Source: Wistar Institute
Date: August 6, 2009
A team of researchers from The Wistar Institute has identified a protein that could serve as a target for reprogramming immune system cells exhausted by exposure to chronic viral infection into more effective “soldiers” against certain viruses like HIV, hepatitis C, and hepatitis B, as well as some cancers, such as melanoma.
Effective response by key immune cells in the body, called T cells, is crucial for control of many widespread chronic viral infections such as HIV and hepatitis B and C. Virus-specific CD8 T cells, also known as “killer” T cells, often lose their ability to control viral replication and become less effective over time, a process known as T cell exhaustion. Understanding how optimal antiviral T cell responses are suppressed in these circumstances is crucial to developing strategies to prevent and treat such persisting infections.
In the August 6 on-line issue of Immunity, the research team led by Wistar assistant professor E. John Wherry, Ph.D., describes how the protein Blimp-1 (B-lymphocyte-induced maturation protein 1) represses the normal differentiation of CD8 T cells into memory T cells, which recognize disease-causing agents from previous infections and enable the body to mount faster, stronger immune responses. The team also reports that Blimp-1 causes exhausted CD8 T cells to express inhibitory receptors, which prevent recognition of specific antigens, further weakening immune response.
