Abstract
Background: While dysfunctional exhausted CD8+ T cells hamper
viral control when children acquire hepatitis B virus (HBV) infection,
it’s crucial to recognize that CD8+ T cells have diverse phenotypes and
functions. This study explored a subset of CD8+ T cells expressing C - C
chemokine receptor type 5 (CCR5) in children with HBV infection.
Methods: 36 patients in the immune tolerant (IT) group, 33
patients in the immune active (IA) group, and 55 patients in the
combined response (CR) group were enrolled. The frequency, functional
molecules and effector functions of the CCR5+CD8+ T cells population in
different groups were evaluated. Results: The frequency of
CCR5+CD8+ T cells correlated positively with the frequency of CCR5+ CD4+
T cells and patient age, and it correlated negatively with ALT, AST, HBV
DNA, HBsAg and lactic dehydrogenase levels. CCR5+CD8+ T cells had higher
levels of inhibitory and activated receptors and produced higher levels
of IFN-γ, IL-2, and TNF-α than CCR5-CD8+ T cells.
Conclusion:CCR5+CD8+T cells were partially exhausted but
possessed a stronger antiviral activity than CCR5-CD8+T cells. The
identification of this subset increases our understanding of CD8+ T cell
functions and serve as a potential immunotherapeutic target for children
with HBV infection.