Feline immunodeficiency virus (FIV) causes progressive immunodeficiency in domestic cats, with clinical course dependent on virus strain. For example, clade A FIV-PPR is predominantly neurotropic and causes a mild disease in the periphery, whereas clade C FIV-C36 causes fulminant disease with CD4(+) T-cell depletion and neutropenia but no significant pathology in the central nervous system. In order to map pathogenic determinants, chimeric viruses were prepared between FIV-C36 and FIV-PPR, with reciprocal exchanges involving (i) the 3' halves of the viruses, including the Vif, OrfA, and Env genes; (ii) the 5' end extending from the 5' long terminal repeat (LTR) to the beginning of the capsid (CA)-coding region; and (iii) the 3' LTR and Rev2-coding regions.
View Article and Find Full Text PDFHuman immunodeficiency virus (HIV), the causative agent for acquired immune deficiency syndrome, was described over 25 y ago. Since that time, much progress has been made in characterizing the pathogenesis, etiology, transmission, and disease syndromes resulting from this devastating pathogen. However, despite decades of study by many investigators, basic questions about HIV biology still remain, and an effective prophylactic vaccine has not been developed.
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