brain, are at the center of communication between the central nervous system and immune system. While these brain-immune interactions are balanced in healthy adulthood, the ability to maintain homeostasis during aging is impaired. Microglia develop a loss of integrated regulatory networks including aberrant signaling from other brain cells, immune sensors, and epigenetic modifiers. The low-grade chronic neuroinflammation associated with this dysfunctional activity likely contributes to cognitive deficits and susceptibility to age-related pathologies. A better understanding of the underlying mechanisms responsible for neuro-immune dysregulation with age is crucial for providing targeted therapeutic strategies to support brain repair and healthy aging. Copyright © 2015 Elsevier Ltd. All rights reserved.

Elimination of tumor by CD47/PD-L1 dual-targeting fusion protein that engages innate and adaptive immune responses.

PubMed

Liu, Boning; Guo, Huaizu; Xu, Jin; Qin, Ting; Guo, Qingcheng; Gu, Nana; Zhang, Dapeng; Qian, Weizhu; Dai, Jianxin; Hou, Sheng; Wang, Hao; Guo, Yajun

The host immune system generally serves as a barrier against tumor formation. Programmed death-ligand 1 (PD-L1) is a critical "don't find me" signal to the adaptive immune system, whereas CD47 transmits an anti-phagocytic signal, known as the "don't eat me" signal, to the innate immune system. These and similar immune checkpoints are often overexpressed on human tumors. Thus, dual targeting both innate and adaptive immune checkpoints would likely maximize anti-tumor therapeutic effect and elicit more durable responses. Herein, based on the variable region of atezolizumab and consensus variant 1 (CV1) monomer, we constructed a dual-targeting fusion protein targeting both CD47 and PD-L1 using "Knobs-into-holes" technology, denoted as IAB. It was effective in inducing phagocytosis of tumor cells, stimulating T-cell activation and mediating antibody-dependent cell-mediated cytotoxicity in vitro. No obvious sign of hematological toxicity was observed in mice administered IAB at a dose of 100 mg/kg, and IAB exhibited potent antitumor activity in an immune-competent mouse model of MC38. Additionally, the anti-tumor effect of IAB was impaired by anti-CD8 antibody or clodronate liposomes, which implied that both CD8+ T cells and macrophages were required for the anti-tumor efficacy of IAB and IAB plays an essential role in the engagement of innate and adaptive immune responses. Collectively, these results demonstrate the capacity of an elicited endogenous immune response against tumors and elucidate essential characteristics of synergistic innate and adaptive immune response, and indicate dual blockade of CD47 and PD-L1 by IAB may be a synergistic therapy that activates both innate and adaptive immune response against tumors.

Improved targeted immunization strategies based on two rounds of selection

NASA Astrophysics Data System (ADS)

Xia, Ling-Ling; Song, Yu-Rong; Li, Chan-Chan; Jiang, Guo-Ping

2018-04-01

In the case of high degree targeted immunization where the number of vaccine is limited, when more than one node associated with the same degree meets the requirement of high degree centrality, how can we choose a certain number of nodes from those nodes, so that the number of immunized nodes will not exceed the limit? In this paper, we introduce a new idea derived from the selection process of second-round exam to solve this problem and then propose three improved targeted immunization strategies. In these proposed strategies, the immunized nodes are selected through two rounds of selection, where we increase the quotas of first-round selection according the evaluation criterion of degree centrality and then consider another characteristic parameter of node, such as node's clustering coefficient, betweenness and closeness, to help choose targeted nodes in the second-round selection. To validate the effectiveness of the proposed strategies, we compare them with the degree immunizations including the high degree targeted and the high degree adaptive immunizations using two metrics: the size of the largest connected component of immunized network and the number of infected nodes. Simulation results demonstrate that the proposed strategies based on two rounds of sorting are effective for heterogeneous networks and their immunization effects are better than that of the degree immunizations.

Targeting with bovine CD154 enhances humoral immune responses induced by a DNA vaccine in sheep.

PubMed

Manoj, Sharmila; Griebel, Philip J; Babiuk, Lorne A; van Drunen Littel-van den Hurk, Sylvia

2003-01-15

CD40-CD154 interactions play an important role in regulating humoral and cell-mediated immune responses. Recently, these interactions have been exploited for the development of therapeutic and preventive treatments. The objective of this study was to test the ability of bovine CD154 to target a plasmid-encoded Ag to CD40-expressing APCs. To achieve this, a plasmid coding for bovine CD154 fused to a truncated secreted form of bovine herpesvirus 1 glycoprotein D (tgD), pSLIAtgD-CD154, was constructed. The chimeric tgD-CD154 was expressed in vitro in COS-7 cells and reacted with both glycoprotein D- and CD154-specific Abs. Both tgD and tgD-CD154 were capable of binding to epithelial cells, whereas only tgD-CD154 bound to B cells. Furthermore, dual-labeling of ovine PBMCs revealed that tgD-CD154 was bound by primarily B cells. The functional integrity of the tgD-CD154 chimera was confirmed by the induction of both IL-4-dependent B cell proliferation and tgD-specific lymphoproliferative responses in vitro. Finally, sheep immunized with pSLIAtgD-CD154 developed a more rapid primary tgD-specific Ab response and a significantly stronger tgD-specific secondary response when compared with animals immunized with pSLIAtgD and control animals. Similarly, virus-neutralizing Ab titers were significantly higher after secondary immunization with pSLIAtgD-CD154. These results demonstrate that using CD154 to target plasmid-expressed Ag can significantly enhance immune responses induced by a DNA vaccine.

Targeting antigens to Dec-205 on dendritic cells induces a higher immune response in chickens: Hemagglutinin of avian influenza virus example.

PubMed

Jáuregui-Zúñiga, David; Pedraza-Escalona, Martha; Espino-Solís, Gerardo Pavel; Quintero-Hernández, Verónica; Olvera-Rodríguez, Alejandro; Díaz-Salinas, Marco Aurelio; López, Susana; Possani, Lourival Domingos

2017-04-01

It is widely known that targeting a variety of antigens to the DEC-205 receptor on dendritic cells (DCs) significantly potentiate immunity. This communication reports the development of a new murine monoclonal antibody (mAb) against the chicken DEC-205, using as immunogen the carbohydrate recognition domain-2 (CRD-2) heterologously expressed. This mAb recognizes a protein band of 250kDa by immunoprecipitation analysis and shows strong cross-reactivity with human and pig DEC-205. Furthermore, the hemagglutinin (HA) of avian influenza H5N2 virus was cloned and expressed using insect cell-baculovirus expression system. We chemically conjugated the anti-chicken DEC-205 antibody with the highly purified HA to direct the antigen to the dendritic cells and evaluate the immune response elicited in vivo by this conjugate. A single dose of chemical conjugate was sufficient to elicit a strong immune response in chickens as early as fourteen days after priming. In addition, the conjugate induced an earlier and higher response compared to unconjugated HA. These results suggest that the strategy described here has potential to be used in the future design and development of successful vaccines against different chicken infectious diseases with direct impact in biotechnology and veterinary fields. Copyright © 2016 Elsevier Ltd. All rights reserved.

New generation of oral mucosal vaccines targeting dendritic cells.

PubMed

Owen, Jennifer L; Sahay, Bikash; Mohamadzadeh, Mansour

2013-12-01

As most infectious organisms gain entry at mucosal surfaces, there is a great deal of interest in developing vaccines that elicit effective mucosal immune responses against pathogen challenge. Targeted vaccination is one of the most effective methods available to prevent and control infectious diseases. Mucosal vaccines can offer lower costs, better accessibility, needle free delivery, and a higher capacity for mass immunizations during pandemics. Both local mucosal immunity and robust systemic responses can be achieved through mucosal vaccination. Recent progress in understanding the molecular and cellular components of the mucosal immune system have allowed for the development of a novel mucosal vaccine platform utilizing specific dendritic cell-targeting peptides and orally administered lactobacilli to elicit efficient antigen specific immune responses against infections, including Bacillus anthracis in experimental models of disease. Copyright © 2013 Elsevier Ltd. All rights reserved.

Targeting Mycobacterium tuberculosis Antigens to Dendritic Cells via the DC-Specific-ICAM3-Grabbing-Nonintegrin Receptor Induces Strong T-Helper 1 Immune Responses

PubMed Central

Velasquez, Lis Noelia; Stüve, Philipp; Gentilini, Maria Virginia; Swallow, Maxine; Bartel, Judith; Lycke, Nils Yngve; Barkan, Daniel; Martina, Mariana; Lujan, Hugo D.; Kalay, Hakan; van Kooyk, Yvette; Sparwasser, Tim D.; Berod, Luciana

2018-01-01

Tuberculosis remains a major global health problem and efforts to develop a more effective vaccine have been unsuccessful so far. Targeting antigens (Ags) to dendritic cells (DCs) in vivo has emerged as a new promising vaccine strategy. In this approach, Ags are delivered directly to DCs via antibodies that bind to endocytic cell-surface receptors. Here, we explored DC-specific-ICAM3-grabbing-nonintegrin (DC-SIGN) targeting as a potential vaccine against tuberculosis. For this, we made use of the hSIGN mouse model that expresses human DC-SIGN under the control of the murine CD11c promoter. We show that in vitro and in vivo delivery of anti-DC-SIGN antibodies conjugated to Ag85B and peptide 25 of Ag85B in combination with anti-CD40, the fungal cell wall component zymosan, and the cholera toxin-derived fusion protein CTA1-DD induces strong Ag-specific CD4+ T-cell responses. Improved anti-mycobacterial immunity was accompanied by increased frequencies of Ag-specific IFN-γ+ IL-2+ TNF-α+ polyfunctional CD4+ T cells in vaccinated mice compared with controls. Taken together, in this study we provide the proof of concept that the human DC-SIGN receptor can be efficiently exploited for vaccine purposes to promote immunity against mycobacterial infections. PMID:29662482

The Innate and Adaptive Immune System as Targets for Biologic Therapies in Inflammatory Bowel Disease.

PubMed

Holleran, Grainne; Lopetuso, Loris; Petito, Valentina; Graziani, Cristina; Ianiro, Gianluca; McNamara, Deirdre; Gasbarrini, Antonio; Scaldaferri, Franco

2017-09-21

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition causing inflammation of gastrointestinal and systemic cells, with an increasing prevalence worldwide. Many factors are known to trigger and maintain inflammation in IBD including the innate and adaptive immune systems, genetics, the gastrointestinal microbiome and several environmental factors. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents. The initial focus of these agents was directed against the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) leading to dramatic changes in the disease course for a proportion of patients with IBD. However, more recently, it has been shown that a significant proportion of patients do not respond to anti-TNF-α directed therapies, leading a shift to other inflammatory pathways and targets, including those of both the innate and adaptive immune systems, and targets linking both systems including anti-leukocyte trafficking agents-integrins and adhesion molecules. This review briefly describes the molecular basis of immune based gastrointestinal inflammation in IBD, and then describes how several current and future biologic agents work to manipulate these pathways, and their clinical success to date.

The Innate and Adaptive Immune System as Targets for Biologic Therapies in Inflammatory Bowel Disease

PubMed Central

Holleran, Grainne; Lopetuso, Loris; Petito, Valentina; Graziani, Cristina; Ianiro, Gianluca; McNamara, Deirdre; Gasbarrini, Antonio; Scaldaferri, Franco

2017-01-01

Inflammatory bowel disease (IBD) is an immune-mediated inflammatory condition causing inflammation of gastrointestinal and systemic cells, with an increasing prevalence worldwide. Many factors are known to trigger and maintain inflammation in IBD including the innate and adaptive immune systems, genetics, the gastrointestinal microbiome and several environmental factors. Our knowledge of the involvement of the immune system in the pathophysiology of IBD has advanced rapidly over the last two decades, leading to the development of several immune-targeted treatments with a biological source, known as biologic agents. The initial focus of these agents was directed against the pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) leading to dramatic changes in the disease course for a proportion of patients with IBD. However, more recently, it has been shown that a significant proportion of patients do not respond to anti-TNF-α directed therapies, leading a shift to other inflammatory pathways and targets, including those of both the innate and adaptive immune systems, and targets linking both systems including anti-leukocyte trafficking agents-integrins and adhesion molecules. This review briefly describes the molecular basis of immune based gastrointestinal inflammation in IBD, and then describes how several current and future biologic agents work to manipulate these pathways, and their clinical success to date. PMID:28934123

Near infrared photoimmunotherapy rapidly elicits specific host immunity against cancer cells (Conference Presentation)

NASA Astrophysics Data System (ADS)

Kobayashi, Hisataka

2017-02-01

Near infrared photoimmunotherapy (NIR-PIT) is a new molecularly-targeted cancer photo-therapy based on conjugating a near infrared silica-phthalocyanine dye, IR700, to a monoclonal antibody (mAb) targeting cell-surface molecules. When exposed to NIR light, the conjugate induces a highly-selective necrotic/immunogenic cell death (ICD) only in target-positive, mAb-IR700-bound cancer cells. This cell death occurs as early as 1 minute after exposure to NIR light. Meanwhile, immediately adjacent target-negative cells are unharmed. Dynamic 3D-microscopy of live tumor cells undergoing NIR-PIT showed rapid swelling in treated cells immediately after light exposure, followed by irreversible morphologic changes such as bleb formation, and rupture of vesicles within several minutes. Furthermore, biological markers of ICD including relocation of HSP70/90 and calreticulin, and release of ATP and High Mobility Group Box 1 (HMGB1), were clearly detected immediately after NIR-PIT. When NIR-PIT was performed in a mixture of cancer cells and immature dendritic cells, maturation of immature dendritic cells was strongly induced rapidly after NIR-PIT. Alternatively, NIR-PIT can also target negative regulatory immune cells such as Treg only in the tumor bed. Treg targeting NIR-PIT against CD25 can deplete >80% of Treg in tumor bed within 20 min that induces activation of tumor cell-specific CD8+-T and NK cells within 1.5 hour, and then these activated cells killed cancer cells in local tumor within 1 day and also in distant tumors of the same cell origin within 2 days. In summary, cancer cell-targeting and immuno-suppressor cell-targeting NIR-PITs effectively induce innate and acquired immunity specifically against cancer cells growing in patients, respectively.

Hantavirus Gc induces long-term immune protection via LAMP-targeting DNA vaccine strategy.

PubMed

Jiang, Dong-Bo; Zhang, Jin-Peng; Cheng, Lin-Feng; Zhang, Guan-Wen; Li, Yun; Li, Zi-Chao; Lu, Zhen-Hua; Zhang, Zi-Xin; Lu, Yu-Chen; Zheng, Lian-He; Zhang, Fang-Lin; Yang, Kun

2018-02-01

Hemorrhagic fever with renal syndrome (HFRS) occurs widely throughout Eurasia. Unfortunately, there is no effective treatment, and prophylaxis remains the best option against the major pathogenic agent, hantaan virus (HTNV), which is an Old World hantavirus. However, the absence of cellular immune responses and immunological memory hampers acceptance of the current inactivated HFRS vaccine. Previous studies revealed that a lysosome-associated membrane protein 1 (LAMP1)-targeting strategy involving a DNA vaccine based on the HTNV glycoprotein Gn successfully conferred long-term immunity, and indicated that further research on Gc, another HTNV antigen, was warranted. Plasmids encoding Gc and lysosome-targeted Gc, designated pVAX-Gc and pVAX-LAMP/Gc, respectively, were constructed. Proteins of interest were identified by fluorescence microscopy following cell line transfection. Five groups of 20 female BALB/c mice were subjected to the following inoculations: inactivated HTNV vaccine, pVAX-LAMP/Gc, pVAX-Gc, and, as the negative controls, pVAX-LAMP or the blank vector pVAX1. Humoral and cellular immunity were assessed by enzyme-linked immunosorbent assays (ELISAs) and 15-mer peptide enzyme-linked immunospot (ELISpot) epitope mapping assays. Repeated immunization with pVAX-LAMP/Gc enhanced adaptive immune responses, as demonstrated by the specific and neutralizing antibody titers and increased IFN-γ production. The inactivated vaccine induced a comparable humoral reaction, but the negative controls only elicited insignificant responses. Using a mouse model of HTNV challenge, the in vivo protection conferred by the inactivated vaccine and Gc-based constructs (with/without LAMP recombination) was confirmed. Evidence of pan-epitope reactions highlighted the long-term cellular response to the LAMP-targeting strategy, and histological observations indicated the safety of the LAMP-targeting vaccines. The long-term protective immune responses induced by pVAX-LAMP/Gc may be

Targeting Antitumor Immune Response for Enhancing the Efficacy of Photodynamic Therapy of Cancer: Recent Advances and Future Perspectives

PubMed Central

2016-01-01

Photodynamic therapy (PDT) is a minimally invasive therapeutic strategy for cancer treatment, which can destroy local tumor cells and induce systemic antitumor immune response, whereas, focusing on improving direct cytotoxicity to tumor cells treated by PDT, there is growing interest in developing approaches to further explore the immune stimulatory properties of PDT. In this review we summarize the current knowledge of the innate and adaptive immune responses induced by PDT against tumors, providing evidence showing PDT facilitated-antitumor immunity. Various immunotherapeutic approaches on different cells are reviewed for their effectiveness in improving the treatment efficiency in concert with PDT. Future perspectives are discussed for further enhancing PDT efficiency via intracellular targetable drug delivery as well as optimized experimental model development associated with the study of antitumor immune response. PMID:27672421

Targeting the genital tract mucosa with a lipopeptide/recombinant adenovirus prime/boost vaccine induces potent and long-lasting CD8+ T cell immunity against herpes: importance of MyD88.

PubMed

Zhang, Xiuli; Dervillez, Xavier; Chentoufi, Aziz Alami; Badakhshan, Tina; Bettahi, Ilham; Benmohamed, Lbachir

2012-11-01

Targeting of the mucosal immune system of the genital tract with subunit vaccines has failed to induce potent and durable local CD8(+) T cell immunity, which is crucial for protection against many sexually transmitted viral pathogens, including HSV type 2 (HSV-2), which causes genital herpes. In this study, we aimed to investigate the potential of a novel lipopeptide/adenovirus type 5 (Lipo/rAdv5) prime/boost mucosal vaccine for induction of CD8(+) T cell immunity to protect the female genital tract from herpes. The lipopeptide vaccine and the rAdv5 vaccine express the immunodominant HSV-2 CD8(+) T cell epitope (gB(498-505)), and both were delivered intravaginally in the progesterone-induced B6 mouse model of genital herpes. Compared with mice immunized with the homologous lipopeptide/lipopeptide (Lipo/Lipo) vaccine, the Lipo/rAdv5 prime/boost immunized mice 1) developed potent and sustained HSV-specific CD8(+) T cells, detected in both the genital tract draining nodes and in the vaginal mucosa; 2) had significantly lower virus titers; 3) had decreased overt signs of genital herpes disease; and 4) did not succumb to lethal infection (p < 0.005) after intravaginal HSV-2 challenge. Polyfunctional CD8(+) T cells, producing IFN-γ, TNF-α, and IL-2 and exhibiting cytotoxic activity, were associated with protection (p < 0.005). The protective CD8(+) T cell response was significantly compromised in the absence of the adapter MyD88 (p = 0.0001). Taken together, these findings indicate that targeting of the vaginal mucosa with a Lipo/rAdv5 prime/boost vaccine elicits a potent, MyD88-dependent, and long-lasting mucosal CD8(+) T cell protective immunity against sexually transmitted herpes infection and disease.

An evolving new paradigm: endothelial cells--conditional innate immune cells.

PubMed

Mai, Jietang; Virtue, Anthony; Shen, Jerry; Wang, Hong; Yang, Xiao-Feng

2013-08-22

Endothelial cells (ECs) are a heterogeneous population that fulfills many physiological processes. ECs also actively participate in both innate and adaptive immune responses. ECs are one of the first cell types to detect foreign pathogens and endogenous metabolite-related danger signals in the bloodstream, in which ECs function as danger signal sensors. Treatment with lipopolysaccharide activates ECs, causing the production of pro-inflammatory cytokines and chemokines, which amplify the immune response by recruiting immune cells. Thus, ECs function as immune/inflammation effectors and immune cell mobilizers. ECs also induce cytokine production by immune cells, in which ECs function as immune regulators either by activating or suppressing immune cell function. In addition, under certain conditions, ECs can serve as antigen presenting cells (antigen presenters) by expressing both MHC I and II molecules and presenting endothelial antigens to T cells. These facts along with the new concept of endothelial plasticity suggest that ECs are dynamic cells that respond to extracellular environmental changes and play a meaningful role in immune system function. Based on these novel EC functions, we propose a new paradigm that ECs are conditional innate immune cells. This paradigm provides a novel insight into the functions of ECs in inflammatory/immune pathologies.

HIV-derived vectors for gene therapy targeting dendritic cells.

PubMed

Rossetti, Maura; Cavarelli, Mariangela; Gregori, Silvia; Scarlatti, Gabriella

2013-01-01

Human immunodeficiency virus type 1 (HIV-1)-derived lentiviral vectors (LV) have the potential to mediate stable therapeutic gene transfer. However, similarly to other viral vectors, their benefit is compromised by the induction of an immune response toward transgene-expressing cells that closely mimics antiviral immunity. LV share with the parental HIV the ability to activate dendritic cells (DC), while lack the peculiar ability of subverting DC functions, which is responsible for HIV immune escape. Understanding the interaction between LV and DC, with plasmacytoid and myeloid DC playing fundamental and distinct roles, has paved the way to novel approaches aimed at regulating transgene-specific immune responses. Thanks to the ability to target either DC subsets LV might be a powerful tool to induce immunity (i.e., gene therapy of cancer), cell death (i.e., in HIV/AIDS infection), or tolerance (i.e., gene therapy strategies for monogenic diseases). In this chapter, similarities and differences between the LV-mediated and HIV-mediated induction of immune responses, with specific focus on their interactions with DC, are discussed.

Imaging immune surveillance of individual natural killer cells confined in microwell arrays.

PubMed

Guldevall, Karolin; Vanherberghen, Bruno; Frisk, Thomas; Hurtig, Johan; Christakou, Athanasia E; Manneberg, Otto; Lindström, Sara; Andersson-Svahn, Helene; Wiklund, Martin; Önfelt, Björn

2010-11-12

New markers are constantly emerging that identify smaller and smaller subpopulations of immune cells. However, there is a growing awareness that even within very small populations, there is a marked functional heterogeneity and that measurements at the population level only gives an average estimate of the behaviour of that pool of cells. New techniques to analyze single immune cells over time are needed to overcome this limitation. For that purpose, we have designed and evaluated microwell array systems made from two materials, polydimethylsiloxane (PDMS) and silicon, for high-resolution imaging of individual natural killer (NK) cell responses. Both materials were suitable for short-term studies (<4 hours) but only silicon wells allowed long-term studies (several days). Time-lapse imaging of NK cell cytotoxicity in these microwell arrays revealed that roughly 30% of the target cells died much more rapidly than the rest upon NK cell encounter. This unexpected heterogeneity may reflect either separate mechanisms of killing or different killing efficiency by individual NK cells. Furthermore, we show that high-resolution imaging of inhibitory synapse formation, defined by clustering of MHC class I at the interface between NK and target cells, is possible in these microwells. We conclude that live cell imaging of NK-target cell interactions in multi-well microstructures are possible. The technique enables novel types of assays and allow data collection at a level of resolution not previously obtained. Furthermore, due to the large number of wells that can be simultaneously imaged, new statistical information is obtained that will lead to a better understanding of the function and regulation of the immune system at the single cell level.

Pros and Cons of Antigen-Presenting Cell Targeted Tumor Vaccines.

PubMed

Goyvaerts, Cleo; Breckpot, Karine

2015-01-01

In therapeutic antitumor vaccination, dendritic cells play the leading role since they decide if, how, when, and where a potent antitumor immune response will take place. Since the disentanglement of the complexity and merit of different antigen-presenting cell subtypes, antitumor immunotherapeutic research started to investigate the potential benefit of targeting these subtypes in situ. This review will discuss which antigen-presenting cell subtypes are at play and how they have been targeted and finally question the true meaning of targeting antitumor-based vaccines.

An Il12-Il2-Antibody Fusion Protein Targeting Hodgkin's Lymphoma Cells Potentiates Activation Of Nk And T Cells For An Anti-Tumor Attack

PubMed Central

Friedrichs, Björn; Heuser, Claudia; Guhlke, Stefan; Abken, Hinrich; Hombach, Andreas A.

2012-01-01

Successful immunotherapy of Hodgkin's disease is so far hampered by the striking unresponsiveness of lymphoma infiltrating immune cells. To mobilize both adoptive and innate immune cells for an anti-tumor attack we fused the pro-inflammatory cytokines IL2 and IL12 to an anti-CD30 scFv antibody in a dual cytokine fusion protein to accumulate both cytokines at the malignant CD30+ Hodgkin/Reed-Sternberg cells in the lymphoma lesion. The tumor-targeted IL12-IL2 fusion protein was superior in activating resting T cells to amplify and secrete pro-inflammatory cytokines compared to targeted IL2 or IL12 alone. NK cells were also activated by the dual cytokine protein to secrete IFN-γ and to lyse target cells. The tumor-targeted IL12-IL2, when applied by i.v. injection to immune-competent mice with established antigen-positive tumors, accumulated at the tumor site and induced tumor regression. Data demonstrate that simultaneous targeting of two cytokines in a spatial and temporal simultaneous fashion to pre-defined tissues is feasible by a dual-cytokine antibody fusion protein. In the case of IL12 and IL2, this produced superior anti-tumor efficacy implying the strategy to muster a broader immune cell response in the combat against cancer. PMID:23028547

Immune cell screening of a nanoparticle library improves atherosclerosis therapy

PubMed Central

Baxter, Samantha; Menon, Arjun; Alaarg, Amr; Sanchez-Gaytan, Brenda L.; Fay, Francois; Zhao, Yiming; Ouimet, Mireille; Braza, Mounia S.; Longo, Valerie A.; Abdel-Atti, Dalya; Duivenvoorden, Raphael; Calcagno, Claudia; Storm, Gert; Tsimikas, Sotirios; Moore, Kathryn J.; Swirski, Filip K.; Nahrendorf, Matthias; Fisher, Edward A.; Pérez-Medina, Carlos; Fayad, Zahi A.; Reiner, Thomas; Mulder, Willem J. M.

2016-01-01

Immunological complexity in atherosclerosis warrants targeted treatment of specific inflammatory cells that aggravate the disease. With the initiation of large phase III trials investigating immunomodulatory drugs for atherosclerosis, cardiovascular disease treatment enters a new era. We here propose a radically different approach: implementing and evaluating in vivo a combinatorial library of nanoparticles with distinct physiochemical properties and differential immune cell specificities. The library’s nanoparticles are based on endogenous high-density lipoprotein, which can preferentially deliver therapeutic compounds to pathological macrophages in atherosclerosis. Using the apolipoprotein E-deficient (Apoe−/−) mouse model of atherosclerosis, we quantitatively evaluated the library’s immune cell specificity by combining immunological techniques and in vivo positron emission tomography imaging. Based on this screen, we formulated a liver X receptor agonist (GW3965) and abolished its liver toxicity while still preserving its therapeutic function. Screening the immune cell specificity of nanoparticles can be used to develop tailored therapies for atherosclerosis and other inflammatory diseases. PMID:27791119

Immune selection of tumor cells in TCR β-chain transgenic mice.

PubMed

Silaeva, Yulia Yu; Grinenko, Tatyana S; Vagida, Murad S; Kalinina, Anastasia A; Khromykh, Ludmila M; Kazansky, Dmitry B

2014-10-01

The concept of immunological surveillance implies that immunogenic variants of tumor cells arising in the organism can be recognized by the immune system. Tumor progression is provided by somatic evolution of tumor cells under the pressure of the immune system. The loss of MHC Class I molecules on the surface of tumor cells is one of the most known outcomes of immune selection. This study developed a model of immune selection based on the immune response of TCR 1d1 single β-chain transgenic B10.D2(R101) (K(d)I(d)D(b)) mice to allogeneic EL4 (H-2(b)) thymoma cells. In wild-type B10.D2(R101) mice, immunization with EL4 cells induced a vigorous CTL response targeted to the H-2K(b) molecule and results in full rejection of the tumor cells. In contrast, transgenic mice developed a compromised proliferative response in mixed-lymphocyte response assays and were unable to reject transplanted allogeneic EL4 cells. During the immune response to EL4 cells, CD8(+) T-lymphocytes with endogenous β-chains accumulated predominantly in the spleen of transgenic mice and only a small part of the T-lymphocytes expressing transgenic β-chains became CD8(+)CD44(+)CD62L(-) effectors. Then, instead of a full elimination of tumor cells as in wild-type mice, a reproducible prolonged equilibrium phase and subsequent escape was observed in transgenic mice that resulted in death of 90% of the mice in 40-60 days after grafting. Prolonged exposure of tumor cells to the pressure of the immune system in transgenic mice in vivo resulted in a stable loss of H-2K(b) molecules on the EL4 cell surface. Genetic manipulation of the T-lymphocyte repertoire was sufficient to reproduce the classic pattern of interactions between tumor cells and the immune system, usually observed in reliable syngeneic models of anti-tumor immunity. This newly-developed model could be used in further studies of immunoregulatory circuits common for transplantational and anti-tumor immune responses.

Immune modulation by genetic modification of dendritic cells with lentiviral vectors.

PubMed

Liechtenstein, Therese; Perez-Janices, Noemi; Bricogne, Christopher; Lanna, Alessio; Dufait, Inès; Goyvaerts, Cleo; Laranga, Roberta; Padella, Antonella; Arce, Frederick; Baratchian, Mehdi; Ramirez, Natalia; Lopez, Natalia; Kochan, Grazyna; Blanco-Luquin, Idoia; Guerrero-Setas, David; Breckpot, Karine; Escors, David

2013-09-01

Our work over the past eight years has focused on the use of HIV-1 lentiviral vectors (lentivectors) for the genetic modification of dendritic cells (DCs) to control their functions in immune modulation. DCs are key professional antigen presenting cells which regulate the activity of most effector immune cells, including T, B and NK cells. Their genetic modification provides the means for the development of targeted therapies towards cancer and autoimmune disease. We have been modulating with lentivectors the activity of intracellular signalling pathways and co-stimulation during antigen presentation to T cells, to fine-tune the type and strength of the immune response. In the course of our research, we have found unexpected results such as the surprising immunosuppressive role of anti-viral signalling pathways, and the close link between negative co-stimulation in the immunological synapse and T cell receptor trafficking. Here we review our major findings and put them into context with other published work. Copyright © 2013 Elsevier B.V. All rights reserved.

MicroRNA-466l inhibits antiviral innate immune response by targeting interferon-alpha

PubMed Central

Li, Yingke; Fan, Xiaohua; He, Xingying; Sun, Haijing; Zou, Zui; Yuan, Hongbin; Xu, Haitao; Wang, Chengcai; Shi, Xueyin

2012-01-01

Effective recognition of viral infections and subsequent triggering of antiviral innate immune responses are essential for the host antiviral defense, which is tightly regulated by multiple regulators, including microRNAs (miRNAs). A previous study showed that miR-466l upregulates IL-10 expression in macrophages by antagonizing RNA-binding protein tristetraprolin-mediated IL-10 mRNA degradation. However, the ability of miR-466l to regulate antiviral immune responses remains unknown. Here, we found that interferon-alpha (IFN-α) expression was repressed in Sendai virus (SeV)- and vesicular stomatitis virus (VSV)-infected macrophages and in dendritic cells transfected with miR-466l expression. Moreover, multiple IFN-α species can be directly targeted by miR-466l through their 3′ untranslated region (3′UTR). This study has demonstrated that miR-466l could directly target IFN-α expression to inhibit host antiviral innate immune response. PMID:23042536

Adoptive immunotherapy for B-cell malignancies with autologous chimeric antigen receptor modified tumor targeted T cells.

