Phenotypic heterogeneity within the circulating human neonatal T4-positive T cell subset.
An indirect immunofluorescence staining technique was employed to evaluate the TQ1 and 5/9 monoclonal antibody lymphocyte reactivity in 10 cord blood mononuclear cell (MC) preparations enriched of E-rosette-forming cells (E+). Ten adult E+ MC populations were used as controls. Unfractionated T4+ cord and adult MC positively selected by panning procedure were also assayed. The results of these experiments, taken together, suggest that there is an overexpanded neonatal T cell subset which displays a previously unrecognized immunophenotype (T4+, TQ1+, 5/9+). Whether these lymphocytes are involved in the wellknown fetal-maternal immunosuppressive mechanisms of whether they are a further example of neonatal phenotypic immaturity remains to be elucidated.
D000328:Adult; D000911:Antibodies, Monoclonal / Q000276:immunology; D005312:Fetal Blood / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007231:Infant, Newborn / Q000097:blood / Q000276:immunology*; D008875:Middle Aged; D010641:Phenotype; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal