Objective: The aim of this work was to evaluate the expression of FUT2 gene in saliva and histo ABH antigens of patients with oral lesions.Study Design: In total 178 subjects were examined, half of whom suffered from oral pre-cancerous and cancerous lesions, while the other half were the healthy control group We analyzed the FUT 2 polymorphism by ASO-PCR (allele specific oligonucleotid - polymerase chain reaction) with specific primers for G428 allele and the wild type allele of FUT2 gene. To reveal A, B and H antigens in tissue sections of the patients (n=89) we used a modified specific red cell adherence technique.Results: We found a high intensity of oral disease in the non-secretor group (OR = 2.43). A total of 58% of the patients with oral pre-cancerous and cancerous lesions was non secretors (se_/_), in contrast with the healthy population (21.5%). A strongly positive reaction was defined as a sheet of indicator erythrocytes adhered to the epithelial cells. In 31 of the 54 samples analyzed the test showed slightly positive results on atypical areas, and there was a complete antigen deletion in areas affected by neoplasia. Nineteen samples showed a total absence of ABH antigens in both histologically normal and pathological areas. Blood group antigens were expressed at a high level in benign and highly differentiated malignant tumors. In poorly differentiated malignant tumors, they were mostly absent. Conclusion:Considering these results we suggest the use of this method to monitor probable preneoplastic lesions in risk population, especially in those with no secretor status (absence of FUT2 gene).

Although the pathogenesis of Autoimmune Hepatitis (AIH) is unknown, the susceptibility is determined in part by genes linked to the region of HLA class II. The study included 47 unrelated individuals with the diagnostic of type 1 AIH. A control group (n=81) of healthy individuals was included. The alleles were tested for HLA class II genotyping using polymerase chain reaction and sequence-specific primers technique (PCR-SSP). Among patients with AIH alleles occurring at higher frequencies were DRB1*04, DRB1*03, DRB1*01, DRB1*07 and DRB1*13. With reference to controls the following alleles were the most prevalent DRB1*07, DRB1*11, DRB1*08, DRB1*13 and DRB1*01. In comparison with the control group, AIH patients revealed a greater occurrence of the DRB1*03 and DRB1*04. These alleles can be considered as predisposing factors for the development of AIH. By contrast, DRB1*08 and DRB1*11 alleles were less frequent among patients and hence could be involved in disease resistance.

BACKGROUND:The serologic assignment of the RhD status may be hindered in patients with weak D expression. A comprehensive study of RHD alleles occurring in the mixed population of Argentina is necessary to evaluate the most suitable DNA typing strategy. STUDY DESIGN AND METHODS:A total of 18,379 patients from two stratified groups, Group 1 (G1; public hospital) and Group 2 (G2; private laboratory), were RhD phenotyped, and 88 samples with reduced D expression underwent molecular characterization. RESULTS:The frequencies of D+, D-, and variant D phenotypes differed significantly (p < 0.001) between G1 and G2 (94.49% vs. 87.66%, 5.15% vs. 11.58%, and 0.36% vs. 0.75%, respectively). Eleven alleles were responsible for the weak D expression. Approximately 60% of the variant D phenotypes from G1 and G2 were weak D Types 1 through 4.0/4.2 and 25% were DVII. RHD alleles associated with African ancestry were encountered in G1. A new -282G>A mutation within the promoter region of DAU-4 and DOL alleles was identified. Three weak D Type 1 samples on R(0) haplotypes were found in G1. CONCLUSIONS:The D phenotype distribution in G2 resembles that in Europeans while the frequencies in G1 account for the Amerindian and African genetic contribution. The genotyping strategy described here is suitable to study D variants in the overall population and could allow a better use of the few available D- units and a rational administration of anti-D immunoprophylaxis. The results also show that weak D Type 1 alleles do not exclusively segregate with a Ce allele, as assumed until present.

Objectives: To study membrane proteins modifications in Senescent Red Blood Cells (SeRBC).Design and methods: SeRBC were obtained on Percoll gradients. Membrane proteins were analyzed by SDS-PAGE, band 3 by immunoblotting, and protein oxidation by measuring the carbonyl groups.Results: Densitometric analysis showed no change in SeRBC while an increase in band 3 and its degradation products was found. An increase of protein oxidation level was found in SeRBC.Conclusions: These findings provide further experimental evidence about protein modifications occurring during the RBC lifespan. (C) 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

