Reduction of memory cytotoxic T cell numbers by heterologous viral infections: A mathematical model

1997 ◽  
Vol 56 (1-3) ◽  
pp. 254
Author(s):  
K Takumi
2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Khashayar Esfahani ◽  
Tho-Alfakar Al-Aubodah ◽  
Pamela Thebault ◽  
Réjean Lapointe ◽  
Marie Hudson ◽  
...  

Abstract Immune checkpoint inhibitor (ICI) use remains a challenge in patients with solid organ allografts as most would undergo rejection. In a melanoma patient in whom programmed-death 1 (PD-1) blockade resulted in organ rejection and colitis, the addition of the mTOR inhibitor sirolimus resulted in ongoing anti-tumor efficacy while promoting allograft tolerance. Strong granzyme B+, interferon (IFN)-γ+ CD8+ cytotoxic T cell and circulating regulatory T (Treg) cell responses were noted during allograft rejection, along with significant eosinophilia and elevated serum IL-5 and eotaxin levels. Co-treatment with sirolimus abated cytotoxic T cell numbers and eosinophilia, while elevated Treg cell numbers in the peripheral blood were maintained. Interestingly, numbers of IFN-γ+ CD4+ T cells and serum IFN-γ levels increased with the addition of sirolimus treatment likely promoting ongoing anti-PD-1 efficacy. Thus, our results indicate that sirolimus has the potential to uncouple anti-PD-1 therapy toxicity and efficacy.


Viruses ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 840 ◽  
Author(s):  
Chae Won Kim ◽  
Hye Jee Yoo ◽  
Jang Hyun Park ◽  
Ji Eun Oh ◽  
Heung Kyu Lee

Influenza is an infectious respiratory illness caused by the influenza virus. Though vaccines against influenza exist, they have limited efficacy. To additionally develop effective treatments, there is a need to study the mechanisms of host defenses from influenza viral infections. To date, the mechanism by which interleukin (IL)-33 modulates the antiviral immune response post-influenza infection is unclear. In this study, we demonstrate that exogenous IL-33 enhanced antiviral protection against influenza virus infection. Exogenous IL-33 induced the recruitment of dendritic cells, increased the secretion of pro-inflammatory cytokine IL-12, and promoted cytotoxic T-cell responses in the local microenvironment. Thus, our findings suggest a role of exogenous IL-33 in the antiviral immune response against influenza infection.


2011 ◽  
Vol 74 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Amanda Galante ◽  
Koji Tamada ◽  
Doron Levy

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shafi Mahmud ◽  
Md. Oliullah Rafi ◽  
Gobindo Kumar Paul ◽  
Maria Meha Promi ◽  
Mst. Sharmin Sultana Shimu ◽  
...  

AbstractCurrently, no approved vaccine is available against the Middle East respiratory syndrome coronavirus (MERS-CoV), which causes severe respiratory disease. The spike glycoprotein is typically considered a suitable target for MERS-CoV vaccine candidates. A computational strategy can be used to design an antigenic vaccine against a pathogen. Therefore, we used immunoinformatics and computational approaches to design a multi-epitope vaccine that targets the spike glycoprotein of MERS-CoV. After using numerous immunoinformatics tools and applying several immune filters, a poly-epitope vaccine was constructed comprising cytotoxic T-cell lymphocyte (CTL)-, helper T-cell lymphocyte (HTL)-, and interferon-gamma (IFN-γ)-inducing epitopes. In addition, various physicochemical, allergenic, and antigenic profiles were evaluated to confirm the immunogenicity and safety of the vaccine. Molecular interactions, binding affinities, and the thermodynamic stability of the vaccine were examined through molecular docking and dynamic simulation approaches, during which we identified a stable and strong interaction with Toll-like receptors (TLRs). In silico immune simulations were performed to assess the immune-response triggering capabilities of the vaccine. This computational analysis suggested that the proposed vaccine candidate would be structurally stable and capable of generating an effective immune response to combat viral infections; however, experimental evaluations remain necessary to verify the exact safety and immunogenicity profile of this vaccine.


2001 ◽  
Vol 257 (1-2) ◽  
pp. 155-161 ◽  
Author(s):  
Tobias Ostler ◽  
Karin Schamel ◽  
Tracy Hussell ◽  
Peter Openshaw ◽  
Jürgen Hausmann ◽  
...  

