CD4 and tuberculosis: Interestingly, the expression of HLA-DR and CD27 on Mtb-specific CD4+ T cells demonstrated a dichotomous profile: the Mtb-specific CD27- CD153- HLA-DR+ CD4+ T cells associated with TB status and the Mtb-specific CD27+ CD153- HLA- DR- CD4+ T cells associated to TBI status, indicating a highly differentiated profile in patients with TB (24).