RESUMEN
To track the sites of feline immunodeficiency virus (FIV) clearance in cats and follow viral localization from 30 min until 48 h post-intravenous inoculation, several kinds of cells (PBMC, splenocytes, thymocytes, Kupffer cells (KC), lymph nodes, bone marrow and alveolar cells) were collected. After co-culture with uninfected PBMC, p24 antigen was detected. Reverse transcription (RT)-nested PCR and PCR were performed on all these cells and in situ RT-PCR on liver, spleen and isolated KC. Biochemical determinations showed that viral RNA was predominantly found during the first hour post-infection (p.i.) in PBMC, splenocytes and KC and later on (24-48 h) in thymocytes and lymph node cells. In addition, viral DNA was detected as early as 24 h post-inoculation in splenocytes and KC, whereas PBMC were positive at 48 h. Microscopic studies confirmed the presence of viral RNA in hepatic KC and also in the splenic red pulp rich in macrophages and dendritic cells. Our results enabled the early identification of the cell population infected and highlight the role played by macrophagic cells in the uptake of FIV and in viral dissemination.