Transcription of unrearranged t cell receptor ∂ genes in cd3‐ major histocompatibility complex‐unrestricted cytotoxic cells

Transcription of the T cell receptor (TcR) delta gene was detected in clones and in enriched populations of CD3- major histocompatibility complex-unrestricted cytotoxic cells. The transcripts were derived, at least in part, from unrearranged TcR delta genes, as shown by hybridization to a synthetic oligonucleotide probe corresponding to germ-line sequences just upstream of J delta 1. Transcripts from unrearranged TcR delta genes are similar in size to those from productively rearranged genes. The fact that the bulk of delta transcripts was derived from unrearranged genes was supported by the observation that TcR delta gene rearrangements were not detected in DNA isolated from an enriched CD3- cytotoxic cell population. Transcription of the TcR delta gene in CD3- cytotoxic cells is consistent with the notion that these cells belong to a T cell lineage.