PubMed

Park, Jae H; Brentjens, Renier J

2010-04-01

Chemotherapy-resistant B-cell hematologic malignancies may be cured with allogeneic hematopoietic stem cell transplantation (HSCT), demonstrating the potential susceptibility of these tumors to donor T-cell mediated immune responses. However, high rates of transplant-related morbidity and mortality limit this approach. For this reason, there is an urgent need for less-toxic forms of immune-based cellular therapy to treat these malignancies. Adoptive transfer of autologous T cells genetically modified to express chimeric antigen receptors (CARs) targeted to specific tumor-associated antigens represents an attractive means of overcoming the limitations of conventional HSCT. To this end, investigators have generated CARs targeted to various antigens expressed by B-cell malignancies, optimized the design of these CARs to enhance receptor mediated T cell signaling, and demonstrated significant anti-tumor efficacy of the resulting CAR modified T cells both in vitro and in vivo mouse tumor models. These encouraging preclinical data have justified the translation of this approach to the clinical setting with currently 12 open clinical trials and one completed clinical trial treating various B-cell malignancies utilizing CAR modified T cells targeted to either the CD19 or CD20 B-cell specific antigens.

The Mycobacterium tuberculosis cell-surface glycoprotein apa as a potential adhesin to colonize target cells via the innate immune system pulmonary C-type lectin surfactant protein A.

PubMed

Ragas, Aude; Roussel, Lucie; Puzo, Germain; Rivière, Michel

2007-02-23

Tuberculosis is still a major health problem, and understanding the mechanism by which Mycobacterium tuberculosis (Mtb) invades and colonizes its host target cells remains an important issue for the control of infection. The innate immune system C-type lectins (C-TLs), including the human pulmonary surfactant protein A (PSP-A), have been recently identified as determinant players in the early recognition of the invading pathogen and in mounting the host defense response. Although the antigenic lipoglycan mannosylated lipoarabinomannan is currently considered to be the major C-TL target on the mycobacterial surface, the recognition by some C-TLs of the only mycobacterial species composing the "Mtb complex" indicates that mannosylated lipoarabinomannan cannot account alone for this specificity. Thus, we searched for the mycobacterial molecules targeted by human PSP-A, focusing our attention on the Mtb surface glycoproteins. We developed an original functional proteomic approach based on a lectin blot assay using crude human bronchoalveolar lavage fluid as a source of physiological PSP-A. Combined with selective cell-surface protein extraction and mass spectrometry peptide mapping, this strategy allowed us to identify the Apa (alanine- and proline-rich antigenic) glycoprotein as new potential target for PSP-A. This result was supported by direct binding of PSP-A to purified Apa. Moreover, EDTA addition or deglycosylation of purified Apa samples completely abolished the interaction, demonstrating that the interaction is calcium- and mannose-dependent, as expected. Finally, we provide convincing evidence that Apa, formerly considered as mainly secreted, is associated with the cell wall for a sufficiently long time to aid in the attachment of PSP-A. Because, to date, Apa seems to be restricted to the Mtb complex strains, we propose that it may account for the selective recognition of those strains by PSP-A and other immune system C-TLs containing homologous functional

Curcumin reverses T cell-mediated adaptive immune dysfunctions in tumor-bearing hosts.

PubMed

Bhattacharyya, Sankar; Md Sakib Hossain, Dewan; Mohanty, Suchismita; Sankar Sen, Gouri; Chattopadhyay, Sreya; Banerjee, Shuvomoy; Chakraborty, Juni; Das, Kaushik; Sarkar, Diptendra; Das, Tanya; Sa, Gaurisankar

2010-07-01

Immune dysfunction is well documented during tumor progression and likely contributes to tumor immune evasion. CD8(+) cytotoxic T lymphocytes (CTLs) are involved in antigen-specific tumor destruction and CD4(+) T cells are essential for helping this CD8(+) T cell-dependent tumor eradication. Tumors often target and inhibit T-cell function to escape from immune surveillance. This dysfunction includes loss of effector and memory T cells, bias towards type 2 cytokines and expansion of T regulatory (Treg) cells. Curcumin has previously been shown to have antitumor activity and some research has addressed the immunoprotective potential of this plant-derived polyphenol in tumor-bearing hosts. Here we examined the role of curcumin in the prevention of tumor-induced dysfunction of T cell-based immune responses. We observed severe loss of both effector and memory T-cell populations, downregulation of type 1 and upregulation of type 2 immune responses and decreased proliferation of effector T cells in the presence of tumors. Curcumin, in turn, prevented this loss of T cells, expanded central memory T cell (T(CM))/effector memory T cell (T(EM)) populations, reversed the type 2 immune bias and attenuated the tumor-induced inhibition of T-cell proliferation in tumor-bearing hosts. Further investigation revealed that tumor burden upregulated Treg cell populations and stimulated the production of the immunosuppressive cytokines transforming growth factor (TGF)-beta and IL-10 in these cells. Curcumin, however, inhibited the suppressive activity of Treg cells by downregulating the production of TGF-beta and IL-10 in these cells. More importantly, curcumin treatment enhanced the ability of effector T cells to kill cancer cells. Overall, our observations suggest that the unique properties of curcumin may be exploited for successful attenuation of tumor-induced suppression of cell-mediated immune responses.

Reproductive Toxicity of T Cells in Early Life: Abnormal Immune Development and Postnatal Diseases.

PubMed

Liu, Han-Xiao; Jiang, Aifang; Chen, Ting; Qu, Wen; Yan, Hui-Yi; Ping, Jie

2017-01-01

Immunity is a balanced status with adequate biological defenses to recognize and fight "non-self", as well as adequate tolerance to recognize "self". To maintain this immune homeostasis, a well-organized T cell immune network is required, which in part depends on the well-controlled development of alternative effector T cells, with different cytokine repertoires. Recent researches have pointed that developing fetal T cells network is a remarkably sensitive toxicological target for adverse factors in early life. Epidemiological and experimental studies showed an inseparable relationship between T cell developmental toxicity and immune diseases in adults. Considering that the inflammatory and immune disorders have become a growing health problem worldwide, increasing attention is now being paid to the T cell developmental toxicity. We propose that adverse factors may have programming effects on the crucial functions of immune system during early life which is critical for fetal T cell development and the establishment of the distinct T cell repertoires balance. The permanently disturbed intrathymic or peripheral T cell development may in turn lead to the immune disorders in later life. In this manuscript, we reviewed how adverse factors affected T cell development in early-life with the consequence of the immune dysfunction and immune diseases, and further elucidate the mechanisms. These mechanisms will be helpful in prevention and treatment of the increased prevalence of immune diseases by interfering those pathways. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Lysosomal Rerouting of Hsp70 Trafficking as a Potential Immune Activating Tool for Targeting Melanoma

PubMed Central

Juhász, Kata; Thuenauer, Roland; Spachinger, Andrea; Duda, Ernő; Horváth, Ibolya; Vígh, László; Sonnleitner, Alois; Balogi, Zsolt

2013-01-01

Tumor specific cell surface localization and release of the stress inducible heat shock protein 70 (Hsp70) stimulate the immune system against cancer cells. A key immune stimulatory function of tumor-derived Hsp70 has been exemplified with the murine melanoma cell model, B16 overexpressing exogenous Hsp70. Despite the therapeutic potential mechanism of Hsp70 transport to the surface and release remained poorly understood. We investigated principles of Hsp70 trafficking in B16 melanoma cells with low and high level of Hsp70. In cells with low level of Hsp70 apparent trafficking of Hsp70 was mediated by endosomes. Excess Hsp70 triggered a series of changes such as a switch of Hsp70 trafficking from endosomes to lysosomes and a concomitant accumulation of Hsp70 in lysosomes. Moreover, lysosomal rerouting resulted in an elevated concentration of surface Hsp70 and enabled active release of Hsp70. In fact, hyperthermia, a clinically applicable approach triggered immediate active lysosomal release of soluble Hsp70 from cells with excess Hsp70. Furthermore, excess Hsp70 enabled targeting of internalized surface Hsp70 to lysosomes, allowing in turn heat-induced secretion of surface Hsp70. Altogether, we show that excess Hsp70 expressed in B16 melanoma cells diverts Hsp70 trafficking from endosomes to lysosomes, thereby supporting its surface localization and lysosomal release. Controlled excess-induced lysosomal rerouting and secretion of Hsp70 is proposed as a promising tool to stimulate anti-tumor immunity targeting melanoma. PMID:22920897

A distinct plasmablast and naïve B-cell phenotype in primary immune thrombocytopenia

PubMed Central

Flint, Shaun M.; Gibson, Adele; Lucas, Geoff; Nandigam, Raghava; Taylor, Louise; Provan, Drew; Newland, Adrian C.; Savage, Caroline O.; Henderson, Robert B.

2016-01-01

Primary immune thrombocytopenia is an autoimmune disorder in which platelet destruction is a consequence of both B- and T-cell dysregulation. Flow cytometry was used to further characterize the B- and T-cell compartments in a cross-sectional cohort of 26 immune thrombocytopenia patients including antiplatelet antibody positive (n=14) and negative (n=12) patients exposed to a range of therapies, and a cohort of matched healthy volunteers. Markers for B-cell activating factor and its receptors, relevant B-cell activation markers (CD95 and CD21) and markers for CD4+ T-cell subsets, including circulating T-follicular helper-like cells, were included. Our results indicate that an expanded population of CD95+ naïve B cells correlated with disease activity in immune thrombocytopenia patients regardless of treatment status. A population of CD21-naïve B cells was specifically expanded in autoantibody-positive immune thrombocytopenia patients. Furthermore, the B-cell maturation antigen, a receptor for B-cell activating factor, was consistently and strongly up-regulated on plasmablasts from immune thrombocytopenia patients. These observations have parallels in other autoantibody-mediated diseases and suggest that loss of peripheral tolerance in naïve B cells may be an important component of immune thrombocytopenia pathogenesis. Moreover, the B-cell maturation antigen represents a potential target for plasma cell directed therapies in immune thrombocytopenia. PMID:26969086

A distinct plasmablast and naïve B-cell phenotype in primary immune thrombocytopenia.

PubMed

Flint, Shaun M; Gibson, Adele; Lucas, Geoff; Nandigam, Raghava; Taylor, Louise; Provan, Drew; Newland, Adrian C; Savage, Caroline O; Henderson, Robert B

2016-06-01

Primary immune thrombocytopenia is an autoimmune disorder in which platelet destruction is a consequence of both B- and T-cell dysregulation. Flow cytometry was used to further characterize the B- and T-cell compartments in a cross-sectional cohort of 26 immune thrombocytopenia patients including antiplatelet antibody positive (n=14) and negative (n=12) patients exposed to a range of therapies, and a cohort of matched healthy volunteers. Markers for B-cell activating factor and its receptors, relevant B-cell activation markers (CD95 and CD21) and markers for CD4(+) T-cell subsets, including circulating T-follicular helper-like cells, were included. Our results indicate that an expanded population of CD95(+) naïve B cells correlated with disease activity in immune thrombocytopenia patients regardless of treatment status. A population of CD21-naïve B cells was specifically expanded in autoantibody-positive immune thrombocytopenia patients. Furthermore, the B-cell maturation antigen, a receptor for B-cell activating factor, was consistently and strongly up-regulated on plasmablasts from immune thrombocytopenia patients. These observations have parallels in other autoantibody-mediated diseases and suggest that loss of peripheral tolerance in naïve B cells may be an important component of immune thrombocytopenia pathogenesis. Moreover, the B-cell maturation antigen represents a potential target for plasma cell directed therapies in immune thrombocytopenia. Copyright© Ferrata Storti Foundation.

MHC class-I associated phosphopeptides are the targets of memory-like immunity in leukemia

PubMed Central

Cobbold, Mark; De La Peña, Hugo; Norris, Andrew; Polefrone, Joy; Qian, Jie; English, A. Michelle; Cummings, Kara; Penny, Sarah; Turner, James E.; Cottine, Jennifer; Abelin, Jennifer G; Malaker, Stacy A; Zarling, Angela L; Huang, Hsing-Wen; Goodyear, Oliver; Freeman, Sylvie; Shabanowitz, Jeffrey; Pratt, Guy; Craddock, Charles; Williams, Michael E; Hunt, Donald F; Engelhard, Victor H

2014-01-01

Deregulation of signaling pathways involving phosphorylation is a hallmark of malignant transformation. Degradation of phosphoproteins generates cancer-specific phosphopeptides that are associated with MHC-I and II molecules and recognized by T-cells. We identified 95 phosphopeptides presented on the surface of primary hematological tumors and normal tissues, including 61 that were tumor-specific. Phosphopeptides were more prevalent on more aggressive and malignant samples. CD8 T-cell lines specific for these phosphopeptides recognized and killed both leukemia cell lines and HLA-matched primary leukemia cells ex vivo. Healthy individuals showed surprisingly high levels of CD8 T-cell responses against many of these phosphopeptides within the circulating memory compartment. This immunity was significantly reduced or absent in some leukemia patients, which correlated with clinical outcome, and was restored following allogeneic stem cell transplantation. These results suggest that phosphopeptides may be targets of cancer immune surveillance in humans, and point to their importance for development of vaccine-based and T-cell adoptive transfer immunotherapies.. PMID:24048523

Dendritic Cells and Innate Immunity in Kidney Transplantation

PubMed Central

Zhuang, Quan; Lakkis, Fadi G.

2015-01-01

Summary This review summarizes emerging concepts related to the roles of dendritic cells and innate immunity in organ transplant rejection. First, it highlights the primary role that recipient, rather than donor, dendritic cells have in rejection and reviews their origin and function in the transplanted kidney. Second, it introduces the novel concept that recognition of allogeneic non-self by host monocytes (referred to here as innate allorecognition) is necessary for initiating rejection by inducing monocyte differentiation into mature, antigen-presenting dendritic cells. Both concepts provide opportunities for preventing rejection by targeting monocytes or dendritic cells. PMID:25629552

Rational design of nanoparticles towards targeting antigen-presenting cells and improved T cell priming.

PubMed

Zupančič, Eva; Curato, Caterina; Paisana, Maria; Rodrigues, Catarina; Porat, Ziv; Viana, Ana S; Afonso, Carlos A M; Pinto, João; Gaspar, Rogério; Moreira, João N; Satchi-Fainaro, Ronit; Jung, Steffen; Florindo, Helena F

2017-07-28

Vaccination is a promising strategy to trigger and boost immune responses against cancer or infectious disease. We have designed, synthesized and characterized aliphatic-polyester (poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NP) to investigate how the nature of protein association (adsorbed versus entrapped) and polymer/surfactant concentrations impact on the generation and modulation of antigen-specific immune responses. The ability of the NP formulations to target dendritic cells (DC), be internalized and activate the T cells was characterized and optimized in vitro and in vivo using markers of DC activation and co-stimulatory molecules. Ovalbumin (OVA) was used as a model antigen in combination with the engraftment of CD4 + and CD8 + T cells, carrying a transgenic OVA-responding T cell receptor (TCR), to trace and characterize the activation of antigen-specific CD4 + and CD8 + lymph node T cells upon NP vaccination. Accordingly, the phenotype and frequency of immune cell stimulation induced by the NP loaded with OVA, isolated or in combination with synthetic unmethylated cytosine-phosphate-guanine (CpG) oligodeoxynucleotide (ODN) motifs, were characterized. DC-NP interactions increased with incubation time, presenting internalization values between 50 and 60% and 30-40%, in vitro and in vivo, respectively. Interestingly, animal immunization with antigen-adsorbed NP up-regulated major histocompatibility complex (MHC) class II (MHCII), while NP entrapping the antigen up-regulated MHCI, suggesting a more efficient cross-presentation. On the other hand, rather surprisingly, the surfactant used in the NP formulation had a major impact on the activation of antigen presenting cells (APC). In fact, DC collected from lymph nodes of animals immunized with NP prepared using poly(vinil alcohol) (PVA), as a surfactant, expressed significantly higher levels of CD86, MHCI and MHCII. In addition, those NP prepared with PVA and co-entrapping OVA and the toll

Targeting Tumor-Associated Macrophages as a Potential Strategy to Enhance the Response to Immune Checkpoint Inhibitors.

PubMed

Cassetta, Luca; Kitamura, Takanori

2018-01-01

Inhibition of immune checkpoint pathways in CD8 + T cell is a promising therapeutic strategy for the treatment of solid tumors that has shown significant anti-tumor effects and is now approved by the FDA to treat patients with melanoma and lung cancer. However the response to this therapy is limited to a certain fraction of patients and tumor types, for reasons still unknown. To ensure success of this treatment, CD8 + T cells, the main target of the checkpoint inhibitors, should exert full cytotoxicity against tumor cells. However recent studies show that tumor-associated macrophages (TAM) can impede this process by different mechanisms. In this mini-review we will summarize recent studies showing the effect of TAM targeting on immune checkpoint inhibitors efficacy. We will also discuss on the limitations of the current strategies as well on the future scientific challenges for the progress of the tumor immunology field.

Interactions between MSCs and Immune Cells: Implications for Bone Healing

PubMed Central

Kovach, Tracy K.; Dighe, Abhijit S.; Lobo, Peter I.; Cui, Quanjun

2015-01-01

It is estimated that, of the 7.9 million fractures sustained in the United States each year, 5% to 20% result in delayed or impaired healing requiring therapeutic intervention. Following fracture injury, there is an initial inflammatory response that plays a crucial role in bone healing; however, prolonged inflammation is inhibitory for fracture repair. The precise spatial and temporal impact of immune cells and their cytokines on fracture healing remains obscure. Some cytokines are reported to be proosteogenic while others inhibit bone healing. Cell-based therapy utilizing mesenchymal stromal cells (MSCs) is an attractive option for augmenting the fracture repair process. Osteoprogenitor MSCs not only differentiate into bone, but they also exert modulatory effects on immune cells via a variety of mechanisms. In this paper, we review the current literature on both in vitro and in vivo studies on the role of the immune system in fracture repair, the use of MSCs in the enhancement of fracture healing, and interactions between MSCs and immune cells. Insight into this paradigm can provide valuable clues in identifying cellular and noncellular targets that can potentially be modulated to enhance both natural bone healing and bone repair augmented by the exogenous addition of MSCs. PMID:26000315

Induction of cell-mediated immunity against B16-BL6 melanoma in mice vaccinated with cells modified by hydrostatic pressure and chemical crosslinking.

PubMed

Eisenthal, A; Ramakrishna, V; Skornick, Y; Shinitzky, M

1993-05-01

In the preceding paper we have demonstrated an increase in presentation of both major histocompatibility complex antigens (MHC) and a tumor-associated antigen of the weakly immunogenic B16 melanoma by a straight-forward technique. The method consists in modulating the tumor cell membrane by hydrostatic pressure and simultaneous chemical crosslinking of the cell-surface proteins. In B16-BL6 melanoma, the induced antigenic modulation was found to persist for over 48 h, which permitted the evaluation of the ability of modified B16-BL6 cells to induce immunity against unmodified B16-BL6 cells. In the present study, we have shown that a significant systemic immunity was induced only in mice that were immunized with modified B16-BL6 melanoma cells, whereas immunization with unmodified B16-BL6 cells had only a marginal effect when compared to the results in control sham-immunized mice. The induced immunity was specific since a single immunization affected the growth of B16-BL6 tumors but had no effect on MCA 106, an antigenically unrelated tumor. The addition of interleukin-2 to the immunization regimen had no effect on the antitumor responses induced by the modified B16-BL6 cells. The cell-mediated immunity conferred by immunization with treated B16-BL6 cells was confirmed in experiments in vitro where splenocytes from immunized mice could be sensitized to proliferate by the presence of B16-BL6 cells. In addition, the altered antigenicity of these melanoma cells appeared to correlate with their increased susceptibility to specific effectors. Thus, 51Cr-labeled B16-BL6 target cells, modified by pressure and crosslinking, in comparison to control labeled target cells, were lysed in much greater numbers by effectors such as lymphokine-activated killer cells and allogeneic cytotoxic lymphocytes (anti-H-2b), while such cells remained resistant to lysis by natural killer cells. Our findings indicate that the physical and chemical modifications of the tumor cells that are

Inverse targeting —An effective immunization strategy

NASA Astrophysics Data System (ADS)

Schneider, C. M.; Mihaljev, T.; Herrmann, H. J.

2012-05-01

We propose a new method to immunize populations or computer networks against epidemics which is more efficient than any continuous immunization method considered before. The novelty of our method resides in the way of determining the immunization targets. First we identify those individuals or computers that contribute the least to the disease spreading measured through their contribution to the size of the largest connected cluster in the social or a computer network. The immunization process follows the list of identified individuals or computers in inverse order, immunizing first those which are most relevant for the epidemic spreading. We have applied our immunization strategy to several model networks and two real networks, the Internet and the collaboration network of high-energy physicists. We find that our new immunization strategy is in the case of model networks up to 14%, and for real networks up to 33% more efficient than immunizing dynamically the most connected nodes in a network. Our strategy is also numerically efficient and can therefore be applied to large systems.

The regulation of immune cells by Lactobacilli: a potential therapeutic target for anti-atherosclerosis therapy

PubMed Central

Ding, Ya-Hui; Qian, Lin-Yan; Pang, Jie; Lin, Jing-Yang; Xu, Qiang; Wang, Li-Hong; Huang, Dong-Sheng; Zou, Hai

2017-01-01

Atherosclerosis is an inflammatory disease regulated by several immune cells including lymphocytes, macrophages and dendritic cells. Gut probiotic bacteria like Lactobacilli have been shown immunomodificatory effects in the progression of atherogenesis. Some Lactobacillus stains can upregulate the activity of regulatory T-lymphocytes, suppress T-lymphocyte helper (Th) cells Th1, Th17, alter the Th1/Th2 ratio, influence the subsets ratio of M1/M2 macrophages, inhibit foam cell formation by suppressing macrophage phagocytosis of oxidized low-density lipoprotein, block the activation of the immune system with dendritic cells, which are expected to suppress the atherosclerosis-related inflammation. However, various strains can have various effects on inflammation. Some other Lactobacillus strains were found have potential pro-atherogenic effect through promote Th1 cell activity, increase pro-inflammatory cytokines levels as well as decrease anti-inflammatory cytokines levels. Thus, identifying the appropriate strains is essential to the therapeutic potential of Lactobacilli as an anti-atherosclerotic therapy. PMID:28938693

Antibody-targeted interleukin 2 stimulates T-cell killing of autologous tumor cells.

PubMed Central

Gillies, S D; Reilly, E B; Lo, K M; Reisfeld, R A

1992-01-01

A genetically engineered fusion protein consisting of a chimeric anti-ganglioside GD2 antibody (ch14.18) and interleukin 2 (IL2) was tested for its ability to enhance the killing of autologous GD2-expressing melanoma target cells by a tumor-infiltrating lymphocyte line (660 TIL). The fusion of IL2 to the carboxyl terminus of the immunoglobulin heavy chain did not reduce IL2 activity as measured in a standard proliferation assay using either mouse or human T-cell lines. Antigen-binding activity was greater than that of the native chimeric antibody. The ability of resting 660 TIL cells to kill their autologous GD2-positive target cells was enhanced if the target cells were first coated with the fusion protein. This stimulation of killing was greater than that of uncoated cells in the presence of equivalent or higher concentrations of free IL2. Such antibody-cytokine fusion proteins may prove useful in targeting the biological effect of IL2 and other cytokines to tumor cells and in this way stimulate their immune destruction. Images PMID:1741398

TNF-induced target cell killing by CTL activated through cross-presentation.

PubMed

Wohlleber, Dirk; Kashkar, Hamid; Gärtner, Katja; Frings, Marianne K; Odenthal, Margarete; Hegenbarth, Silke; Börner, Carolin; Arnold, Bernd; Hämmerling, Günter; Nieswandt, Bernd; van Rooijen, Nico; Limmer, Andreas; Cederbrant, Karin; Heikenwalder, Mathias; Pasparakis, Manolis; Protzer, Ulrike; Dienes, Hans-Peter; Kurts, Christian; Krönke, Martin; Knolle, Percy A

2012-09-27

Viruses can escape cytotoxic T cell (CTL) immunity by avoiding presentation of viral components via endogenous MHC class I antigen presentation in infected cells. Cross-priming of viral antigens circumvents such immune escape by allowing noninfected dendritic cells to activate virus-specific CTLs, but they remain ineffective against infected cells in which immune escape is functional. Here, we show that cross-presentation of antigen released from adenovirus-infected hepatocytes by liver sinusoidal endothelial cells stimulated cross-primed effector CTLs to release tumor necrosis factor (TNF), which killed virus-infected hepatocytes through caspase activation. TNF receptor signaling specifically eliminated infected hepatocytes that showed impaired anti-apoptotic defense. Thus, CTL immune surveillance against infection relies on two similarly important but distinct effector functions that are both MHC restricted, requiring either direct antigen recognition on target cells and canonical CTL effector function or cross-presentation and a noncanonical effector function mediated by TNF. Copyright © 2012 The Authors. Published by Elsevier Inc. All rights reserved.

An evolving new paradigm: endothelial cells – conditional innate immune cells

PubMed Central

2013-01-01

Endothelial cells (ECs) are a heterogeneous population that fulfills many physiological processes. ECs also actively participate in both innate and adaptive immune responses. ECs are one of the first cell types to detect foreign pathogens and endogenous metabolite-related danger signals in the bloodstream, in which ECs function as danger signal sensors. Treatment with lipopolysaccharide activates ECs, causing the production of pro-inflammatory cytokines and chemokines, which amplify the immune response by recruiting immune cells. Thus, ECs function as immune/inflammation effectors and immune cell mobilizers. ECs also induce cytokine production by immune cells, in which ECs function as immune regulators either by activating or suppressing immune cell function. In addition, under certain conditions, ECs can serve as antigen presenting cells (antigen presenters) by expressing both MHC I and II molecules and presenting endothelial antigens to T cells. These facts along with the new concept of endothelial plasticity suggest that ECs are dynamic cells that respond to extracellular environmental changes and play a meaningful role in immune system function. Based on these novel EC functions, we propose a new paradigm that ECs are conditional innate immune cells. This paradigm provides a novel insight into the functions of ECs in inflammatory/immune pathologies. PMID:23965413

PD-L1 expression on immune cells is a favorable prognostic factor for vulvar squamous cell carcinoma patients.

PubMed

Sznurkowski, Jacek J; Żawrocki, Anton; Sznurkowska, Katarzyna; Pęksa, Rafał; Biernat, Wojciech

2017-10-27

Anti-immune programmed death-ligand 1 (PD-L1) pathway is used by the tumor to overcome immune system and serves as immunotherapy target in various malignancies. To investigate the expression of PD-L1 in vulvar squamous cell carcinoma (vSCC) and to assess it's clinicopathological and prognostic significance. Immunohistochemical PD-L1 expression was evaluated in 84 vSCCs with previously defined status of p16 and DNA-HPV, infiltration of immune cells: CD8+, CD4+, FOXP3+, CD56+, CD68+, and GZB+ cells. PD-L1 positivity was defined as ≥5% of PD-L1-positive cells. Survival analyses included the Kaplan-Meier method, log-rank test and Cox proportional hazards model. PD-L1 expression was detected on cancer and peritumoral immune cells. PD-L1-positivity of cancer nests (27/84, 32.1%) was correlated with higher infiltration of CD4+ (p=0.037), CD8+ (p=0.02), FOXP3+ (p=0.007), CD68+ (p=0.021) cells, while PD-L1 positivity of peritumoral immune cells (51/84, 60.7%) was correlated with higher infiltration of intraepithelial FOXP3+ cells only (p=0.037).PD-L1-positivity of cancer cells but not immune cells, was more frequently observed in p16-negative tumors (p=0.004). High-risk HPV-status did not correlate with the PD-L1 status of cancer and immune cells (p=1.000) and (p=1.000) respectively). Median follow up was 89.20 months (range 1.7-189.5). PD-L1 positivity of peritumoral immune cells was found to be an independent favorable prognostic factor for OS. Conclusion: This study highlights the importance of comprehensive PD-L1 assessment in both cancer and immune cells. PD-L1 expression on peritumoral immune cells seems to be an additional prognostic factor in vSCC patients and may influence the results by anti-PD-L1 treatment.

PD-L1 expression on immune cells is a favorable prognostic factor for vulvar squamous cell carcinoma patients

PubMed Central

Sznurkowski, Jacek J.; Żawrocki, Anton; Sznurkowska, Katarzyna; Pęksa, Rafał; Biernat, Wojciech

2017-01-01

Background Anti-immune programmed death-ligand 1 (PD-L1) pathway is used by the tumor to overcome immune system and serves as immunotherapy target in various malignancies. Aim To investigate the expression of PD-L1 in vulvar squamous cell carcinoma (vSCC) and to assess it's clinicopathological and prognostic significance. Methods Immunohistochemical PD-L1 expression was evaluated in 84 vSCCs with previously defined status of p16 and DNA-HPV, infiltration of immune cells: CD8+, CD4+, FOXP3+, CD56+, CD68+, and GZB+ cells. PD-L1 positivity was defined as ≥5% of PD-L1-positive cells. Survival analyses included the Kaplan–Meier method, log-rank test and Cox proportional hazards model. Results PD-L1 expression was detected on cancer and peritumoral immune cells. PD-L1-positivity of cancer nests (27/84, 32.1%) was correlated with higher infiltration of CD4+ (p=0.037), CD8+ (p=0.02), FOXP3+ (p=0.007), CD68+ (p=0.021) cells, while PD-L1 positivity of peritumoral immune cells (51/84, 60.7%) was correlated with higher infiltration of intraepithelial FOXP3+ cells only (p=0.037). PD-L1-positivity of cancer cells but not immune cells, was more frequently observed in p16-negative tumors (p=0.004). High-risk HPV-status did not correlate with the PD-L1 status of cancer and immune cells (p=1.000) and (p=1.000) respectively). Median follow up was 89.20 months (range 1.7-189.5). PD-L1 positivity of peritumoral immune cells was found to be an independent favorable prognostic factor for OS. Conclusion: This study highlights the importance of comprehensive PD-L1 assessment in both cancer and immune cells. PD-L1 expression on peritumoral immune cells seems to be an additional prognostic factor in vSCC patients and may influence the results by anti-PD-L1 treatment. PMID:29163797

Dynamic Fungal Cell Wall Architecture in Stress Adaptation and Immune Evasion.

PubMed

Hopke, Alex; Brown, Alistair J P; Hall, Rebecca A; Wheeler, Robert T

2018-04-01

Deadly infections from opportunistic fungi have risen in frequency, largely because of the at-risk immunocompromised population created by advances in modern medicine and the HIV/AIDS pandemic. This review focuses on dynamics of the fungal polysaccharide cell wall, which plays an outsized role in fungal pathogenesis and therapy because it acts as both an environmental barrier and as the major interface with the host immune system. Human fungal pathogens use architectural strategies to mask epitopes from the host and prevent immune surveillance, and recent work elucidates how biotic and abiotic stresses present during infection can either block or enhance masking. The signaling components implicated in regulating fungal immune recognition can teach us how cell wall dynamics are controlled, and represent potential targets for interventions designed to boost or dampen immunity. Copyright © 2018 Elsevier Ltd. All rights reserved.

Immunotherapeutic strategies targeting Natural killer T cell responses in cancer

PubMed Central

Shissler, Susannah C.; Bollino, Dominique R.; Tiper, Irina V.; Bates, Joshua; Derakhshandeh, Roshanak; Webb, Tonya J.

2017-01-01

Natural killer T (NKT) cells are a unique subset of lymphocytes that bridge the innate and adaptive immune system. NKT cells possess a classic αβ T-cell receptor (TCR) that is able to recognize self and foreign glycolipid antigens presented by the nonclassical class I major histocompatibility complex (MHC) molecule, CD1d. Type I NKT cells (referred to as invariant NKT cells) express a semi-invariant Vα14Jα18 TCR in mice and Vα24Jα18 TCR in humans. Type II NKT cells are CD1d-restricted T cells that express a more diverse set of TCR α chains. The two types of NKT cells often exert opposing effects especially in tumor immunity, where Type II cells generally suppress tumor immunity while Type I NKT cells can enhance antitumor immune responses. In this review, we focus on the role of NKT cells in cancer. We discuss their effector and suppressive functions, as well as describe preclinical and clinical studies utilizing therapeutic strategies focused on harnessing their potent anti-tumor effector functions, and conclude with a discussion on potential next steps for the utilization of NKT cell targeted therapies for the treatment of cancer. PMID:27393665

Surface receptor Toso controls B cell-mediated regulation of T cell immunity.

