title: T cell receptor genes do not rearrange or express functional transcripts in natural killer cells of scid mice.
abstract: The lineage of natural killer (NK) cells is poorly understood. To examine the relationship between NK cells and cells of the T lineage we have examined purified NK cells from a mutant mouse strain (scid) with severe combined immunodeficiency. Approximately 40% of the lymphoid cells in the spleens of scid mice expressed the NK-specific marker NK-2.1. All NK activity of the scid spleen cells could be accounted for by the NK-2.1+ population, similar to results obtained by using normal C57BL/6 X DBA/2 (B6D2F1) mice. Sorted NK-2.1+ cells proliferated in response to human recombinant interleukin 2 (r-IL 2) but not to concanavalin A (Con A), and were maintained in culture for 2 to 3 wk. Cultured NK-2.1+ cells displayed a cell surface phenotype (Asialo-GM1+, Thy-1.2+, L3T4-, Lyt-2-) and lytic activity similar to that described for freshly isolated NK cells of normal mice. Furthermore, T cell receptor (TCR) genes of the TCR-gamma and TCR-beta loci were in germline configuration, and no functional transcripts of TCR-gamma, TCR-beta, or TCR-alpha were detected. We propose that the expression of the TCR is not necessary for functional NK activity, and NK cells are distinct from both mature cytotoxic T lymphocytes and the earliest identifiable T cells.
mesh_terms: D000818:Animals; D000954:Antigens, Surface / Q000032:analysis; D002469:Cell Separation; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D005796:Genes; D007113:Immunity, Innate; D007153:Immunologic Deficiency Syndromes / Q000235:genetics*; D007694:Killer Cells, Natural / Q000502:physiology*; D051379:Mice; D008817:Mice, Mutant Strains; D011948:Receptors, Antigen, T-Cell / Q000235:genetics*; D011995:Recombination, Genetic; D014158:Transcription, Genetic
chemical_list: D000954:Antigens, Surface; D011948:Receptors, Antigen, T-Cell