Double-faced cell-mediated immunity in beta-thalassemia major: stimulated phenotype versus suppressed activity.
In this study, the immunologic abnormalities of Iranian beta-thalassemia major patients were characterized, considering their clinical parameters including splenectomy status and iron overload. Serum samples and peripheral blood mononuclear cells were collected from 28 patients and 30 age- and sex-matched healthy individuals. Patients with thalassemia showed significantly increased absolute lymphocyte counts compared with the control group. An increased number of activated T cells and higher levels of serum neopterin were also observed in thalassemia patients, which suggest chronic stimulation of immune system. On the contrary, T-cell proliferation and interleukin 2 (IL-2), interferon gamma (IFN-gamma), and IL-4 production were suppressed in patients compared to controls. Patients with high serum ferritin levels produced significantly less IFN-gamma and IL-2, indicating the immunosuppressive effect of iron overload in beta-thalassemia patients. The serum levels of tumor necrosis factor alpha and absolute counts and percentages of B and T cells were higher in splenectomized patients; however, serum levels of neopterin significantly decreased in splenectomized patients compared to the non-splenectomized group. Taken together, T lymphocytes express activated phenotype in polytransfused beta-thalassemia major patients, while T cell proliferation and effector function are significantly suppressed. Multiple blood transfusion and continuous immune stimulation could be responsible for making such a double-faced immune response.
Gharagozloo
Marjan
M
Immunology Department, Medical School, Shiraz University of Medical Science, 71345-1798 Shiraz, Iran.
Karimi
Mehran
M
Amirghofran
Zahra
Z
D000293:Adolescent; D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology; D016207:Cytokines / Q000097:blood / Q000276:immunology; D005260:Female; D006801:Humans; D007111:Immunity, Cellular / Q000276:immunology*; D007492:Iran; D019190:Iron Overload / Q000276:immunology; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D019798:Neopterin / Q000097:blood / Q000276:immunology; D010641:Phenotype; D013156:Splenectomy; D013601:T-Lymphocytes / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D055815:Young Adult; D017086:beta-Thalassemia / Q000097:blood* / Q000276:immunology* / Q000601:surgery
D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D019798:Neopterin