PubMed

Yu, Jinbo; Duong, Vu Huy Hoang; Westphal, Katrin; Westphal, Andreas; Suwandi, Abdulhadi; Grassl, Guntram A; Brand, Korbinian; Chan, Andrew C; Föger, Niko; Lee, Kyeong-Hee

2018-05-01

The immune system is tightly controlled by regulatory processes that allow for the elimination of invading pathogens, while limiting immunopathological damage to the host. In the present study, we found that conditional deletion of the cell surface receptor Toso on B cells unexpectedly resulted in impaired proinflammatory T cell responses, which led to impaired immune protection in an acute viral infection model and was associated with reduced immunopathological tissue damage in a chronic inflammatory context. Toso exhibited its B cell-inherent immunoregulatory function by negatively controlling the pool of IL-10-competent B1 and B2 B cells, which were characterized by a high degree of self-reactivity and were shown to mediate immunosuppressive activity on inflammatory T cell responses in vivo. Our results indicate that Toso is involved in the differentiation/maintenance of regulatory B cells by fine-tuning B cell receptor activation thresholds. Furthermore, we showed that during influenza A-induced pulmonary inflammation, the application of Toso-specific antibodies selectively induced IL-10-competent B cells at the site of inflammation and resulted in decreased proinflammatory cytokine production by lung T cells. These findings suggest that Toso may serve as a novel therapeutic target to dampen pathogenic T cell responses via the modulation of IL-10-competent regulatory B cells.

Membrane nanotubes facilitate long-distance interactions between natural killer cells and target cells

PubMed Central

Chauveau, Anne; Aucher, Anne; Eissmann, Philipp; Vivier, Eric; Davis, Daniel M.

2010-01-01

Membrane nanotubes are membranous tethers that physically link cell bodies over long distances. Here, we present evidence that nanotubes allow human natural killer (NK) cells to interact functionally with target cells over long distances. Nanotubes were formed when NK cells contacted target cells and moved apart. The frequency of nanotube formation was dependent on the number of receptor/ligand interactions and increased on NK cell activation. Most importantly, NK cell nanotubes contained a submicron scale junction where proteins accumulated, including DAP10, the signaling adaptor that associates with the activating receptor NKG2D, and MHC class I chain-related protein A (MICA), a cognate ligand for NKG2D, as occurs at close intercellular synapses between NK cells and target cells. Quantitative live-cell fluorescence imaging suggested that MICA accumulated at small nanotube synapses in sufficient numbers to trigger cell activation. In addition, tyrosine-phosphorylated proteins and Vav-1 accumulated at such junctions. Functionally, nanotubes could aid the lysis of distant target cells either directly or by moving target cells along the nanotube path into close contact for lysis via a conventional immune synapse. Target cells moving along the nanotube path were commonly polarized such that their uropods faced the direction of movement. This is the opposite polarization than for normal cell migration, implying that nanotubes can specifically drive target cell movement. Finally, target cells that remained connected to an NK cell by a nanotube were frequently lysed, whereas removing the nanotube using a micromanipulator reduced lysis of these target cells. PMID:20212116

The essential role of G protein-coupled receptor (GPCR) signaling in regulating T cell immunity.

PubMed

Wang, Dashan

2018-06-01

The aim of this paper is to clarify the critical role of GPCR signaling in T cell immunity. The G protein-coupled receptors (GPCRs) are the most common targets in current pharmaceutical industry, and represent the largest and most versatile family of cell surface communicating molecules. GPCRs can be activated by a diverse array of ligands including neurotransmitters, chemokines as well as sensory stimuli. Therefore, GPCRs are involved in many key cellular and physiological processes, such as sense of light, taste and smell, neurotransmission, metabolism, endocrine and exocrine secretion. In recent years, GPCRs have been found to play an important role in immune system. T cell is an important type of immune cell, which plays a central role in cell-mediated immunity. A variety of GPCRs and their signaling mediators (RGS proteins, GRKs and β-arrestin) have been found to express in T cells and involved T cell-mediated immunity. We will summarize the role of GPCR signaling and their regulatory molecules in T cell activation, homeostasis and function in this article. GPCR signaling plays an important role in T cell activation, homeostasis and function. GPCR signaling is critical in regulating T cell immunity.

PSMA-targeted polyinosine/polycytosine vector induces prostate tumor regression and invokes an antitumor immune response in mice.

PubMed

Langut, Yael; Talhami, Alaa; Mamidi, Samarasimhareddy; Shir, Alexei; Zigler, Maya; Joubran, Salim; Sagalov, Anna; Flashner-Abramson, Efrat; Edinger, Nufar; Klein, Shoshana; Levitzki, Alexander

2017-12-26

There is an urgent need for an effective treatment for metastatic prostate cancer (PC). Prostate tumors invariably overexpress prostate surface membrane antigen (PSMA). We designed a nonviral vector, PEI-PEG-DUPA (PPD), comprising polyethylenimine-polyethyleneglycol (PEI-PEG) tethered to the PSMA ligand, 2-[3-(1, 3-dicarboxy propyl)ureido] pentanedioic acid (DUPA), to treat PC. The purpose of PEI is to bind polyinosinic/polycytosinic acid (polyIC) and allow endosomal release, while DUPA targets PC cells. PolyIC activates multiple pathways that lead to tumor cell death and to the activation of bystander effects that harness the immune system against the tumor, attacking nontargeted neighboring tumor cells and reducing the probability of acquired resistance and disease recurrence. Targeting polyIC directly to tumor cells avoids the toxicity associated with systemic delivery. PPD selectively delivered polyIC into PSMA-overexpressing PC cells, inducing apoptosis, cytokine secretion, and the recruitment of human peripheral blood mononuclear cells (PBMCs). PSMA-overexpressing tumors in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with partially reconstituted immune systems were significantly shrunken following PPD/polyIC treatment, in all cases. Half of the tumors showed complete regression. PPD/polyIC invokes antitumor immunity, but unlike many immunotherapies does not need to be personalized for each patient. The potent antitumor effects of PPD/polyIC should spur its development for clinical use.

PSMA-targeted polyinosine/polycytosine vector induces prostate tumor regression and invokes an antitumor immune response in mice

PubMed Central

Langut, Yael; Talhami, Alaa; Mamidi, Samarasimhareddy; Shir, Alexei; Zigler, Maya; Joubran, Salim; Sagalov, Anna; Flashner-Abramson, Efrat; Edinger, Nufar; Klein, Shoshana; Levitzki, Alexander

2017-01-01

There is an urgent need for an effective treatment for metastatic prostate cancer (PC). Prostate tumors invariably overexpress prostate surface membrane antigen (PSMA). We designed a nonviral vector, PEI-PEG-DUPA (PPD), comprising polyethylenimine–polyethyleneglycol (PEI–PEG) tethered to the PSMA ligand, 2-[3-(1, 3-dicarboxy propyl)ureido] pentanedioic acid (DUPA), to treat PC. The purpose of PEI is to bind polyinosinic/polycytosinic acid (polyIC) and allow endosomal release, while DUPA targets PC cells. PolyIC activates multiple pathways that lead to tumor cell death and to the activation of bystander effects that harness the immune system against the tumor, attacking nontargeted neighboring tumor cells and reducing the probability of acquired resistance and disease recurrence. Targeting polyIC directly to tumor cells avoids the toxicity associated with systemic delivery. PPD selectively delivered polyIC into PSMA-overexpressing PC cells, inducing apoptosis, cytokine secretion, and the recruitment of human peripheral blood mononuclear cells (PBMCs). PSMA-overexpressing tumors in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with partially reconstituted immune systems were significantly shrunken following PPD/polyIC treatment, in all cases. Half of the tumors showed complete regression. PPD/polyIC invokes antitumor immunity, but unlike many immunotherapies does not need to be personalized for each patient. The potent antitumor effects of PPD/polyIC should spur its development for clinical use. PMID:29229829

Cystatin F as a regulator of immune cell cytotoxicity.

PubMed

Kos, Janko; Nanut, Milica Perišić; Prunk, Mateja; Sabotič, Jerica; Dautović, Esmeralda; Jewett, Anahid

2018-05-10

Cysteine cathepsins are lysosomal peptidases involved in the regulation of innate and adaptive immune responses. Among the diverse processes, regulation of granule-dependent cytotoxicity of cytotoxic T-lymphocytes (CTLs) and natural killer (NK) cells during cancer progression has recently gained significant attention. The function of cysteine cathepsins is regulated by endogenous cysteine protease inhibitors-cystatins. Whereas other cystatins are generally cytosolic or extracellular proteins, cystatin F is present in endosomes and lysosomes and is thus able to regulate the activity of its target directly. It is delivered to endosomal/lysosomal vesicles as an inactive, disulphide-linked dimer. Proteolytic cleavage of its N-terminal part leads to the monomer, the only form that is a potent inhibitor of cathepsins C, H and L, involved in the activation of granzymes and perforin. In NK cells and CTLs the levels of active cathepsin C and of granzyme B are dependent on the concentration of monomeric, active cystatin F. In tumour microenvironment, inactive dimeric cystatin F can be secreted from tumour cells or immune cells and further taken up by the cytotoxic cells. Subsequent monomerization and inhibition of cysteine cathepsins within the endosomal/lysosomal vesicles impairs granzyme and perforin activation, and provokes cell anergy. Further, the glycosylation pattern has been shown to be important in controlling secretion of cystatin F from target cells, as well as internalization by cytotoxic cells and trafficking to endosomal/lysosomal vesicles. Cystatin F is therefore an important mediator used by bystander cells to reduce NK and T-cell cytotoxicity.

Crosstalk between bone niche and immune system: osteoimmunology signaling as a potential target for cancer treatment.

PubMed

Criscitiello, Carmen; Viale, Giulia; Gelao, Lucia; Esposito, Angela; De Laurentiis, Michele; De Placido, Sabino; Santangelo, Michele; Goldhirsch, Aron; Curigliano, Giuseppe

2015-02-01

There is a well recognized link between the bone and the immune system and in recent years there has been a major effort to elucidate the multiple functions of the molecules expressed in both bone and immune cells. Several molecules that were initially identified and studied in the immune system have been shown to have essential functions also in the bone. An interdisciplinary field embracing immune and bone biology has been brought together and called "osteoimmunology". The co-regulation of the skeletal and immune systems strikingly exemplifies the extreme complexity of such an interaction. Their interdependency must be considered in designing therapeutic approaches for either of the two systems. In other words, it is necessary to think of the osteoimmune system as a complex physiological unit. Denosumab was originally introduced to specifically target bone resorption, but it is now under evaluation for its effect on the long term immune response. Similarly, our current and still growing knowledge of the intimate link between the immune system and bone will be beneficial for the safety of drugs targeting either of these integrated systems. Given the large number of molecules exerting functions on both the skeletal and immune systems, osteoimmunological understanding is becoming increasingly important. Both bone and immune systems are frequently disrupted in cancer; and they may be crucial in regulating tumor growth and progression. Some therapies - such as bisphosphonates and receptor activator of NF-κB ligand (RANKL) targeted drugs - that aim at reducing pathologic osteolysis in cancer may interact with the immune system, thus providing potential favorable effects on survival. Copyright © 2014 Elsevier Ltd. All rights reserved.

Targeting the Genital Tract Mucosa with a Lipopeptide/Recombinant Adenovirus Prime/Boost Vaccine Induces Potent and Long-Lasting CD8+ T Cell Immunity Against Herpes: Importance of Myeloid Differentiation Factor 881

PubMed Central

Zhang, Xiuli; Dervillez, Xavier; Chentoufi, Aziz Alami; Badakhshan, Tina; Bettahi, Ilham; BenMohamed, Lbachir

2012-01-01

Targeting the mucosal immune system of the genital tract (GT) with subunit vaccines failed to induce potent and durable local CD8+ T cell immunity, crucial for protection against many sexually transmitted viral (STV) pathogens, including herpes simplex virus type 2 (HSV-2) that causes genital herpes. In this study, we aimed to investigate the potential of a novel lipopeptide/adenovirus type 5 (Lipo/rAdv5) prime/boost mucosal vaccine for induction of CD8+ T cell immunity to protect the female genital tract from herpes. The lipopeptide and the rAdv5 vaccine express the immunodominant HSV-2 CD8+ T cell epitope (gB498-505) and both were delivered intravaginally (IVAG) in the progesterone-induced B6 mouse model of genital herpes. Compared to its homologous lipopeptide/lipopeptide (Lipo/Lipo); the Lipo/rAdv5 prime/boost immunized mice: (i) developed potent and sustained HSV-specific CD8+ T cells, detected in both the GT draining nodes (GT-DLN) and in the vaginal mucosa (VM); (ii) had significantly lower virus titers; (iii) had decreased overt signs of genital herpes disease; and (iv) did not succumb to lethal infection (p < 0.005), following intravaginal HSV-2 challenge. Polyfunctional CD8+ T cells, producing IFN-γ, TNF-α and IL-2 and exhibiting cytotoxic activity, were associated with protection (p < 0.005). The protective CD8+ T cell response was significantly compromised in the absence of the adaptor myeloid differentiation factor 88 (MyD88) (p = 0.0001). Taken together, these findings indicate that targeting the VM with a Lipo/rAdv5 prime/boost vaccine elicits a potent, MyD88-dependent, and long-lasting mucosal CD8+ T cell protective immunity against sexually transmitted herpes infection and disease. PMID:23018456

CNS infiltration of peripheral immune cells: D-Day for neurodegenerative disease?

PubMed

Rezai-Zadeh, Kavon; Gate, David; Town, Terrence

2009-12-01

While the central nervous system (CNS) was once thought to be excluded from surveillance by immune cells, a concept known as "immune privilege," it is now clear that immune responses do occur in the CNS-giving rise to the field of neuroimmunology. These CNS immune responses can be driven by endogenous (glial) and/or exogenous (peripheral leukocyte) sources and can serve either productive or pathological roles. Recent evidence from mouse models supports the notion that infiltration of peripheral monocytes/macrophages limits progression of Alzheimer's disease pathology and militates against West Nile virus encephalitis. In addition, infiltrating T lymphocytes may help spare neuronal loss in models of amyotrophic lateral sclerosis. On the other hand, CNS leukocyte penetration drives experimental autoimmune encephalomyelitis (a mouse model for the human demyelinating disease multiple sclerosis) and may also be pathological in both Parkinson's disease and human immunodeficiency virus encephalitis. A critical understanding of the cellular and molecular mechanisms responsible for trafficking of immune cells from the periphery into the diseased CNS will be key to target these cells for therapeutic intervention in neurodegenerative diseases, thereby allowing neuroregenerative processes to ensue.

Potent Cell-Intrinsic Immune Responses in Dendritic Cells Facilitate HIV-1-Specific T Cell Immunity in HIV-1 Elite Controllers.

PubMed

Martin-Gayo, Enrique; Buzon, Maria Jose; Ouyang, Zhengyu; Hickman, Taylor; Cronin, Jacqueline; Pimenova, Dina; Walker, Bruce D; Lichterfeld, Mathias; Yu, Xu G

2015-06-01

The majority of HIV-1 elite controllers (EC) restrict HIV-1 replication through highly functional HIV-1-specific T cell responses, but mechanisms supporting the evolution of effective HIV-1-specific T cell immunity in these patients remain undefined. Cytosolic immune recognition of HIV-1 in conventional dendritic cells (cDC) can facilitate priming and expansion of HIV-1-specific T cells; however, HIV-1 seems to be able to avoid intracellular immune recognition in cDCs in most infected individuals. Here, we show that exposure of cDCs from EC to HIV-1 leads to a rapid and sustained production of type I interferons and upregulation of several interferon-stimulated effector genes. Emergence of these cell-intrinsic immune responses was associated with a reduced induction of SAMHD1 and LEDGF/p75, and an accumulation of viral reverse transcripts, but inhibited by pharmacological blockade of viral reverse transcription or siRNA-mediated silencing of the cytosolic DNA sensor cGAS. Importantly, improved cell-intrinsic immune recognition of HIV-1 in cDCs from elite controllers translated into stronger abilities to stimulate and expand HIV-1-specific CD8 T cell responses. These data suggest an important role of cell-intrinsic type I interferon secretion in dendritic cells for the induction of effective HIV-1-specific CD8 T cells, and may be helpful for eliciting functional T cell immunity against HIV-1 for preventative or therapeutic clinical purposes.

Curcumin: A natural modulator of immune cells in systemic lupus erythematosus.

PubMed

Momtazi-Borojeni, Amir Abbas; Haftcheshmeh, Saeed Mohammadian; Esmaeili, Seyed-Alireza; Johnston, Thomas P; Abdollahi, Elham; Sahebkar, Amirhossein

2018-02-01

Curcumin is a polyphenol natural product isolated from turmeric, interacting with different cellular and molecular targets and, consequently, showing a wide range of pharmacological effects. Recent preclinical and clinical trials have revealed immunomodulatory properties of curcumin that arise from its effects on immune cells and mediators involved in the immune response, such as various T-lymphocyte subsets and dendritic cells, as well as different inflammatory cytokines. Systemic lupus erythematosus (SLE) is an inflammatory, chronic autoimmune-mediated disease characterized by the presence of autoantibodies, deposition of immune complexes in various organs, recruitment of autoreactive and inflammatory T cells, and excessive levels of plasma proinflammatory cytokines. The function and numbers of dendritic cells and T cell subsets, such as T helper 1 (Th1), Th17, and regulatory T cells have been found to be significantly altered in SLE. In the present report, we reviewed the results of in vitro, experimental (pre-clinical), and clinical studies pertaining to the modulatory effects that curcumin produces on the function and numbers of dendritic cells and T cell subsets, as well as relevant cytokines that participate in SLE. Copyright © 2017 Elsevier B.V. All rights reserved.

Dead cell phagocytosis and innate immune checkpoint

PubMed Central

Yoon, Kyoung Wan

2017-01-01

The human body loses several billions of cells daily. When cells die in vivo, the corpse of each dead cell is immediately cleared. Specifically, dead cells are efficiently recognized and cleared by multiple types of neighboring phagocytes. Early research on cell death focused more on molecular mechanisms of cell death regulation while the cellular corpses were merely considered cellular debris. However, it has come to light that various biological stimuli following cell death are important for immune regulation. Clearance of normal dead cells occurs silently in immune tolerance. Exogenous or mutated antigens of malignant or infected cells can initiate adaptive immunity, thereby inducing immunogenicity by adjuvant signals. Several pathogens and cancer cells have strategies to limit the adjuvant signals and escape immune surveillance. In this review, we present an overview of the mechanisms of dead cell clearance and its immune regulations. PMID:28768566

Prior Dengue Virus Exposure Shapes T Cell Immunity to Zika Virus in Humans

PubMed Central

Grifoni, Alba; Pham, John; Sidney, John; O'Rourke, Patrick H.; Paul, Sinu; Peters, Bjoern; Martini, Sheridan R.; de Silva, Aruna D.; Ricciardi, Michael J.; Silveira, Cassia G. T.; Maestri, Alvino; Costa, Priscilla R.; de-Oliveira-Pinto, Luzia Maria; de Azeredo, Elzinandes Leal; Damasco, Paulo Vieira; Phillips, Elizabeth; Mallal, Simon; de Silva, Aravinda M.; Collins, Matthew; Durbin, Anna; Diehl, Sean A.; Cerpas, Cristhiam; Balmaseda, Angel; Kuan, Guillermina; Coloma, Josefina; Harris, Eva; Crowe, James E.; Stone, Mars; Busch, Michael; Vivanco-Cid, Hector; Cox, Josephine; Graham, Barney S.; Ledgerwood, Julie E.; Turtle, Lance; Solomon, Tom; Kallas, Esper G.; Watkins, David I.; Weiskopf, Daniela

2017-01-01

ABSTRACT While progress has been made in characterizing humoral immunity to Zika virus (ZIKV) in humans, little is known regarding the corresponding T cell responses to ZIKV. Here, we investigate the kinetics and viral epitopes targeted by T cells responding to ZIKV and address the critical question of whether preexisting dengue virus (DENV) T cell immunity modulates these responses. We find that memory T cell responses elicited by prior infection with DENV or vaccination with tetravalent dengue attenuated vaccines (TDLAV) recognize ZIKV-derived peptides. This cross-reactivity is explained by the sequence similarity of the two viruses, as the ZIKV peptides recognized by DENV-elicited memory T cells are identical or highly conserved in DENV and ZIKV. DENV exposure prior to ZIKV infection also influences the timing and magnitude of the T cell response. ZIKV-reactive T cells in the acute phase of infection are detected earlier and in greater magnitude in DENV-immune patients. Conversely, the frequency of ZIKV-reactive T cells continues to rise in the convalescent phase in DENV-naive donors but declines in DENV-preexposed donors, compatible with more efficient control of ZIKV replication and/or clearance of ZIKV antigen. The quality of responses is also influenced by previous DENV exposure, and ZIKV-specific CD8 T cells from DENV-preexposed donors selectively upregulated granzyme B and PD1, unlike DENV-naive donors. Finally, we discovered that ZIKV structural proteins (E, prM, and C) are major targets of both the CD4 and CD8 T cell responses, whereas DENV T cell epitopes are found primarily in nonstructural proteins. IMPORTANCE The issue of potential ZIKV and DENV cross-reactivity and how preexisting DENV T cell immunity modulates Zika T cell responses is of great relevance, as the two viruses often cocirculate and Zika virus has been spreading in geographical regions where DENV is endemic or hyperendemic. Our data show that memory T cell responses elicited by prior

Chimeric antigen receptor T cells form nonclassical and potent immune synapses driving rapid cytotoxicity.

PubMed

Davenport, A J; Cross, R S; Watson, K A; Liao, Y; Shi, W; Prince, H M; Beavis, P A; Trapani, J A; Kershaw, M H; Ritchie, D S; Darcy, P K; Neeson, P J; Jenkins, M R

2018-02-27

Chimeric antigen receptor T (CAR-T) cells are effective serial killers with a faster off-rate from dying tumor cells than CAR-T cells binding target cells through their T cell receptor (TCR). Here we explored the functional consequences of CAR-mediated signaling using a dual-specific CAR-T cell, where the same cell was triggered via TCR (tcrCTL) or CAR (carCTL). The carCTL immune synapse lacked distinct LFA-1 adhesion rings and was less reliant on LFA to form stable conjugates with target cells. carCTL receptors associated with the synapse were found to be disrupted and formed a convoluted multifocal pattern of Lck microclusters. Both proximal and distal receptor signaling pathways were induced more rapidly and subsequently decreased more rapidly in carCTL than in tcrCTL. The functional consequence of this rapid signaling in carCTL cells included faster lytic granule recruitment to the immune synapse, correlating with faster detachment of the CTL from the target cell. This study provides a mechanism for how CAR-T cells can debulk large tumor burden quickly and may contribute to further refinement of CAR design for enhancing the quality of signaling and programming of the T cell. Copyright © 2018 the Author(s). Published by PNAS.

Chimeric antigen receptor T cells form nonclassical and potent immune synapses driving rapid cytotoxicity

PubMed Central

Davenport, A. J.; Cross, R. S.; Watson, K. A.; Liao, Y.; Shi, W.; Prince, H. M.; Beavis, P. A.; Trapani, J. A.; Kershaw, M. H.; Ritchie, D. S.; Darcy, P. K.; Jenkins, M. R.

2018-01-01

Chimeric antigen receptor T (CAR-T) cells are effective serial killers with a faster off-rate from dying tumor cells than CAR-T cells binding target cells through their T cell receptor (TCR). Here we explored the functional consequences of CAR-mediated signaling using a dual-specific CAR-T cell, where the same cell was triggered via TCR (tcrCTL) or CAR (carCTL). The carCTL immune synapse lacked distinct LFA-1 adhesion rings and was less reliant on LFA to form stable conjugates with target cells. carCTL receptors associated with the synapse were found to be disrupted and formed a convoluted multifocal pattern of Lck microclusters. Both proximal and distal receptor signaling pathways were induced more rapidly and subsequently decreased more rapidly in carCTL than in tcrCTL. The functional consequence of this rapid signaling in carCTL cells included faster lytic granule recruitment to the immune synapse, correlating with faster detachment of the CTL from the target cell. This study provides a mechanism for how CAR-T cells can debulk large tumor burden quickly and may contribute to further refinement of CAR design for enhancing the quality of signaling and programming of the T cell. PMID:29440406

Circulating TFH cells, serological memory, and tissue compartmentalization shape human influenza-specific B cell immunity.

PubMed

Koutsakos, Marios; Wheatley, Adam K; Loh, Liyen; Clemens, E Bridie; Sant, Sneha; Nüssing, Simone; Fox, Annette; Chung, Amy W; Laurie, Karen L; Hurt, Aeron C; Rockman, Steve; Lappas, Martha; Loudovaris, Thomas; Mannering, Stuart I; Westall, Glen P; Elliot, Michael; Tangye, Stuart G; Wakim, Linda M; Kent, Stephen J; Nguyen, Thi H O; Kedzierska, Katherine

2018-02-14

Immunization with the inactivated influenza vaccine (IIV) remains the most effective strategy to combat seasonal influenza infections. IIV activates B cells and T follicular helper (T FH ) cells and thus engenders antibody-secreting cells and serum antibody titers. However, the cellular events preceding generation of protective immunity in humans are inadequately understood. We undertook an in-depth analysis of B cell and T cell immune responses to IIV in 35 healthy adults. Using recombinant hemagglutinin (rHA) probes to dissect the quantity, phenotype, and isotype of influenza-specific B cells against A/California09-H1N1, A/Switzerland-H3N2, and B/Phuket, we showed that vaccination induced a three-pronged B cell response comprising a transient CXCR5 - CXCR3 + antibody-secreting B cell population, CD21 hi CD27 + memory B cells, and CD21 lo CD27 + B cells. Activation of circulating T FH cells correlated with the development of both CD21 lo and CD21 hi memory B cells. However, preexisting antibodies could limit increases in serum antibody titers. IIV had no marked effect on CD8 + , mucosal-associated invariant T, γδ T, and natural killer cell activation. In addition, vaccine-induced B cells were not maintained in peripheral blood at 1 year after vaccination. We provide a dissection of rHA-specific B cells across seven human tissue compartments, showing that influenza-specific memory (CD21 hi CD27 + ) B cells primarily reside within secondary lymphoid tissues and the lungs. Our study suggests that a rational design of universal vaccines needs to consider circulating T FH cells, preexisting serological memory, and tissue compartmentalization for effective B cell immunity, as well as to improve targeting cellular T cell immunity. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Monitoring dynamic interactions of tumor cells with tissue and immune cells in a lab-on-a-chip.

PubMed

Charwat, Verena; Rothbauer, Mario; Tedde, Sandro F; Hayden, Oliver; Bosch, Jacobus J; Muellner, Paul; Hainberger, Rainer; Ertl, Peter

2013-12-03

A complementary cell analysis method has been developed to assess the dynamic interactions of tumor cells with resident tissue and immune cells using optical light scattering and impedance sensing to shed light on tumor cell behavior. The combination of electroanalytical and optical biosensing technologies integrated in a lab-on-a-chip allows for continuous, label-free, and noninvasive probing of dynamic cell-to-cell interactions between adherent and nonadherent cocultures, thus providing real-time insights into tumor cell responses under physiologically relevant conditions. While the study of adherent cocultures is important for the understanding and suppression of metastatic invasion, the analysis of tumor cell interactions with nonadherent immune cells plays a vital role in cancer immunotherapy research. For the first time, the direct cell-to-cell interactions of tumor cells with bead-activated primary T cells were continuously assessed using an effector cell to target a cell ratio of 10:1.

Dead cell phagocytosis and innate immune checkpoint.

PubMed

Yoon, Kyoung Wan

2017-10-01

The human body loses several billions of cells daily. When cells die in vivo, the corpse of each dead cell is immediately cleared. Specifically, dead cells are efficiently recognized and cleared by multiple types of neighboring phagocytes. Early research on cell death focused more on molecular mechanisms of cell death regulation while the cellular corpses were merely considered cellular debris. However, it has come to light that various biological stimuli following cell death are important for immune regulation. Clearance of normal dead cells occurs silently in immune tolerance. Exogenous or mutated antigens of malignant or infected cells can initiate adaptive immunity, thereby inducing immunogenicity by adjuvant signals. Several pathogens and cancer cells have strategies to limit the adjuvant signals and escape immune surveillance. In this review, we present an overview of the mechanisms of dead cell clearance and its immune regulations. [BMB Reports 2017; 50(10): 496-503].

Dendritic Cell Immune Responses in HIV-1 Controllers.

PubMed

Martin-Gayo, Enrique; Yu, Xu G

2017-02-01

Robust HIV-1-specific CD8 T cell responses are currently regarded as the main correlate of immune defense in rare individuals who achieve natural, drug-free control of HIV-1; however, the mechanisms that support evolution of such powerful immune responses are not well understood. Dendritic cells (DCs) are specialized innate immune cells critical for immune recognition, immune regulation, and immune induction, but their possible contribution to HIV-1 immune defense in controllers remains ill-defined. Recent studies suggest that myeloid DCs from controllers have improved abilities to recognize HIV-1 through cytoplasmic immune sensors, resulting in more potent, cell-intrinsic type I interferon secretion in response to viral infection. This innate immune response may facilitate DC-mediated induction of highly potent antiviral HIV-1-specific T cells. Moreover, protective HLA class I isotypes restricting HIV-1-specific CD8 T cells may influence DC function through specific interactions with innate myelomonocytic MHC class I receptors from the leukocyte immunoglobulin-like receptor family. Bi-directional interactions between dendritic cells and HIV-1-specific T cells may contribute to natural HIV-1 immune control, highlighting the importance of a fine-tuned interplay between innate and adaptive immune activities for effective antiviral immune defense.

Dual targeting of glioblastoma with chimeric antigen receptor-engineered natural killer cells overcomes heterogeneity of target antigen expression and enhances antitumor activity and survival.

PubMed

Genßler, Sabrina; Burger, Michael C; Zhang, Congcong; Oelsner, Sarah; Mildenberger, Iris; Wagner, Marlies; Steinbach, Joachim P; Wels, Winfried S

2016-04-01

Epidermal growth factor receptor (EGFR) and its mutant form EGFRvIII are overexpressed in a large proportion of glioblastomas (GBM). Immunotherapy with an EGFRvIII-specific vaccine has shown efficacy against GBM in clinical studies. However, immune escape by antigen-loss variants and lack of control of EGFR wild-type positive clones limit the usefulness of this approach. Chimeric antigen receptor (CAR)-engineered natural killer (NK) cells may represent an alternative immunotherapeutic strategy. For targeting to GBM, we generated variants of the clinically applicable human NK cell line NK-92 that express CARs carrying a composite CD28-CD3ζ domain for signaling, and scFv antibody fragments for cell binding either recognizing EGFR, EGFRvIII, or an epitope common to both antigens. In vitro analysis revealed high and specific cytotoxicity of EGFR-targeted NK-92 against established and primary human GBM cells, which was dependent on EGFR expression and CAR signaling. EGFRvIII-targeted NK-92 only lysed EGFRvIII-positive GBM cells, while dual-specific NK cells expressing a cetuximab-based CAR were active against both types of tumor cells. In immunodeficient mice carrying intracranial GBM xenografts either expressing EGFR, EGFRvIII or both receptors, local treatment with dual-specific NK cells was superior to treatment with the corresponding monospecific CAR NK cells. This resulted in a marked extension of survival without inducing rapid immune escape as observed upon therapy with monospecific effectors. Our results demonstrate that dual targeting of CAR NK cells reduces the risk of immune escape and suggest that EGFR/EGFRvIII-targeted dual-specific CAR NK cells may have potential for adoptive immunotherapy of glioblastoma.

Immune checkpoint inhibitors for nonsmall cell lung cancer treatment.

