title: Lymphocyte subpopulations in Down's syndrome: high percentage of circulating HNK-1+, Leu 2a+ cells.
abstract: Peripheral blood lymphomononuclear cells (PBL) from 35 patients with Down's syndrome (DS, trisomy-21; 25 institutionalized and 10 non-institutionalized) were phenotypically characterized by means of various monoclonal antibodies. They included a high percentage of T lymphocytes with low avidity for sheep erythrocytes as well as an extremely high percentage of HNK-1+ cells and of lymphocytes reacting with the OKT8 and Leu 2a antibodies. The HNK-1+ cells of DS include four different subsets: (a) E+, OKT3+, OKT8-, Leu 2a-; (b) E+, OKT3+, OKT8+, Leu 2a+; (c) E-, OKT3-, OKT8-, Leu 2a- and (d) E-, OKT3-, OKT8+, Leu 2a+. Subsets (a) and (c) are also present in PBL from karyotypically normal controls while subsets (b) and (d) have a phenotype which has not been previously reported. These findings may be related to the triple expression by trisomic cells of the receptor for interferon, which is coded by a gene located on chromosome number 21. Alternatively, the high number of 'immature' NK cells of DS, possibly identical with pre-T lymphocytes, may originate from the congenital thymic derangement associated with trisomy 21.
mesh_terms: D000293:Adolescent; D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D004314:Down Syndrome / Q000097:blood* / Q000276:immunology; D005260:Female; D006801:Humans; D007223:Infant; D007694:Killer Cells, Natural / Q000276:immunology; D008214:Lymphocytes / Q000145:classification* / Q000276:immunology; D008297:Male; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface