Mk. Oaks et al., T-CELL RECEPTOR-ALPHA AND BETA-CHAIN GENE-EXPRESSION IN CELLS INFILTRATING HUMAN CARDIAC ALLOGRAFTS, The American journal of the medical sciences, 309(1), 1995, pp. 26-34
Intragraft T-cell receptor (TCR) ct and beta chain variable region gen
e expression was analyzed in human cardiac allograft biopsies by rever
se transcription polymerase chain reaction, Rearranged TCR alpha and b
eta chain gene transcripts were detected in all biopsies examined (N =
23), indicating the presence of T cells bearing the alpha/beta TCR ev
en in the absence of microscopically apparent leukocyte infiltration.
In this analysis, a broad TCR alpha/beta repertoire in actively reject
ing lesions was demonstrated, whereas fewer TCR alpha and beta chain g
ene families were detected in nonrejecting lesions. The number of expr
essed TCR VP chain gene families typically was two-to sixfold higher t
han that of V alpha chain families in all biopsies tested. This asymme
tric relation was present throughout the histologic grading spectrum o
f the biopsies. Based on these data, the TCR repertoire is heterogenou
s even in the early stages of mononuclear cell infiltration of the all
ograft. Also based on the data, the presence of T cells in grafts with
minimal cellular infiltrates is not a specific marker of subsequent r
ejection episode, because T cells were identified in all allograft bio
psies.