PubMed

Chen, Yuh-Min

2017-01-01

Immune checkpoint inhibition with blocking antibodies that target cytotoxic T-lymphocyte antigen-4 (CTLA-4) and the programmed cell death protein 1 (PD-1) pathway [PD-1/programmed death-ligand 1 (PD-L1)] have demonstrated promise in a variety of malignancies. While ipilimumab has been approved as a CTLA-4 blocking antibody by the US Food and Drug Administration for the treatment of advanced melanoma, it is still not approved for lung cancer treatment. In contrast, nivolumab and pembrolizumab, both PD-1 blocking antibodies, have been approved for second-line treatment of nonsmall cell lung cancer in 2015 because of their high potency and long-lasting effects in some patient subgroups. Other PD-1 and PD-L1 monoclonal antibodies are also in active development phase. Treatment with such immune checkpoint inhibitors is associated with a unique pattern of immune-related adverse events or side effects. Combination approaches involving CTLA-4 and PD-1/PD-L1 blockade or checkpoint inhibitors with chemotherapy or radiotherapy are being investigated to determine whether they may enhance the efficacy of treatment. Despite many challenges ahead, immunotherapy with checkpoint inhibitors has already become a new and important treatment modality for lung cancer in the last decade following the discovery of targeted therapy. Copyright © 2016. Published by Elsevier Taiwan LLC.

Immunogenic cancer cell death selectively induced by near infrared photoimmunotherapy initiates host tumor immunity.

PubMed

Ogawa, Mikako; Tomita, Yusuke; Nakamura, Yuko; Lee, Min-Jung; Lee, Sunmin; Tomita, Saori; Nagaya, Tadanobu; Sato, Kazuhide; Yamauchi, Toyohiko; Iwai, Hidenao; Kumar, Abhishek; Haystead, Timothy; Shroff, Hari; Choyke, Peter L; Trepel, Jane B; Kobayashi, Hisataka

2017-02-07

Immunogenic cell death (ICD) is a form of cell death that activates an adaptive immune response against dead-cell-associated antigens. Cancer cells killed via ICD can elicit antitumor immunity. ICD is efficiently induced by near-infrared photo-immunotherapy (NIR-PIT) that selectively kills target-cells on which antibody-photoabsorber conjugates bind and are activated by NIR light exposure. Advanced live cell microscopies showed that NIR-PIT caused rapid and irreversible damage to the cell membrane function leading to swelling and bursting, releasing intracellular components due to the influx of water into the cell. The process also induces relocation of ICD bio markers including calreticulin, Hsp70 and Hsp90 to the cell surface and the rapid release of immunogenic signals including ATP and HMGB1 followed by maturation of immature dendritic cells. Thus, NIR-PIT is a therapy that kills tumor cells by ICD, eliciting a host immune response against tumor.

Targeting innate immunity for neurodegenerative disorders of the central nervous system.

PubMed

Andreasson, Katrin I; Bachstetter, Adam D; Colonna, Marco; Ginhoux, Florent; Holmes, Clive; Lamb, Bruce; Landreth, Gary; Lee, Daniel C; Low, Donovan; Lynch, Marina A; Monsonego, Alon; O'Banion, M Kerry; Pekny, Milos; Puschmann, Till; Russek-Blum, Niva; Sandusky, Leslie A; Selenica, Maj-Linda B; Takata, Kazuyuki; Teeling, Jessica; Town, Terrence; Van Eldik, Linda J

2016-09-01

Neuroinflammation is critically involved in numerous neurodegenerative diseases, and key signaling steps of innate immune activation hence represent promising therapeutic targets. This mini review series originated from the 4th Venusberg Meeting on Neuroinflammation held in Bonn, Germany, 7-9th May 2015, presenting updates on innate immunity in acute brain injury and chronic neurodegenerative disorders, such as traumatic brain injury and Alzheimer disease, on the role of astrocytes and microglia, as well as technical developments that may help elucidate neuroinflammatory mechanisms and establish clinical relevance. In this meeting report, a brief overview of physiological and pathological microglia morphology is followed by a synopsis on PGE2 receptors, insights into the role of arginine metabolism and further relevant aspects of neuroinflammation in various clinical settings, and concluded by a presentation of technical challenges and solutions when working with microglia and astrocyte cultures. Microglial ontogeny and induced pluripotent stem cell-derived microglia, advances of TREM2 signaling, and the cytokine paradox in Alzheimer's disease are further contributions to this article. Neuroinflammation is critically involved in numerous neurodegenerative diseases, and key signaling steps of innate immune activation hence represent promising therapeutic targets. This mini review series originated from the 4th Venusberg Meeting on Neuroinflammation held in Bonn, Germany, 7-9th May 2015, presenting updates on innate immunity in acute brain injury and chronic neurodegenerative disorders, such as traumatic brain injury and Alzheimer's disease, on the role of astrocytes and microglia, as well as technical developments that may help elucidate neuroinflammatory mechanisms and establish clinical relevance. In this meeting report, a brief overview on physiological and pathological microglia morphology is followed by a synopsis on PGE2 receptors, insights into the role of

Immune cells in term and preterm labor

PubMed Central

Gomez-Lopez, Nardhy; StLouis, Derek; Lehr, Marcus A; Sanchez-Rodriguez, Elly N; Arenas-Hernandez, Marcia

2014-01-01

Labor resembles an inflammatory response that includes secretion of cytokines/chemokines by resident and infiltrating immune cells into reproductive tissues and the maternal/fetal interface. Untimely activation of these inflammatory pathways leads to preterm labor, which can result in preterm birth. Preterm birth is a major determinant of neonatal mortality and morbidity; therefore, the elucidation of the process of labor at a cellular and molecular level is essential for understanding the pathophysiology of preterm labor. Here, we summarize the role of innate and adaptive immune cells in the physiological or pathological activation of labor. We review published literature regarding the role of innate and adaptive immune cells in the cervix, myometrium, fetal membranes, decidua and the fetus in late pregnancy and labor at term and preterm. Accumulating evidence suggests that innate immune cells (neutrophils, macrophages and mast cells) mediate the process of labor by releasing pro-inflammatory factors such as cytokines, chemokines and matrix metalloproteinases. Adaptive immune cells (T-cell subsets and B cells) participate in the maintenance of fetomaternal tolerance during pregnancy, and an alteration in their function or abundance may lead to labor at term or preterm. Also, immune cells that bridge the innate and adaptive immune systems (natural killer T (NKT) cells and dendritic cells (DCs)) seem to participate in the pathophysiology of preterm labor. In conclusion, a balance between innate and adaptive immune cells is required in order to sustain pregnancy; an alteration of this balance will lead to labor at term or preterm. PMID:24954221

Genomic correlates of response to immune checkpoint therapies in clear cell renal cell carcinoma.

PubMed

Miao, Diana; Margolis, Claire A; Gao, Wenhua; Voss, Martin H; Li, Wei; Martini, Dylan J; Norton, Craig; Bossé, Dominick; Wankowicz, Stephanie M; Cullen, Dana; Horak, Christine; Wind-Rotolo, Megan; Tracy, Adam; Giannakis, Marios; Hodi, Frank Stephen; Drake, Charles G; Ball, Mark W; Allaf, Mohamad E; Snyder, Alexandra; Hellmann, Matthew D; Ho, Thai; Motzer, Robert J; Signoretti, Sabina; Kaelin, William G; Choueiri, Toni K; Van Allen, Eliezer M

2018-02-16

Immune checkpoint inhibitors targeting the programmed cell death 1 receptor (PD-1) improve survival in a subset of patients with clear cell renal cell carcinoma (ccRCC). To identify genomic alterations in ccRCC that correlate with response to anti-PD-1 monotherapy, we performed whole-exome sequencing of metastatic ccRCC from 35 patients. We found that clinical benefit was associated with loss-of-function mutations in the PBRM1 gene ( P = 0.012), which encodes a subunit of the PBAF switch-sucrose nonfermentable (SWI/SNF) chromatin remodeling complex. We confirmed this finding in an independent validation cohort of 63 ccRCC patients treated with PD-1 or PD-L1 (PD-1 ligand) blockade therapy alone or in combination with anti-CTLA-4 (cytotoxic T lymphocyte-associated protein 4) therapies ( P = 0.0071). Gene-expression analysis of PBAF-deficient ccRCC cell lines and PBRM1 -deficient tumors revealed altered transcriptional output in JAK-STAT (Janus kinase-signal transducers and activators of transcription), hypoxia, and immune signaling pathways. PBRM1 loss in ccRCC may alter global tumor-cell expression profiles to influence responsiveness to immune checkpoint therapy. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Mechanisms of peripheral immune-cell-mediated analgesia in inflammation: clinical and therapeutic implications.

PubMed

Hua, Susan; Cabot, Peter J

2010-09-01

Peripheral mechanisms of endogenous pain control are significant. In peripheral inflamed tissue, an interaction between immune-cell-derived opioids and opioid receptors localized on sensory nerve terminals results in potent, clinically measurable analgesia. Opioid peptides and the mRNA encoding their precursor proteins are present in immune cells. These cells 'home' preferentially to injured tissue, where they secrete opioids to reduce pain. Investigation of the mechanisms underlying the migration of opioid-containing immune cells to inflamed tissue is an active area of research, with recent data demonstrating the importance of cell adhesion molecules in leukocyte adhesion to both the endothelium in vascular transmigration and to neurons within peripheral inflamed tissue. This review summarizes the physiological mechanisms and clinical significance of this unique endogenous peripheral analgesic pathway and discusses therapeutic implications for the development of novel targeted peripheral analgesics. Copyright 2010 Elsevier Ltd. All rights reserved.

Targeting Fibroblast Activation Protein in Tumor Stroma with Chimeric Antigen Receptor T Cells Can Inhibit Tumor Growth and Augment Host Immunity Without Severe Toxicity

PubMed Central

Wang, Liang-Chuan S; Lo, Albert; Scholler, John; Sun, Jing; Majumdar, Rajrupa S; Kapoor, Veena; Antzis, Michael; Cotner, Cody E.; Johnson, Laura A; Durham, Amy C; Solomides, Charalambos C.; June, Carl H; Puré, Ellen; Albelda, Steven M

2013-01-01

The majority of chimeric antigen receptor (CAR) T cell research has focused on attacking cancer cells. Here we show that targeting the tumor-promoting, non-transformed stromal cells using CAR T cells may offer several advantages. We developed a retroviral CAR construct specific for the mouse fibroblast activation protein (FAP), comprising a single chain Fv FAP (mAb 73.3) with the CD8α hinge and transmembrane regions, and the human CD3ζ and 4-1BB activation domains. The transduced muFAP-CAR mouse T cells secreted IFNγ and killed FAP-expressing 3T3 target cells specifically. Adoptively transferred 73.3-FAP-CAR mouse T cells selectively reduced FAPhi stromal cells and inhibited the growth of multiple types of subcutaneously transplanted tumors in wild-type, but not FAP-null immune-competent syngeneic mice. The antitumor effects could be augmented by multiple injections of the CAR T cells, by using CAR T cells with a deficiency in diacylglycerol kinase, or by combination with a vaccine. A major mechanism of action of the muFAP-CAR T cells was the augmentation of the endogenous CD8+ T cell antitumor responses. Off-tumor toxicity in our models was minimal following muFAP-CAR T cell therapy. In summary, inhibiting tumor growth by targeting tumor stroma with adoptively transferred CAR T cells directed to FAP can be safe and effective suggesting that further clinical development of anti-human FAP-CAR is warranted. PMID:24778279

CD147 stimulates hepatoma cells escaping from immune surveillance of T cells by interaction with Cyclophilin A.

PubMed

Ren, Yi-Xin; Wang, Shu-Jing; Fan, Jian-Hui; Sun, Shi-Jie; Li, Xia; Padhiar, Arshad Ahmed; Zhang, Jia-Ning

2016-05-01

T cells play an important role in tumor immune surveillance. CD147 is a member of immunoglobulin superfamily present on the surface of many tumor cells and mediates malignant cell behaviors. Cyclophilin A (CypA) is an intracellular protein promoting inflammation when released from cells. CypA is a natural ligand for CD147. In this study, CD147 specific short hairpin RNAs (shRNA) were transfected into murine hepatocellular carcinoma Hepa1-6 cells to assess the effects of CD147 on hepatoma cells escaping from immune surveillance of T cells. We found extracellular CypA stimulated cell proliferation through CD147 by activating ERK1/2 signaling pathway. Downregulation of CD147 expression on Hepa1-6 cells significantly suppressed tumor progression in vivo, and decreased cell viability when co-cultured with T cells in vitro. Importantly, knockdown of CD147 on Hepa1-6 cells resulted in significantly increased T cells chemotaxis induced by CypA both in vivo and in vitro. These findings provide novel mechanisms how tumor cells escaping from immune surveillance of T cells. We provide a potential therapy for hepatocellular carcinoma by targeting CD147 or CD147-CypA interactions. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Mast cell, the peculiar member of the immune system: A homeostatic aspect.

PubMed

Csaba, György

2015-09-01

The mast cell is a member of the immune system having a basic role in allergic (anaphylactic) reactions. However, it contains, synthesizes, stores and secretes lots of substances, which initiates other reactions or participates in them. These are in connection with the deterioration of tissue correlation, as malignant tumors, angiogenesis, wound healing, pregnancy and different pathological conditions. In addition - as other members of the immune system - mast cells can synthesize, store and secrete hormones characteristic to the endocrine glands and can transport them to the site of requirement (packed transport), or produce and employ them locally. The effect of mast cells is controversial and frequently dual, stimulatory or inhibitory to the same organ or process. This is likely due to the heterogeneity of the mast cells, in morphology and cell content alike and dependent on the actual condition of the targeted tissue. The cells are transported in an unmatured form by the blood circulation and are exposed to microenvironmental effects, which influence their maturation. Their enrichment around tumors suggested using them as targets for tumor therapy more than fifty years ago (by the author), however, this idea lives its renaissance now. The review discusses the facts and ideas critically.

Orchestration of Angiogenesis by Immune Cells

PubMed Central

Bruno, Antonino; Pagani, Arianna; Pulze, Laura; Albini, Adriana; Dallaglio, Katiuscia; Noonan, Douglas M.; Mortara, Lorenzo

2014-01-01

It is widely accepted that the tumor microenvironment (TUMIC) plays a major role in cancer and is indispensable for tumor progression. The TUMIC involves many “players” going well beyond the malignant-transformed cells, including stromal, immune, and endothelial cells (ECs). The non-malignant cells can acquire tumor-promoting functions during carcinogenesis. In particular, these cells can “orchestrate” the “symphony” of the angiogenic switch, permitting the creation of new blood vessels that allows rapid expansion and progression toward malignancy. Considerable attention within the context of tumor angiogenesis should focus not only on the ECs, representing a fundamental unit, but also on immune cells and on the inflammatory tumor infiltrate. Immune cells infiltrating tumors typically show a tumor-induced polarization associated with attenuation of anti-tumor functions and generation of pro-tumor activities, among these angiogenesis. Here, we propose a scenario suggesting that the angiogenic switch is an immune switch arising from the pro-angiogenic polarization of immune cells. This view links immunity, inflammation, and angiogenesis to tumor progression. Here, we review the data in the literature and seek to identify the “conductors” of this “orchestra.” We also suggest that interrupting the immune → inflammation → angiogenesis → tumor progression process can delay or prevent tumor insurgence and malignant disease. PMID:25072019

Indoleamine 2,3-dioxygenase specific, cytotoxic T cells as immune regulators.

PubMed

Sørensen, Rikke Baek; Hadrup, Sine Reker; Svane, Inge Marie; Hjortsø, Mads Christian; Thor Straten, Per; Andersen, Mads Hald

2011-02-17

Indoleamine 2,3-dioxygenase (IDO) is an immunoregulatory enzyme that is implicated in suppressing T-cell immunity in normal and pathologic settings. Here, we describe that spontaneous cytotoxic T-cell reactivity against IDO exists not only in patients with cancer but also in healthy persons. We show that the presence of such IDO-specific CD8(+) T cells boosted T-cell immunity against viral or tumor-associated antigens by eliminating IDO(+) suppressive cells. This had profound effects on the balance between interleukin-17 (IL-17)-producing CD4(+) T cells and regulatory T cells. Furthermore, this caused an increase in the production of the proinflammatory cytokines IL-6 and tumor necrosis factor-α while decreasing the IL-10 production. Finally, the addition of IDO-inducing agents (ie, the TLR9 ligand cytosine-phosphate-guanosine, soluble cytotoxic T lymphocyte-associated antigen 4, or interferon γ) induced IDO-specific T cells among peripheral blood mononuclear cells from patients with cancer as well as healthy donors. In the clinical setting, IDO may serve as an important and widely applicable target for immunotherapeutic strategies in which IDO plays a significant regulatory role. We describe for the first time effector T cells with a general regulatory function that may play a vital role for the mounting or maintaining of an effective adaptive immune response. We suggest terming such effector T cells "supporter T cells."

Induction of viral interference by IPNV-carrier cells on target cells: A cell co-culture study.

PubMed

Parreño, Ricardo; Torres, Susana; Almagro, Lucía; Belló-Pérez, Melissa; Estepa, Amparo; Perez, Luis

2016-11-01

IPNV is a salmonid birnavirus that possesses the ability to establish asymptomatic persistent infections in a number of valuable fish species. The presence of IPNV may interfere with subsequent infection by other viruses. In the present study we show that an IPNV-carrier cell line (EPC IPNV ) can induce an antiviral state in fresh EPC by co-cultivating both cell types in three different ways: a "droplet" culture system, a plastic chamber setup, and a transmembrane (Transwell ® ) system. All three cell co-culture methods were proven useful to study donor/target cell interaction. Naïve EPC cells grown in contact with EPC IPNV cells develop resistance to VHSV superinfection. The transmembrane system seems best suited to examine gene expression in donor and target cells separately. Our findings point to the conclusion that one or more soluble factors produced by the IPNV carrier culture induce the innate immune response within the target cells. This antiviral response is associated to the up-regulation of interferon (ifn) and mx gene expression in target EPC cells. To our knowledge this is the first article describing co-culture systems to study the interplay between virus-carrier cells and naive cells in fish. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Functionalized Iron Oxide Nanoparticles for Controlling the Movement of Immune Cells

PubMed Central

White, Ethan E; Pai, Alex; Weng, Yiming; Suresh, Anil K.; Van Haute, Desiree; Pailevanian, Torkom; Alizadeh, Darya; Hajimiri, Ali; Badie, Behnam; Berlin, Jacob M.

2015-01-01

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed “cell box” was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain. PMID:25848983

Functionalized iron oxide nanoparticles for controlling the movement of immune cells.

PubMed

White, Ethan E; Pai, Alex; Weng, Yiming; Suresh, Anil K; Van Haute, Desiree; Pailevanian, Torkom; Alizadeh, Darya; Hajimiri, Ali; Badie, Behnam; Berlin, Jacob M

2015-05-07

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed "cell box" was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain.

Prior Dengue virus exposure shapes T cell immunity to Zika virus in humans.

PubMed

Grifoni, Alba; Pham, John; Sidney, John; O'Rourke, Patrick H; Paul, Sinu; Peters, Bjoern; Martini, Sheridan R; de Silva, Aruna D; Ricciardi, Michael J; Magnani, Diogo M; Silveira, Cassia G T; Maestri, Alvino; Costa, Priscilla R; de-Oliveira-Pinto, Luzia Maria; de Azeredo, Elzinandes Leal; Damasco, Paulo Vieira; Phillips, Elizabeth; Mallal, Simon; de Silva, Aravinda M; Collins, Matthew; Durbin, Anna; Diehl, Sean A; Cerpas, Cristhiam; Balmaseda, Angel; Kuan, Guillermina; Coloma, Josefina; Harris, Eva; Crowe, James E; Stone, Mars; Norris, Phillip J; Busch, Michael; Vivanco-Cid, Hector; Cox, Josephine; Graham, Barney S; Ledgerwood, Julie E; Turtle, Lance; Solomon, Tom; Kallas, Esper G; Watkins, David I; Weiskopf, Daniela; Sette, Alessandro

2017-10-04

While progress has been made in characterizing humoral immunity to Zika virus (ZIKV) in humans, little is known regarding the corresponding T cell responses to ZIKV. Here we investigate the kinetics and viral epitopes targeted by T cells responding to ZIKV and address the critical question of whether pre-existing dengue virus (DENV) T cell immunity modulates these responses. We find that memory T cell responses elicited by prior infection with DENV or vaccination with Tetravalent Dengue Attenuated Vaccines (TDLAV) recognize ZIKV-derived peptides. This cross-reactivity is explained by the sequence similarity of the two viruses, as the ZIKV peptides recognized by DENV-elicited memory T cells are identical or highly conserved in DENV and ZIKV. DENV exposure prior to ZIKV infection also influences the timing and magnitude of the T cell response. ZIKV-reactive T cells in the acute phase of infection are detected earlier and in greater magnitude in DENV-immune patients. Conversely, the frequency of ZIKV-reactive T cells continues to rise in the convalescent phase in DENV-naive donors, but declines in DENV pre-exposed donors, compatible with more efficient control of ZIKV replication and/or clearance of ZIKV antigen. The quality of responses is also influenced by previous DENV exposure, and ZIKV-specific CD8 T cells form DENV pre-exposed donors selectively up-regulated granzyme B and PD1, as compared to DENV-naïve donors. Finally, we discovered that ZIKV structural proteins (E, prM and C) are major targets of both the CD4 and CD8 T cell responses, whereas DENV T cell epitopes are found primarily in nonstructural proteins. IMPORTANCE The issue of potential ZIKV and DENV cross-reactivity and how pre-existing DENV T cell immunity modulates ZIKA T cell responses is of great relevance as the two viruses often co-circulate and ZIKA virus has been spreading in geographical regions where DENV is endemic or hyper-endemic. Our data show that memory T cell responses elicited by

TGF-β in inflammatory bowel disease: a key regulator of immune cells, epithelium, and the intestinal microbiota.

PubMed

Ihara, Sozaburo; Hirata, Yoshihiro; Koike, Kazuhiko

2017-07-01

Inflammatory bowel disease (IBD) is defined as chronic intestinal inflammation, and includes ulcerative colitis and Crohn's disease. Multiple factors are involved in the pathogenesis of IBD, and the condition is characterized by aberrant mucosal immune reactions to intestinal microbes in genetically susceptible hosts. Transforming growth factor-β (TGF-β) is an immune-suppressive cytokine produced by many cell types and activated by integrins. Active TGF-β binds to its receptor and regulates mucosal immune reactions through the TGF-β signaling pathway. Dysregulated TGF-β signaling is observed in the intestines of IBD patients. TGF-β signal impairment in specific cell types, such as T-cells and dendritic cells, results in spontaneous colitis in mouse models. In addition, specific intestinal microbes contribute to immune homeostasis by modulating TGF-β production. In this review, we describe the role of TGF-β in intestinal immunity, focusing on immune cells, epithelium, and intestinal microbes. In addition, we present potential therapeutic strategies for IBD that target TGF-β.

Anthrax Lethal Factor as an Immune Target in Humans and Transgenic Mice and the Impact of HLA Polymorphism on CD4+ T Cell Immunity

PubMed Central

Ascough, Stephanie; Ingram, Rebecca J.; Chu, Karen K.; Reynolds, Catherine J.; Musson, Julie A.; Doganay, Mehmet; Metan, Gökhan; Ozkul, Yusuf; Baillie, Les; Sriskandan, Shiranee; Moore, Stephen J.; Gallagher, Theresa B.; Dyson, Hugh; Williamson, E. Diane; Robinson, John H.; Maillere, Bernard; Boyton, Rosemary J.; Altmann, Daniel M.

2014-01-01

Bacillus anthracis produces a binary toxin composed of protective antigen (PA) and one of two subunits, lethal factor (LF) or edema factor (EF). Most studies have concentrated on induction of toxin-specific antibodies as the correlate of protective immunity, in contrast to which understanding of cellular immunity to these toxins and its impact on infection is limited. We characterized CD4+ T cell immunity to LF in a panel of humanized HLA-DR and DQ transgenic mice and in naturally exposed patients. As the variation in antigen presentation governed by HLA polymorphism has a major impact on protective immunity to specific epitopes, we examined relative binding affinities of LF peptides to purified HLA class II molecules, identifying those regions likely to be of broad applicability to human immune studies through their ability to bind multiple alleles. Transgenics differing only in their expression of human HLA class II alleles showed a marked hierarchy of immunity to LF. Immunogenicity in HLA transgenics was primarily restricted to epitopes from domains II and IV of LF and promiscuous, dominant epitopes, common to all HLA types, were identified in domain II. The relevance of this model was further demonstrated by the fact that a number of the immunodominant epitopes identified in mice were recognized by T cells from humans previously infected with cutaneous anthrax and from vaccinated individuals. The ability of the identified epitopes to confer protective immunity was demonstrated by lethal anthrax challenge of HLA transgenic mice immunized with a peptide subunit vaccine comprising the immunodominant epitopes that we identified. PMID:24788397

Functionalized iron oxide nanoparticles for controlling the movement of immune cells

NASA Astrophysics Data System (ADS)

White, Ethan E.; Pai, Alex; Weng, Yiming; Suresh, Anil K.; van Haute, Desiree; Pailevanian, Torkom; Alizadeh, Darya; Hajimiri, Ali; Badie, Behnam; Berlin, Jacob M.

2015-04-01

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed ``cell box'' was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain.Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were

Mast cell activators as novel immune regulators.

PubMed

Johnson-Weaver, Brandi; Choi, Hae Woong; Abraham, Soman N; Staats, Herman F

2018-05-26

Mast cells are an important cell type of the innate immune system that when activated, play a crucial role in generating protective innate host responses after bacterial and viral infection. Additionally, activated mast cells influence lymph node composition to regulate the induction of adaptive immune responses. The recognition that mast cells play a beneficial role in host responses to microbial infection and induction of adaptive immunity has provided the rationale to evaluate mast cell activators for use as antimicrobials or vaccine adjuvants. This review summarizes the role of mast cell activators in antimicrobial responses while also discussing the use of different classes of mast cell activators as potent vaccine adjuvants that enhance the induction of protective immune responses. Copyright © 2018 Elsevier Ltd. All rights reserved.

TLR10 is a B-cell Intrinsic Suppressor of Adaptive Immune Responses

PubMed Central

Hess, Nicholas J.; Jiang, Song; Li, Xinyan; Guan, Yue; Tapping, Richard I.

2016-01-01

Toll-like receptors (TLRs) play a central role in the initiation of adaptive immune responses with several TLR agonists acting as known B-cell mitogens. Despite thousands of publications on TLRs, the function of TLR10 remains unknown. We have found that antibody mediated engagement of TLR10 on primary human B-cells suppresses B-cell proliferation, cytokine production and signal transduction. When challenged with either a T-independent or T-dependent antigen, TLR10 transgenic mice exhibit diminished antibody responses. Adoptive transfer of splenic B-cells into B-cell deficient mice revealed that the suppressive effects on antigen-specific humoral immune responses are entirely B-cell intrinsic. Our results demonstrate that TLR10 has a functional role within the B-cell lineage that is distinct from that of other TLR family members and may provide a potential therapeutic target for diseases characterized by dysregulated B-cell activity. PMID:27956526

Immune Cells in Blood Recognize Tumors

Cancer.gov

NCI scientists have developed a novel strategy for identifying immune cells circulating in the blood that recognize specific proteins on tumor cells, a finding they believe may have potential implications for immune-based therapies.

A Novel Energy-Efficient Multi-Sensor Fusion Wake-Up Control Strategy Based on a Biomimetic Infectious-Immune Mechanism for Target Tracking.

PubMed

Zhou, Jie; Liang, Yan; Shen, Qiang; Feng, Xiaoxue; Pan, Quan

2018-04-18

A biomimetic distributed infection-immunity model (BDIIM), inspired by the immune mechanism of an infected organism, is proposed in order to achieve a high-efficiency wake-up control strategy based on multi-sensor fusion for target tracking. The resultant BDIIM consists of six sub-processes reflecting the infection-immunity mechanism: occurrence probabilities of direct-infection (DI) and cross-infection (CI), immunity/immune-deficiency of DI and CI, pathogen amount of DI and CI, immune cell production, immune memory, and pathogen accumulation under immunity state. Furthermore, a corresponding relationship between the BDIIM and sensor wake-up control is established to form the collaborative wake-up method. Finally, joint surveillance and target tracking are formulated in the simulation, in which we show that the energy cost and position tracking error are reduced to 50.8% and 78.9%, respectively. Effectiveness of the proposed BDIIM algorithm is shown, and this model is expected to have a significant role in guiding the performance improvement of multi-sensor networks.

Selective blockade of B7-H3 enhances antitumour immune activity by reducing immature myeloid cells in head and neck squamous cell carcinoma.

PubMed

Mao, Liang; Fan, Teng-Fei; Wu, Lei; Yu, Guang-Tao; Deng, Wei-Wei; Chen, Lei; Bu, Lin-Lin; Ma, Si-Rui; Liu, Bing; Bian, Yansong; Kulkarni, Ashok B; Zhang, Wen-Feng; Sun, Zhi-Jun

2017-09-01

Immature myeloid cells including myeloid-derived suppressor cells (MDSCs) and tumour-associated macrophages (TAMs) promote tumour growth and metastasis by facilitating tumour transformation and angiogenesis, as well as by suppressing antitumour effector immune responses. Therefore, strategies designed to reduce MDSCs and TAMs accumulation and their activities are potentially valuable therapeutic goals. In this study, we show that negative immune checkpoint molecule B7-H3 is significantly overexpressed in human head and neck squamous cell carcinoma (HNSCC) specimen as compared with normal oral mucosa. Using immunocompetent transgenic HNSCC models, we observed that targeting inhibition of B7-H3 reduced tumour size. Flow cytometry analysis revealed that targeting inhibition of B7-H3 increases antitumour immune response by decreasing immunosuppressive cells and promoting cytotoxic T cell activation in both tumour microenvironment and macroenvironment. Our study provides direct in vivo evidence for a rationale for B7-H3 blockade as a future therapeutic strategy to treat patients with HNSCC. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Mesenchymal Stem Cells and Myeloid Derived Suppressor Cells: Common Traits in Immune Regulation

PubMed Central

Nikolaev, Alexander

2016-01-01

To protect host against immune-mediated damage, immune responses are tightly regulated. The regulation of immune responses is mediated by various populations of mature immune cells, such as T regulatory cells and B regulatory cells, but also by immature cells of different origins. In this review, we discuss regulatory properties and mechanisms whereby two distinct populations of immature cells, mesenchymal stem cells, and myeloid derived suppressor cells mediate immune regulation, focusing on their similarities, discrepancies, and potential clinical applications. PMID:27529074

Trypanosome resistance to human innate immunity: targeting Achilles’ heel

PubMed Central

Stephens, Natalie A.; Kieft, Rudo; MacLeod, Annette; Hajduk, Stephen L.

2015-01-01

Trypanosome lytic factors (TLFs) are powerful, naturally-occurring toxins in humans that provide sterile protection against infection by several African trypanosomes. These trypanocidal complexes predominantly enter the parasite by binding to the trypanosome haptoglobin/hemoglobin receptor (HpHbR), trafficking to the lysosome, causing membrane damage and ultimately, cell lysis. Despite TLF-mediated immunity, the parasites that cause human African Trypanosomiasis (HAT), Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense, have developed independent mechanisms of resistance to TLF killing. Here we describe the parasite defenses that allow trypanosome infections of humans and discuss how targeting these apparent strengths of the parasite may reveal their Achilles’ heel, leading to new approaches in the treatment of HAT. PMID:23059119

Cutting edge: impairment of dendritic cells and adaptive immunity by Ebola and Lassa viruses.

PubMed

Mahanty, Siddhartha; Hutchinson, Karen; Agarwal, Sudhanshu; McRae, Michael; Rollin, Pierre E; Pulendran, Bali

2003-03-15

Acute infection of humans with Ebola and Lassa viruses, two principal etiologic agents of hemorrhagic fevers, often results in a paradoxical pattern of immune responses: early infection, characterized by an outpouring of inflammatory mediators such as TNF-alpha, IL-1 beta, and IL-6, vs late stage infections, which are associated with poor immune responses. The mechanisms underlying these diverse outcomes are poorly understood. In particular, the role played by cells of the innate immune system, such as dendritic cells (DC), is not known. In this study, we show that Ebola and Lassa viruses infect human monocyte-derived DC and impair their function. Monocyte-derived DC exposed to either virus fail to secrete proinflammatory cytokines, do not up-regulate costimulatory molecules, and are poor stimulators of T cells. These data represent the first evidence for a mechanism by which Ebola and Lassa viruses target DC to impair adaptive immunity.

