Rearrangement and organization of T cell receptor gamma chain genes in human leukemic T cell lines.

ABSTRACT

Seventeen T cell leukemic lines, which are arrested at different stages of differentiation, were analyzed for gamma-chain rearrangement and expression using the constant region gene and representatives of the different families of V gamma chain genes. With the exception of the T cell line P30/OKUBO, which is arrested at the earliest stage (stage I), all the leukemic lines have rearranged their gamma-chain genes and transcripts can be detected in all but MOLT-4 and P30/OKUBO cell lines. Although V gamma 1 genes were rearranged and expressed in leukemic lines arrested at stages II, III and IV, V gamma 2 and V gamma 3 were only rearranged and expressed in cells at stage III (0/5 in stage II, 5/9 in stage III and 0/1 in stage 4). Thus, there may be a sequential usage of V gamma gene during human T cell ontogeny (although it is possible that this may just be a coincidence), similar to that which has been shown during murine ontogeny. Based on the rearrangement data, the genomic order of 5' V gamma 1-V gamma 2-V gamma 3-J-C 3' is proposed.