Structural similarity between Fc receptors and T cell receptors. Expression of the gamma-subunit of Fc epsilon RI in human T cells, natural killer cells and thymocytes.
The TCR complex is composed of a clonotypic heterodimer (Ti alpha:beta or gamma:delta) noncovalently associated with the CD3 complex (gamma, delta, and epsilon), and with one or more disulfide-linked dimers whose components are designated zeta and eta. zeta and eta are alternative transcripts of a common gene and are structurally related to the gamma-subunit of the FcR for IgE expressed on mast cells and basophils (Fc epsilon RI). Recent evidence suggests that gamma can also be expressed in natural killer cells and in a murine cytotoxic T cell line, CTLL. Because zeta, eta, and gamma have the potential to join together to form disulfide linked homo- and heterodimers, it has been postulated that alternative dimeric forms composed of these zeta-related subunits might subserve unique signal transducing functions in hematopoietic cells. We have used mAb reactive with zeta and gamma to systematically examine the expression of these zeta-related dimers in human T cells, NK cells, and thymocytes. Our results show that each cell type expresses characteristic combinations of zeta-related homo- and hetero-dimers, and are therefore consistent with the possibility that these subunits contribute to the functional heterogeneity of lymphocyte subsets.
Vivier
E
E
Division of Tumor Immunology, Dana-Farber Cancer Institute, Boston, MA 02115.
Rochet
N
N
Kochan
J P
JP
Presky
D H
DH
Schlossman
S F
SF
Anderson
P
P
D000911:Antibodies, Monoclonal / Q000276:immunology; D000943:Antigens, Differentiation / Q000032:analysis; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis* / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D017252:CD3 Complex; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology*; D010766:Phosphorylation; D011948:Receptors, Antigen, T-Cell / Q000032:analysis*; D011961:Receptors, Fc / Q000032:analysis* / Q000276:immunology; D017455:Receptors, IgE; D017452:Receptors, IgG; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000944:Antigens, Differentiation, B-Lymphocyte; D000945:Antigens, Differentiation, T-Lymphocyte; D017252:CD3 Complex; D011948:Receptors, Antigen, T-Cell; D011961:Receptors, Fc; D017455:Receptors, IgE; D017452:Receptors, IgG