Malondialdehyde epitopes as targets of immunity and the implications for atherosclerosis

PubMed Central

Binder, Christoph J.

2018-01-01

Accumulating evidence suggests that oxidation-specific epitopes (OSEs) constitute a novel class of damage-associated molecular patterns (DAMPs) generated during high oxidative stress but also in the physiological process of apoptosis. To deal with the potentially harmful consequences of such epitopes, the immune system has developed several mechanisms to protect from OSEs and to orchestrate their clearance, including IgM natural antibodies and both cellular and membrane-bound receptors. Here, we focus on malondialdehyde (MDA) epitopes as prominent examples of OSEs that trigger both innate and adaptive immune responses. First, we review the mechanism of MDA generation, the different types of adducts on various biomolecules and provide relevant examples for physiological carriers of MDA such as apoptotic cells, microvesicles (MV) or oxidized low-density lipoproteins (LDL). Based on recent insights, we argue that MDA epitopes contribute to the maintenance of homeostatic functions by acting as markers of elevated oxidative stress and tissue damage. We discuss multiple lines of evidence that MDA epitopes are pro-inflammatory and thus important targets of innate and adaptive immune responses. Finally, we illustrate the relevance of MDA epitopes in human pathologies by describing their capacity to drive inflammatory processes in atherosclerosis and highlighting protective mechanisms of immunity that could be exploited for therapeutic purposes. PMID:27235680

Amplifying IFN-γ Signaling in Dendritic Cells by CD11c-Specific Loss of SOCS1 Increases Innate Immunity to Infection while Decreasing Adaptive Immunity.

PubMed

Alice, Alejandro F; Kramer, Gwen; Bambina, Shelly; Baird, Jason R; Bahjat, Keith S; Gough, Michael J; Crittenden, Marka R

2018-01-01

Although prophylactic vaccines provide protective humoral immunity against infectious agents, vaccines that elicit potent CD8 T cell responses are valuable tools to shape and drive cellular immunity against cancer and intracellular infection. In particular, IFN-γ-polarized cytotoxic CD8 T cell immunity is considered optimal for protective immunity against intracellular Ags. Suppressor of cytokine signaling (SOCS)1 is a cross-functional negative regulator of TLR and cytokine receptor signaling via degradation of the receptor-signaling complex. We hypothesized that loss of SOCS1 in dendritic cells (DCs) would improve T cell responses by accentuating IFN-γ-directed immune responses. We tested this hypothesis using a recombinant Listeria monocytogenes vaccine platform that targets CD11c + DCs in mice in which SOCS1 is selectively deleted in all CD11c + cells. Unexpectedly, in mice lacking SOCS1 expression in CD11c + cells, we observed a decrease in CD8 + T cell response to the L. monocytogenes vaccine. NK cell responses were also decreased in mice lacking SOCS1 expression in CD11c + cells but did not explain the defect in CD8 + T cell immunity. We found that DCs lacking SOCS1 expression were functional in driving Ag-specific CD8 + T cell expansion in vitro but that this process was defective following infection in vivo. Instead, monocyte-derived innate TNF-α and inducible NO synthase-producing DCs dominated the antibacterial response. Thus, loss of SOCS1 in CD11c + cells skewed the balance of immune response to infection by increasing innate responses while decreasing Ag-specific adaptive responses to infectious Ags. Copyright © 2017 by The American Association of Immunologists, Inc.

Stromal cells in breast cancer as a potential therapeutic target

PubMed Central

Dykes, Samantha S.; Hughes, Veronica S.; Wiggins, Jennifer M.; Fasanya, Henrietta O.; Tanaka, Mai; Siemann, Dietmar

2018-01-01

Breast cancer in the United States is the second most commonly diagnosed cancer in women. About 1 in 8 women will develop invasive breast cancer over the course of her lifetime and breast cancer remains the second leading cause of cancer-related death. In pursuit of novel therapeutic strategies, researchers have examined the tumor microenvironment as a potential anti-cancer target. In addition to neoplastic cells, the tumor microenvironment is composed of several critical normal cell types, including fibroblasts, vascular and lymph endothelial cells, osteoclasts, adipocytes, and immune cells. These cells have important roles in healthy tissue stasis, which frequently are altered in tumors. Indeed, tumor-associated stromal cells often contribute to tumorigenesis, tumor progression, and metastasis. Consequently, these host cells may serve as a possible target in anti-tumor and anti-metastatic therapeutic strategies. Targeting the tumor associated host cells offers the benefit that such cells do not mutate and develop resistance in response to treatment, a major cause of failure in cancer therapeutics targeting neoplastic cells. This review discusses the role of host cells in the tumor microenvironment during tumorigenesis, progression, and metastasis, and provides an overview of recent developments in targeting these cell populations to enhance cancer therapy efficacy.

Effects of Food Additives on Immune Cells As Contributors to Body Weight Gain and Immune-Mediated Metabolic Dysregulation.

PubMed

Paula Neto, Heitor A; Ausina, Priscila; Gomez, Lilian S; Leandro, João G B; Zancan, Patricia; Sola-Penna, Mauro

2017-01-01

Food additives are compounds used in order to improve food palatability, texture, and shelf life. Despite a significant effort to assure safety of use, toxicological analysis of these substances, generally, rely on their direct toxicity to target organs (liver and kidney) or their genotoxic effects. Much less attention is paid to the effects of these compounds on cells of the immune system. This is of relevance given that metabolic dysregulation and obesity have a strong immune-mediated component. Obese individuals present a state of chronic low-grade inflammation that contributes to the establishment of insulin resistance and other metabolic abnormalities known as the metabolic syndrome. Obesity and metabolic syndrome are currently recognized as worldwide epidemics that pose a profound socioeconomic impact and represent a concern to public health. Cells of the immune system contribute to both the maintenance of "lean homeostasis" and the metabolic dysregulation observed in obese individuals. Although much attention has been drawn in the past decades to obesity and metabolic syndrome as a result of ingesting highly processed food containing large amounts of fat and simple sugars, mounting evidence suggest that food additives may also be important contributors to metabolic derangement. Herein, we review pieces of evidence from the literature showing that food additives have relevant effects on cells of the immune system that could contribute to immune-mediated metabolic dysregulation. Considering their potential to predispose individuals to develop obesity and metabolic syndrome, their use should be taken with caution or maybe revisited.

Microchimeric cells in systemic lupus erythematosus: targets or innocent bystanders?

PubMed

Stevens, A M

2006-01-01

During pregnancy maternal and fetal cells commute back and forth leading to fetal microchimerism in the mother and maternal microchimerism in the child that can persist for years after the birth. Chimeric fetal and maternal cells can be hematopoietic or can differentiate into somatic cells in multiple organs, potentially acting as targets for 'autoimmunity' and so have been implicated in the pathogenesis of autoimmune diseases that resemble graft-versus-host disease after stem cell transplantation. Fetal cells have been found in women with systemic lupus erythematosus, both in the blood and a target organ, the kidney, suggesting that they may be involved in pathogenesis. Future studies will address how the host immune system normally tolerates maternal and fetal cells or how the balance may change during autoimmunity.

Phosphatidylserine-targeting antibodies augment the anti-tumorigenic activity of anti-PD-1 therapy by enhancing immune activation and downregulating pro-oncogenic factors induced by T-cell checkpoint inhibition in murine triple-negative breast cancers.

PubMed

Gray, Michael J; Gong, Jian; Hatch, Michaela M S; Nguyen, Van; Hughes, Christopher C W; Hutchins, Jeff T; Freimark, Bruce D

2016-05-11

The purpose of this study was to investigate the potential of antibody-directed immunotherapy targeting the aminophospholipid phosphatidylserine, which promotes immunosuppression when exposed in the tumor microenvironment, alone and in combination with antibody treatment towards the T-cell checkpoint inhibitor PD-1 in breast carcinomas, including triple-negative breast cancers. Immune-competent mice bearing syngeneic EMT-6 or E0771 tumors were subjected to treatments comprising of a phosphatidylserine-targeting and an anti-PD-1 antibody either as single or combinational treatments. Anti-tumor effects were determined by tumor growth inhibition and changes in overall survival accompanying each treatment. The generation of a tumor-specific immune response in animals undergoing complete tumor regression was assessed by secondary tumor cell challenge and splenocyte-produced IFNγ in the presence or absence of irradiated tumor cells. Changes in the presence of tumor-infiltrating lymphocytes were assessed by flow cytometry, while mRNA-based immune profiling was determined using NanoString PanCancer Immune Profiling Panel analysis. Treatment by a phosphatidylserine-targeting antibody inhibits in-vivo growth and significantly enhances the anti-tumor activity of antibody-mediated PD-1 therapy, including providing a distinct survival advantage over treatment by either single agent. Animals in which complete tumor regression occurred with combination treatments were resistant to secondary tumor challenge and presented heightened expression levels of splenocyte-produced IFNγ. Combinational treatment by a phosphatidylserine-targeting antibody with anti-PD-1 therapy increased the number of tumor-infiltrating lymphocytes more than that observed with single-arm therapies. Finally, immunoprofiling analysis revealed that the combination of anti-phosphatidylserine targeting antibody and anti-PD-1 therapy enhanced tumor-infiltrating lymphocytes, and increased expression of pro

Epigenetic regulation of immune checkpoints: another target for cancer immunotherapy?

PubMed

Ali, Mahmoud A; Matboli, Marwa; Tarek, Marwa; Reda, Maged; Kamal, Kamal M; Nouh, Mahmoud; Ashry, Ahmed M; El-Bab, Ahmed Fath; Mesalam, Hend A; Shafei, Ayman El-Sayed; Abdel-Rahman, Omar

2017-01-01

Epigenetic changes in oncogenes and tumor-suppressor genes contribute to carcinogenesis. Understanding the epigenetic and genetic components of tumor immune evasion is crucial. Few cancer genetic mutations have been linked to direct correlations with immune evasion. Studies on the epigenetic modulation of the immune checkpoints have revealed a critical interaction between epigenetic and immune modulation. Epigenetic modifiers can activate many silenced genes. Some of them are immune checkpoints regulators that turn on immune responses and others turn them off resulting in immune evasion. Many forms of epigenetic inheritance mechanisms may play a role in regulation of immune checkpoints including: covalent modifications, noncoding RNA and histone modifications. In this review, we will show how the potential interaction between epigenetic and immune modulation may lead to new approaches for specific epigenome/immunome-targeted therapies for cancer.

Breast cancer vaccines delivered by dendritic cell-targeted lentivectors induce potent antitumor immune responses and protect mice from mammary tumor growth.

PubMed

Bryson, Paul D; Han, Xiaolu; Truong, Norman; Wang, Pin

2017-10-13

Breast cancer immunotherapy is a potent treatment option, with antibody therapies such as trastuzumab increasing 2-year survival rates by 50%. However, active immunotherapy through vaccination has generally been clinically ineffective. One potential means of improving vaccine therapy is by delivering breast cancer antigens to dendritic cells (DCs) for enhanced antigen presentation. To accomplish this in vivo, we pseudotyped lentiviral vector (LV) vaccines with a modified Sindbis Virus glycoprotein so that they could deliver genes encoding the breast cancer antigen alpha-lactalbumin (Lalba) or erb-b2 receptor tyrosine kinase 2 (ERBB2 or HER2) directly to resident DCs. We hypothesized that utilizing these DC-targeting lentiviral vectors asa breast cancer vaccine could lead to an improved immune response against self-antigens found in breast cancer tumors. Indeed, single injections of the vaccine vectors were able to amplify antigen-specific CD8T cells 4-6-fold over naïve mice, similar to the best published vaccine regimens. Immunization of these mice completely inhibited tumor growth in a foreign antigen environment (LV-ERBB2 in wildtype mice), and it reduced the rate of tumor growth in a self-antigen environment (LV-Lalba in wildtype or LV-ERBB2 in MMTV-huHER2 transgenic). These results show that a single injection with targeted lentiviral vectors can be an effective immunotherapy for breast cancer. Furthermore, they could be combined with other immunotherapeutic regimens to improve outcomes for patients with breast cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Neutrophil degranulation and immunosuppression in patients with GBM: restoration of cellular immune function by targeting arginase I.

PubMed

Sippel, Trisha R; White, Jason; Nag, Kamalika; Tsvankin, Vadim; Klaassen, Marci; Kleinschmidt-DeMasters, B K; Waziri, Allen

2011-11-15

The source of glioblastoma (GBM)-associated immunosuppression remains multifactorial. We sought to clarify and therapeutically target myeloid cell-derived peripheral immunosuppression in patients with GBM. Direct ex vivo T-cell function, serum Arginase I (ArgI) levels, and circulating myeloid lineage populations were compared between patients with GBM and normal donors or patients with other intracranial tumors. Immunofunctional assays were conducted using bulk and sorted cell populations to explore the potential transfer of myeloid cell-mediated immunosuppression and to identify a potential mechanism for these effects. ArgI-mediated immunosuppression was therapeutically targeted in vitro through pharmacologic inhibition or arginine supplementation. We identified a significantly expanded population of circulating, degranulated neutrophils associated with elevated levels of serum ArgI and decreased T-cell CD3ζ expression within peripheral blood from patients with GBM. Sorted CD11b(+) cells from patients with GBM were found to markedly suppress normal donor T-cell function in coculture, and media harvested from mitogen-stimulated GBM peripheral blood mononuclear cell (PBMC) or GBM-associated mixed lymphoid reactions showed ArgI levels that were significantly higher than controls. Critically, T-cell suppression in both settings could be completely reversed through pharmacologic ArgI inhibition or with arginine supplementation. These data indicate that peripheral cellular immunosuppression in patients with GBM is associated with neutrophil degranulation and elevated levels of circulating ArgI, and that T-cell function can be restored in these individuals by targeting ArgI. These data identify a novel pathway of GBM-mediated suppression of cellular immunity and offer a potential therapeutic window for improving antitumor immunity in affected patients.

The Role of Immune Escape and Immune Cell Infiltration in Breast Cancer.

PubMed

Steven, André; Seliger, Barbara

2018-03-01

While detailed analysis of aberrant cancer cell signaling pathways and changes in cancer cell DNA has dominated the field of breast cancer biology for years, there now exists increasing evidence that the tumor microenvironment (TME) including tumor-infiltrating immune cells support the growth and development of breast cancer and further facilitate invasion and metastasis formation as well as sensitivity to drug therapy. Furthermore, breast cancer cells have developed different strategies to escape surveillance from the adaptive and innate immune system. These include loss of expression of immunostimulatory molecules, gain of expression of immunoinhibitory molecules such as PD-L1 and HLA-G, and altered expression of components involved in apoptosis. Furthermore, the composition of the TME plays a key role in breast cancer development and treatment response. In this review we will focus on i) the different immune evasion mechanisms used by breast cancer cells, ii) the role of immune cell infiltration in this disease, and (iii) implication for breast cancer-based immunotherapies.

A Critical Role for the TLR4/TRIF Pathway in Allogeneic Hematopoietic Cell Rejection by Innate Immune Cells

PubMed Central

Xu, Hong; Yan, Jun; Zhu, Ziqiang; Hussain, Lala-Rukh; Huang, Yiming; Ding, Chuanlin; Bozulic, Larry D.; Wen, Yujie; Ildstad, Suzanne T.

2013-01-01

We show for the first time that signaling through the TLR4/TRIF pathway plays a critical role in allogeneic bone marrow cell (BMC) rejection. This appears to be unique to BMC as organ allografts are rejected mainly via MyD88 signaling. Using T or T/B cell-deficient mice, we found that BMC allorejection occurred early before T cell activation and was T and B cell-independent, suggesting an effector role for innate immune cells in BMC rejection. We further demonstrated the innate immune signaling in BMC allorejection by showing superior engraftment in mice deficient in TRIF or TLR4 but not MyD88 or TLR3. The restored cytotoxicity in TRIF deficient recipients transferred with wildtype F4/80+ or NK1.1+ cells suggests TRIF signaling dependence on macrophages or NK cells in early BMC rejection. Production of the proinflammatory cytokine IL-6 and TRIF relevant chemokine MCP-1 was significantly increased early after bone marrow transplantation. In vivo specific depletion of macrophages or NK innate immune cells in combination with anti-CD154/rapamycin resulted in additive-enhanced allogeneic engraftment. The requirement for irradiation was completely eliminated when both macrophages and NK cells were depleted in combination with anti-CD154/rapamycin to target T and B cells, supporting the hypothesis that two barriers involving innate and adaptive immunity exist in mediating rejection of allogeneic BMC. In summary, our results clearly demonstrate a previously unappreciated role for innate immunity in BMC allorejection via signaling through a unique MyD88-independent TLR4/TRIF mechanism. These findings may have direct clinical impact on strategies for conditioning recipients for stem cell transplantation. PMID:23146386

NK cells influence both innate and adaptive immune responses after mucosal immunisation with antigen and mucosal adjuvant*

PubMed Central

Hall, Lindsay J; Clare, Simon; Dougan, Gordon

2012-01-01

NK cells were found to be recruited in a temporally controlled manner to the nasal-associated lymphoid tissue and the cervical lymph nodes of mice following intranasal immunisation with Ag85B-ESAT6 antigen from Mycobacterium tuberculosis mixed with Escherichia coli heat-labile toxin as adjuvant. These NK cells were activated and they secreted a diverse range of cytokines and other immunmodulators. Using antibody depletion targeting anti-asialo GM1, we found evidence for altered trafficking, impaired activation and cytokine secretion of dendritic cells, macrophages and neutrophils in immunised NK cell depleted mice compared to control animals. Analysis of antigen-specific immune responses revealed an attenuated antibody and cytokine response in immunised NK cell depleted animals. Systemic administration of rIL-6 but not rIFN-γ significantly restored immune responses in mice depleted of NK cells. In conclusion, cytokine production, particularly IL-6, via NK cells and NK cell activated immune populations, plays an important role in the establishment of local innate immune responses and the consequent development of adaptive immunity after mucosal immunisation. PMID:20220095

Allelic Dependent Expression of an Activating Fc receptor on B cells Enhances Humoral Immune Responses

PubMed Central

Li, Xinrui; Wu, Jianming; Ptacek, Travis; Redden, David T; Brown, Elizabeth E; Alarcón, Graciela S; Ramsey-Goldman, Rosalind; Petri, Michelle A; Reveille, John D.; Kaslow, Richard A; Kimberly, Robert P; Edberg, Jeffrey C

2014-01-01

B cells are pivotal regulators of acquired immune responses and recent work in both experimental murine models and humans has demonstrated that subtle changes in the regulation of B cell function can significantly alter immunological responses. The balance of negative and positive signals in maintaining an appropriate B cell activation threshold is critical in B lymphocyte immune tolerance and autoreactivity. FcγRIIb (CD32B), the only recognized Fcγ receptor on B cells, provides IgG-mediated negative modulation through a tyrosine-based inhibition motif which down-regulates B cell receptor initiated signaling. These properties make FcγRIIb a promising target for antibody-based therapy. Here we report the discovery of allele-dependent expression of the activating FcγRIIc on B cells. Identical to FcγRIIb in the extracellular domain, FcγRIIc has a tyrosine-based activation motif in its cytoplasmic domain. In both human B cells and in B cells from mice transgenic for human FcγRIIc, FcγRIIc expression counterbalances the negative feedback of FcγRIIb and enhances humoral responses to immunization in mice and to BioThrax® vaccination in a human Anthrax vaccine trial. Moreover, the FCGR2C-ORF allele is associated with the risk of development of autoimmunity in humans. FcγRIIc expression on B cells challenges the prevailing paradigm of uni-directional negative feedback by IgG immune complexes via the inhibitory FcγRIIb, is a previously unrecognized determinant in human antibody/autoantibody responses, and opens the opportunity for more precise personalized use of B cell targeted antibody-based therapy. PMID:24353158

Sterile Immunity to Malaria after DNA Prime/Adenovirus Boost Immunization Is Associated with Effector Memory CD8+T Cells Targeting AMA1 Class I Epitopes

PubMed Central

Sedegah, Martha; Hollingdale, Michael R.; Farooq, Fouzia; Ganeshan, Harini; Belmonte, Maria; Kim, Yohan; Peters, Bjoern; Sette, Alessandro; Huang, Jun; McGrath, Shannon; Abot, Esteban; Limbach, Keith; Shi, Meng; Soisson, Lorraine; Diggs, Carter; Chuang, Ilin; Tamminga, Cindy; Epstein, Judith E.; Villasante, Eileen; Richie, Thomas L.

2014-01-01

Background Fifteen volunteers were immunized with three doses of plasmid DNA encoding P. falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1) and boosted with human adenovirus-5 (Ad) expressing the same antigens (DNA/Ad). Four volunteers (27%) demonstrated sterile immunity to controlled human malaria infection and, overall, protection was statistically significantly associated with ELISpot and CD8+ T cell IFN-γ activities to AMA1 but not CSP. DNA priming was required for protection, as 18 additional subjects immunized with Ad alone (AdCA) did not develop sterile protection. Methodology/Principal Findings We sought to identify correlates of protection, recognizing that DNA-priming may induce different responses than AdCA alone. Among protected volunteers, two and three had higher ELISpot and CD8+ T cell IFN-γ responses to CSP and AMA1, respectively, than non-protected volunteers. Unexpectedly, non-protected volunteers in the AdCA trial showed ELISpot and CD8+ T cell IFN-γ responses to AMA1 equal to or higher than the protected volunteers. T cell functionality assessed by intracellular cytokine staining for IFN-γ, TNF-α and IL-2 likewise did not distinguish protected from non-protected volunteers across both trials. However, three of the four protected volunteers showed higher effector to central memory CD8+ T cell ratios to AMA1, and one of these to CSP, than non-protected volunteers for both antigens. These responses were focused on discrete regions of CSP and AMA1. Class I epitopes restricted by A*03 or B*58 supertypes within these regions of AMA1 strongly recalled responses in three of four protected volunteers. We hypothesize that vaccine-induced effector memory CD8+ T cells recognizing a single class I epitope can confer sterile immunity to P. falciparum in humans. Conclusions/Significance We suggest that better understanding of which epitopes within malaria antigens can confer sterile immunity and design of vaccine approaches

MHC-matched induced pluripotent stem cells can attenuate cellular and humoral immune responses but are still susceptible to innate immunity in pigs.

PubMed

Mizukami, Yoshihisa; Abe, Tomoyuki; Shibata, Hiroaki; Makimura, Yukitoshi; Fujishiro, Shuh-hei; Yanase, Kimihide; Hishikawa, Shuji; Kobayashi, Eiji; Hanazono, Yutaka

2014-01-01

Recent studies have revealed negligible immunogenicity of induced pluripotent stem (iPS) cells in syngeneic mice and in autologous monkeys. Therefore, human iPS cells would not elicit immune responses in the autologous setting. However, given that human leukocyte antigen (HLA)-matched allogeneic iPS cells would likely be used for medical applications, a more faithful model system is needed to reflect HLA-matched allogeneic settings. Here we examined whether iPS cells induce immune responses in the swine leukocyte antigen (SLA)-matched setting. iPS cells were generated from the SLA-defined C1 strain of Clawn miniature swine, which were confirmed to develop teratomas in mice, and transplanted into the testes (n = 4) and ovary (n = 1) of C1 pigs. No teratomas were found in pigs on 47 to 125 days after transplantation. A Mixed lymphocyte reaction revealed that T-cell responses to the transplanted MHC-matched (C1) iPS cells were significantly lower compared to allogeneic cells. The humoral immune responses were also attenuated in the C1-to-C1 setting. More importantly, even MHC-matched iPS cells were susceptible to innate immunity, NK cells and serum complement. iPS cells lacked the expression of SLA class I and sialic acids. The in vitro cytotoxic assay showed that C1 iPS cells were targeted by NK cells and serum complement of C1. In vivo, the C1 iPS cells developed larger teratomas in NK-deficient NOG (T-B-NK-) mice (n = 10) than in NK-competent NOD/SCID (T-B-NK+) mice (n = 8) (p<0.01). In addition, C1 iPS cell failed to form teratomas after incubation with the porcine complement-active serum. Taken together, MHC-matched iPS cells can attenuate cellular and humoral immune responses, but still susceptible to innate immunity in pigs.

The immune system: a target for functional foods?

PubMed

Calder, Philip C; Kew, Samantha

2002-11-01

The immune system acts to protect the host from infectious agents that exist in the environment (bacteria, viruses, fungi, parasites) and from other noxious insults. The immune system is constantly active, acting to discriminate 'non-self' from 'self'. The immune system has two functional divisions: the innate and the acquired. Both components involve various blood-borne factors (complement, antibodies, cytokines) and cells. A number of methodologies exist to assess aspects of immune function; many of these rely upon studying cells in culture ex vivo. There are large inter-individual variations in many immune functions even among the healthy. Genetics, age, gender, smoking habits, habitual levels of exercise, alcohol consumption, diet, stage in the female menstrual cycle, stress, history of infections and vaccinations, and early life experiences are likely to be important contributors to the observed variation. While it is clear that individuals with immune responses significantly below 'normal' are more susceptible to infectious agents and exhibit increased infectious morbidity and mortality, it is not clear how the variation in immune function among healthy individuals relates to variation in susceptibility to infection. Nutrient status is an important factor contributing to immune competence: undernutrition impairs the immune system, suppressing immune functions that are fundamental to host protection. Undernutrition leading to impairment of immune function can be due to insufficient intake of energy and macronutrients and/or due to deficiencies in specific micronutrients. Often these occur in combination. Nutrients that have been demonstrated (in either animal or human studies) to be required for the immune system to function efficiently include essential amino acids, the essential fatty acid linoleic acid, vitamin A, folic acid, vitamin B6, vitamin B12, vitamin C, vitamin E, Zn, Cu, Fe and Se. Practically all forms of immunity may be affected by deficiencies

Targeting programmed cell death ligand 1 by CRISPR/Cas9 in osteosarcoma cells

PubMed Central

Liao, Yunfei; Chen, Lulu; Feng, Yong; Shen, Jacson; Gao, Yan; Cote, Gregory; Choy, Edwin; Harmon, David; Mankin, Henry; Hornicek, Francis; Duan, Zhenfeng

2017-01-01

Programmed cell death ligand 1 (PD-L1) is a transmembrane protein that is expressed on tumor cells that suppresses the T cell-mediated immune response. Therapies targeting the PD-L1 pathway promote anti-tumor immunity and have shown promising results in some types of cancers. However, the functional and therapeutic roles of PD-L1 in osteosarcoma remain largely unknown. In this study, we found that PD-L1 protein was expressed in osteosarcoma cell lines and tissue microarray of patient tumors. Tissue microarray immunohistochemistry analysis showed that the overall and five-year survival rates of patients with high levels of PD-L1 expression were significantly shorter than patients with low levels. High levels of PD-L1 expression were also associated with metastasis in osteosarcoma patients. Furthermore, we applied the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 system to target PD-L1 gene at the DNA level in osteosarcoma cell lines. We found that the expression of PD-L1 could be efficiently disrupted by CRISPR/Cas9 system and PD-L1 knockdown increased drug sensitivities for doxorubicin and paclitaxel. These results suggest that PD-L1 is an independent prognostic factor in osteosarcoma and that PD-L1 knockout by CRISPR/Cas9 may be a therapeutic approach for the treatment of osteosarcoma. PMID:28415820

Targeting programmed cell death ligand 1 by CRISPR/Cas9 in osteosarcoma cells.

PubMed

Liao, Yunfei; Chen, Lulu; Feng, Yong; Shen, Jacson; Gao, Yan; Cote, Gregory; Choy, Edwin; Harmon, David; Mankin, Henry; Hornicek, Francis; Duan, Zhenfeng

2017-05-02

Programmed cell death ligand 1 (PD-L1) is a transmembrane protein that is expressed on tumor cells that suppresses the T cell-mediated immune response. Therapies targeting the PD-L1 pathway promote anti-tumor immunity and have shown promising results in some types of cancers. However, the functional and therapeutic roles of PD-L1 in osteosarcoma remain largely unknown. In this study, we found that PD-L1 protein was expressed in osteosarcoma cell lines and tissue microarray of patient tumors. Tissue microarray immunohistochemistry analysis showed that the overall and five-year survival rates of patients with high levels of PD-L1 expression were significantly shorter than patients with low levels. High levels of PD-L1 expression were also associated with metastasis in osteosarcoma patients. Furthermore, we applied the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 system to target PD-L1 gene at the DNA level in osteosarcoma cell lines. We found that the expression of PD-L1 could be efficiently disrupted by CRISPR/Cas9 system and PD-L1 knockdown increased drug sensitivities for doxorubicin and paclitaxel. These results suggest that PD-L1 is an independent prognostic factor in osteosarcoma and that PD-L1 knockout by CRISPR/Cas9 may be a therapeutic approach for the treatment of osteosarcoma.

Platelets Subvert T Cell Immunity Against Cancer via GARP-TGFβ Axis

PubMed Central

Rachidi, Saleh; Metelli, Alessandra; Riesenberg, Brian; Wu, Bill X; Nelson, Michelle H; Fugle, Caroline W; Paulos, Chrystal M; Rubinstein, Mark P; Garrett-Mayer, Elizabeth; Hennig, Mirko; Bearden, Daniel W; Yang, Yi; Liu, Bei; Li, Zihai

2017-01-01

Cancer-associated thrombocytosis has long been linked to poor clinical outcome, but the underlying mechanism is enigmatic. We hypothesized that platelets promote malignancy and resistance to therapy by dampening host immunity. We herein show that genetic targeting of platelets significantly enhances adoptive T cell therapy of cancer. An unbiased biochemical and structural biology approach established transforming growth factor β (TGFβ) and lactate as the major platelet-derived soluble factors to obliterate CD4+ and CD8+ T cell functions. Moreover, we found that platelets are the dominant source of functional TGFβ systemically as well as in the tumor microenvironment through constitutive expression of TGFβ-docking receptor Glycoprotein A Repetitions Predominant (GARP) rather than secretion of TGFβ per se. Indeed, platelet-specific deletion of GARP-encoding gene Lrrc32 blunted TGFβ activity at the tumor site and potentiated protective immunity against both melanoma and colon cancer. Finally, we found that T cell therapy of cancer can be substantially improved by concurrent treatment with readily available anti-platelet agents. We conclude that platelets constrain T cell immunity though a GARP-TGFβ axis and suggest a combination of immunotherapy and platelet inhibitors as a therapeutic strategy against cancer. PMID:28763790

Regulatory roles of mast cells in immune responses.

PubMed

Morita, Hideaki; Saito, Hirohisa; Matsumoto, Kenji; Nakae, Susumu

2016-09-01

Mast cells are important immune cells for host defense through activation of innate immunity (via toll-like receptors or complement receptors) and acquired immunity (via FcεRI). Conversely, mast cells also act as effector cells that exacerbate development of allergic or autoimmune disorders. Yet, several lines of evidence show that mast cells act as regulatory cells to suppress certain inflammatory diseases. Here, we review the mechanisms by which mast cells suppress diseases.

Exosomes and nanotubes: control of immune cell communication

PubMed Central

McCoy-Simandle, Kessler; Hanna, Samer J.; Cox, Dianne

2015-01-01

Cell-cell communication is critical to coordinate the activity and behavior of a multicellular organism. The cells of the immune system not only must communicate with similar cells, but also with many other cell types in the body. Therefore, the cells of the immune system have evolved multiple ways to communicate. Exosomes and tunneling nanotubes (TNTs) are two means of communication used by immune cells that contribute to immune functions. Exosomes are small membrane vesicles secreted by most cell types that can mediate intercellular communication and in the immune system they are proposed to play a role in antigen presentation and modulation of gene expression. TNTs are membranous structures that mediate direct cell-cell contact over several cell diameters in length (and possibly longer) and facilitate the interaction and/or the transfer of signals, material and other cellular organelles between connected cells. Recent studies have revealed additional, but sometimes conflicting, structural and functional features of both exosomes and TNTs. Despite the new and exciting information in exosome and TNT composition, origin and in vitro function, biologically significant functions are still being investigated and determined. In this review, we discuss the current field regarding exosomes and TNTs in immune cells providing evaluation and perspectives of the current literature. PMID:26704468

An identical miRNA of the human JC and BK polyoma viruses targets the stress-induced ligand ULBP3 to escape immune elimination.

