Autoantibody occurrence in hairy cell leukemia

Autoimmune syndromes accompanying hairy cell leukemia (HCL) may represent a specific entity in HCL patients. It has been claimed that interferon (IFN)-alpha therapy contributes to the occurrence of autoantibodies in HCL. The study was undertaken to determine the occurrence of autoantibodies in HCL patients prior to IFN-alpha therapy.

Sera of 24 patients with HCL of B-cell origin (as determined previously by peripheral blood mononuclear cell surface markers and/or DNA rearrangement studies) were investigated. In addition serum from a T-HCL patient was studied. Nineteen of the 25 HCL patients had been splenectomized prior to the study. One patient was found to have IgM lambda monoclonal protein in her serum. Antinuclear antibodies were determined with an indirect IF test using Hep-2 cells. Rheumatoid factors of the IgM and IgA classes were determined by enzyme-linked immunosorbent assay (ELISA). Granulocyte-specific antinuclear antibodies and antineutrophil cytoplasmic antibodies were determined by indirect immunofluorescence.

No clinical syndrome of an autoimmune disease was apparent in any of our HCL-patients. Rheumatoid factors of either IgM or IgA class were found in the sera of six B-HCL patients and antinuclear antibodies in five cases, while anti-cytoplasmic antibodies were identified in only three cases. The occurrence of antibodies seemed to be independent of the clinical stage of the disease as determined according to the functional criteria. Two patients with arthralgias and one with vitiligo had no autoantibodies in their sera.

Autoantibodies might occur in HCL patients prior to treatment with interferon-alpha and in the absence of the clinical syndrome of an autoimmune disease.