Sensitivity of HIV-1 infectivity to heat (T90) is linked to Env.

1T90, the temperature at which HIV-1 infectivity decreases by 90% in 1 h, and the standard error of the mean (SEM) of at least three independent experiments.2HIV-1 PSVs, produced by transfection of 293T cells using env expression plasmids pSVIIIexe7 (JR-CSF, JR-FL, ADA), pCAGGS (SF162, SIVmac239), pcDNA3.1 (LAI), or pVSV-G (VSV-G) in combination with the backbone vectors pSG3Δenv (clade B) or Q23Δenv (clade A).3HIV-1 MCs are LAI-chimeras (see Materials and Methods) and fully replication competent. Virions were produced by transfection of 293T cells, or through passage in MT-2/CCR5ΔCT cells, as indicated.4nd, not determined, or material unavailable.