PubMed

Bauman, Yoav; Nachmani, Daphna; Vitenshtein, Alon; Tsukerman, Pinchas; Drayman, Nir; Stern-Ginossar, Noam; Lankry, Dikla; Gruda, Raizy; Mandelboim, Ofer

2011-02-17

The human polyoma viruses JCV and BKV establish asymptomatic persistent infection in 65%-90% of humans but can cause severe illness under immunosuppressive conditions. The mechanisms by which these viruses evade immune recognition are unknown. Here we show that a viral miRNA identical in sequence between JCV and BKV targets the stress-induced ligand ULBP3, which is a protein recognized by the killer receptor NKG2D. Consequently, viral miRNA-mediated ULBP3 downregulation results in reduced NKG2D-mediated killing of virus-infected cells by natural killer (NK) cells. Importantly, when the activity of the viral miRNA was inhibited during infection, NK cells killed the infected cells more efficiently. Because NKG2D is also expressed by various T cell subsets, we propose that JCV and BKV use an identical miRNA that targets ULBP3 to escape detection by both the innate and adaptive immune systems, explaining how these viruses remain latent without being eliminated by the immune system. Copyright © 2011 Elsevier Inc. All rights reserved.

Stroma: the forgotten cells of innate immune memory.

PubMed

Crowley, Thomas; Buckley, Christopher D; Clark, Andrew R

2018-05-05

All organisms are constantly exposed to a variety of infectious and injurious stimuli. These induce inflammatory responses tailored to the threat posed. Whilst the innate immune system is the front line of response to each stimulant, it has been traditionally considered to lack memory, acting in a generic fashion until the adaptive immune arm can take over. This outmoded simplification of the roles of innate and acquired arms of the immune system has been challenged by evidence of myeloid cells altering their response to subsequent encounters based on earlier exposure. This concept of "innate immune memory" has been known for nearly a century, and is accepted amongst myeloid biologists. In recent years, other innate immune cells, such as natural killer cells, have been shown to display memory, suggesting innate immune memory is a trait common to several cell types. Over the last thirty years, evidence has slowly accumulated in favour of not only haematopoietic cells, but also stromal cells, being imbued with memory following inflammatory episodes. A recent publication showing this also to be true in epithelial cells suggests innate immune memory to be widespread, if underappreciated, in non-haematopoietic cells. In this review, we will examine the evidence supporting the existence of innate immune memory in stromal cells. We will also discuss the ramifications of memory in long-lived tissue-resident cells. Finally, we will pose questions we feel to be important in the understanding of these forgotten cells in the field of innate memory. This article is protected by copyright. All rights reserved. © 2018 British Society for Immunology.

Simultaneous Vascular Targeting and Tumor Targeting of Cerebral Breast Cancer Metastases Using a T-Cell Receptor Mimic Antibody

DTIC Science & Technology

2014-05-01

in May 2013, the difference between nude mice (which lack T- cells , but still have a partially functional adaptive and innate immune system) and NSG...Mangada J, Greiner DL, Handgretinger R. Human lymphoid and myeloid cell development in NOD/LtSz-scid IL2R gamma null mice engrafted with mobilized human...Targeting of Cerebral Breast Cancer Metastases Using a T- Cell Receptor Mimic Antibody PRINCIPAL INVESTIGATOR: Ulrich Bickel

Interlesional diversity of T cell receptors in melanoma with immune checkpoints enriched in tissue-resident memory T cells

PubMed Central

Boddupalli, Chandra Sekhar; Bar, Noffar; Kadaveru, Krishna; Krauthammer, Michael; Pornputtapong, Natopol; Ariyan, Stephan; Narayan, Deepak; Kluger, Harriet; Deng, Yanhong; Verma, Rakesh; Das, Rituparna; Bacchiocchi, Antonella; Halaban, Ruth; Sznol, Mario; Dhodapkar, Madhav V.; Dhodapkar, Kavita M.

2016-01-01

Heterogeneity of tumor cells and their microenvironment can affect outcome in cancer. Blockade of immune checkpoints (ICPs) expressed only on a subset of immune cells leads to durable responses in advanced melanoma. Tissue-resident memory T (TRM) cells have recently emerged as a distinct subset of memory T cells in nonlymphoid tissues. Here, we show that functional properties and expression of ICPs within tumor-infiltrating lymphocytes (TILs) differ from those of blood T cells. TILs secrete less IL-2, IFN-γ, and TNF-α compared with circulating counterparts, and expression of VEGF correlated with reduced TIL infiltration. Within tumors, ICPs are particularly enriched within T cells with phenotype and genomic features of TRM cells and the CD16+ subset of myeloid cells. Concurrent T cell receptor (TCR) and tumor exome sequencing of individual metastases in the same patient revealed that interlesional diversity of TCRs exceeded differences in mutation/neoantigen load in tumor cells. These findings suggest that the TRM subset of TILs may be the major target of ICP blockade and illustrate interlesional diversity of tissue-resident TCRs within individual metastases, which did not equilibrate between metastases and may differentially affect the outcome of immune therapy at each site. PMID:28018970

Liver cell-targeted delivery of therapeutic molecules.

PubMed

Kang, Jeong-Hun; Toita, Riki; Murata, Masaharu

2016-01-01

The liver is the largest internal organ in mammals and is involved in metabolism, detoxification, synthesis of proteins and lipids, secretion of cytokines and growth factors and immune/inflammatory responses. Hepatitis, alcoholic or non-alcoholic liver disease, hepatocellular carcinoma, hepatic veno-occlusive disease, and liver fibrosis and cirrhosis are the most common liver diseases. Safe and efficient delivery of therapeutic molecules (drugs, genes or proteins) into the liver is very important to increase the clinical efficacy of these molecules and to reduce their side effects in other organs. Several liver cell-targeted delivery systems have been developed and tested in vivo or ex vivo/in vitro. In this review, we discuss the literature concerning liver cell-targeted delivery systems, with a particular emphasis on the results of in vivo studies.

Antitumor immunity and cancer stem cells.

PubMed

Schatton, Tobias; Frank, Markus H

2009-09-01

Self-renewing cancer stem cells (CSC) capable of spawning more differentiated tumor cell progeny are required for tumorigenesis and neoplastic progression of leukemias and several solid cancers. The mechanisms by which CSC cause tumor initiation and growth are currently unknown. Recent findings that suggest a negative correlation between degrees of host immunocompetence and rates of cancer development raise the possibility that only a restricted minority of malignant cells, namely CSC, may possess the phenotypic and functional characteristics to evade host antitumor immunity. In human malignant melanoma, a highly immunogenic cancer, we recently identified malignant melanoma initiating cells (MMIC), a novel type of CSC, based on selective expression of the chemoresistance mediator ABCB5. Here we present evidence of a relative immune privilege of ABCB5(+) MMIC, suggesting refractoriness to current immunotherapeutic treatment strategies. We discuss our findings in the context of established immunomodulatory functions of physiologic stem cells and in relation to mechanisms responsible for the downregulation of immune responses against tumors. We propose that the MMIC subset might be responsible for melanoma immune evasion and that immunomodulation might represent one mechanism by which CSC advance tumorigenic growth and resistance to immunotherapy. Accordingly, the possibility of an MMIC-driven tumor escape from immune-mediated rejection has important implications for current melanoma immunotherapy.

Antitumor Immunity and Cancer Stem Cells

PubMed Central

Schatton, Tobias; Frank, Markus H.

2010-01-01

Self-renewing cancer stem cells (CSC) capable of spawning more differentiated tumor cell progeny are required for tumorigenesis and neoplastic progression of leukemias and several solid cancers. The mechanisms by which CSC cause tumor initiation and growth are currently unknown. Recent findings that suggest a negative correlation between degrees of host immunocompetence and rates of cancer development raise the possibility that only a restricted minority of malignant cells, namely CSC, may possess the phenotypic and functional characteristics to evade host antitumor immunity. In human malignant melanoma, a highly immunogenic cancer, we recently identified malignant melanoma initiating cells (MMIC), a novel type of CSC, based on selective expression of the chemoresistance mediator ABCB5. Here we present evidence of a relative immune privilege of ABCB5+ MMIC, suggesting refractoriness to current immunotherapeutic treatment strategies. We discuss our findings in the context of established immunomodulatory functions of physiologic stem cells and in relation to mechanisms responsible for the downregulation of immune responses against tumors. We propose that the MMIC subset might be responsible for melanoma immune evasion and that immunomodulation might represent one mechanism by which CSC advance tumorigenic growth and resistance to immunotherapy. Accordingly, the possibility of an MMIC-driven tumor escape from immune-mediated rejection has important implications for current melanoma immunotherapy. PMID:19796244

Cas9-mediated targeting of viral RNA in eukaryotic cells.

PubMed

Price, Aryn A; Sampson, Timothy R; Ratner, Hannah K; Grakoui, Arash; Weiss, David S

2015-05-12

Clustered, regularly interspaced, short palindromic repeats-CRISPR associated (CRISPR-Cas) systems are prokaryotic RNA-directed endonuclease machineries that act as an adaptive immune system against foreign genetic elements. Using small CRISPR RNAs that provide specificity, Cas proteins recognize and degrade nucleic acids. Our previous work demonstrated that the Cas9 endonuclease from Francisella novicida (FnCas9) is capable of targeting endogenous bacterial RNA. Here, we show that FnCas9 can be directed by an engineered RNA-targeting guide RNA to target and inhibit a human +ssRNA virus, hepatitis C virus, within eukaryotic cells. This work reveals a versatile and portable RNA-targeting system that can effectively function in eukaryotic cells and be programmed as an antiviral defense.

Cas9-mediated targeting of viral RNA in eukaryotic cells

PubMed Central

Price, Aryn A.; Sampson, Timothy R.; Ratner, Hannah K.; Grakoui, Arash; Weiss, David S.

2015-01-01

Clustered, regularly interspaced, short palindromic repeats–CRISPR associated (CRISPR-Cas) systems are prokaryotic RNA-directed endonuclease machineries that act as an adaptive immune system against foreign genetic elements. Using small CRISPR RNAs that provide specificity, Cas proteins recognize and degrade nucleic acids. Our previous work demonstrated that the Cas9 endonuclease from Francisella novicida (FnCas9) is capable of targeting endogenous bacterial RNA. Here, we show that FnCas9 can be directed by an engineered RNA-targeting guide RNA to target and inhibit a human +ssRNA virus, hepatitis C virus, within eukaryotic cells. This work reveals a versatile and portable RNA-targeting system that can effectively function in eukaryotic cells and be programmed as an antiviral defense. PMID:25918406

The cell-mediated immunity of Drosophila melanogaster: hemocyte lineages, immune compartments, microanatomy and regulation.

PubMed

Honti, Viktor; Csordás, Gábor; Kurucz, Éva; Márkus, Róbert; Andó, István

2014-01-01

In the animal kingdom, innate immunity is the first line of defense against invading pathogens. The dangers of microbial and parasitic attacks are countered by similar mechanisms, involving the prototypes of the cell-mediated immune responses, the phagocytosis and encapsulation. Work on Drosophila has played an important role in promoting an understanding of the basic mechanisms of phylogenetically conserved modules of innate immunity. The aim of this review is to survey the developments in the identification and functional definition of immune cell types and the immunological compartments of Drosophila melanogaster. We focus on the molecular and developmental aspects of the blood cell types and compartments, as well as the dynamics of blood cell development and the immune response. Further advances in the characterization of the innate immune mechanisms in Drosophila will provide basic clues to the understanding of the importance of the evolutionary conserved mechanisms of innate immune defenses in the animal kingdom. Copyright © 2013 Elsevier Ltd. All rights reserved.

Endothelial cells: From innocent bystanders to active participants in immune responses.

PubMed

Al-Soudi, A; Kaaij, M H; Tas, S W

2017-09-01

The endothelium is crucially important for the delivery of oxygen and nutrients throughout the body under homeostatic conditions. However, it also contributes to pathology, including the initiation and perpetuation of inflammation. Understanding the function of endothelial cells (ECs) in inflammatory diseases and molecular mechanisms involved may lead to novel approaches to dampen inflammation and restore homeostasis. In this article, we discuss the various functions of ECs in inflammation with a focus on pathological angiogenesis, attraction of immune cells, antigen presentation, immunoregulatory properties and endothelial-to-mesenchymal transition (EndMT). We also review the current literature on approaches to target these processes in ECs to modulate immune responses and advance anti-inflammatory therapies. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Anti-EGFR Targeted Monoclonal Antibody Isotype Influences Antitumor Cellular Immunity in Head and Neck Cancer Patients.

PubMed

Trivedi, Sumita; Srivastava, Raghvendra M; Concha-Benavente, Fernando; Ferrone, Soldano; Garcia-Bates, Tatiana M; Li, Jing; Ferris, Robert L

2016-11-01

EGF receptor (EGFR) is highly overexpressed on several cancers and two targeted anti-EGFR antibodies which differ by isotype are FDA-approved for clinical use. Cetuximab (IgG1 isotype) inhibits downstream signaling of EGFR and activates antitumor, cellular immune mechanisms. As panitumumab (IgG2 isotype) may inhibit downstream EGFR signaling similar to cetuximab, it might also induce adaptive immunity. We measured in vitro activation of cellular components of the innate and adaptive immune systems. We also studied the in vivo activation of components of the adaptive immune system in patient specimens from two recent clinical trials using cetuximab or panitumumab. Both monoclonal antibodies (mAb) primarily activate natural killer (NK) cells, although cetuximab is significantly more potent than panitumumab. Cetuximab-activated neutrophils mediate antibody-dependent cellular cytotoxicity (ADCC) against head and neck squamous cell carcinomas (HNSCC) tumor cells, and interestingly, this effect was FcγRIIa- and FcγRIIIa genotype-dependent. Panitumumab may activate monocytes through CD32 (FcγRIIa); however, monocytes activated by either mAb are not able to mediate ADCC. Cetuximab enhanced dendritic cell (DC) maturation to a greater extent than panitumumab, which was associated with improved tumor antigen cross-presentation by cetuximab compared with panitumumab. This correlated with increased EGFR-specific cytotoxic CD8 + T cells in patients treated with cetuximab compared with those treated with panitumumab. Although panitumumab effectively inhibits EGFR signaling to a similar extent as cetuximab, it is less effective at triggering antitumor, cellular immune mechanisms which may be crucial for effective therapy of HNSCC. Clin Cancer Res; 22(21); 5229-37. ©2016 AACR. ©2016 American Association for Cancer Research.

5'-Triphosphate siRNA targeting MDR1 reverses multi-drug resistance and activates RIG-I-induced immune-stimulatory and apoptotic effects against human myeloid leukaemia cells.

PubMed

Li, Dengzhe; Gale, Robert Peter; Liu, Yanfeng; Lei, Baoxia; Wang, Yuan; Diao, Dongmei; Zhang, Mei

2017-07-01

Multi-drug resistance (MDR), immune suppression and decreased apoptosis are important causes of therapy-failure in leukaemia. Short interfering RNAs (siRNAs) down-regulate gene transcription, have sequence-independent immune-stimulatory effects and synergize with other anti-cancer therapies in some experimental models. We designed a siRNA targeting MDR1 with 5'-triphosphate ends (3p-siRNA-MDR1). Treatment of leukaemia cells with 3p-siRNA-MDR1 down-regulated MDR1 expression, reduced-drug resistance and induced immune and pro-apoptotic effects in drug-resistant HL-60/Adr and K562/Adr human leukaemia cell lines. We show mechanisms-of-action of these effects involve alterations in the anti-viral cytosolic retinoic acid-inducible protein-I (RIG-I; encoded by RIG-I or DDX58) mediated type-I interferon signal induction, interferon-gamma-inducible protein 10 (IP-10; encoded by IP10 or CXCL10) secretion, major histocompatibility complex-I expression (MHC-I) and caspase-mediated cell apoptosis. 3p-siRNA-MDR1 transfection also enhanced the anti-leukaemia efficacy of doxorubicin. These data suggest a possible synergistic role for 3p-siRNA-MDR1 in anti-leukaemia therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cell-to-cell transmission of retroviruses: Innate immunity and interferon-induced restriction factors

PubMed Central

Jolly, Clare

2011-01-01

It has been known for some time that retroviruses can disseminate between immune cells either by conventional cell-free transmission or by directed cell-to-cell spread. Over the past few years there has been increasing interest in how retroviruses may use cell-to-cell spread to promote more rapid infection kinetics and circumvent humoral immunity. Effective humoral immune responses are intimately linked with innate immunity and the interplay between retroviruses and innate immunity is a rapidly expanding area of research that has been advanced considerably by the identification of cellular restriction factors that provide barriers to retroviral infection. The effect of innate immunity and restriction factors on retroviral cell-to-cell spread has been comparatively little studied; however recent work suggests this maybe changing. Here I will review some recent advances in what is a budding area of retroviral research. PMID:21247613

Natural killer cells regulate T cell immune responses in primary biliary cirrhosis.

PubMed

Shimoda, Shinji; Hisamoto, Satomi; Harada, Kenichi; Iwasaka, Sho; Chong, Yong; Nakamura, Minoru; Bekki, Yuki; Yoshizumi, Tomoharu; Shirabe, Ken; Ikegami, Toru; Maehara, Yoshihiko; He, Xiao-Song; Gershwin, M Eric; Akashi, Koichi

2015-12-01

The hallmark of primary biliary cirrhosis (PBC) is the presence of autoreactive T- and B-cell responses that target biliary epithelial cells (BECs). Biliary cell cytotoxicity is dependent upon initiation of innate immune responses followed by chronic adaptive, as well as bystander, mechanisms. Critical to these mechanisms are interactions between natural killer (NK) cells and BECs. We have taken advantage of the ability to isolate relatively pure viable preparations of liver-derived NK cells, BECs, and endothelial cells, and studied interactions between NK cells and BECs and focused on the mechanisms that activate autoreactive T cells, their dependence on interferon (IFN)-γ, and expression of BEC major histocompatibility complex (MHC) class I and II molecules. Here we show that at a high NK/BEC ratio, NK cells are cytotoxic for autologous BECs, but are not dependent on autoantigen, yet still activate autoreactive CD4(+) T cells in the presence of antigen presenting cells. In contrast, at a low NK/BEC ratio, BECs are not lysed, but IFN-γ production is induced, which facilitates expression of MHC class I and II molecules on BEC and protects them from lysis upon subsequent exposure to autoreactive NK cells. Furthermore, IFN-γ secreted from NK cells after exposure to autologous BECs is essential for this protective function and enables autoreactive CD4(+) T cells to become cytopathic. NK cell-mediated innate immune responses are likely critical at the initial stage of PBC, but also facilitate and maintain the chronic cytopathic effect of autoantigen-specific T cells, essential for progression of disease. © 2015 by the American Association for the Study of Liver Diseases.

Alterations of immune response of non-small cell lung cancer with Azacytidine

PubMed Central

Easwaran, Hariharan; Mohammad, Helai P.; Vendetti, Frank; VanCriekinge, Wim; DeMeyer, Tim; Du, Zhengzong; Parsana, Princy; Rodgers, Kristen; Yen, Ray-Whay; Zahnow, Cynthia A.; Taube, Janis M.; Brahmer, Julie R.; Tykodi, Scott S.; Easton, Keith; Carvajal, Richard D.; Jones, Peter A.; Laird, Peter W.; Weisenberger, Daniel J.; Tsai, Salina; Juergens, Rosalyn A.; Topalian, Suzanne L.; Rudin, Charles M.; Brock, Malcolm V.; Pardoll, Drew; Baylin, Stephen B.

2013-01-01

Innovative therapies are needed for advanced Non-Small Cell Lung Cancer (NSCLC). We have undertaken a genomics based, hypothesis driving, approach to query an emerging potential that epigenetic therapy may sensitize to immune checkpoint therapy targeting PD-L1/PD-1 interaction. NSCLC cell lines were treated with the DNA hypomethylating agent azacytidine (AZA – Vidaza) and genes and pathways altered were mapped by genome-wide expression and DNA methylation analyses. AZA-induced pathways were analyzed in The Cancer Genome Atlas (TCGA) project by mapping the derived gene signatures in hundreds of lung adeno (LUAD) and squamous cell carcinoma (LUSC) samples. AZA up-regulates genes and pathways related to both innate and adaptive immunity and genes related to immune evasion in a several NSCLC lines. DNA hypermethylation and low expression of IRF7, an interferon transcription factor, tracks with this signature particularly in LUSC. In concert with these events, AZA up-regulates PD-L1 transcripts and protein, a key ligand-mediator of immune tolerance. Analysis of TCGA samples demonstrates that a significant proportion of primary NSCLC have low expression of AZA-induced immune genes, including PD-L1. We hypothesize that epigenetic therapy combined with blockade of immune checkpoints – in particular the PD-1/PD-L1 pathway – may augment response of NSCLC by shifting the balance between immune activation and immune inhibition, particularly in a subset of NSCLC with low expression of these pathways. Our studies define a biomarker strategy for response in a recently initiated trial to examine the potential of epigenetic therapy to sensitize patients with NSCLC to PD-1 immune checkpoint blockade. PMID:24162015

Immunotherapy Targets in Pediatric Cancer

PubMed Central

Orentas, Rimas J.; Lee, Daniel W.; Mackall, Crystal

2011-01-01

Immunotherapy for cancer has shown increasing success and there is ample evidence to expect that progress gleaned in immune targeting of adult cancers can be translated to pediatric oncology. This manuscript reviews principles that guide selection of targets for immunotherapy of cancer, emphasizing the similarities and distinctions between oncogene-inhibition targets and immune targets. It follows with a detailed review of molecules expressed by pediatric tumors that are already under study as immune targets or are good candidates for future studies of immune targeting. Distinctions are made between cell surface antigens that can be targeted in an MHC independent manner using antibodies, antibody derivatives, or chimeric antigen receptors versus intracellular antigens which must be targeted with MHC restricted T cell therapies. Among the most advanced immune targets for childhood cancer are CD19 and CD22 on hematologic malignancies, GD2 on solid tumors, and NY-ESO-1 expressed by a majority of synovial sarcomas, but several other molecules reviewed here also have properties which suggest that they too could serve as effective targets for immunotherapy of childhood cancer. PMID:22645714

A basic mathematical model of the immune response

NASA Astrophysics Data System (ADS)

Mayer, H.; Zaenker, K. S.; an der Heiden, U.

1995-03-01

Interaction of the immune system with a target population of, e.g., bacteria, viruses, antigens, or tumor cells must be considered as a dynamic process. We describe this process by a system of two ordinary differential equations. Although the model is strongly idealized it demonstrates how the combination of a few proposed nonlinear interaction rules between the immune system and its targets are able to generate a considerable variety of different kinds of immune responses, many of which are observed both experimentally and clinically. In particular, solutions of the model equations correspond to states described by immunologists as ``virgin state,'' ``immune state'' and ``state of tolerance.'' The model successfully replicates the so-called primary and secondary response. Moreover, it predicts the existence of a threshold level for the amount of pathogen germs or of transplanted tumor cells below which the host is able to eliminate the infectious organism or to reject the tumor graft. We also find a long time coexistence of targets and immune competent cells including damped and undamped oscillations of both. Plausibly the model explains that if the number of transformed cells or pathogens exeeds definable values (poor antigenicity, high reproduction rate) the immune system fails to keep the disease under control. On the other hand, the model predicts apparently paradoxical situations including an increased chance of target survival despite enhanced immune activity or therapeutically achieved target reduction. A further obviously paradoxical behavior consists of a positive effect for the patient up to a complete cure by adding an additional target challenge where the benefit of the additional targets depends strongly on the time point and on their amount. Under periodically pulsed stimulation the model may show a chaotic time behavior of both target growth and immune response.

Mast cell: an emerging partner in immune interaction.

PubMed

Gri, Giorgia; Frossi, Barbara; D'Inca, Federica; Danelli, Luca; Betto, Elena; Mion, Francesca; Sibilano, Riccardo; Pucillo, Carlo

2012-01-01

Mast cells (MCs) are currently recognized as effector cells in many settings of the immune response, including host defense, immune regulation, allergy, chronic inflammation, and autoimmune diseases. MC pleiotropic functions reflect their ability to secrete a wide spectrum of preformed or newly synthesized biologically active products with pro-inflammatory, anti-inflammatory and/or immunosuppressive properties, in response to multiple signals. Moreover, the modulation of MC effector phenotypes relies on the interaction of a wide variety of membrane molecules involved in cell-cell or cell-extracellular-matrix interaction. The delivery of co-stimulatory signals allows MC to specifically communicate with immune cells belonging to both innate and acquired immunity, as well as with non-immune tissue-specific cell types. This article reviews and discusses the evidence that MC membrane-expressed molecules play a central role in regulating MC priming and activation and in the modulation of innate and adaptive immune response not only against host injury, but also in peripheral tolerance and tumor-surveillance or -escape. The complex expression of MC surface molecules may be regarded as a measure of connectivity, with altered patterns of cell-cell interaction representing functionally distinct MC states. We will focalize our attention on roles and functions of recently discovered molecules involved in the cross-talk of MCs with other immune partners.

Single-cell technologies to study the immune system.

PubMed

Proserpio, Valentina; Mahata, Bidesh

2016-02-01

The immune system is composed of a variety of cells that act in a coordinated fashion to protect the organism against a multitude of different pathogens. The great variability of existing pathogens corresponds to a similar high heterogeneity of the immune cells. The study of individual immune cells, the fundamental unit of immunity, has recently transformed from a qualitative microscopic imaging to a nearly complete quantitative transcriptomic analysis. This shift has been driven by the rapid development of multiple single-cell technologies. These new advances are expected to boost the detection of less frequent cell types and transient or intermediate cell states. They will highlight the individuality of each single cell and greatly expand the resolution of current available classifications and differentiation trajectories. In this review we discuss the recent advancement and application of single-cell technologies, their limitations and future applications to study the immune system. © 2015 The Authors. Immunology Published by John Wiley & Sons Ltd.

GEC-targeted HO-1 expression reduces proteinuria in glomerular immune injury.

PubMed

Duann, Pu; Lianos, Elias A

2009-09-01

Induction of heme oxygenase (HO)-1 is a key defense mechanism against oxidative stress. Compared with tubules, glomeruli are refractory to HO-1 upregulation in response to injury. This can be a disadvantage as it may be associated with insufficient production of cytoprotective heme-degradation metabolites. We, therefore, explored whether 1) targeted HO-1 expression can be achieved in glomeruli without altering their physiological integrity and 2) this expression reduces proteinuria in immune injury induced by an anti-glomerular basement membrane (GBM) antibody (Ab). We employed a 4.125-kb fragment of a mouse nephrin promoter downstream to which a FLAG-tagged hHO-1 cDNA sequence was inserted and subsequently generated transgenic mice from the FVB/N parental strain. There was a 16-fold higher transgene expression in the kidney than nonspecific background (liver) while the transprotein immunolocalized in glomerular epithelial cells (GEC). There was no change in urinary protein excretion, indicating that GEC-targeted HO-1 expression had no effect on glomerular protein permeability. Urinary protein excretion in transgenic mice with anti-GBM Ab injury (days 3 and 6) was significantly lower compared with wild-type controls. There was no significant change in renal expression levels of profibrotic (TGF-beta1) or anti-inflammatory (IL-10) cytokines in transgenic mice with anti-GBM Ab injury. These observations indicate that GEC-targeted HO-1 expression does not alter glomerular physiological integrity and reduces proteinuria in glomerular immune injury.

GEC-targeted HO-1 expression reduces proteinuria in glomerular immune injury

PubMed Central

Duann, Pu; Lianos, Elias A.

2009-01-01

Induction of heme oxygenase (HO)-1 is a key defense mechanism against oxidative stress. Compared with tubules, glomeruli are refractory to HO-1 upregulation in response to injury. This can be a disadvantage as it may be associated with insufficient production of cytoprotective heme-degradation metabolites. We, therefore, explored whether 1) targeted HO-1 expression can be achieved in glomeruli without altering their physiological integrity and 2) this expression reduces proteinuria in immune injury induced by an anti-glomerular basement membrane (GBM) antibody (Ab). We employed a 4.125-kb fragment of a mouse nephrin promoter downstream to which a FLAG-tagged hHO-1 cDNA sequence was inserted and subsequently generated transgenic mice from the FVB/N parental strain. There was a 16-fold higher transgene expression in the kidney than nonspecific background (liver) while the transprotein immunolocalized in glomerular epithelial cells (GEC). There was no change in urinary protein excretion, indicating that GEC-targeted HO-1 expression had no effect on glomerular protein permeability. Urinary protein excretion in transgenic mice with anti-GBM Ab injury (days 3 and 6) was significantly lower compared with wild-type controls. There was no significant change in renal expression levels of profibrotic (TGF-β1) or anti-inflammatory (IL-10) cytokines in transgenic mice with anti-GBM Ab injury. These observations indicate that GEC-targeted HO-1 expression does not alter glomerular physiological integrity and reduces proteinuria in glomerular immune injury. PMID:19587144

Chimeric Antigen Receptor-Engineered NK-92 Cells: An Off-the-Shelf Cellular Therapeutic for Targeted Elimination of Cancer Cells and Induction of Protective Antitumor Immunity.

PubMed

Zhang, Congcong; Oberoi, Pranav; Oelsner, Sarah; Waldmann, Anja; Lindner, Aline; Tonn, Torsten; Wels, Winfried S

2017-01-01

Significant progress has been made in recent years toward realizing the potential of natural killer (NK) cells for cancer immunotherapy. NK cells can respond rapidly to transformed and stressed cells and have the intrinsic potential to extravasate and reach their targets in almost all body tissues. In addition to donor-derived primary NK cells, also the established NK cell line NK-92 is being developed for adoptive immunotherapy, and general safety of infusion of irradiated NK-92 cells has been established in phase I clinical trials with clinical responses observed in some of the cancer patients treated. To enhance their therapeutic utility, NK-92 cells have been modified to express chimeric antigen receptors (CARs) composed of a tumor-specific single chain fragment variable antibody fragment fused via hinge and transmembrane regions to intracellular signaling moieties such as CD3ζ or composite signaling domains containing a costimulatory protein together with CD3ζ. CAR-mediated activation of NK cells then bypasses inhibitory signals and overcomes NK resistance of tumor cells. In contrast to primary NK cells, CAR-engineered NK-92 cell lines suitable for clinical development can be established from molecularly and functionally well-characterized single cell clones following good manufacturing practice-compliant procedures. In preclinical in vitro and in vivo models, potent antitumor activity of NK-92 variants targeted to differentiation antigens expressed by hematologic malignancies, and overexpressed or mutated self-antigens associated with solid tumors has been found, encouraging further development of CAR-engineered NK-92 cells. Importantly, in syngeneic mouse tumor models, induction of endogenous antitumor immunity after treatment with CAR-expressing NK-92 cells has been demonstrated, resulting in cures and long-lasting immunological memory protecting against tumor rechallenge at distant sites. Here, we summarize the current status and future prospects of CAR

Chimeric Antigen Receptor-Engineered NK-92 Cells: An Off-the-Shelf Cellular Therapeutic for Targeted Elimination of Cancer Cells and Induction of Protective Antitumor Immunity

PubMed Central

Zhang, Congcong; Oberoi, Pranav; Oelsner, Sarah; Waldmann, Anja; Lindner, Aline; Tonn, Torsten; Wels, Winfried S.

