Further analysis of the T cell receptor gamma/delta+ peripheral lymphocyte subset. The V delta 1 gene segment is expressed with either C alpha or C delta.

Abstract

In the present study, we have characterized the reactivity of two mAbs that are directed at the human TCR-gamma/delta. These reagents, designated anti-A13 and anti-TiV delta 2, were found to recognize antigenic determinants encoded by the TCR V delta 1 and V delta 2 gene segments, respectively. Immunofluorescence analyses performed with the antibodies confirmed that, in the TCR-gamma/delta+ cell subpopulation, the expression of V delta 2+ delta chains is largely predominant, as compared with the V delta 1+ counterparts. However, these experiments led to an apparently discrepant finding. Indeed, the total number of cells recognized by the anti-A13 plus the anti-TiV delta 2 antibodies was often greater than that detected with anti-TCR-delta 1, a reagent specific for a constant epitope of the human delta chain. Further investigation showed that the presence of a sizeable peripheral lymphocyte subset coexpressing the BMA031 and the A13 epitopes. Because the former antibody is known to recognize an invariant antigenic determinant of the TCR-alpha/beta dimer, these results suggested that the V delta 1 gene segment may be expressed with either C delta or C alpha. This hypothesis was confirmed using T2, an IL-2-dependent BMA031+ A13+ polyclonal cell line developed from peripheral blood of a healthy adult donor. Indeed, T2 cells were found to have productively rearranged the V delta 1 gene. Together, results of Northern blot analysis and cDNA cloning indicated that V delta 1 was expressed in these cells as part of a 1.6-kb full-length message including J alpha-C alpha segments.

HLA class I‐restricted recognition of an HIV‐derived epitope peptide by a human T cell receptor α chain having a Vδ1 variable segment

“…2). This result confirmed the previous findings by Miossec et al [6,7] that a small subset ( X 0.5%) of human peripheral T cells expressed Vˇ1-encoded variable segments on § g T cells. Using a C gspecific antisense primer, we isolated TCR-g cDNA containing a V g 13.3-encoded gene segment (Table 1), suggesting that the Vˇ1.1-bearing TCR- § chain was paired with TCR-g chain on the surface of CTL 55.…”

“…3). In addition, mAb A13 [9], specific for an epitope encoded by Vˇ1 gene segments transcribed along with either J § C § or JˇCˇ [6] reacted with CTL 55 (Fig. 3A).…”

“…It has been reported, however, that some Vˇgenes are rearranged either to J § or to Jǧ enes and can therefore be used in the synthesis of TCR- § orˇchains, which are expressed in the § g and +Ť cells, respectively. For example, a subset of human peripheral T cells expressing Vˇ1 antigens on their surface were found in both § g and +ˇT cell lineages as revealed by multi-color flow cytometry [6]. Sequencing analysis of TCR genes revealed the existence of Vˇ1J § C § transcripts encoded by a unique Vˇ1J § rearrangement in the Vˇ1-expressing § g T cells [7].…”

Restriction of the T-cell receptor V delta gene repertoire is due to preferential rearrangement and is independent of antigen selection

“…Thick bars indicate two or three V genes sharing an identical similarity value. Asterisks correspond to V genes expressed or rearranged at both TCRD and TCRA loci but without a double nomenclature (for DV1, see Miossec et al 1990) Here we show that the same, small set of V genes is rearranged both in the productive and unproductive allele. Ten of the twelve V gene rearrangements found on the unproductive chromosome contained the four most common DVelements (DV1-3 and DVS), which were expressed on the surface of over 95% (77/80) of our TCRG/D clones.…”

Human T-cell receptor variable gene segment families

“…ADV segments, however, isolated using V segment-specific PCR primers, may be rare transcripts, expressed in (z[3 T cells in which the TCRD locus is not deleted on one allele (Genev6e et al 1994). It has been reported only for the DVIO1 gene segment that its product can be expressed on the surface of both the o~3 and 76 T-cell subpopulations (Miossec et al 1990). It has recently been shown that y8 Tcell clones express two novel DV gene segments, called V67 and V68, on the cell surface.…”