HIV-specific CD8 T cells express low levels of IL-7Ralpha: implications for HIV-specific T cell memory.
Wherry EJ., Day CL., Draenert R., Miller JD., Kiepiela P., Woodberry T., Brander C., Addo M., Klenerman P., Ahmed R., Walker BD.
Chronic infections in mice can result in defects in memory CD8 T cell properties including low expression of the IL-7Ralpha (CD127). To determine whether defects in memory CD8 T cell formation exist during human chronic infections and to what extent these defects may be allele- or epitope-specific, we compared influenza (Flu), vaccinia (VV) and EBV-specific CD8 T cells to HIV-specific CD8 T cells, using a panel of 13 HIV tetramers. Compared to Flu, VV or EBV, HIV tetramer+ CD8 T cells expressed significantly lower levels of CD127, and this reduction was pervasive across all epitopes and alleles tested and over a wide range of viral loads and CD4 counts. These results indicate impaired HIV-specific memory CD8 T cell differentiation, regardless of level of control of viremia, epitopes targeted or restricting HLA alleles.