DefinePK

Abstract

A cluster of T-cell receptors includes activating and inhibitory stimulatory molecules that favorably or unfavorably control immune responses. Recent studies on chronic bovine infections have revealed that, under severe viral loads and malignant pathologies, stromal and immune cells increase the expression of immune inhibitory molecules. To maintain internal homeostasis, programmed cell death receptor-1 (PD-1) and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) inhibit T cell activity. In chronic viral infections, the prolonged activation of T cells leads to the continuous production of PD-1 and CTLA-4. Blocking PD-1 and CTLA-4 is a successful therapeutic approach that is actively used in the treatment of oncological diseases. The effectiveness of this approach in the treatment of chronic viral infections, particularly those caused by bovine leukemia virus has been hypothesized. However, uncertainty surrounds these receptors’ function in persistent viral infections. This review focused on the functions of PD-1 and CTLA-4 in bovine leukemia virus and discusses disease therapies based on their blockade.