In:
Pathogens and Immunity, Case Western Reserve University, Vol. 4, No. 1 ( 2019-01-30), p. 1-
Abstract:
Background: Vaccination with the Merck human adenovirus serotype-5 (HAdV-5) vectored HIV-1 subtype B gag/pol/nef vaccine was unexpectedly associated with enhanced susceptibility to HIV-1 infection in uncircumcised HAdV-5 seropositive men. It has been hypothesized that vaccination may have resulted in activated CD4+ T lymphocytes trafficking to mucosal sites thereby increasing targets for HIV infection. We have previously shown that AdV-vector vaccination in rhesus macaques resulted in an increase in the frequency of activated mucosal CD4+ T cells. However, whether this increase in activation is sufficient to increase susceptibility to HIV/SIV infection is unclear.Methods: To examine this scenario, we developed a preliminary, proof-of-concept vaccination-challenge model in order to examine vaccine-induced SIV susceptibility in rhesus macaques. Rhesus macaques (n = 10/group) were vaccinated with a simian AdV-7 (SAdV-7)-vector encoding an irrelevant insert (SARS spike) and challenged 5 weeks post-prime in an escalating dosing regimen starting with sub-infectious doses (1:10,000 or 2TCID50) of SIVmac251.Results: In contrast to our previous study, the SAdV-7 vaccine regimen did not induce detectable mucosal CD4+ T cell activation at the time points assessed in animals obtained from a different vendor and housed in a different facility. Within the power of the study, we did not observe significantly increased SIV acquisition in SAdV-7-vaccinated (5/10) versus placebo-vaccinated (3/10) macaques after repeated low-dose intra-rectal SIVmac251 challenge (P 〈 0.2).Conclusions: These results lay groundwork for future experiments to assess vaccine-induced SIV susceptibility in rhesus macaques. Further larger-scale studies are necessary to confirm the AdV-vector vaccination associated trend towards increased SIV/HIV acquisition and clarify associated mechanisms.Keywords: vaccine; HIV; CD4; susceptibility
Type of Medium:
Online Resource
ISSN:
2469-2964
DOI:
10.20411/pai.v4i1.241
Language:
Unknown
Publisher:
Case Western Reserve University
Publication Date:
2019
detail.hit.zdb_id:
3032410-5
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