Influenza virus upregulates CXCR4 expression in CD4 super(+) cells

We examined the effect of prior influenza virus infection on the susceptibility of CD4 super(+) cells to HIV-1 infection. Influenza virus infection of HeLa-CD4 cells resulted in a marked increase in susceptibility to infection by CXCR4-dependent but not CCR5-dependent HIV isolates. Influenza virus infection resulted in an increase in the steady state level of CXCR4 transcripts and an increase in cell surface CXCR4 expression. Our observations suggest that infectious agents such as influenza may contribute to HIV disease progression by modulating coreceptor availability.