Follow-up of antibodies against single-stranded DNA in patients with haematological malignancies.

Antibodies against single-stranded DNA (ssDNA) were followed by enzyme-linked immunosorbent assay in weekly serum samples of 39 patients with acute myeloid leukaemia (AML), 11 with acute lymphatic leukaemia (ALL) and 26 with other haematological malignancies. Their frequency and mean level during the entire follow-up were higher than in sera of healthy blood donors. Patients with AML had the highest levels and prevalence of anti-ssDNA antibodies, i.e. overall frequencies of IgG class antibodies in patients with AML, ALL and other haematological malignancies were 97%, 82% and 58%, respectively. Antibodies of IgM class were less frequently found. Prevalence and levels of anti-ssDNA antibodies were already at least as high in newly diagnosed malignancies as later during the course of the disease. Following bacterial septicaemias, these antibodies were significantly low. No consistent correlations between levels of anti-Candida antibodies formed in response to fungal infections or concentrations of serum immunoglobulins and anti-ssDNA antibodies were found.