Abstract

The serum concentrations of the phagocytosis-stimulating peptide, tuftsin, were determined by radioimmunoassay in 21 patients with sickle cell disease and in 12 healthy controls. The mean serum tuftsin concentration was significantly lower in patient with haemoglobin SS disease (154.3 +/- 35.1 ng/ml; 308.6 +/- 70.2 nmol/l, P < 0.01) and in patients with haemoglobin SC and CC disease (180.9 +/- 42.7 ng/ml; 361.8 +/- 85.4 nmol/l, P < 0.05) than in healthy controls (228.7 +/- 46.7 ng/ml; 457.4 +/- 93.4 nmol/1). Tuftsin deficiency is an indicator of splenic hypofunction and may contribute to the increased susceptibility of patients with sickle cell disease to severe infection.