Analysis of erythrocyte and platelet membrane proteins in various forms of beta-thalassemia.

Major membrane proteins have been quantitatively analyzed in erythrocytes and platelets from patients with homozygous (splenectomized and non-splenectomized) and heterozygous forms of beta-thalassemia depending on severity of clinical manifestation of this disease. Quantitative analysis of erythrocyte membrane proteins revealed increase in alpha- and beta-spectrin. (In non-splenectomized patients with homozygous beta-thalassemia the amount of this protein was lower than in corresponding controls.) Besides spectrin, the increase of 2.1-2.3 fractions of ankyrin, and the decrease of band 3 protein (anion-transport protein), 4.1, palladin, and glyceraldehyde-3-phosphate dehydrogenase were also found. Analysis of major platelet membrane proteins revealed significant increase in gelsolin. This increase was found in all forms of beta-thalassemia irrespective of gender. Significant changes in platelet membrane protein fractions were found in patients (especially non-splenectomized) with homozygous beta-thalassemia. These included significant decrease in myosin, profilin, and gamma-actin and increase in actin-binding protein in both male and female patients. The content of other protein fractions (alpha-actinin, tubulin, tropomyosin) remained unchanged. Changes in protein fractions of erythrocytes and platelets correlated with severity of clinical manifestation of the disease.

[Methemoglobin level and its comparison with levels of globins and membrane proteins in erythrocytes of patients with beta-thalassemia]. / Soderzhanie metgemoglobina i ego sravnenie s kolichestvom globinovykh i membrannykh belkov éritrotsitov u bol'nykh s beta-talassemiiami.

On the basis of conducted biological-and-chemical research, the clinical-and-genetic forms of beta-thalassemia were revealed, as well as fractions and the quantity of globin chains and membrane proteins were defined. The methods of electrophoresis and of isoelectrofocusing were made use of within the case study to separate between the globin chains and the membrane proteins. Samples of venous blood obtained from one hundred and one children with beta-thalassemia and from 45 donors were tested. Higher and lower values for different globin chains were found in investigating the quantitative ratios of various globin chains in patients with beta+, beta 0- and heterozygote variations of beta-thalassemia. Reliable changes in the quantitative content of main membrane proteins were observed in patients with heterozygote beta-thalassemia. The final study data denote that an excessive accumulation of alpha-globin chains in heterozygote beta-thalassemia is accompanied by a higher level of methemoglobin and by changed quantities of globin chains and membrane proteins.