text: Circulating immune complexes in sickle cell anaemia.
  A polyethylene-glycol insoluble serum fraction was studied in patients with sickle cell anaemia during the steady state of the disease. The levels of C1q-precipitins were normal but increased amounts of proteins, IgM C3 and factor B were detected in this immune complex enriched serum fraction. These findings are a sign that circulating immune complexes can be detected even in the asymptomatic period of the disease.