SIV and HIV-1 replication in human cells. (A) SIV and HIV-1 replication kinetics in CEM-SS cells. CEM-SS cells were infected with SIVagm (top panel), SIVmac (middle panel), and HIV-1 (bottom) in the absence (CsA[-], closed circles) or presence of 2.5 μM CsA (CsA[+], open circles). Virus production was monitored by measuring RT activity in the culture supernatants. (B) CypA incorporation into virions. Virus-containing supernatants were harvested from CsA-untreated and CsA-treated CEM-SS cells infected with SIVagm, SIVmac and HIV-1. A mock-infected sample was included as a control. CypA-specific band densities were quantified by densitometric scanning and are plotted in the lower panel. For each virus, the density of the band from CsA-untreated cells was defined as 100% and the ratio (%) of the density of the band from CsA-treated cells to that from CsA-untreated cells was calculated. The image of one representative blot is shown. (C) SIVagm replication kinetics in A3.01 cells.