title: Impairment of the autologous mixed lymphocyte reaction in atopic dermatitis.
abstract: The T cell proliferative response to autologous non-T cells is termed the autologous mixed lymphocyte reaction (AMLR). Recent studies have suggested that the AMLR represents an inducer circuit for the activation of T8+ suppressor/cytotoxic effector cells. Since atopic dermatitis (AD) patients are deficient in T8+ cytolytic T cell function, we investigated the AMLR in AD. When sheep erythrocytes were used to separate T cells from non-T cells, the AMLR was found to be significantly decreased (P less than 0.001) in AD patients (n = 11; delta cpm = 1,550 +/- 393) when compared with normal control subjects (n = 13; delta cpm = 25,819 +/- 4,609). To exclude the possibility that these results were an artifact of the sheep erythrocyte separation, T cells were also separated on a fluorescence-activated cell sorter after treatment of peripheral blood lymphocytes with the OKT3 monoclonal antibody. AD T cells separated by the latter method were also found to have a significantly reduced AMLR response when compared with similarly treated normal T cells. Co-culture studies using cells from AD patients and their HLA identical siblings indicated that the defect resided at the responder T cell level rather than at the stimulator non-T cell level. Co-culture studies revealed no evidence for excessive suppressor cell activity resulting in the decreased AMLR. However, enumeration of T cells reactive with the monoclonal antibody T29, which recognizes a subset of T cells proliferating in the AMLR, demonstrated that AD patients (n = 8; % T29 = 2.5 +/- 0.7) had a significantly decreased (P less than 0.001) number of circulating T29+ T cells when compared with normal controls (n = 8; % T29 = 10.4 +/- 0.8). These studies suggest that a deficiency of T4+ T29+ cells contributes to the deficient AMLR in AD and possibly underlies the abnormalities of T8+ effector cells present in this disease.
mesh_terms: D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D003601:Cytotoxicity Tests, Immunologic; D003876:Dermatitis, Atopic / Q000235:genetics / Q000276:immunology*; D005260:Female; D006680:HLA Antigens / Q000032:analysis / Q000235:genetics; D006801:Humans; D007111:Immunity, Cellular; D007959:Lymphocyte Culture Test, Mixed; D008297:Male; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D006680:HLA Antigens