ABSTRACT
Blood neutrophils and their bone marrow cell progenitors have membrane receptors for C3 and for the Fc portion of IgG. To test possible changes in the expression of those receptors associated to diseases we studied: a) blood of 31 and bone marrow of 9 normal individuals; b) blasts of 29 patients with acute myeloblastic leukemia; c) bone marrow of 8 patients with severe bacterial infections. The receptors were evaluated by rosette techniques: Saccharomyces C3 and sheep erythrocyte specific IgG antibody. Dried droplet stained smears were used to count rosettes of cells at different stages of maturation. The studies disclosed the following: a) these receptors are detected in progressively increasing percentage of cells throughout the differentiation steps of the granulocytic series; receptor for C3 is depicted as starting in promyelocytes, and receptor for Fc in myelocytes; the percentage of bone marrow neutrophils expressing these receptors is lower than that of blood neutrophils; b) in acute myeloblastic leukemia, blasts frequently express receptors normally found at more mature levels of differentiation which is an expression of nucleocytoplasmic asynchronism; there is good correlation between the FAB classification and the expression of these receptors; c) in severe bacterial infections, the receptors are found at earlier stages and in a higher proportion of cells at early maturation steps, marking a shift to the left in the expression of receptors.
Subject(s)
Bacterial Infections/blood , Leukemia, Myeloid, Acute/blood , Receptors, Complement/immunology , Receptors, Fc/immunology , Bone Marrow Cells , Humans , Neutrophils/analysis , Receptors, Complement/analysis , Receptors, Fc/analysis , Stem Cells/analysisABSTRACT
Blood neutrophils and their bone marrow cell progenitors have membrane receptors for C3 and for the Fc portion of IgG. To test possible changes in the expression of those receptors associated to diseases we studied: a) blood of 31 and bone marrow of 9 normal individuals; b) blasts of 29 patients with acute myeloblastic leukemia; c) bone marrow of 8 patients with severe bacterial infections. The receptors were evaluated by rosette techniques: Saccharomyces C3 and sheep erythrocyte specific IgG antibody. Dried droplet stained smears were used to count rosettes of cells at different stages of maturation. The studies disclosed the following: a) these receptors are detected in progressively increasing percentage of cells throughout the differentiation steps of the granulocytic series; receptor for C3 is depicted as starting in promyelocytes, and receptor for Fc in myelocytes; the percentage of bone marrow neutrophils expressing these receptors is lower than that of blood neutrophils; b) in acute myeloblastic leukemia, blasts frequently express receptors normally found at more mature levels of differentiation which is an expression of nucleocytoplasmic asynchronism; there is good correlation between the FAB classification and the expression of these receptors; c) in severe bacterial infections, the receptors are found at earlier stages and in a higher proportion of cells at early maturation steps, marking a shift to the left in the expression of receptors.
