Immunodeficiency with low expression of the T cell receptor/CD3 complex. Effect on T lymphocyte activation.
We report the consequences of low expression of the T cell receptor (TcR)/CD3 complex by T lymphocytes from a 4-year-old boy with a mild immunodeficiency. TcR/CD3 expression was found to be deficient on both resting and activated T cells, using both anti-CD3 and anti-TcR alpha/beta monoclonal antibodies. As shown by immunofluorescence and immunoprecipitation studies, residual expression (corresponding to about 10% of normal) was detectable on resting and activated TcR alpha/beta+ T cells. Other T cell membrane receptors were normally expressed. The functional consequences of this TcR/CD3 expression deficiency included an absence of T cell proliferation, interleukin 2 receptor expression and calcium flux following anti-CD3 and anti-CD2 antibody-triggered T cell activation. Antigen (tetanus toxoid, Candida and allogeneic cell)-induced proliferation was detectable. In contrast, cytotoxic T cell activity towards allogeneic cells was deficient. These findings shed light on the function of the TcR/CD3 complex and indicate that the expression of a limited number of TcR/CD3 receptors may be sufficient to trigger antigen-specific T cell activation (and, possibly, differentiation) and that anti-CD3 antibody-induced T cell activation differs somewhat from antigen/major histocompatibility complex molecule-induced activation. These results also confirm that the CD2 pathway of T cell activation is CD3 dependent.
INSERUM U 132, Hôpital, Necker-Enfants Malades, Paris, France.
F
F
Le Deist
G
G
Thoenes
J
J
Corado
B
B
Lisowska-Grospierre
A
A
Fischer
D015703:Antigens, CD / Q000032:analysis*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis* / Q000502:physiology; D018801:CD2 Antigens; D017252:CD3 Complex; D002675:Child, Preschool; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D011948:Receptors, Antigen, T-Cell / Q000032:analysis* / Q000502:physiology; D011971:Receptors, Immunologic / Q000502:physiology; D013601:T-Lymphocytes / Q000276:immunology*
D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D018801:CD2 Antigens; D017252:CD3 Complex; D011948:Receptors, Antigen, T-Cell; D011971:Receptors, Immunologic