T-cell chronic lymphocytic leukemia. T-cell function and lymphokine secretion.
The leukemic T-cells of the six patients with T-cell chronic lymphocytic leukemia (T-CLL), four with CD4 and CD45R-positive (CD4+ CD45R*) T-CLL and two with CD8 and CD45R-positive (CD8+ CD45R+) T-CLL phenotype were studied for detailed immunologic phenotypic and functional characteristics. The levels of soluble interleukin-2 receptors were elevated significantly in the serum of all four patients with CD4+ CD45R+ T-CLL. Moreover, the CD4+ CD45R+ T-CLL patients' T-cells, after in vitro stimulation with phytohemagglutinin and concanavalin A, expressed elevated percentages of interleukin-2 receptors on cells and secreted high interleukin-2 activity. The B-cell growth factor (BCGF) activity from three patients with CD4+ CD45R+ T-CLL was enhanced, but B-cell differentiation factor (BCDF) activity of the all T-CLL patients was decreased. Reduced BCGF and BCDF activity of the leukemic T-cells was one possible mechanism of hypogammaglobulinemia detected in two patients with T-CLL. All T-CLL patients' leukemic T-cells had diminished immunoregulatory functional activity in allogeneic mixed lymphocyte reactions. These observations suggest that leukemic T-cells from T-CLL patients have many immunologic functional defects that may be important in their proliferative potential.
Raziuddin
S
S
Department of Clinical Immunology, King Saud University, College of Medicine, Abha, Saudi Arabia.
Sheikha
A
A
Latif
A A
AA
D000368:Aged; D000369:Aged, 80 and over; D015703:Antigens, CD / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology; D015461:Leukemia, Prolymphocytic, T-Cell / Q000276:immunology*; D008222:Lymphokines / Q000378:metabolism*; D008875:Middle Aged; D010641:Phenotype; D015375:Receptors, Interleukin-2 / Q000032:analysis; D013601:T-Lymphocytes / Q000276:immunology*
D015703:Antigens, CD; D000954:Antigens, Surface; D007376:Interleukin-2; D008222:Lymphokines; D015375:Receptors, Interleukin-2; D015847:Interleukin-4