Preferential expansion of autoreactive T lymphocytes from the memory T-cell pool by IL-7.

We have developed a new technique that allows us to quantify antigen-specific T cells, and to determine their functional phenotype and origin from naive versus memory populations. Using this methodology, we have characterized a total of 286 T-cell lines specific for myelin basic protein (MBP) and influenza hemagglutinin from 16 multiple sclerosis (MS) patients and nine healthy donors. Our data support the notion that MBP-specific T cells undergo in vivo activation in MS patients and indicate a presence of immune dysregulation that renders MS patients prone to develop autoimmunity. Our methodology offers a way to study antigen-specific T-cell characteristics as a surrogate marker in immunotherapy trials.