tailieunhanh - Báo cáo y học: "Acute mucosal pathogenesis of feline immunodeficiency virus is independent of viral dose in vaginally infected cats"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Retrovirology cung cấp cho các bạn kiến thức về ngành y đề tài: "Acute mucosal pathogenesis of feline immunodeficiency virus is independent of viral dose in vaginally infected cats. | Howard et al. Retrovirology 2010 7 2 http content 7 1 2 RETROVIROLOGY RESEARCH Open Access Acute mucosal pathogenesis of feline immunodeficiency virus is independent of viral dose in vaginally infected cats Kristina E Howard1 Stacie K Reckling1 Erin A Egan1 2 Gregg A Dean1 Abstract Background The mucosal pathogenesis of HIV has been shown to be an important feature of infection and disease progression. HIV-1 infection causes depletion of intestinal lamina propria CD4 T cells LPL therefore intestinal CD4 T cell preservation may be a useful correlate of protection in evaluating vaccine candidates. Vaccine studies employing the cat FIV and macaque SIV models frequently use high doses of parenterally administered challenge virus to ensure high plasma viremia in control animals. However it is unclear if loss of mucosal T cells would occur regardless of initial viral inoculum dose. The objective of this study was to determine the acute effect of viral dose on mucosal leukocytes and associated innate and adaptive immune responses. Results Cats were vaginally inoculated with a high middle or low dose of cell-associated and cell-free FIV. PBMC serum and plasma were assessed every two weeks with tissues assessed eight weeks following infection. We found that irrespective of mucosally administered viral dose FIV infection was induced in all cats. However viremia was present in only half of the cats and viral dose was unrelated to the development of viremia. Importantly regardless of viral dose all cats experienced significant losses of intestinal CD4 LPL and CD8 intraepithelial lymphocytes IEL . Innate immune responses by CD56 CD3- NK cells correlated with aviremia and apparent occult infection but did not protect mucosal T cells. CD4 and CD8 T cells in viremic cats were more likely to produce cytokines in response to Gag stimulation whereas aviremic cats T cells tended to produce cytokines in response to Env stimulation. However while cell-mediated .