Human T Cell Leukemia Virus Type 1 Up‐Regulation after Simian Immunodeficiency Virus–1 Coinfection in the Nonhuman Primate

Section of Infectious Diseases, Tulane University, New Orleans, Louisiana, United States
The Journal of Infectious Diseases (Impact Factor: 6). 03/2007; 195(4):562-71. DOI: 10.1086/510914
Source: PubMed


The effects that human T cell leukemia virus (HTLV) type 1 and simian immunodeficiency virus (SIV) coinfection have on HTLV-1 dynamics and disease progression were tested in a nonhuman primate model. Seven rhesus macaques were experimentally inoculated with HTLV-1, and a persistent infection was established. Coinfection with SIV/smB670 resulted in increased HTLV-1 p19 antigens in peripheral blood mononuclear cells and HTLV-1 proviral loads. Circulating CD2(+) and CD8(+) T lymphocytes increased over preinoculation levels, along with a progressive decrease in CD4(+) T cells, typical for terminal SIV disease. Finally documented was the striking emergence of up to 19% of HTLV-associated "flower cell" lymphocytes in the circulation, as seen in patients with adult T cell leukemia/lymphoma. CD8(+)CD25(+) T cell subpopulation increases were positively correlated with flower cell appearance and suggested their possible role in this process. We conclude that SIV may have the potential to up-regulate HTLV-1 and disease expression.

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Available from: Vicki L Traina-Dorge, Aug 14, 2015
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