In vitro stimulation with a non-peptidic alkylphosphate expands cells expressing V gamma 2-J gamma 1.2/V delta 2 T-cell receptors

The majority of peripheral blood gamma delta T cells in healthy adult human s express the V gamma2/V delta2 T-cell receptor (TCR) and generate TCR-medi ated, major histocompatibility complex (MHC)unrestricted proliferative resp onses to low molecular weight alkylphosphates. V gamma2/V delta2 population s after antigen proliferation maintained diversity in the CDR3s of V gamma2 mRNA, indicating that the response was polyclonal or oligoclonal, and were enriched for V gamma2 TCR chains containing the J gamma1.2 segment. Alkylp hosphate stimulation further skewed an already biased peripheral blood gamm a delta T-cell population and increased the abundance of V gamma2-J gamma1. 2/V delta2 T cell receptors, suggesting similarities between the alkylphosp hate response and peripheral selection mechanisms shaping this repertoire i n human beings.