2017-01-01

Significant progress has been made in recent years toward realizing the potential of natural killer (NK) cells for cancer immunotherapy. NK cells can respond rapidly to transformed and stressed cells and have the intrinsic potential to extravasate and reach their targets in almost all body tissues. In addition to donor-derived primary NK cells, also the established NK cell line NK-92 is being developed for adoptive immunotherapy, and general safety of infusion of irradiated NK-92 cells has been established in phase I clinical trials with clinical responses observed in some of the cancer patients treated. To enhance their therapeutic utility, NK-92 cells have been modified to express chimeric antigen receptors (CARs) composed of a tumor-specific single chain fragment variable antibody fragment fused via hinge and transmembrane regions to intracellular signaling moieties such as CD3ζ or composite signaling domains containing a costimulatory protein together with CD3ζ. CAR-mediated activation of NK cells then bypasses inhibitory signals and overcomes NK resistance of tumor cells. In contrast to primary NK cells, CAR-engineered NK-92 cell lines suitable for clinical development can be established from molecularly and functionally well-characterized single cell clones following good manufacturing practice-compliant procedures. In preclinical in vitro and in vivo models, potent antitumor activity of NK-92 variants targeted to differentiation antigens expressed by hematologic malignancies, and overexpressed or mutated self-antigens associated with solid tumors has been found, encouraging further development of CAR-engineered NK-92 cells. Importantly, in syngeneic mouse tumor models, induction of endogenous antitumor immunity after treatment with CAR-expressing NK-92 cells has been demonstrated, resulting in cures and long-lasting immunological memory protecting against tumor rechallenge at distant sites. Here, we summarize the current status and future prospects of CAR

Effects of Food Additives on Immune Cells As Contributors to Body Weight Gain and Immune-Mediated Metabolic Dysregulation

PubMed Central

Paula Neto, Heitor A.; Ausina, Priscila; Gomez, Lilian S.; Leandro, João G. B.; Zancan, Patricia; Sola-Penna, Mauro

2017-01-01

Food additives are compounds used in order to improve food palatability, texture, and shelf life. Despite a significant effort to assure safety of use, toxicological analysis of these substances, generally, rely on their direct toxicity to target organs (liver and kidney) or their genotoxic effects. Much less attention is paid to the effects of these compounds on cells of the immune system. This is of relevance given that metabolic dysregulation and obesity have a strong immune-mediated component. Obese individuals present a state of chronic low-grade inflammation that contributes to the establishment of insulin resistance and other metabolic abnormalities known as the metabolic syndrome. Obesity and metabolic syndrome are currently recognized as worldwide epidemics that pose a profound socioeconomic impact and represent a concern to public health. Cells of the immune system contribute to both the maintenance of “lean homeostasis” and the metabolic dysregulation observed in obese individuals. Although much attention has been drawn in the past decades to obesity and metabolic syndrome as a result of ingesting highly processed food containing large amounts of fat and simple sugars, mounting evidence suggest that food additives may also be important contributors to metabolic derangement. Herein, we review pieces of evidence from the literature showing that food additives have relevant effects on cells of the immune system that could contribute to immune-mediated metabolic dysregulation. Considering their potential to predispose individuals to develop obesity and metabolic syndrome, their use should be taken with caution or maybe revisited. PMID:29163542

RNA sequencing analysis of human podocytes reveals glucocorticoid regulated gene networks targeting non-immune pathways

PubMed Central

Jiang, Lulu; Hindmarch, Charles C. T.; Rogers, Mark; Campbell, Colin; Waterfall, Christy; Coghill, Jane; Mathieson, Peter W.; Welsh, Gavin I.

2016-01-01

Glucocorticoids are steroids that reduce inflammation and are used as immunosuppressive drugs for many diseases. They are also the mainstay for the treatment of minimal change nephropathy (MCN), which is characterised by an absence of inflammation. Their mechanisms of action remain elusive. Evidence suggests that immunomodulatory drugs can directly act on glomerular epithelial cells or ‘podocytes’, the cell type which is the main target of injury in MCN. To understand the nature of glucocorticoid effects on non-immune cell functions, we generated RNA sequencing data from human podocyte cell lines and identified the genes that are significantly regulated in dexamethasone-treated podocytes compared to vehicle-treated cells. The upregulated genes are of functional relevance to cytoskeleton-related processes, whereas the downregulated genes mostly encode pro-inflammatory cytokines and growth factors. We observed a tendency for dexamethasone-upregulated genes to be downregulated in MCN patients. Integrative analysis revealed gene networks composed of critical signaling pathways that are likely targeted by dexamethasone in podocytes. PMID:27774996

Targeted delivery of TLR ligands to human and mouse dendritic cells strongly enhances adjuvanticity.

PubMed

Tacken, Paul J; Zeelenberg, Ingrid S; Cruz, Luis J; van Hout-Kuijer, Maaike A; van de Glind, Gerline; Fokkink, Remco G; Lambeck, Annechien J A; Figdor, Carl G

2011-12-22

Effective vaccines consist of 2 components: immunodominant antigens and effective adjuvants. Whereas it has been demonstrated that targeted delivery of antigens to dendritic cells (DCs) improves vaccine efficacy, we report here that co-targeting of TLR ligands (TLRLs) to DCs strongly enhances adjuvanticity and immunity. We encapsulated ligands for intracellular TLRs within biodegradable nanoparticles coated with Abs recognizing DC-specific receptors. Targeted delivery of TLRLs to human DCs enhanced the maturation and production of immune stimulatory cytokines and the Ag-specific activation of naive CD8(+) T cells. In vivo studies demonstrated that nanoparticles carrying Ag induced cytotoxic T-lymphocyte responses at 100-fold lower adjuvant dose when TLRLs were co-encapsulated instead of administered in soluble form. Moreover, the efficacy of these targeted TLRLs reduced the serum cytokine storm and related toxicity that is associated with administration of soluble TLRLs. We conclude that the targeted delivery of adjuvants may improve the efficacy and safety of DC-based vaccines.

Cell cycle-tailored targeting of metastatic melanoma: Challenges and opportunities.

PubMed

Haass, Nikolas K; Gabrielli, Brian

2017-07-01

The advent of targeted therapies of metastatic melanoma, such as MAPK pathway inhibitors and immune checkpoint antagonists, has turned dermato-oncology from the "bad guy" to the "poster child" in oncology. Current targeted therapies are effective, although here is a clear need to develop combination therapies to delay the onset of resistance. Many antimelanoma drugs impact on the cell cycle but are also dependent on certain cell cycle phases resulting in cell cycle phase-specific drug insensitivity. Here, we raise the question: Have combination trials been abandoned prematurely as ineffective possibly only because drug scheduling was not optimized? Firstly, if both drugs of a combination hit targets in the same melanoma cell, cell cycle-mediated drug insensitivity should be taken into account when planning combination therapies, timing of dosing schedules and choice of drug therapies in solid tumors. Secondly, if the combination is designed to target different tumor cell subpopulations of a heterogeneous tumor, one drug effective in a particular subpopulation should not negatively impact on the other drug targeting another subpopulation. In addition to the role of cell cycle stage and progression on standard chemotherapeutics and targeted drugs, we discuss the utilization of cell cycle checkpoint control defects to enhance chemotherapeutic responses or as targets themselves. We propose that cell cycle-tailored targeting of metastatic melanoma could further improve therapy outcomes and that our real-time cell cycle imaging 3D melanoma spheroid model could be utilized as a tool to measure and design drug scheduling approaches. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In vitro senescence of immune cells.

PubMed

Effros, Rita B; Dagarag, Mirabelle; Valenzuela, Hector F

2003-01-01

Immune cells are eminently suitable model systems in which to address the possible role of replicative senescence during in vivo aging. Since there are more than 10(8) unique antigen specificities present within the total T lymphocyte population of each individual, the immune response to any single antigen requires massive clonal expansion of the small proportion of T cells whose receptors recognize that antigen. The Hayflick Limit may, therefore, constitute a barrier to effective immune function, at least for those T cells that encounter their specific antigen more than once over the life course. Application of the fibroblast replicative senescence model to the so-called cytotoxic or CD8 T cell, the class of T cells that controls viral infection and cancer, has revealed certain features in common with other cell types as well as several characteristics that are unique to T cells. One senescence-associated change that is T cell-specific is the complete loss of expression of the activation signaling surface molecule, CD28, an alteration that enabled the documentation of high proportions of senescent T cells in vivo. The T cell model has also provided the unique opportunity to analyze telomere dynamics in a cell type that has the ability to upregulate telomerase yet nevertheless undergoes senescence. The intimate involvement of the immune system in the control of pathogens and cancer as well as in modulation of bone homeostasis suggests that more extensive analysis of the full range of characteristics of senescent T cells may help elucidate a broad spectrum of age-associated physiological changes.

T cells targeting a neuronal paraneoplastic antigen mediate tumor rejection and trigger CNS autoimmunity with humoral activation.

PubMed

Blachère, Nathalie E; Orange, Dana E; Santomasso, Bianca D; Doerner, Jessica; Foo, Patricia K; Herre, Margaret; Fak, John; Monette, Sébastien; Gantman, Emily C; Frank, Mayu O; Darnell, Robert B

2014-11-01

Paraneoplastic neurologic diseases (PND) involving immune responses directed toward intracellular antigens are poorly understood. Here, we examine immunity to the PND antigen Nova2, which is expressed exclusively in central nervous system (CNS) neurons. We hypothesized that ectopic expression of neuronal antigen in the periphery could incite PND. In our C57BL/6 mouse model, CNS antigen expression limits antigen-specific CD4+ and CD8+ T-cell expansion. Chimera experiments demonstrate that this tolerance is mediated by antigen expression in nonhematopoietic cells. CNS antigen expression does not limit tumor rejection by adoptively transferred transgenic T cells but does limit the generation of a memory population that can be expanded upon secondary challenge in vivo. Despite mediating cancer rejection, adoptively transferred transgenic T cells do not lead to paraneoplastic neuronal targeting. Preliminary experiments suggest an additional requirement for humoral activation to induce CNS autoimmunity. This work provides evidence that the requirements for cancer immunity and neuronal autoimmunity are uncoupled. Since humoral immunity was not required for tumor rejection, B-cell targeting therapy, such as rituximab, may be a rational treatment option for PND that does not hamper tumor immunity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Disruption of IL-21 Signaling Affects T Cell-B Cell Interactions and Abrogates Protective Humoral Immunity to Malaria

PubMed Central

Pérez-Mazliah, Damián; Ng, Dorothy Hui Lin; Freitas do Rosário, Ana Paula; McLaughlin, Sarah; Mastelic-Gavillet, Béatris; Sodenkamp, Jan; Kushinga, Garikai; Langhorne, Jean

2015-01-01

Interleukin-21 signaling is important for germinal center B-cell responses, isotype switching and generation of memory B cells. However, a role for IL-21 in antibody-mediated protection against pathogens has not been demonstrated. Here we show that IL-21 is produced by T follicular helper cells and co-expressed with IFN-γ during an erythrocytic-stage malaria infection of Plasmodium chabaudi in mice. Mice deficient either in IL-21 or the IL-21 receptor fail to resolve the chronic phase of P. chabaudi infection and P. yoelii infection resulting in sustained high parasitemias, and are not immune to re-infection. This is associated with abrogated P. chabaudi-specific IgG responses, including memory B cells. Mixed bone marrow chimeric mice, with T cells carrying a targeted disruption of the Il21 gene, or B cells with a targeted disruption of the Il21r gene, demonstrate that IL-21 from T cells signaling through the IL-21 receptor on B cells is necessary to control chronic P. chabaudi infection. Our data uncover a mechanism by which CD4+ T cells and B cells control parasitemia during chronic erythrocytic-stage malaria through a single gene, Il21, and demonstrate the importance of this cytokine in the control of pathogens by humoral immune responses. These data are highly pertinent for designing malaria vaccines requiring long-lasting protective B-cell responses. PMID:25763578

Immune drug discovery from venoms.

PubMed

Jimenez, Rocio; Ikonomopoulou, Maria P; Lopez, J Alejandro; Miles, John J

2018-01-01

This review catalogues recent advances in knowledge on venoms as standalone therapeutic agents or as blueprints for drug design, with an emphasis on venom-derived compounds that affects the immune system. We discuss venoms and venom-derived compounds that affect total immune cell numbers, immune cell proliferation, immune cell migration, immune cell phenotype and cytokine secretion. Identifying novel compounds that 'tune' the system, up-regulating the immune response during infectious disease and cancer and down-regulating the immune response during autoimmunity, will greatly expand the tool kit of human immunotherapeutics. Targeting these pathways may also open therapeutic options that alleviate symptoms of envenomation. Finally, combining recent advances in venomics with progress in low cost, high-throughput screening platforms will no doubt yield hundreds of prototype immune modulating compounds in the coming years. Copyright © 2017 Elsevier Ltd. All rights reserved.

Targeting LAG-3 and PD-1 to Enhance T Cell Activation by Antigen-Presenting Cells

PubMed Central

Lichtenegger, Felix S.; Rothe, Maurine; Schnorfeil, Frauke M.; Deiser, Katrin; Krupka, Christina; Augsberger, Christian; Schlüter, Miriam; Neitz, Julia; Subklewe, Marion

2018-01-01

Immune checkpoint inhibition has been shown to successfully reactivate endogenous T cell responses directed against tumor-associated antigens, resulting in significantly prolonged overall survival in patients with various tumor entities. For malignancies with low endogenous immune responses, this approach has not shown a clear clinical benefit so far. Therapeutic vaccination, particularly dendritic cell (DC) vaccination, is a strategy to induce T cell responses. Interaction of DCs and T cells is dependent on receptor–ligand interactions of various immune checkpoints. In this study, we analyzed the influence of blocking antibodies targeting programmed cell death protein 1 (PD-1), HVEM, CD244, TIM-3, and lymphocyte activation gene 3 (LAG-3) on the proliferation and cytokine secretion of T cells after stimulation with autologous TLR-matured DCs. In this context, we found that LAG-3 blockade resulted in superior T cell activation compared to inhibition of other pathways, including PD-1/PD-L1. This result was consistent across different methods to measure T cell stimulation (proliferation, IFN-γ secretion), various stimulatory antigens (viral and bacterial peptide pool, specific viral antigen, specific tumor antigen), and seen for both CD4+ and CD8+ T cells. Only under conditions with a weak antigenic stimulus, particularly when combining antigen presentation by peripheral blood mononuclear cells with low concentrations of peptides, we observed the highest T cell stimulation with dual blockade of LAG-3 and PD-1 blockade. We conclude that priming of novel immune responses can be strongly enhanced by blockade of LAG-3 or dual blockade of LAG-3 and PD-1, depending on the strength of the antigenic stimulus. PMID:29535740

Targeting LAG-3 and PD-1 to Enhance T Cell Activation by Antigen-Presenting Cells.

PubMed

Lichtenegger, Felix S; Rothe, Maurine; Schnorfeil, Frauke M; Deiser, Katrin; Krupka, Christina; Augsberger, Christian; Schlüter, Miriam; Neitz, Julia; Subklewe, Marion

2018-01-01

Immune checkpoint inhibition has been shown to successfully reactivate endogenous T cell responses directed against tumor-associated antigens, resulting in significantly prolonged overall survival in patients with various tumor entities. For malignancies with low endogenous immune responses, this approach has not shown a clear clinical benefit so far. Therapeutic vaccination, particularly dendritic cell (DC) vaccination, is a strategy to induce T cell responses. Interaction of DCs and T cells is dependent on receptor-ligand interactions of various immune checkpoints. In this study, we analyzed the influence of blocking antibodies targeting programmed cell death protein 1 (PD-1), HVEM, CD244, TIM-3, and lymphocyte activation gene 3 (LAG-3) on the proliferation and cytokine secretion of T cells after stimulation with autologous TLR-matured DCs. In this context, we found that LAG-3 blockade resulted in superior T cell activation compared to inhibition of other pathways, including PD-1/PD-L1. This result was consistent across different methods to measure T cell stimulation (proliferation, IFN-γ secretion), various stimulatory antigens (viral and bacterial peptide pool, specific viral antigen, specific tumor antigen), and seen for both CD4 + and CD8 + T cells. Only under conditions with a weak antigenic stimulus, particularly when combining antigen presentation by peripheral blood mononuclear cells with low concentrations of peptides, we observed the highest T cell stimulation with dual blockade of LAG-3 and PD-1 blockade. We conclude that priming of novel immune responses can be strongly enhanced by blockade of LAG-3 or dual blockade of LAG-3 and PD-1, depending on the strength of the antigenic stimulus.

Expression and regulation of proton-coupled oligopeptide transporters in colonic tissue and immune cells of mice.

PubMed

Wang, Yuqing; Hu, Yongjun; Li, Ping; Weng, Yayun; Kamada, Nobuhiko; Jiang, Huidi; Smith, David E

2018-02-01

A number of studies have implicated proton-coupled oligopeptide transporters (POTs) in the initiation and/or progression of inflammatory bowel disease and immune cell signaling. With this in mind, the aim of this study was to delineate the expression of POTs in mouse colonic tissues and immune cells, and characterize the potential role of these transporters in nucleotide-binding oligomerization domain (NOD) signaling. Using a dextran sodium sulfate (DSS)-induced colitis mouse model, we found that DSS down regulated Pht1 gene expression and up regulated Pht2 gene expression in colonic tissue and immune cells. In contrast, PEPT1 protein was absent from the colonic tissue and immune cells of normal and DSS-treated mice. NOD ligands, muramyl dipeptide (MDP) and l-Ala-γ-d-Glu-meso-diaminopimelic acid (tri-DAP), were shown to be substrates of PHT2 in MDCK-hPHT2 19,20AA cells. Subsequent studies revealed that the immune response of lamina propia mononuclear cells may be regulated by PHT1 and PHT2, and that PHT2 facilitated the NOD-dependent immune response in RAW264.7 macrophages. These results clarified the expression of POTs in mouse colonic segments, cells and subtypes, and the role of increased Pht2 expression during chemically-induced colitis in facilitating NOD-dependent immune response. The findings further suggest that intestinal PHT2 may serve as a therapeutic target for IBD therapy. Copyright © 2018 Elsevier Inc. All rights reserved.

An improved plaque assay for mouse myeloma (MOPC 315) cells for use in studies of humoral and cell-mediated immunity.

PubMed

Levin, D; Jonak, J; Harris, T N

1977-01-01

Dinitrophenyl-bovine albumin was coupled at room temperature to sheep red blood cells in a procedure which minimized spontaneous lysis and allowed the preparation of large batches and their use for at least 3 weeks. The modified erythrocytes were used as a substrate for detecting local hemolytic plaques in agar by myeloma MOPC 315 cells, which secrete a paraprotein IgA with high affinity for dinitrophenyl ligand. Conditions maximizing the number of plaques formed by a given number of tumor cells were found to include coupling the erythrocytes at 1 mg/ml dinitrophenyl-bovine albumin with a molar ratio of about 50, and incubation with an amino-to-carboxy cross-linking agent, 1-ethyl-3(3 dimethyl aminopropyl) carbodiimide, at 2 mg/ml for 50 min. The method thus developed was employed to measure cellular and antibody-dependent immune reactions against the MOPC 315 cells. The experimental results show comparisons of the plaque technique with other measurements of tumor cell injury. The nature of the assay, which requires only 500 cells per plating, and which tests the synthetic capacity of single cells, suggests its use in experiments which limit the number of target cells, and in immune reactions causing injury, but not necessarily lysis, of the target cells.

Extracellular cell stress (heat shock) proteins-immune responses and disease: an overview.

PubMed

Pockley, A Graham; Henderson, Brian

2018-01-19

Extracellular cell stress proteins are highly conserved phylogenetically and have been shown to act as powerful signalling agonists and receptors for selected ligands in several different settings. They also act as immunostimulatory 'danger signals' for the innate and adaptive immune systems. Other studies have shown that cell stress proteins and the induction of immune reactivity to self-cell stress proteins can attenuate disease processes. Some proteins (e.g. Hsp60, Hsp70, gp96) exhibit both inflammatory and anti-inflammatory properties, depending on the context in which they encounter responding immune cells. The burgeoning literature reporting the presence of stress proteins in a range of biological fluids in healthy individuals/non-diseased settings, the association of extracellular stress protein levels with a plethora of clinical and pathological conditions and the selective expression of a membrane form of Hsp70 on cancer cells now supports the concept that extracellular cell stress proteins are involved in maintaining/regulating organismal homeostasis and in disease processes and phenotype. Cell stress proteins, therefore, form a biologically complex extracellular cell stress protein network having diverse biological, homeostatic and immunomodulatory properties, the understanding of which offers exciting opportunities for delivering novel approaches to predict, identify, diagnose, manage and treat disease.This article is part of the theme issue 'Heat shock proteins as modulators and therapeutic targets of chronic disease: an integrated perspective'. © 2017 The Author(s).

Targeting the permeability barrier and peptidoglycan recycling pathways to disarm Pseudomonas aeruginosa against the innate immune system

PubMed Central

Moya, Bartolomé; Munar-Bestard, Marta; Zamorano, Laura; Cabot, Gabriel; Blázquez, Jesús; Ayala, Juan A.; Oliver, Antonio

2017-01-01

Antimicrobial resistance is a continuously increasing threat that severely compromises our antibiotic arsenal and causes thousands of deaths due to hospital-acquired infections by pathogens such as Pseudomonas aeruginosa, situation further aggravated by the limited development of new antibiotics. Thus, alternative strategies such as those targeting bacterial resistance mechanisms, virulence or potentiating the activity of our immune system resources are urgently needed. We have recently shown that mutations simultaneously causing the peptidoglycan recycling blockage and the β-lactamase AmpC overexpression impair the virulence of P.aeruginosa. These findings suggested that peptidoglycan metabolism might be a good target not only for fighting antibiotic resistance, but also for the attenuation of virulence and/or potentiation of our innate immune weapons. Here we analyzed the activity of the innate immune elements peptidoglycan recognition proteins (PGRPs) and lysozyme against P. aeruginosa. We show that while lysozyme and PGRPs have a very modest basal effect over P. aeruginosa, their bactericidal activity is dramatically increased in the presence of subinhibitory concentrations of the permeabilizing agent colistin. We also show that the P. aeruginosa lysozyme inhibitors seem to play a very residual protective role even in permeabilizing conditions. In contrast, we demonstrate that, once the permeability barrier is overpassed, the activity of lysozyme and PGRPs is dramatically enhanced when inhibiting key peptidoglycan recycling components (such as the 3 AmpDs, AmpG or NagZ), indicating a decisive protective role for cell-wall recycling and that direct peptidoglycan-binding supports, at least partially, the activity of these enzymes. Finally, we show that recycling blockade when occurring simultaneously with AmpC overexpression determines a further decrease in the resistance against PGRP2 and lysozyme, linked to quantitative changes in the cell-wall. Thus, our

The Role of NKT Cells in Tumor Immunity

PubMed Central

Terabe, Masaki; Berzofsky, Jay A.

2009-01-01

NKT cells are a relatively newly recognized member of the immune community, with profound effects on the rest of the immune system despite their small numbers. They are true T cells with a T cell receptor (TCR), but unlike conventional T cells that detect peptide antigens presented by conventional major histocompatibility (MHC) molecules, NKT cells recognize lipid antigens presented by CD1d, a non-classical MHC molecule. As members of both the innate and adaptive immune systems, they bridge the gap between these, and respond rapidly to set the tone for subsequent immune responses. They fill a unique niche in providing the immune system a cellular arm to recognize lipid antigens. They play both effector and regulatory roles in infectious and autoimmune diseases. Furthermore, subsets of NKT cells can play distinct and sometimes opposing roles. In cancer, type I NKT cells, defined by their invariant TCR using Vα14Jα18 in mice and Vα24Jα18 in humans, are mostly protective, by producing interferon-γ to activate NK and CD8+ T cells and by activating dendritic cells to make IL-12. In contrast, type II NKT cells, characterized by more diverse TCRs recognizing lipids presented by CD1d, primarily inhibit tumor immunity. Moreover, type I and type II NKT cells counter-regulate each other, forming a new immunoregulatory axis. Because NKT cells respond rapidly, the balance along this axis can greatly influence other immune responses that follow. Therefore, learning to manipulate the balance along the NKT regulatory axis may be critical to devising successful immunotherapies for cancer. PMID:19055947

Platelets subvert T cell immunity against cancer via GARP-TGFβ axis.

PubMed

Rachidi, Saleh; Metelli, Alessandra; Riesenberg, Brian; Wu, Bill X; Nelson, Michelle H; Wallace, Caroline; Paulos, Chrystal M; Rubinstein, Mark P; Garrett-Mayer, Elizabeth; Hennig, Mirko; Bearden, Daniel W; Yang, Yi; Liu, Bei; Li, Zihai

2017-05-05

Cancer-associated thrombocytosis has long been linked to poor clinical outcome, but the underlying mechanism is enigmatic. We hypothesized that platelets promote malignancy and resistance to therapy by dampening host immunity. We show that genetic targeting of platelets enhances adoptive T cell therapy of cancer. An unbiased biochemical and structural biology approach established transforming growth factor β (TGFβ) and lactate as major platelet-derived soluble factors to obliterate CD4 + and CD8 + T cell functions. Moreover, we found that platelets are the dominant source of functional TGFβ systemically as well as in the tumor microenvironment through constitutive expression of the TGFβ-docking receptor glycoprotein A repetitions predominant (GARP) rather than secretion of TGFβ per se. Platelet-specific deletion of the GARP-encoding gene Lrrc32 blunted TGFβ activity at the tumor site and potentiated protective immunity against both melanoma and colon cancer. Last, this study shows that T cell therapy of cancer can be substantially improved by concurrent treatment with readily available antiplatelet agents. We conclude that platelets constrain T cell immunity through a GARP-TGFβ axis and suggest a combination of immunotherapy and platelet inhibitors as a therapeutic strategy against cancer. Copyright © 2017, American Association for the Advancement of Science.

STING activation of tumor endothelial cells initiates spontaneous and therapeutic antitumor immunity.

PubMed

Demaria, Olivier; De Gassart, Aude; Coso, Sanja; Gestermann, Nicolas; Di Domizio, Jeremy; Flatz, Lukas; Gaide, Olivier; Michielin, Olivier; Hwu, Patrick; Petrova, Tatiana V; Martinon, Fabio; Modlin, Robert L; Speiser, Daniel E; Gilliet, Michel

2015-12-15

Spontaneous CD8 T-cell responses occur in growing tumors but are usually poorly effective. Understanding the molecular and cellular mechanisms that drive these responses is of major interest as they could be exploited to generate a more efficacious antitumor immunity. As such, stimulator of IFN genes (STING), an adaptor molecule involved in cytosolic DNA sensing, is required for the induction of antitumor CD8 T responses in mouse models of cancer. Here, we find that enforced activation of STING by intratumoral injection of cyclic dinucleotide GMP-AMP (cGAMP), potently enhanced antitumor CD8 T responses leading to growth control of injected and contralateral tumors in mouse models of melanoma and colon cancer. The ability of cGAMP to trigger antitumor immunity was further enhanced by the blockade of both PD1 and CTLA4. The STING-dependent antitumor immunity, either induced spontaneously in growing tumors or induced by intratumoral cGAMP injection was dependent on type I IFNs produced in the tumor microenvironment. In response to cGAMP injection, both in the mouse melanoma model and an ex vivo model of cultured human melanoma explants, the principal source of type I IFN was not dendritic cells, but instead endothelial cells. Similarly, endothelial cells but not dendritic cells were found to be the principal source of spontaneously induced type I IFNs in growing tumors. These data identify an unexpected role of the tumor vasculature in the initiation of CD8 T-cell antitumor immunity and demonstrate that tumor endothelial cells can be targeted for immunotherapy of melanoma.

Should cell-free DNA testing be used to target antenatal rhesus immune globulin administration?

PubMed

Ma, Kimberly K; Rodriguez, Maria I; Cheng, Yvonne W; Norton, Mary E; Caughey, Aaron B

2016-01-01

To compare the rates of alloimmunization with the use of cell-free DNA (cfDNA) screening to target antenatal rhesus immune globulin (RhIG) prenatally, versus routine administration of RhIG in rhesus D (RhD)-negative pregnant women in a theoretic cohort using a decision-analytic model. A decision-analytic model compared cfDNA testing to routine antenatal RhIG administration. The primary outcome was maternal sensitization to RhD antigen. Sensitivity and specificity of cfDNA testing were assumed to be 99.8% and 95.3%, respectively. Univariate and bivariate sensitivity analyses, Monte Carlo simulation, and threshold analyses were performed. In a cohort of 10,000 RhD-negative women, 22.6 sensitizations would occur with utilization of cfDNA, while 20 sensitizations would occur with routine RhIG. Only when the sensitivity of the cfDNA test reached 100%, the rate of sensitization was equal for both cfDNA and RhIG. Otherwise, routine RhIG minimized the rate of sensitization, especially given RhIG is readily available in the United States. Adoption of cfDNA testing would result in a 13.0% increase in sensitization among RhD-negative women in a theoretical cohort taking into account the ethnic diversity of the United States' population.

Platelets and their interactions with other immune cells

PubMed Central

Lam, Fong W.; Vijayan, K. Vinod; Rumbaut, Rolando E.

2015-01-01

Platelets are anucleate blood cells, long known to be critically involved in hemostasis and thrombosis. In addition to their role in blood clots, increasing evidence reveals significant roles for platelets in inflammation and immunity. However, the notion that platelets represent immune cells is not broadly recognized in the field of Physiology. This manuscript reviews the role of platelets in inflammation and immune responses, and highlights their interactions with other immune cells, including examples of major functional consequences of these interactions. PMID:26140718

Immunization with apical membrane antigen 1 confers sterile infection-blocking immunity against Plasmodium sporozoite challenge in a rodent model.

PubMed

Schussek, Sophie; Trieu, Angela; Apte, Simon H; Sidney, John; Sette, Alessandro; Doolan, Denise L

2013-10-01

Apical membrane antigen 1 (AMA-1) is a leading blood-stage malaria vaccine candidate. Consistent with a key role in erythrocytic invasion, AMA-1-specific antibodies have been implicated in AMA-1-induced protective immunity. AMA-1 is also expressed in sporozoites and in mature liver schizonts where it may be a target of protective cell-mediated immunity. Here, we demonstrate for the first time that immunization with AMA-1 can induce sterile infection-blocking immunity against Plasmodium sporozoite challenge in 80% of immunized mice. Significantly higher levels of gamma interferon (IFN-γ)/interleukin-2 (IL-2)/tumor necrosis factor (TNF) multifunctional T cells were noted in immunized mice than in control mice. We also report the first identification of minimal CD8(+) and CD4(+) T cell epitopes on Plasmodium yoelii AMA-1. These data establish AMA-1 as a target of both preerythrocytic- and erythrocytic-stage protective immune responses and validate vaccine approaches designed to induce both cellular and humoral immunity.

Immune Privilege and Eye-Derived T-Regulatory Cells.

PubMed

Keino, Hiroshi; Horie, Shintaro; Sugita, Sunao

2018-01-01

Certain cellular components of the eye, such as neural retina, are unable to regenerate and replicate after destructive inflammation. Ocular immune privilege provides the eye with immune protection against intraocular inflammation in order to minimize the risk to vision integrity. The eye and immune system use strategies to maintain the ocular immune privilege by regulating the innate and adaptive immune response, which includes immunological ignorance, peripheral tolerance to eye-derived antigens, and intraocular immunosuppressive microenvironment. In this review, we summarize current knowledge regarding the molecular mechanism responsible for the development and maintenance of ocular immune privilege via regulatory T cells (Tregs), which are generated by the anterior chamber-associated immune deviation (ACAID), and ocular resident cells including corneal endothelial (CE) cells, ocular pigment epithelial (PE) cells, and aqueous humor. Furthermore, we examined the therapeutic potential of Tregs generated by RPE cells that express transforming growth factor beta (TGF- β ), cytotoxic T lymphocyte-associated antigen-2 alpha (CTLA-2 α ), and retinoic acid for autoimmune uveoretinitis and evaluated a new strategy using human RPE-induced Tregs for clinical application in inflammatory ocular disease. We believe that a better understanding of the ocular immune privilege associated with Tregs might offer a new approach with regard to therapeutic interventions for ocular autoimmunity.

