Sub-Populations Of Human Lymphocytes-T - .15. Lymphocytes-T With Receptors For Iga (T Alpha), A Distinct Sub-Population Of Lymphocytes-T - Studies In Patients With Primary Immunodeficiency Disorders

A receptor for IgA was observed on a subset of T cells (T alpha) that is distinct from other T lymphocyte subsets, T mu or T gamma cells. IgA receptor on T alpha cells is blocked by IgA from human serum through its cytophilic attachment. Neither T mu nor T gamma cells, following an in vitro interaction with insoluble immune complexes during the process of purification and further incubation at 37 degrees C, changed their phenotypes to T alpha cells. However, some T gamma cells demonstrated transition to T mu cells. The numbers and proportion of T alpha cells in patients with selective IgA deficiency were either normal, increased or decreased. The significance of T alpha cell analysis in thirty-one patients with primary immunodeficiency disorders including those with selective IgA deficiency is discussed.