scholarly journals Immunological studies of T-cell receptors. I. Specifically induced resistance to graft-versus-host disease in rats mediated by host T-cell immunity to alloreactive parental T cells.

1978 ◽  
Vol 148 (1) ◽  
pp. 103-114 ◽  
Author(s):  
D Bellgrau ◽  
D B Wilson

The present studies extend our previous efforts to understand the immunological basis of specifically induced graft-versus-host (GVH) resistance in F1 hybrid rats. Immunization of F1 rats with alloreactive T-cell populations of parental strain origin induces a host-mediated T-cell response which is specific for anti-major hostocompatibility complex receptors on parental T cells. This protective immunity is rapid in onset and once induced, it provides a highly effective, specific resistance to lethal GVH disease which is radioresistant and can be adoptively transferred to syngeneic recipients.

2010 ◽  
Vol 79 (1) ◽  
pp. 421-430 ◽  
Author(s):  
Alexandra G. Fraga ◽  
Andrea Cruz ◽  
Teresa G. Martins ◽  
Egídio Torrado ◽  
Margarida Saraiva ◽  
...  

ABSTRACTBuruli ulcer is a neglected infectious disease caused byMycobacterium ulceransand is characterized by necrotic cutaneous lesions induced by the exotoxin mycolactone. Despite evidence of Th1-mediated protective immunity,M. ulceransinfection has been associated with systemic immunosuppression. We show that early during mouse infection with either mycolactone-positive or negative strains, pathogen-specific gamma interferon (IFN-γ)-producing T cells developed in the draining lymph node (DLN). CD4+cells migrated to the infection foci, but progressive infection with virulentM. ulceransled to the local depletion of recruited cells. Moreover, dissemination of virulentM. ulceransto the DLN was accompanied by extensive DLN apoptotic cytopathology, leading to depletion of CD4+T cells and abrogation of IFN-γ expression. Advanced footpad infection with virulentM. ulceransdid not induce increased susceptibility to systemic coinfection byListeria monocytogenes. These results show that infection withM. ulceransefficiently triggers a mycobacterium-specific T-cell response in the DLN and that progression of infection with highly virulentM. ulceransleads to a local and regional suppression of that immune response, but without induction of systemic immunosuppression. These results suggest that prophylactic and/or therapeutic interventions to prevent dissemination ofM. ulceransto DLN during the early phase of infection would contribute for the maintenance of protective immunity and disease control.


2021 ◽  
Vol 12 ◽  
Author(s):  
Antonella Scaglione ◽  
Silvana Opp ◽  
Alicia Hurtado ◽  
Ziyan Lin ◽  
Christine Pampeno ◽  
...  

The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 is a major global public threat. Currently, a worldwide effort has been mounted to generate billions of effective SARS-CoV-2 vaccine doses to immunize the world’s population at record speeds. However, there is still a demand for alternative effective vaccines that rapidly confer long-term protection and rely upon cost-effective, easily scaled-up manufacturing. Here, we present a Sindbis alphavirus vector (SV), transiently expressing the SARS-CoV-2 spike protein (SV.Spike), combined with the OX40 immunostimulatory antibody (αOX40) as a novel, highly effective vaccine approach. We show that SV.Spike plus αOX40 elicits long-lasting neutralizing antibodies and a vigorous T-cell response in mice. Protein binding, immunohistochemical, and cellular infection assays all show that vaccinated mice sera inhibits spike functions. Immunophenotyping, RNA Seq transcriptome profiles, and metabolic analysis indicate a reprogramming of T cells in vaccinated mice. Activated T cells were found to mobilize to lung tissue. Most importantly, SV.Spike plus αOX40 provided robust immune protection against infection with authentic coronavirus in transgenic mice expressing the human ACE2 receptor (hACE2-Tg). Finally, our immunization strategy induced strong effector memory response, potentiating protective immunity against re-exposure to SARS-CoV-2 spike protein. Our results show the potential of a new Sindbis virus-based vaccine platform to counteract waning immune response, which can be used as a new candidate to combat SARS-CoV-2. Given the T-cell responses elicited, our vaccine is likely to be effective against variants that are proving challenging, as well as serve as a platform to develop a broader spectrum pancoronavirus vaccine. Similarly, the vaccine approach is likely to be applicable to other pathogens.


