| Abstract: | Summary. Thirty-five Thai patients with various α-thalassaemia (α-thal 1/α-thal 2, α-thal 1/HbCS, HbCS/ HbCS) and yβ-thalassaemia (β-thal/HbE, severe and mild form, HbE/HbE) syndromes were examined for the presence of immunoglobulins and C3d on o-tolidine positive erythroblasts in the bone marrow, and for the amounts of IgG of some specificities bound to circulating erythrocytes. In mild, but not in severe yβ-thal/HbE and in α-thalassaemia, the percentages of Ig-positive erythroblasts were significantly higher than in controls and correlated well with the percentages of IgG-positive erythroblasts. By contrast, the percentages of IgM and C3d positive erythroblasts were low and similar in thalassaemic and control marrows. A substantial proportion of thalassaemic patients showed more erythrocyte-bound IgG than controls, but statistically significant elevations were seen only in severe β-thal/HbE. Within a particular syndrome erythrocyte-bound IgG was more abundant in splenectomized than non-splenectomized subjects. It showed specificity for spectrin in some β-thalassaemic patients and for band 3 protein in several individuals with α- or β-thalassaemia. The results suggest that IgG antibodies play a role in the haemolysis of thalassaemia and that they are likely to be involved in the ineffective erythropoiesis in at least some of the syndromes studied. |
