Human leucocyte antigen‐Bw4 and Gag‐specific T cell responses are associated with slow disease progression in HIV‐1B‐infected anti‐retroviral therapy‐naive Chinese

In China, the majority of human immunodeficiency virus (HIV) infections are predominately subtype B. It is important to characterize the HIV‐1 subtype B‐specific and its T cell response within the Chinese population, with the aim of identifying protective correlates of immunity to control HIV‐1 infections. In this study, we performed a comprehensive analysis looking into the magnitude/strength of T cell responses directed at the Gag protein of the HIV‐1 subtype B, one of the most conserved HIV‐1 proteins. The study group consisted of anti‐retroviral native and chronic HIV‐1 subtype B‐infected individuals. We used enzyme‐linked immunospot (ELISPOT) assay to quantify the total T cell responses to HIV‐1 Gag at the single peptide level. Twenty‐eight (38%) peptides were recognized in 24 (82·8%) individuals. The p24 was identified as the most frequently recognized subunit protein with the greatest T cell response in the test, which correlated positively with CD4⁺ T cell count and inversely with viral load (VL). At the level of the human leucocyte antigen (HLA) supertypes, we detected the highest levels and a significant correlation with both the CD4⁺ T cell count and the VL with Gag T cell responses in Bw4/Bw4. These findings demonstrate that (i) the HIV‐1B Gag p24‐specific immune responses play an important role in controlling viral replication and slowing clinical progression; and (ii) HLA‐Bw4/Bw4 allele has stronger T cell responses, which is associated with slow clinical progression in Chinese HIV patients.