Therefore, we measured HIV susceptibility of vaccine Env-specific CD4 T cells using the same assay and found that unlike vector-specific CD4 T cells, Env-specific CD4 T cells in both RV144 and HVTN204 PBMC were readily susceptible to R5 and X4 HIV infection with no significant difference detected (S6 Fig). Here, ERVW-1 is linked to HIV infectious disease.