HUMAN-BLOOD L-LYMPHOCYTES IN PATIENTS WITH ACTIVE SYSTEMIC LUPUS-ERYTHEMATOSUS, RHEUMATOID-ARTHRITIS AND SCLERODERMA - COMPARISON WITH T-CELLS AND B-CELLS

Abstract

Human blood lymphocytes with high affinity Fc receptors for Ig[immunoglobulin]G will bind small aggregates of this Ig at 4.degree. C. These cells were named L lymphocytes because of membrane-labile IgG determinants. L cells possess a profile of surface markers and functional characteristics which differ from T [thymus derived] and B [bone marrow derived] cells. Immunofluorescence methods were employed to quantify L lymphocytes in subjects with connective tissue diseases and certain infections. These values were then compared with those for T and B cells. The mean values of L lymphocytes in groups of patients with systemic lupus erythematosus, rheumatoid arthritis and scleroderma ranged between 14 and 18%; values similar to normals. Groups with acute pneumonia and tuberculosis had significantly increased percentages of L lymphocytes. The absolute number of L cells was decreased in subjects with connective tissue diseases, as was the number of T and B cells. L lymphocytes in those with infections were not significantly decreased. Only L lymphocytes were depleted by immobilized antigen-antibody complexes, another characteristic which distinguishes them from T and B cells.