Defective adherence of polymorphonuclear leukocytes to nylon induced by thalassemic serum

The effects of sera obtained from 18 patients with homozygous beta-thalassemia on the adherence and chemotaxis of normal polymorphonuclear leukocytes (PMNLs) was studied. The adherence of PMNLs suspended in thalassemic serum was 3.1% +/- 2.5% (mean +/- SD) compared with 17.9% +/- 8.0% adherence in control serum (P less than 0.00001). Zymosan-treated thalassemic serum did not generate chemotactic factors, and zymosan-treated normal serum did not induce chemotaxis of PMNLs suspended in thalassemic serum. When added to zymosan-treated normal plasma, thalassemic serum inhibited augmentation of PMNL adherence to nylon columns. These abnormalities were due to a heat-labile factor(s) in the sera of patients with thalassemia. Suspending PMNLs in heated thalassemic serum (56 C for 30 min) resulted in an increase of adherence to 14.6% +/- 6.2% (P less than 0.0001). PMNLs suspended in heated thalassemic serum responded normally to chemotactic attractants.