Open AccessNatural autoantibodies may play a role in ineffective erythropoiesis during megaloblastic haemopoiesis
Author(s) -
WIENER E.,
WICKRAMASINGHE S. N.
Publication year - 1991
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1991.tb05600.x
Subject(s) - haematopoiesis , biology , immunology , antibody , autoantibody , erythropoiesis , complement receptor , complement system , immune system , monoclonal antibody , receptor , stem cell , medicine , anemia , biochemistry , genetics
SUMMARY Marrow aspirates from 11 patients with megaloblastic haemopoiesis and from 14 healthy individuals with normoblustic haemopoiesis were studied for antibodies associated with polychromatic/orthochromatic erythroblasts, using an 125 I‐labelled anti‐human immunoglobulin reagent and autoradiography. In addition, the expression on these cells of receptors for FcIgG (FcR) and of the type I receptor for fragments of the third complement component (CR1) were investigated with receptor‐specific monoclonal antibodies. 125 I‐labelled anti‐mouse immunoglobulin and autoradiography. The percentages of immunoglobulin‐positive erythroblasts were significantly greater in the megaloblastic than in the normoblastic marrows. Abnormally high percentages of labelled erythroblasts were present in patients without any manifestations of an autoimmune disorder. The percentage of labelled erythroblasts in the marrows of the patients correlated well with the degree of anaemia. FcR were absent on the majority of megaloblasts or normoblasts while the expression of CRI was similar in both types of cell. The difference between the percentage labelling of megaloblasts and normoblasts was therefore unlikely to be due to greater binding of immune complexes with or without associated complement to mcgaloblasts than normoblasts. The megaloblast‐hound immunoglobulin is, therefore, likely to have recognized abnormally expressed epitopes on the surface of megaloblasts. The results suggest that natural autoantibodies play a role in the destruction of erythroblasts during megaloblastic haemopoiesis.