Variability in T cell receptor V beta gene usage in human peripheral blood lymphocytes. Studies of identical twins, siblings, and insulin-dependent diabetes mellitus patients.

摘要: Recent studies focused on the diversity and molecular organization of human TCR-beta complex have begun to establish genetic basis for potential repertoire V beta specificities in T cells. The scope variability actual derived from this repertoire, however, remains be clarified. In study, usage by peripheral cells serial samples same individual, identical twins, members three nuclear families that include four with insulin-dependent diabetes mellitus (IDDM) was assessed both quantitative polymerase chain reaction Northern blotting subfamily-specific probes. Samples taken individual over a period 21 months analyzed separate experiments indicated stability whereas similarity pair twins suggested strong role genetics shaping cell repertoire. contrast, siblings unrelated individuals observed differ substantially. particular, expression 3 20 differed more than sixfold among two different families. Segregation analysis TCR HLA haplotypes these variation haplotype specific. Subsequent nucleotide sequence gene segment multiple revealed presence null allele expression. No consistent significant differences were IDDM patients relative their or between discordant IDDM. These results suggest present populations varies dramatically because effects factors, including germ-line polymorphism.