Mast Cell: An Emerging Partner in Immune Interaction

PubMed Central

Gri, Giorgia; Frossi, Barbara; D’Inca, Federica; Danelli, Luca; Betto, Elena; Mion, Francesca; Sibilano, Riccardo; Pucillo, Carlo

2012-01-01

Mast cells (MCs) are currently recognized as effector cells in many settings of the immune response, including host defense, immune regulation, allergy, chronic inflammation, and autoimmune diseases. MC pleiotropic functions reflect their ability to secrete a wide spectrum of preformed or newly synthesized biologically active products with pro-inflammatory, anti-inflammatory and/or immunosuppressive properties, in response to multiple signals. Moreover, the modulation of MC effector phenotypes relies on the interaction of a wide variety of membrane molecules involved in cell–cell or cell-extracellular-matrix interaction. The delivery of co-stimulatory signals allows MC to specifically communicate with immune cells belonging to both innate and acquired immunity, as well as with non-immune tissue-specific cell types. This article reviews and discusses the evidence that MC membrane-expressed molecules play a central role in regulating MC priming and activation and in the modulation of innate and adaptive immune response not only against host injury, but also in peripheral tolerance and tumor-surveillance or -escape. The complex expression of MC surface molecules may be regarded as a measure of connectivity, with altered patterns of cell–cell interaction representing functionally distinct MC states. We will focalize our attention on roles and functions of recently discovered molecules involved in the cross-talk of MCs with other immune partners. PMID:22654879

Mesenchymal stromal cells (MSCs) and colorectal cancer: a troublesome twosome for the anti-tumour immune response?

PubMed Central

O'Malley, Grace; Heijltjes, Madelon; Houston, Aileen M.; Rani, Sweta; Ritter, Thomas; Egan, Laurence J.; Ryan, Aideen E.

2016-01-01

The tumour microenvironment (TME) is an important factor in determining the growth and metastasis of colorectal cancer, and can aid tumours by both establishing an immunosuppressive milieu, allowing the tumour avoid immune clearance, and by hampering the efficacy of various therapeutic regimens. The tumour microenvironment is composed of many cell types including tumour, stromal, endothelial and immune cell populations. It is widely accepted that cells present in the TME acquire distinct functional phenotypes that promote tumorigenesis. One such cell type is the mesenchymal stromal cell (MSC). Evidence suggests that MSCs exert effects in the colorectal tumour microenvironment including the promotion of angiogenesis, invasion and metastasis. MSCs immunomodulatory capacity may represent another largely unexplored central feature of MSCs tumour promoting capacity. There is considerable evidence to suggest that MSCs and their secreted factors can influence the innate and adaptive immune responses. MSC-immune cell interactions can skew the proliferation and functional activity of T-cells, dendritic cells, natural killer cells and macrophages, which could favour tumour growth and enable tumours to evade immune cell clearance. A better understanding of the interactions between the malignant cancer cell and stromal components of the TME is key to the development of more specific and efficacious therapies for colorectal cancer. Here, we review and explore MSC- mediated mechanisms of suppressing anti-tumour immune responses in the colon tumour microenvironment. Elucidation of the precise mechanism of immunomodulation exerted by tumour-educated MSCs is critical to inhibiting immunosuppression and immune evasion established by the TME, thus providing an opportunity for targeted and efficacious immunotherapy for colorectal cancer growth and metastasis. PMID:27542276

From Tumor Immunosuppression to Eradication: Targeting Homing and Activity of Immune Effector Cells to Tumors

PubMed Central

Draghiciu, Oana; Nijman, Hans W.; Daemen, Toos

2011-01-01

Unraveling the mechanisms used by the immune system to fight cancer development is one of the most ambitious undertakings in immunology. Detailed knowledge regarding the mechanisms of induction of tolerance and immunosuppression within the tumor microenvironment will contribute to the development of highly effective tumor eradication strategies. Research within the last few decades has shed more light on the matter. This paper aims to give an overview on the current knowledge of the main tolerance and immunosuppression mechanisms elicited within the tumor microenvironment, with the focus on development of effective immunotherapeutic strategies to improve homing and activity of immune effector cells to tumors. PMID:22190971

Computational tool for immunotoxic assessment of pyrethroids toward adaptive immune cell receptors.

PubMed

Kumar, Anoop; Behera, Padma Charan; Rangra, Naresh Kumar; Dey, Suddhasattya; Kant, Kamal

2018-01-01

Pyrethroids have prominently known for their insecticidal actions worldwide, but recent reports as anticancer and antiviral applications gained a lot of interest to further understand their safety and immunotoxicity. This encouraged us to carry out our present study to evaluate the interactions of pyrethroids toward adaptive immune cell receptors. Type 1 and Type 2 pyrethroids were tested on T (CD4 and CD8) and B (CD28 and CD45) immune cell receptors using Maestro 9.3 (Schrödinger, LLC, Cambridge, USA). In addition, top-ranked tested ligands were too explored for toxicity prediction in rodents using ProTOX tool. Pyrethroids (specifically type 2) such as fenvalerate (-5.534 kcal/mol: CD8), fluvalinate (-4.644 and - 4.431 kcal/mol: CD4 and CD45), and cypermethrin (-3.535 kcal/mol: CD28) have outcome in less energy or more affinity for B-cell and T-cell immune receptors which may later result in the immunosuppressive and hypersensitivity reactions. The current findings have uncovered that there is a further need to assess the Type 2 pyrethroids with wet laboratory experiments to understand the chemical nature of pyrethroid-induced immunotoxicity. Fenvalerate showed apex glide score toward CD8 immune receptor, while fluvalinate confirmed top-ranked binding with CD4 and CD45 immune proteinsIn addition, cypermethrin outcame in top glide score against CD28 immune receptorTop dock hits (Type 2) pyrethroids have shown probable toxicity targets toward AOFA: Amine oxidase (flavin-containing) A and PGH1: Prostaglandin G/H synthase 1, respectively. Abbreviations used: PDB: Protein Data Bank; AOFA: Amine oxidase (flavin-containing) A; PGH 1: Prostaglandin G/H synthase 1.

Intradermal injection of an anti-Langerin-HIVGag fusion vaccine targets epidermal Langerhans cells in nonhuman primates and can be tracked in vivo.

PubMed

Salabert, Nina; Todorova, Biliana; Martinon, Frédéric; Boisgard, Raphaël; Zurawski, Gerard; Zurawski, Sandra; Dereuddre-Bosquet, Nathalie; Cosma, Antonio; Kortulewski, Thierry; Banchereau, Jacques; Levy, Yves; Le Grand, Roger; Chapon, Catherine

2016-03-01

The development of new immunization strategies requires a better understanding of early molecular and cellular events occurring at the site of injection. The skin is particularly rich in immune cells and represents an attractive site for vaccine administration. Here, we specifically targeted vaccine antigens to epidermal Langerhans cells (LCs) using a fusion protein composed of HIV antigens and a monoclonal antibody targeting Langerin. We developed a fluorescence imaging approach to visualize, in vivo, the vaccine-targeted cells. Studies were performed in nonhuman primates (NHPs) because of their relevance as a model to assess human vaccines. We directly demonstrated that in NHPs, intradermally injected anti-Langerin-HIVGag specifically targets epidermal LCs and induces rapid changes in the LC network, including LC activation and migration out of the epidermis. Vaccine targeting of LCs significantly improved anti-HIV immune response without requirement of an adjuvant. Although the co-injection of the TLR-7/8 synthetic ligand, R-848 (resiquimod), with the vaccine, did not enhance significantly the antibody response, it stimulated recruitment of HLA-DR+ inflammatory cells to the site of immunization. This study allowed us to characterize the dynamics of early local events following the injection of a vaccine-targeted epidermal LCs and R-848. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Antitumor immune responses mediated by dendritic cells

PubMed Central

Spel, Lotte; Boelens, Jaap-Jan; Nierkens, Stefan; Boes, Marianne

2013-01-01

Dendritic cells (DCs) are essential for the induction of adaptive immune responses against malignant cells by virtue of their capacity to effectively cross-present exogenous antigens to T lymphocytes. Dying cancer cells are indeed a rich source of antigens that may be harnessed for the development of DC-based vaccines. In particular, malignant cells succumbing to apoptosis, rather than necrosis, appear to release antigens in a manner that allows for the elicitation of adaptive immune responses. In this review, we describe the processes that mediate the cross-presentation of antigens released by apoptotic cancer cells to CD8+ T lymphocytes, resulting in the activation of protective tumor-specific immune responses. PMID:24482744

Immune Interventions to Eliminate the HIV Reservoir.

PubMed

Hsu, Denise C; Ananworanich, Jintanat

2017-10-26

Inducing HIV remission is a monumental challenge. A potential strategy is the "kick and kill" approach where latently infected cells are first activated to express viral proteins and then eliminated through cytopathic effects of HIV or immune-mediated killing. However, pre-existing immune responses to HIV cannot eradicate HIV infection due to the presence of escape variants, inadequate magnitude, and breadth of responses as well as immune exhaustion. The two major approaches to boost immune-mediated elimination of infected cells include enhancing cytotoxic T lymphocyte mediated killing and harnessing antibodies to eliminate HIV. Specific strategies include increasing the magnitude and breadth of T cell responses through therapeutic vaccinations, reversing the effects of T cell exhaustion using immune checkpoint inhibition, employing bispecific T cell targeting immunomodulatory proteins or dual-affinity re-targeting molecules to direct cytotoxic T lymphocytes to virus-expressing cells and broadly neutralizing antibody infusions. Methods to steer immune responses to tissue sites where latently infected cells are located need to be further explored. Ultimately, strategies to induce HIV remission must be tolerable, safe, and scalable in order to make a global impact.

NKT Cell Networks in the Regulation of Tumor Immunity

PubMed Central

Robertson, Faith C.; Berzofsky, Jay A.; Terabe, Masaki

2014-01-01

CD1d-restricted natural killer T (NKT) cells lie at the interface between the innate and adaptive immune systems and are important mediators of immune responses and tumor immunosurveillance. These NKT cells uniquely recognize lipid antigens, and their rapid yet specific reactions influence both innate and adaptive immunity. In tumor immunity, two NKT subsets (type I and type II) have contrasting roles in which they not only cross-regulate one another, but also impact innate immune cell populations, including natural killer, dendritic, and myeloid lineage cells, as well as adaptive populations, especially CD8+ and CD4+ T cells. The extent to which NKT cells promote or suppress surrounding cells affects the host’s ability to prevent neoplasia and is consequently of great interest for therapeutic development. Data have shown the potential for therapeutic use of NKT cell agonists and synergy with immune response modifiers in both pre-clinical studies and preliminary clinical studies. However, there is room to improve treatment efficacy by further elucidating the biological mechanisms underlying NKT cell networks. Here, we discuss the progress made in understanding NKT cell networks, their consequent role in the regulation of tumor immunity, and the potential to exploit that knowledge in a clinical setting. PMID:25389427

Balancing Immune Protection and Immune Pathology by CD8+ T-Cell Responses to Influenza Infection

PubMed Central

Duan, Susu; Thomas, Paul G.

2016-01-01

Influenza A virus (IAV) is a significant human pathogen causing annual epidemics and periodic pandemics. CD8+ cytotoxic T lymphocyte (CTL)-mediated immunity contributes to the clearance of virus-infected cells, and CTL immunity targeting the conserved internal proteins of IAVs is a key protection mechanism when neutralizing antibodies are absent during heterosubtypic IAV infection. However, CTL infiltration into the airways, its cytotoxicity, and the effects of produced proinflammatory cytokines can cause severe lung tissue injury, thereby contributing to immunopathology. Studies have discovered complicated and exquisite stimulatory and inhibitory mechanisms that regulate CTL magnitude and effector activities during IAV infection. Here, we review the state of knowledge on the roles of IAV-specific CTLs in immune protection and immunopathology during IAV infection in animal models, highlighting the key findings of various requirements and constraints regulating the balance of immune protection and pathology involved in CTL immunity. We also discuss the evidence of cross-reactive CTL immunity as a positive correlate of cross-subtype protection during secondary IAV infection in both animal and human studies. We argue that the effects of CTL immunity on protection and immunopathology depend on multiple layers of host and viral factors, including complex host mechanisms to regulate CTL magnitude and effector activity, the pathogenic nature of the IAV, the innate response milieu, and the host historical immune context of influenza infection. Future efforts are needed to further understand these key host and viral factors, especially to differentiate those that constrain optimally effective CTL antiviral immunity from those necessary to restrain CTL-mediated non-specific immunopathology in the various contexts of IAV infection, in order to develop better vaccination and therapeutic strategies for modifying protective CTL immunity. PMID:26904022

Engineering synthetic vaccines using cues from natural immunity

PubMed Central

Irvine, Darrell J.; Swartz, Melody A.; Szeto, Gregory L.

2014-01-01

Vaccines aim to protect against or treat diseases through manipulation of the immune response, promoting either immunity or tolerance. The former generate antibodies and T-cells poised to protect against future pathogen encounter or attack diseased cells such as tumors; the latter, which are far less developed, block pathogenic autoreactive T-cells and autoantibodies that target self tissue. Enormous challenges remain, however, as a consequence of our incomplete understanding of human immunity. A rapidly growing field of research is the design of synthetic materials in vaccines to 1) target organs, tissues, cells, or intracellular compartments; 2) co-deliver immunomodulatory signals that control the quality of the immune response; or 3) directly act as immune regulators, and there exists great potential for well-defined materials to further our understanding of immunity. Here we describe recent advances in the design of synthetic materials to direct immune responses, highlighting successes and challenges in prophylactic, therapeutic, and tolerance-inducing vaccines. PMID:24150416

Engineering synthetic vaccines using cues from natural immunity.

PubMed

Irvine, Darrell J; Swartz, Melody A; Szeto, Gregory L

2013-11-01

Vaccines aim to protect against or treat diseases through manipulation of the immune response, promoting either immunity or tolerance. In the former case, vaccines generate antibodies and T cells poised to protect against future pathogen encounter or attack diseased cells such as tumours; in the latter case, which is far less developed, vaccines block pathogenic autoreactive T cells and autoantibodies that target self tissue. Enormous challenges remain, however, as a consequence of our incomplete understanding of human immunity. A rapidly growing field of research is the design of vaccines based on synthetic materials to target organs, tissues, cells or intracellular compartments; to co-deliver immunomodulatory signals that control the quality of the immune response; or to act directly as immune regulators. There exists great potential for well-defined materials to further our understanding of immunity. Here we describe recent advances in the design of synthetic materials to direct immune responses, highlighting successes and challenges in prophylactic, therapeutic and tolerance-inducing vaccines.

Engineering synthetic vaccines using cues from natural immunity

NASA Astrophysics Data System (ADS)

Irvine, Darrell J.; Swartz, Melody A.; Szeto, Gregory L.

2013-11-01

Vaccines aim to protect against or treat diseases through manipulation of the immune response, promoting either immunity or tolerance. In the former case, vaccines generate antibodies and T cells poised to protect against future pathogen encounter or attack diseased cells such as tumours; in the latter case, which is far less developed, vaccines block pathogenic autoreactive T cells and autoantibodies that target self tissue. Enormous challenges remain, however, as a consequence of our incomplete understanding of human immunity. A rapidly growing field of research is the design of vaccines based on synthetic materials to target organs, tissues, cells or intracellular compartments; to co-deliver immunomodulatory signals that control the quality of the immune response; or to act directly as immune regulators. There exists great potential for well-defined materials to further our understanding of immunity. Here we describe recent advances in the design of synthetic materials to direct immune responses, highlighting successes and challenges in prophylactic, therapeutic and tolerance-inducing vaccines.

'Stealth' nanoparticles evade neural immune cells but also evade major brain cell populations: Implications for PEG-based neurotherapeutics.

PubMed

Jenkins, Stuart I; Weinberg, Daniel; Al-Shakli, Arwa F; Fernandes, Alinda R; Yiu, Humphrey H P; Telling, Neil D; Roach, Paul; Chari, Divya M

2016-02-28

Surface engineering to control cell behavior is of high interest across the chemical engineering, drug delivery and biomaterial communities. Defined chemical strategies are necessary to tailor nanoscale protein interactions/adsorption, enabling control of cell behaviors for development of novel therapeutic strategies. Nanoparticle-based therapies benefit from such strategies but particle targeting to sites of neurological injury remains challenging due to circulatory immune clearance. As a strategy to overcome this barrier, the use of stealth coatings can reduce immune clearance and prolong circulatory times, thereby enhancing therapeutic capacity. Polyethylene glycol (PEG) is the most widely-used stealth coating and facilitates particle accumulation in the brain. However, once within the brain, the mode of handling of PEGylated particles by the resident immune cells of the brain itself (the 'microglia') is unknown. This is a critical question as it is well established that microglia avidly sequester nanoparticles, limiting their bioavailability and posing a major translational barrier. If PEGylation can be proved to promote evasion of microglia, then this information will be of high value in developing tailored nanoparticle-based therapies for neurological applications. Here, we have conducted the first comparative study of uptake of PEGylated particles by all the major (immune and non-immune) brain cell types. We prove for the first time that PEGylated nanoparticles evade major brain cell populations - a phenomenon which will enhance extracellular bioavailability. We demonstrate changes in protein coronas around these particles within biological media, and discuss how surface chemistry presentation may affect this process and subsequent cellular interactions. Copyright © 2016 Elsevier B.V. All rights reserved.

Cellular Immune Responses against Simian T-Lymphotropic Virus Type 1 Target Tax in Infected Baboons

PubMed Central

Castro, Iris; Giret, Teresa M.; Magnani, Diogo M.; Maxwell, Helen S.; Umland, Oliver; Perry, Jessica K.; Pecotte, Jerilyn K.; Brasky, Kathleen M.; Barber, Glen N.; Desrosiers, Ronald C.

2016-01-01

ABSTRACT There are currently 5 million to 10 million human T-lymphotropic virus type 1 (HTLV-1)-infected people, and many of them will develop severe complications resulting from this infection. A vaccine is urgently needed in areas where HTLV-1 is endemic. Many vaccines are best tested in nonhuman primate animal models. As a first step in designing an effective HTLV-1 vaccine, we defined the CD8+ and CD4+ T cell response against simian T-lymphotropic virus type 1 (STLV-1), a virus closely related to HTLV-1, in olive baboons (Papio anubis). Consistent with persistent antigenic exposure, we observed that STLV-1-specific CD8+ T cells displayed an effector memory phenotype and usually expressed CD107a, gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α). To assess the viral targets of the cellular immune response in STLV-1-infected animals, we used intracellular cytokine staining to detect responses against overlapping peptides covering the entire STLV-1 proteome. Our results show that, similarly to humans, the baboon CD8+ T cell response narrowly targeted the Tax protein. Our findings suggest that the STLV-1-infected baboon model may recapitulate some of the important aspects of the human response against HTLV-1 and could be an important tool for the development of immune-based therapy and prophylaxis. IMPORTANCE HTLV-1 infection can lead to many different and often fatal conditions. A vaccine deployed in areas of high prevalence might reduce the incidence of HTLV-1-induced disease. Unfortunately, there are very few animal models of HTLV-1 infection useful for testing vaccine approaches. Here we describe cellular immune responses in baboons against a closely related virus, STLV-1. We show for the first time that the immune response against STLV-1 in naturally infected baboons is largely directed against the Tax protein. Similar findings in humans and the sequence similarity between the human and baboon viruses suggest that the STLV-1-infected baboon

Cancer-Targeted Oncolytic Adenoviruses for Modulation of the Immune System.

PubMed

Cerullo, Vincenzo; Capasso, Cristian; Vaha-Koskela, Markus; Hemminki, Otto; Hemminki, Akseli

2018-01-01

Adenovirus is one of the most commonly used vectors for gene therapy and it is the first approved virus-derived drug for treatment of cancer. As an oncolytic agent, it can induce lysis of infected cells, but it can also engage the immune system, promoting activation and maturation of antigen- presenting cells (APCs). In essence, oncolysis combined with the associated immunostimulatory actions result in a "personalized in situ vaccine" for each patient. In order to take full advantage of these features, we should try to understand how adenovirus interacts with the immune system, what are the receptors involved in triggering subsequent signals and which kind of responses they elicit. Tackling these questions will give us further insight in how to manipulate adenovirus-mediated immune responses for enhancement of anti-tumor efficacy. In this review, we first highlight how oncolytic adenovirus interacts with the innate immune system and its receptors such as Toll-like receptors, nucleotide-binding and oligomerization domain (NOD)- like receptors and other immune sensors. Then we describe the effect of these interactions on the adaptive immune system and its cells, especially B and T lymphocytes. Finally, we summarize the most significant preclinical and clinical results in the field of gene therapy where researchers have engineered adenovirus to manipulate the host immune system by expressing cytokines and signalingmediators. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Innate Lymphoid Cells in Tumor Immunity.

PubMed

van Beek, Jasper J P; Martens, Anne W J; Bakdash, Ghaith; de Vries, I Jolanda M

2016-02-25

Innate lymphoid cells (ILCs) are a group of immune cells of the lymphoid lineage that do not possess antigen specificity. The group includes natural killer (NK) cells, lymphoid tissue inducer (LTi) cells and the recently identified ILC1s, ILC2s and ILC3s. Although the role of NK cells in the context of cancer has been well established, the involvement of other ILC subsets in cancer progression and resistance is just emerging. Here, we review the literature on the role of the different ILC subsets in tumor immunity and discuss its implications for cancer treatment and monitoring.

Innate Lymphoid Cells in Tumor Immunity

PubMed Central

van Beek, Jasper J. P.; Martens, Anne W. J.; Bakdash, Ghaith; de Vries, I. Jolanda M.

2016-01-01

Innate lymphoid cells (ILCs) are a group of immune cells of the lymphoid lineage that do not possess antigen specificity. The group includes natural killer (NK) cells, lymphoid tissue inducer (LTi) cells and the recently identified ILC1s, ILC2s and ILC3s. Although the role of NK cells in the context of cancer has been well established, the involvement of other ILC subsets in cancer progression and resistance is just emerging. Here, we review the literature on the role of the different ILC subsets in tumor immunity and discuss its implications for cancer treatment and monitoring. PMID:28536374

Effects of selective type I and II adrenal steroid agonists on immune cell distribution.

PubMed

Miller, A H; Spencer, R L; hassett, J; Kim, C; Rhee, R; Ciurea, D; Dhabhar, F; McEwen, B; Stein, M

1994-11-01

results indicate that effects of adrenal steroids on immune cell distribution are dependent on the receptor subtype involved as well as the specific cell type targeted. These factors allow for varied and complex effects of adrenal steroids on the immune system under physiological conditions.

TRIBUTYLTIN ALTERS SECRETION OF INTERLEUKIN 1 BETA FROM HUMAN IMMUNE CELLS

PubMed Central

Brown, Shyretha; Whalen, Margaret

2014-01-01

Tributyltin (TBT) has been used as a biocide in industrial applications such as wood preservation, antifouling paint, and antifungal agents. Due to its many uses, it contaminates the environment and has been found in human blood samples. Interleukin 1 beta (IL-1β) is a pro-inflammatory cytokine that promotes cell growth, tissue repair, and immune response regulation. Produced predominately by both monocytes and macrophages, IL-1β appears to increase the invasiveness of certain tumors. This study shows that TBT modifies the secretion of IL-1β from increasingly reconstituted preparations of human immune cells. IL-1β secretion was examined after 24h, 48h, or 6 day exposures to TBT in highly enriched human NK cells, monocyte-depleted (MD) peripheral blood mononuclear cells (MD-PBMCs), PBMCs, granulocytes, and a preparation combining both PBMCs and granulocytes (PBMCs+granulocytes). TBT altered IL-1β secretion from all of the cells preparations. The 200 nM concentration of TBT normally blocked the secretion of IL-1β, while lower concentrations (usually 5-50 nM) elevated secretion of IL-1β. Examination of the signaling pathway(s) responsible for the elevated secretion of IL-1β were carried out in MD-PBMCs. Pathways examined were IL-1β processing (Caspase-1), mitogen-activated protein kinases (MAPKs), and nuclear factor kappa B (NFκB). Results indicated that MAPK pathways (p44/42 and p38) appear to be the targets of TBT that lead to increased IL-1β secretion from immune cells. These results from human immune cells show IL-1β dysregulation by TBT is occurring ex vivo. Thus, potential for in vivo effects on pro-inflammatory cytokine levels may possibly be a consequence of TBT exposures. PMID:25382723

Tributyltin alters secretion of interleukin 1 beta from human immune cells.

PubMed

Brown, Shyretha; Whalen, Margaret

2015-08-01

Tributyltin (TBT) has been used as a biocide in industrial applications such as wood preservation, antifouling paint and antifungal agents. Owing to its many uses, it contaminates the environment and has been found in human blood samples. Interleukin-1 beta (IL-1β) is a pro-inflammatory cytokine that promotes cell growth, tissue repair and immune response regulation. Produced predominately by both monocytes and macrophages, IL-1β appears to increase the invasiveness of certain tumors. This study shows that TBT modifies the secretion of IL-1β from increasingly reconstituted preparations of human immune cells. IL-1β secretion was examined after 24-, 48-h or 6-day exposures to TBT in highly enriched human natural killer (NK) cells, monocyte-depleted peripheral blood mononuclear cells (MD-PBMCs), PBMCs, granulocytes and a preparation combining both PBMCs and granulocytes (PBMCs+granulocytes). TBT altered IL-1β secretion from all of the cell preparations. The 200 nM concentration of TBT normally blocked the secretion of IL-1β, whereas lower concentrations (usually 5-50 nM) elevated secretion of IL-1β. Examination of the signaling pathway(s) responsible for the elevated secretion of IL-1β was carried out in MD-PBMCs. Pathways examined were IL-1β processing (Caspase-1), mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NFκB). Results indicated that MAPK pathways (p44/42 and p38) appear to be the targets of TBT that lead to increased IL-1β secretion from immune cells. These results from human immune cells show IL-1β dysregulation by TBT is occurring ex vivo. Thus, the potential for in vivo effects on pro-inflammatory cytokine levels may possibly be a consequence of TBT exposures. Copyright © 2014 John Wiley & Sons, Ltd.

Enhanced mucosal and systemic immune response with intranasal immunization of mice with HIV peptides entrapped in PLG microparticles in combination with Ulex Europaeus-I lectin as M cell target.

PubMed

Manocha, Monika; Pal, Pramod Chandra; Chitralekha, K T; Thomas, Beena Elizabeth; Tripathi, Vinita; Gupta, Siddhartha Dutta; Paranjape, Ramesh; Kulkarni, Smita; Rao, D Nageswara

2005-12-01

The predominant route of HIV infection is through the sexual transmission via M cells. Most of the peptide and protein vaccines show poor transport across the epithelial barrier and are commonly administered by parenteral route. In the present study four HIV peptides from envelope (gp 41-LZ (leucine zipper), gp 41-FD (fusion domain) and gp120-C2) and regulatory (Nef) region in poly lactic-co-glycolide (PLG) micro-particle delivery were evaluated in mice of outbred and with different genetic background to compare immune response versus MHC restriction. Out of the combinational and single routes of immunization attempted, the single route maintained the IgG, IgA and sIgA in sera and washes for longer duration as compared to combinational routes in which the response was declined. The study demonstrated that single intranasal immunization offered significantly higher immune response (p<0.05) over oral and rectal mucosal routes in terms of inducing systemic as well as mucosal response. Also, the specific activity measurement of IgA and IgG in sera and sIgA in washes were correlating to the antibody titers. However, the intramuscular route of immunization generated systemic response only. The entrapment of plant lectin UEA-1 a ligand specific for M cells in micro-particle further enhanced the immune response in all the mucosal routes. The IgG isotypes generated were of IgG1 and IgG2a/2b in sera for all the peptides. The T cell proliferation response study with and without UEA-1 lectin in micro-particles showed significantly high (p<0.05) stimulation index (SI) with intranasal immunization for all the peptides from cells collected from spleen (SP), peyer's patches (PP) and lamina propria (LP) with SI in the order LP cells>PP>or=SP. The cytokine measurement profile of IL-2, IFN-gamma and IL-6 and low levels of IL-4 in the cultural supernatants of SP, PP and LP showed mixed CD4(+) Th1 and Th2 immune response. The p24 assay showed high percent inhibition of HIV-IIIB virus

Trispecific antibodies for CD16A-directed NK cell engagement and dual-targeting of tumor cells.

PubMed

Gantke, Thorsten; Weichel, Michael; Herbrecht, Carmen; Reusch, Uwe; Ellwanger, Kristina; Fucek, Ivica; Eser, Markus; Müller, Thomas; Griep, Remko; Molkenthin, Vera; Zhukovsky, Eugene A; Treder, Martin

2017-09-01

Bispecific antibodies that redirect the lytic activity of cytotoxic immune effector cells, such as T- and NK cells, onto tumor cells have emerged as a highly attractive and clinically validated treatment modality for hematological malignancies. Advancement of this therapeutic concept into solid tumor indications, however, is hampered by the scarcity of targetable antigens that are surface-expressed on tumor cells but demonstrate only limited expression on healthy tissues. To overcome this limitation, the concept of dual-targeting, i.e. the simultaneous targeting of two tumor-expressed surface antigens with limited co-expression on non-malignant cells, with multispecific antibodies has been proposed to increase tumor selectivity of antibody-induced effector cell cytotoxicity. Here, a novel CD16A (FcγRIIIa)-directed trispecific, tetravalent antibody format, termed aTriFlex, is described, that is capable of redirecting NK cell cytotoxicity to two surface-expressed antigens. Using a BCMA/CD200-based in vitro model system, the potential use of aTriFlex antibodies for dual-targeting and selective induction of NK cell-mediated target cell lysis was investigated. Bivalent bispecific target cell binding was found to result in significant avidity gains and up to 17-fold increased in vitro potency. These data suggest trispecific aTriFlex antibodies may support dual-targeting strategies to redirect NK cell cytotoxicity with increased selectivity to enable targeting of solid tumor antigens. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Innate Immune Cells in Liver Inflammation

PubMed Central

Liaskou, Evaggelia; Wilson, Daisy V.; Oo, Ye H.

2012-01-01

Innate immune system is the first line of defence against invading pathogens that is critical for the overall survival of the host. Human liver is characterised by a dual blood supply, with 80% of blood entering through the portal vein carrying nutrients and bacterial endotoxin from the gastrointestinal tract. The liver is thus constantly exposed to antigenic loads. Therefore, pathogenic microorganism must be efficiently eliminated whilst harmless antigens derived from the gastrointestinal tract need to be tolerized in the liver. In order to achieve this, the liver innate immune system is equipped with multiple cellular components; monocytes, macrophages, granulocytes, natural killer cells, and dendritic cells which coordinate to exert tolerogenic environment at the same time detect, respond, and eliminate invading pathogens, infected or transformed self to mount immunity. This paper will discuss the innate immune cells that take part in human liver inflammation, and their roles in both resolution of inflammation and tissue repair. PMID:22933833

The Distinctive Sensitivity to Microgravity of Immune Cell Subpopulations

NASA Astrophysics Data System (ADS)

Chen, Hui; Luo, Haiying; Liu, Jing; Wang, Peng; Dong, Dandan; Shang, Peng; Zhao, Yong

2015-11-01

Immune dysfunction in astronauts is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. However, it is unclear which subpopulations of immune cells including innate and adaptive immune cells are more sensitive to microgravity We herein investigated the direct effects of modeled microgravity (MMg) on different immune cells in vitro. Mouse splenocytes, thymocytes and bone marrow cells were exposed to MMg for 16 hrs. The survival and the phenotypes of different subsets of immune cells including CD4+T cells, CD8+T cells, CD4+Foxp3+ regulatory T cells (Treg), B cells, monocytes/macrophages, dendritic cells (DCs), natural killer cells (NK) were determined by flow cytometry. After splenocytes were cultured under MMg for 16h, the cell frequency and total numbers of monocytes, macrophages and CD4+Foxp3+T cells were significantly decreased more than 70 %. MMg significantly decreased the cell numbers of CD8+ T cells, B cells and neutrophils in splenocytes. The cell numbers of CD4+T cells and NK cells were unchanged significantly when splenocytes were cultured under MMg compared with controls. However, MMg significantly increased the ratio of mature neutrophils to immature neutrophils in bone marrow and the cell number of DCs in splenocytes. Based on the cell survival ability, monocytes, macrophages and CD4+Foxp3+Treg cells are most sensitive to microgravity; CD4+T cells and NK cells are resistant to microgravity; CD8+T cells and neutrophils are impacted by short term microgravity exposure. Microgravity promoted the maturation of neutrophils and development of DCs in vitro. The present studies offered new insights on the direct effects of MMg on the survival and homeostasis of immune cell subsets.

"Kill" the messenger: Targeting of cell-derived microparticles in lupus nephritis.

PubMed