doi:10.1038/nindia.2011.78 Published online 31 May 2011
The CD4+T regulatory cells, which coordinate immune response in viral infections, might work in various ways to control activated lymphocytes — white blood cells important for the immune system — researchers working on the Chandipura virus have found.
The Chandipura virus infection is associated with acute encephalitis and severe fatality in young children. Like most other viral attacks, it reduces the CD4+, CD8+ and CD19+ cell counts drastically. It also depletes the lymphocytes in the spleen.
After encountering the virus, the lymphocytes become activated and proliferate to eliminate it. The activated T lymphocytes are continuously generated during immune response against infection.
The researchers purified CD4+ T cells from Chandipura virus-infected mice. They studied antigen specificity and ability to suppress the proliferation of other lymphocytes in vitro by purified CD4+CD25+T regulatory cells from infected mice.
The researchers found that there are several mechanisms like generation of regulatory cells and activation induced cell death (ACID) that controlled the activation of the lymphocytes and maintained cellular homeostasis.