Specific features of metal-catalyzed oxidation (MCO) of purified proteins (human serum albumin and human erythrocyte superoxide dismutase) were analyzed by the oxidation level of tryptophan and tyrosine. The production of dityrosine cross-links and the oxidation of tryptophan residues were recorded by fluorescence. The degree of oxidative modification of the amino acid residues of the proteins depended on the concentration of the Fenton's medium components and on the incubation time. These changes were different in different proteins. By electrophoresis and gel-permeation chromatography, changes in the superoxide dismutase structure are shown to be caused by oxidative modification of the enzyme and to be accompanied by a decrease in its activity. Findings with OH* scavengers (mannitol and ethanol) suggest that oxidative modification of the proteins in Fenton's medium should be associated not only with hydroxyl radical but also with ferryl and perferryl ions and with the radical CO(-.)(3).

Background. Determination of Rh-affiliation is mandatory for donors and recipients, surgical patients, pregnant women, etc. There are variants of the D antigen that are difficult to identify by serological methods, for example, a weak D antigen. Aim. Determination of Rh-affiliation using genotyping in difficult cases, when the use of serological methods does not allow obtaining a reliable result. Material and methods. We studied blood samples from donors (n=18), pregnant women (n=17) and patients with hematological diseases (n=15): 22 men and 28 women, median age 36 years (25 to 54 years). Serologically, antigen D was determined by gel technology in ID-cards and in an indirect antiglobulin test with anti-D-IgG reagent. Weak D antigen variants were diagnosed and phenotype determined using polymerase chain reaction with allele-specific primers. For significance of differences in the frequency of types of weak antigen D, a nonparametric statistical method using a two-tailed Fisher's exact test was used. Differences were considered statistically significant at p 0.05. Results. The use of genotyping made it possible to detect the presence of a weak antigen D in 41 samples. Its specificity was represented by the following types: 1; 1.1; 2; 3. Other types of weak antigen D [4; 4.0; 4.1; 4.2 (DAR); 5; 11; 14; 15; 17] were absent. The study of the phenotype of erythrocyte antigens of the Rhesus system using genotyping revealed the predominance of the Ccee phenotype in people with a weak D antigen. Significant differences in the frequency of types of this antigen were revealed. Conclusion. The use of molecular genetic typing made it possible to determine the types of the weak antigen D and to accurately determine the Rh-affiliation of the subjects.

Aim. To assess the possibility of using blood group genotyping in recipients who received transfusions for 3 months. Methods. The study included blood samples from 95 patients who received 3 or more erythrocyte transfusions within 3 months. The patients had the following diagnoses: multiple myeloma (n=7), beta thalassemia (n=4), non-Hodgkin's lymphomas (n=11), chronic myeloid leukemia (n=16), primary myelofibrosis (n=9), myelodysplastic syndrome (n=22), acute leukemia (n=21), aplastic anemia (n=5). Red blood cells phenotyping was performed in Diaclon Rh Subgroups+K Gel Cards. The Rh and Kell genotyping was performed by using RBC SSP-PCR kits FluoGene vERYfy (Inno-train Diagnostics, Germany). The standard RHD/RHCE alleles, as well as polymorphisms associated with KEL1/KEL2 [T698C (Met198Thr)] of the KEL gene were genotyped. Results. The concordance rate between serological and molecular genetic typing of RhCE and Kell blood groups for donors was 100%, while the patients results were discordant in 45.3% of cases. Discrepancies in antigens of the Rh system were registered in 41 patients: one antigen of the Rh system in 30 patients, two in 9 patients. Ten patients who had been previously phenotyped as RhCc were genotyped as RHCE*CC. 2 patients who had been previously phenotyped as Rhee were genotyped as RHCE*EE. In 2 patients, antigens D and C were not detected in the phenotype but were identified in the genotype. Discrepancies in antigen K were recorded in 2 patients, and the antigen was absent in the phenotype but was present in the genotype. The genotyping results were confirmed by serological typing at subsequent hospitalizations. Сonclusion. Blood group genotyping is a useful adjunct to traditional methods when serological typing is limited.

Background.Screening for anti-erythrocyte alloantibodies is a mandatory pre-transfusion test. The correct interpretation of the screening results plays a key role in ensuring the immunological safety of hemotransfusion therapy. Aim. To study the features of anti-erythrocyte antibodies detection in patients with hematological diseases. Material and methods. The study was performed with blood samples of 1269 patients with hematological diseases (569 male and 700 female patients aged 1885 with a median of 63 years). Screening and identification were carried out in indirect antiglobulin test using ID Coombs Anti-IgG gel cards with 4 and 15 samples of test erythrocytes as well as the salt agglutination method. The results were evaluated visually. The Pearson chi-squared test was used to check the statistical significance of differences in the alloimmune anti-erythrocyte antibodies frequency detection. The differences were considered statistically significant at p 0.05. Results. Interpretation of the anti-erythrocyte alloantibodies screening results was difficult in 6.55% of cases and was associated with the presence of autoantibodies in plasma (0.6%) and cross-reactive antibodies (5.9%). Аnti-erythrocyte alloantibodies were detected in 2.05% of cases which required further identification of antibody specificity. Antibodies to Rh system antigens were detected in 68.2% of cases, to antigens of other erythrocyte systems in 31.8% of cases. In Rh-negative patients only anti-D or anti-DC antibodies were detected. Rh-positive patients were more likely to have anti-K antibodies (30%). Anti-E antibodies were discovered in 20% of cases, anti-Cw and anti-Fya in 10% each. Alloantibodies were detected most frequently in patients with -thalassemia (20%), aplastic anemia (13%), hemophilia (9.2%) and thrombophilia (6.9%) and less frequently in patients with hemoblastosis and hematopoiesis depression (0.32.4%). Cross-reacting antibodies were detected more frequently in patients with multiple myeloma (74.7%; p 0.05) than in patients with chronic lymphocytic leukemia (17.3%), myelodysplastic syndrome (5.3%), and acute leukemia (2.7%). Conclusion. The reasons for the difficulties in interpreting the alloantibody screening results in hematological patients were the presence of autoantibodies (0.6%), alloantibodies (2.05%) and cross-reacting antibodies (5.9%).