Humoral immune abnormalities in T-cell large granular lymphocyte leukemia

The prevalence of humoral immune dysfunction has not been defined in a large series of patients with T-cell large granular lymphocyte leukemia (T-LGL) confirmed to be clonal by T-cell receptor analysis. Therefore we evaluated the presence of multiple autoantibodies in 27 patients with this disease. Humoral immune abnormalities included: rheumatoid factor (RF) (15/27 patients), antinuclear antibody (ANA) (13/27 patients), polyclonal hypergammaglobulinemia (15/24 patients), elevated serum immunoglobulins (17/26 patients), immune complex formation (18/25 patients), elevated beta-2 microglobulin (13/18 patients) and neutrophil-reactive IgG (18/20 patients). Disease manifestations in these patients were due to complications of cytopenia or autoimmune abnormalities. Infection was a common finding (21/27 patients) and likely reflected their neutropenia. Rheumatoid arthritis (11/27 patients), anemia (12/27 patients) and thrombocytopenia (10/27 patients) were less common but still frequently observed. This study demonstrates the presence of multiple autoantibodies in a large series of patients with documented clonal T-LGL proliferations.