2006AA02A109. 2006AA02A115); the National Natural Science Foundation of China (no. 30570771); the Beijing Ministry of Science https://www.selleckchem.com/products/DAPT-GSI-IX.html and Technology (no. D07050701350701) and the Cheung Kong Scholars programme. All disclosures were provided in the ‘Acknowledgements’ section. “
“Thomas Jefferson University, Philadelphia, PA, USA Vaccinia virus (VV) has been used globally as a vaccine to eradicate smallpox. Widespread use of this viral vaccine has been tempered in recent years
because of its immuno-evasive properties, with restrictions prohibiting VV inoculation of individuals with immune deficiencies or atopic skin diseases. VV infection is known to perturb several pathways for immune recognition including MHC class II (MHCII) and CD1d-restricted antigen presentation. MHCII and CD1d molecules associate with a conserved intracellular chaperone, CD74, also known as invariant chain. Upon VV infection, cellular Erlotinib mw CD74 levels are significantly reduced in antigen-presenting cells, consistent with the observed destabilization of MHCII molecules. In the current study, the ability of sustained CD74 expression to overcome VV-induced suppression of antigen presentation was investigated. Viral inhibition of MHCII antigen presentation could be partially ameliorated by ectopic expression of CD74 or by infection of cells with a recombinant VV encoding murine CD74 (mCD74-VV). In contrast,
virus-induced disruptions in CD1d-mediated antigen presentation persisted even with sustained CD74 expression. Mice immunized with the recombinant mCD74-VV displayed greater protection during VV challenge and more robust anti-VV antibody responses. Together, these
observations suggest that recombinant VV vaccines encoding CD74 may be useful tools to improve CD4+ T-cell responses to viral and tumour antigens. “
“TCR repertoire diversity can influence the efficacy of CD8+ T-cell populations, with greater breadth eliciting better protection. We analyzed TCRβ diversity and functional capacity for influenza-specific CD8+ T cells expressing a single TCRα chain. Mice (A7) transgenic enough for the H2KbOVA257–264-specific Vα2.7 TCR were challenged with influenza to determine how fixing this “irrelevant” TCRα affects the “public” and restricted DbNPCD8+versus the “private” and diverse DbPACD8+ responses. Though both DbNPCD8+ and DbPACD8+ sets are generated in virus-primed A7 mice, the constrained DbNPCD8+ population lacked the characteristic, public TCRVβ8.3, and consequently was reduced in magnitude and pMHC-I avidity. For the more diverse DbPACD8+ T cells, this particular forcing led to a narrowing and higher TCRβ conservation of the dominant Vβ7, though the responses were of comparable magnitude to C57BL/6J controls. Interestingly, although both the TCRβ diversity and the cytokine profiles were reduced for the DbNPCD8+ and DbPACD8+ sets in spleen, the latter measure of polyfunctionality was comparable for T cells recovered from the infected lungs of A7 and control mice.