RESTRICTED AND CONSERVED T-CELL REPERTOIRES INVOLVED IN ALLORECOGNITION OF CLASS II MAJOR HISTOCOMPATIBILITY COMPLEX

摘要

The nature of the alloreactive T-cell response is not yet clearly understood. These strong cellular responses are thought to be the basis of allograft rejection and graft-vs.-host disease. The question of the extent of responding T-cell repertoires has so far been addressed by cellular cloning, often combined with molecular T-cell receptor (TCR) analysis, Here we present a broad repertoire analysis of primed responder cells from mixed Lymphocyte cultures in which two different DR1/3 responders were stimulated with DR3/4 cells, Repertoire analysis was performed by TCR spectratyping, a method by which T cells are analyzed on the basis of the complementarity-determining region 3 length of different variable region (V) families, Strikingly, both responders showed very similar repertoires when the TCR V beta was used as a lineage marker. This was not seen when TCR V alpha was analyzed, A different pattern of TCR V beta was observed if the stimulating alloantigen was changed, This finding indicates that alloreactive T cells form a specific repertoire for each alloantigen. Since conservation appears to be linked to TCR V beta, the question of different roles of alpha and beta chains in allorecognition is raised. [References: 27]