[BTLA Characterization and its association with disease progression in patients with chronic HIV-1 infection.]

To characterize the B and T lymphocyte attenuator (BTLA, CD272) expression on CD4(+); and CD8(+); T lymphocytes during chronic HIV-1 infection, and analyze the clinical significance for its expression and disease progression.

BTLA expression on T cells in peripheral blood from 34 patients with chronic HIV-1 infection and 15 healthy donors was measured using flow cytometry. The correlation between BTLA expression and CD4 T cell counts and virus load was also analyzed.

BTLA expression on both CD4 and CD8 T cells was significantly down-regulated in HIV-1-infected subjects compared to HCs and the down-regulation of BTLA expression on total T-cell subsets was associated with the progression of HIV-1 infection. BTLA expression on CD4 T cells was positively correlated with CD4 T cell counts and negatively correlated with HIV virus load.

BTLA signaling pathway may play an important role in the unbalance between the stimulating and inhibitory signal which results in the general immune activation during chronic HIV-1 infection. Manipulation of BTLA inhibitory pathway may present an alternative strategy for overcoming immune activation for this disease.