1984 ◽  
Vol 160 (3) ◽  
pp. 652-658 ◽  
Author(s):  
H Kimura ◽  
A Pickard ◽  
D B Wilson

F1 hybrid (A X B) rats immunized with parental strain (A) T cells, or which recover from graft-versus-host (GVH) reactions caused by parental T cells, develop strong T cell-mediated immune responses against anti-major histocompatibility complex (MHC) receptor structures on donor T cells specific for host (MHCb) alloantigens. This immune response provides the basis for a profound and specific resistance to the subsequent induction in these animals of local or systemic GVH disease. Using subset-specific monoclonal antibodies and negative selection rosetting procedures, we attempted to determine which donor T cell subset possesses the immunogenic idiotypic markers, and which host T cell subpopulation mediates GVH resistance. We show here that the immunizing donor cell population belongs to the W3/25+ helper T cell (Th) subset, the same one that causes local GVH reactions, and that both the W3/25+ Th and the OX8+ killer/suppressor (Tk/s) subsets of host T cells are able to transfer GVH resistance to secondary F1 recipients.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Amanda W. K. AuYeung ◽  
Robert C. Mould ◽  
Ashley A. Stegelmeier ◽  
Jacob P. van Vloten ◽  
Khalil Karimi ◽  
...  

AbstractVaccination can prevent viral infections via virus-specific T cells, among other mechanisms. A goal of oncolytic virotherapy is replication of oncolytic viruses (OVs) in tumors, so pre-existing T cell immunity against an OV-encoded transgene would seem counterproductive. We developed a treatment for melanomas by pre-vaccinating against an oncolytic vesicular stomatitis virus (VSV)-encoded tumor antigen. Surprisingly, when the VSV-vectored booster vaccine was administered at the peak of the primary effector T cell response, oncolysis was not abrogated. We sought to determine how oncolysis was retained during a robust T cell response against the VSV-encoded transgene product. A murine melanoma model was used to identify two mechanisms that enable this phenomenon. First, tumor-infiltrating T cells had reduced cytopathic potential due to immunosuppression. Second, virus-induced lymphopenia acutely removed virus-specific T cells from tumors. These mechanisms provide a window of opportunity for replication of oncolytic VSV and rationale for a paradigm change in oncolytic virotherapy, whereby immune responses could be intentionally induced against a VSV-encoded melanoma-associated antigen to improve safety without abrogating oncolysis.


2021 ◽  
Author(s):  
Antonella Scaglione ◽  
Silvana Opp ◽  
Alicia Hurtado ◽  
Christine Pampeno ◽  
Ziyan Lin ◽  
...  

The COVID-19 pandemic caused by the coronavirus SARS-CoV-2 is a major global public threat. Currently, a worldwide effort has been mounted to generate billions of effective SARS-CoV-2 vaccine doses to immunize the world population at record speeds. However, there is still demand for alternative effective vaccines that rapidly confer long-term protection and rely upon cost-effective, easily scaled-up manufacturing. Here, we present a Sindbis alphavirus vector (SV), transiently expressing the SARS-CoV-2 spike protein (SV.Spike), combined with the OX40 immunostimulatory antibody (OX40) as a novel, highly effective vaccine approach. We show that SV.Spike plus αOX40 elicits long-lasting neutralizing antibodies and a vigorous T cell response in mice. Protein binding, immunohistochemical and cellular infection assays all show that vaccinated mice sera inhibits spike functions. Immunophenotyping, RNA Seq transcriptome profiles and metabolic analysis indicate a reprogramming of T cells in vaccinated mice. Activated T cells were found to mobilize to lung tissue. Most importantly, SV.Spike plus αOX40 provided robust immune protection against infection with authentic coronavirus in transgenic mice expressing the human ACE2 receptor (hACE2-Tg). Finally, our immunization strategy induced strong effector memory response, potentiating protective immunity against re-exposure to SARS-CoV-2 spike protein. Our results show the potential of a new Sindbis virus-based vaccine platform to counteract waning immune response that can be used as a new candidate to combat SARS-CoV-2. Given the strong T cell responses elicited, our vaccine is likely to be effective against variants that are proving challenging, as well as, serve as a platform to develop a broader spectrum pancoronavirus vaccine. Similarly, the vaccine approach is likely to be applicable to other pathogens.


Blood ◽  
2000 ◽  
Vol 95 (12) ◽  
pp. 3693-3701 ◽  
Author(s):  
Ypke V. J. M. van Oosterhout ◽  
Liesbeth van Emst ◽  
Anton V. M. B. Schattenberg ◽  
Wil J. M. Tax ◽  
Dirk J. Ruiter ◽  
...  

