CLONOTYPIC ANALYSIS OF T-CELLS INFILTRATING THE SKIN OF PATIENTS WITHATOPIC-DERMATITIS - EVIDENCE FOR ANTIGEN-DRIVEN ACCUMULATION OF T-CELLS

Atopic dermatitis (AD) is a chronic inflammation of the skin character ized by marked infiltration of lymphocytes, suggesting an important ro le for cellular immune responses in the pathogenesis of AD. It is stil l unclear, however, whether accumulation of lymphocytes results from a ntigen-driven mechanisms or by nonspecific inflammatory processes. We applied a novel method of T cell clonotypic analysis, using a combinat ion of reverse transcriptase-PCR with multiple T cell receptor (TCR) p rimers and subsequent single-strand conformation polymorphism (SSCP). Using this method, we were able to detect oligoclonal accumulation of T cells in inflamed skin areas of patients with AD, but not in normal skin. Identical T cell clones with the same antigen specificities were present in samples obtained from separate skin regions. Our results i ndicate that antigen(s) that exist in large areas of the skin stimulat e and expand a relatively restricted number of antigen-specific T cell s, leading to oligoclonal accumulation of T cells. We suggest chat a m arked antigen-driven infiltration of T cells is present in AD.