2020 ◽  
Vol 71 (16) ◽  
pp. 2150-2157 ◽  
Author(s):  
Yueping Liu ◽  
Yue Pan ◽  
Zhenhong Hu ◽  
Ming Wu ◽  
Chenhui Wang ◽  
...  

Abstract Background Thymosin alpha 1 (Tα1) had been used in the treatment of viral infections as an immune response modifier for many years. However, clinical benefits and the mechanism of Tα1 treatment for COVID-19 patients are still unclear. Methods We retrospectively reviewed the clinical outcomes of 76 severe COVID-19 cases admitted to 2 hospitals in Wuhan, China, from December 2019 to March 2020. The thymus output in peripheral blood mononuclear cells from COVID-19 patients was measured by T-cell receptor excision circles (TRECs). The levels of T-cell exhaustion markers programmed death-1 (PD-1) and T-cell immunoglobulin and mucin domain protein 3 (Tim-3) on CD8+ T cells were detected by flow cytometry. Results Compared with the untreated group, Tα1 treatment significantly reduced the mortality of severe COVID-19 patients (11.11% vs 30.00%, P = .044). Tα1 enhanced blood T-cell numbers in COVID-19 patients with severe lymphocytopenia. Under such conditions, Tα1 also successfully restored CD8+ and CD4+ T-cell numbers in elderly patients. Meanwhile, Tα1 reduced PD-1 and Tim-3 expression on CD8+ T cells from severe COVID-19 patients compared with untreated cases. It is of note that restoration of lymphocytopenia and acute exhaustion of T cells were roughly parallel to the rise of TRECs. Conclusions Tα1 treatment significantly reduced mortality of severe COVID-19 patients. COVID-19 patients with counts of CD8+ T cells or CD4+ T cells in circulation less than 400/μL or 650/μL, respectively, gained more benefits from Tα1. Tα1 reversed T-cell exhaustion and recovered immune reconstitution through promoting thymus output during severe acute respiratory syndrome–coronavirus 2 infection.


Blood ◽  
2006 ◽  
Vol 108 (10) ◽  
pp. 3406-3413 ◽  
Author(s):  
Sabine Mumprecht ◽  
Matthias Matter ◽  
Viktor Pavelic ◽  
Adrian F. Ochsenbein

Abstract Imatinib mesylate (imatinib) is a potent inhibitor of defined tyrosine kinases (TKs) and is effective in the treatment of malignancies characterized by constitutive activation of these TKs such as chronic myeloid leukemia and gastrointestinal stromal tumors. TKs also play an important role in T-cell receptor (TCR) signal transduction. Inhibitory as well as stimulating effects of imatinib on T cells and dendritic cells have been described. Here, we analyzed the effects of imatinib treatment on antiviral immune responses in vivo. Primary cytotoxic T-cell (CTL) responses were not impaired in imatinib-treated mice after infection with lymphocytic choriomeningitis virus (LCMV) or after immunization with a tumor cell line expressing LCMV glycoprotein (LCMV-GP). Similarly, neutralizing antibody responses to vesicular stomatitis virus (VSV) were not affected. In contrast, secondary expansion of LCMV-specific memory CTLs was reduced in vitro and in vivo, resulting in impaired protection against reinfection. In addition, imatinib treatment delayed the onset of diabetes in a CTL-induced diabetes model. In summary, imatinib treatment in vivo selectively inhibits the expansion of antigen-experienced memory CTLs without affecting primary T- or B-cell responses. Therefore, imatinib may be efficacious in the suppression of CTL-mediated immunopathology in autoimmune diseases without the risk of acquiring viral infections.


2018 ◽  
Vol 6 (3) ◽  
pp. 83-87
Author(s):  
Ming Guo

Abstract Recently, a new type of CD8+ T-cell subset, namely, the chemokine (C-X-C motif) receptor 5 (CXCR5+) cluster of differentiation (CD8+) T-cell subset (also called the follicular cytotoxic T-cell (TFC) subgroup), has been discovered around B-cell follicles. The discovery has aroused widespread interest. However, the processes and mechanisms of TFCs taking part in the immune response of the germinal center and their specific roles must still be clearly identified. This article reviews domestic and foreign studies on factors regulating the phenotype, physiological functions, maturity, and differentiation of TFCs and roles and clinical significance of these cells in HIV infection. This review has shown good application prospects for TFCs. The author believes that further studies on TFCs can provide another tool for cytotherapy to control or cure chronic viral infections or tumors.


Sign in / Sign up

Export Citation Format

Share Document