Relationships among expression, transcription and rearrangement of T-cell receptor beta gene in T-cell lymphomas.

The expression of T-cell receptors (TCR) in malignant lymphomas was examined immunohistochemically by monoclonal antibodies which react with the TCR beta or TCR delta chain. TCR beta was expressed in 16 out of 47 non-Hodgkin's lymphomas. These included 15 T-cell lymphomas and 1 Ki-1 lymphoma. The anti-TCR beta chain antibody, beta F1, did not react with 26 B-cell lymphomas, 1 Ki-1 lymphoma or 6 Hodgkin's disease. This anti-TCR delta chain antibody, TCR delta 1, did not react with any type of malignant lymphoma. Although TCR beta and CD3 were co-expressed in normal lymphoid tissues and most T-cell lymphomas, 3 cases of CD3+ CD4+ CD8- T-cell lymphoma failed to express TCR beta. TCR beta and Ig JH gene configurations in malignant lymphomas were examined by Southern hybridization. Although each of 9 T-cell lymphomas had a rearranged TCR beta locus, TCR beta gene rearrangement in the 3 cases of beta F1- CD3+ T-cell lymphomas was demonstrated by Southern blot. No transcripts of the TCR beta gene could be found in 2 out of the 3 beta F1- CD3+ T-cell lymphomas by Northern blot, indicating the lack of TCR beta protein expression to be due to non-transcription of the TCR gene. Loss of TCR beta proteins in these T-cell lymphomas is thus quite likely to be associated with T-cell tumour activation and progression, since 3 beta F1- CD3+ T-cell lymphomas expressed CD25 (interleukin-2 receptor) to a high degree.