Altered erythrocyte membrane band 3 profile as a marker in patients at risk for cardiovascular disease.

The aim of this study is to evaluate the correlation between a rise in blood neutrophil concentration and cellular and molecular changes of erythrocytes, among populations presenting an increased risk of cardiovascular disease (CVD). A population of men aged 20-65 years was used which included 22 post-myocardial infarction individuals (< 48 h), 24 survivors of myocardial infarction (> 3 months), 12 hypertensive individuals and 29 individuals presenting normal haematological values and normal lipid profile. The lipid profile parameters used to ascertain increased risk of CVD included triglycerides (TG), total cholesterol (Chol), high-density lipoprotein cholesterol (HDLc), low-density lipoproteins cholesterol (LDLc) and apolipoproteins A1 (Apo A1) and B (Apo B). The hematological parameters measured were concentration of total white blood cells (WBC) and of the several leukocyte types; concentration of red blood cells (RBC); hematocrit (Ht); hemoglobin concentration (Hb); mean cell volume (MCV); activity of erythrocyte glucose-6-phosphate dehydrogenase (G6PD); band 3, its aggregates and fragments in erythrocyte membranes, the percentage of membrane-bound hemoglobin (MBH), and the linkage of immunoglobulin G (IgG) to erythrocyte membrane. We found that the MBH and the band 3 profile is different in control as compared to pathological groups and that, as expected, the aggregation of band 3 promotes the linkage of IgG to the erythrocyte membrane. A negative correlation was shown between total neutrophils and both total RBCs and erythrocyte G6PD activity. We suggest that the erythrocyte, a cell that undergoes and accumulates oxidative and proteolytic damage along its life span, may provide a useful model of oxidative and proteolytic stress in CVD and that band 3 may represent a useful marker of that stress.