The Duffy (FY) blood group system is clinically significant in transfusion medicine because FY antibodies are involved in hemolytic transfusion reactions and hemolytic disease of the newborn. The Fya and Fyb antigens are encoded by the FY*A and FY*B alleles which are responsible for the Fy(a+b+), Fy(a+b−) and Fy(a−b+) phenotypes. The Fy(a−b−) phenotype is found in individuals homozygous for a silent FY*B allele, named FY*B ES , which is caused by a mutation in the promoter region of FY*B that result in the loss of FY expression in the erythroid linage. The aim of the present study was to evaluate the role of FY DNA typing as a tool in transfusion compatibility testing. We studied 275 white blood donors from the city of Rosario by serological method and allele specific PCRs. We found that the 106 serologically Fy(a+b+) samples all genotyped as FY*A/FY*B (100%). Among the 94 Fy(a+b−) samples, 81 (86.2%) were FY*A/FY*A and 13 (13.8%) were FY*A/FY*B ES . Of the 75 Fy(a−b+) 67 (89.3%) were FY*B/FY*B and 8 (10.7%) were FY*B/FY*B ES . No Fy(a−b−) samples were encountered. The frequencies of the FY*A, FY*B and FY*B ES alleles clearly revealed that the genetic pool analyzed is comprised of Caucasian and non-Caucasian alleles. These results showed that there is an important proportion of patients phenotyped as Fy(b−) that can be exposed to Fy(b+) blood units with no risk of alloimmunization when they carry the FY*A/FY*B ES genotype. Thus, FY genotyping allow increasing the pool of compatible units facilitating transfusion therapy and benefiting patients that require chronic transfusions.

Red blood cell (RBC) aging is a complex process affected by immunological and biochemical parameters. In this work we studied the antioxidant response in RBC of different ages. We also investigated their interaction with peripheral blood monocytes. Anticoagulated blood samples from 19 O RhD+ volunteers' donors were processed. Young (Y) RBC and Senescent (Se) RBC were obtained by self-formed gradients of Percoll. The fractionation of the erythrocytes suspensions was demonstrated by statistically significant density-related changes in hematological determinations. Activities of glucose-6-phosphate dehydrogenase (G6PD), of soluble NADH-cytochrome b5 reductase (b5Rs) and membrane-bound b5R (b5Rm) were determined spectrophotometrically. The interaction between monocytes and different RBC suspensions was evaluated by the erythrophagocytosis assay. The G6PD and b5Rm activities in SeRBC were significantly lower than that observed in YRBC. No differences were found in the b5Rs of both groups. We observed an increased rate of erythrophagocytosis the SeRBC compared to YRBC. The decline in the activities of G6PD and b5Rm would indicate a decrease in the antioxidant response associated to RBC aging. These findings would signify that the oxidative changes of membrane occurring during the life span of the RBC might be relevant in the process of removal of SeRBC from the circulation.

Chronic Chagas' disease occurs in a variable number of infected individuals and mainly manifests as an inflammatory cardiomyopathy that may lead to a fatal course. The factors underlying the establishment of chronic myocardial lesions are not fully understood. The study included 71 unrelated individuals serologically positive for T. cruzi. A group of 81 no related healthy individuals with neither symptoms nor previous diagnosis of Chagas' disease was studied as control group. Genomic DNA was extracted from peripheral blood using the standard salting out method and used as a template to amplify by the PCR the polymorphic second exon of the HLA-DRB1. PCR products were hybridized separately with sequence-specifics oligonucleotides (SSOP). DRB1*0409 and DRB1*1503 alleles were significantly more prevalent in seropositives (pC = 0.002, OR: 26.17 and 24.87 respectively). The prevalence of DRB1*1103 allele was statistically significant in the group control and could be associated with resistance Chagas' disease (pC = 0.026, OR: 0.19). Increased significance frequency of DRB1*1503 allele was found among cardiomyopathy patients suggesting that this antigen might be related with the genetic susceptibility to cardiac damage in these patients (pC = 0.014, OR: 9.22).

The mechanisms of aberrant expression of blood-group antigens are not clear in all cases. The aim of this work was to investigate Lewis blood type antigens and secretor status using biochemical and molecular biological methods in patients with oral lesions. We studied 148 subjects, half of whom suffered from oral lesions (benign, pre-cancerous and cancerous), while the other half were the healthy control group. We also investigated the Lewis phenotypes of fresh blood samples with a hemagglutination method. We analyzed polymorphisms of the FUT2 gene by ASOPCR (allele specific oligonucleotide– polymerase chain reaction) with specific primers for the G428 allele and the wild type allele of FUT2 gene. The FUT2 gene encodes the γ(1,2) fucosyltransferase (Se enzyme) that regulates expression of ABH antigens in the gastrointestinal tract and secretions. We found a higher intensity of oral disease in the non-secretor group (OR=3.44). Fifty one % of the patients with oral pre-cancerous and cancerous lesions were non-secretors (Le a+ b−), in contrast with the healthy population. We observed a marginal association between secretor status and these lesions.