Abstract This study evaluated the anti-graft versus host disease (GVHD) potential of a combination of immunotoxins (IT), consisting of a murine CD3 (SPV-T3a) and CD7 (WT1) monoclonal antibody both conjugated to deglycosylated ricin A. In vitro efficacy data demonstrated that these IT act synergistically, resulting in an approximately 99% elimination of activated T cells at 10−8 mol/L (about 1.8 μg/mL). Because most natural killer (NK) cells are CD7+, NK activity was inhibited as well. Apart from the killing mediated by ricin A, binding of SPV-T3a by itself impaired in vitro cytotoxic T-cell cytotoxicity. Flow cytometric analysis revealed that this was due to both modulation of the CD3/T-cell receptor complex and activation-induced cell death. These results warranted evaluation of the IT combination in patients with refractory acute GVHD in an ongoing pilot study. So far, 4 patients have been treated with 3 to 4 infusions of 2 or 4 mg/m2 IT combination, administered intravenously at 48-hour intervals. The T1/2 was 6.7 hours, and peak serum levels ranged from 258 to 3210 ng/mL. Drug-associated side effects were restricted to limited edema, fever, and a modest rise of creatine kinase levels. One patient developed low-titer antibodies against ricin A. Infusions were associated with an immediate drop of circulating T cells, followed by a more gradual but continuing elimination of T/NK cells. One patient mounted an extensive CD8 T-cell response directly after treatment, not accompanied with aggravating GVHD. Two patients showed nearly complete remission of GVHD, despite unresponsiveness to the extensive pretreatment. These findings justify further investigation of the IT combination for treatment of diseases mediated by T cells.


Viruses ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 233
Author(s):  
Emma Rey-Jurado ◽  
Karen Bohmwald ◽  
Hernán G. Correa ◽  
Alexis M. Kalergis

T cells play an essential role in the immune response against the human respiratory syncytial virus (hRSV). It has been described that both CD4+ and CD8+ T cells can contribute to the clearance of the virus during an infection. However, for some individuals, such an immune response can lead to an exacerbated and detrimental inflammatory response with high recruitment of neutrophils to the lungs. The receptor of most T cells is a heterodimer consisting of α and β chains (αβTCR) that upon antigen engagement induces the activation of these cells. The αβTCR molecule displays a broad sequence diversity that defines the T cell repertoire of an individual. In our laboratory, a recombinant Bacille Calmette–Guérin (BCG) vaccine expressing the nucleoprotein (N) of hRSV (rBCG-N-hRSV) was developed. Such a vaccine induces T cells with a Th1 polarized phenotype that promote the clearance of hRSV infection without causing inflammatory lung damage. Importantly, as part of this work, the T cell receptor (TCR) repertoire of T cells expanded after hRSV infection in naïve and rBCG-N-hRSV-immunized mice was characterized. A more diverse TCR repertoire was observed in the lungs from rBCG-N-hRSV-immunized as compared to unimmunized hRSV-infected mice, suggesting that vaccination with the recombinant rBCG-N-hRSV vaccine triggers the expansion of T cell populations that recognize more viral epitopes. Furthermore, differential expansion of certain TCRVβ chains was found for hRSV infection (TCRVβ+8.3 and TCRVβ+5.1,5.2) as compared to rBCG-N-hRSV vaccination (TCRVβ+11 and TCRVβ+12). Our findings contribute to better understanding the T cell response during hRSV infection, as well as the functioning of a vaccine that induces a protective T cell immunity against this virus.


Blood ◽  
2015 ◽  
Vol 125 (4) ◽  
pp. 731-739 ◽  
Author(s):  
Rob S. Sellar ◽  
Frederick Arce Vargas ◽  
Jake Y. Henry ◽  
Stephanie Verfuerth ◽  
Sarah Charrot ◽  
...  

Key Points CMV serostatus significantly influences chimerism levels after T-cell–depleted allogeneic transplantation. CMV-specific T cells are exclusively of recipient origin after R+/D− T-cell–depleted transplants and appear to provide protective immunity.


2009 ◽  
Vol 206 (12) ◽  
pp. 2735-2745 ◽  
Author(s):  
James D. Brien ◽  
Jennifer L. Uhrlaub ◽  
Alec Hirsch ◽  
Clayton A. Wiley ◽  
Janko Nikolich-Žugich

West Nile virus (WNV) infection causes a life-threatening meningoencephalitis that becomes increasingly more prevalent over the age of 50 and is 40–50× more prevalent in people over the age of 70, compared with adults under the age of 40. In a mouse model of age-related vulnerability to WNV, we demonstrate that death correlates with increased viral titers in the brain and that this loss of virus control with age was the result of defects in the CD4 and CD8 T cell response against WNV. Specific age-related defects in T cell responses against dominant WNV epitopes were detected at the level of cytokine and lytic granule production, each of which are essential for resistance against WNV, and in the ability to generate multifunctional anti-WNV effector T cells, which are believed to be critical for robust antiviral immunity. In contrast, at the peak of the response, old and adult T cells exhibited superimposable peptide sensitivity. Most importantly, although the adult CD4 or CD8 T cells readily protected immunodeficient mice upon adoptive transfer, old T cells of either subset were unable to provide WNV-specific protection. Consistent with a profound qualitative and quantitative defect in T cell immunity, old brains contained at least 12× fewer total effector CD8 T cells compared with adult mice at the peak of brain infection. These findings identify potential targets for immunomodulation and treatment to combat lethal WNV infection in the elderly.


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