Association between Non-secretion of ABH Antigens and Sickle Cell Anaemia

Aim: To determine whether non-secretion of ABH blood group antigens was associated with Sickle Cell Anaemia. Materials and Methods: Haemaglutination inhibition test was carried out on saliva samples from 300 individuals; 100 of whom had haemoglobin (Hb) genotype AA, 100 HbAS, 50 HbAC and 50 HbSS. ABO blood grouping was carried out by standard methods and Haemoglobin genotype test was performed by cellulose acetate electrophoresis technique. Results: Eighteen percent (18%) of HbAA, 23% of HbAS, 18% of HbAC and 42% of HbSS individuals were non-secretors of ABH antigens (p = 0.007). Non-secretion of ABH substances was more associated with HbSS persons than HbAA (p = 0.002), HbAS (p = 0.016) and HbAC (p = 0.009) individuals. Conclusion: Non-secretion of ABH blood group substances is associated with Sickle Cell Anaemia.

Detection of O-glycosylated proteins from different Trichinella species muscle larvae total extracts

The aim of the work was to analyze oligosaccharide composition with the focus on O-linked glycoproteins presence in the total extract obtained from different Trichinella species muscle larvae by means of lectin affino-blot with lectins selected for their sugar specificity. The absence of reactivity with two lectins, Tritrichomonas mobilensis lectin and Maackia amurensis agglutinin, indicated that the species of the Trichinella genus do not synthesize sialic acid. Reactivity with Helix pomatia lectin, Vicia villosa lectin-B4, peanut agglutinin and Ulex europeus lectin-I identified the presence of O-linked glycans identical to carcinoma-associated Tn-antigen (GalNAc-α-Ser/Thr) and T-antigen (Gal-β1,3-GalNAc-α-Ser/Thr) and also structures analogous to ABH-blood group antigens. The results obtained may contribute to a better understanding of the glycobiology of this parasitic nematode in relation to occupation of its intracellular niches.

Fucosylated Thomsen-Friedenreich antigen in alpha-anomeric configuration in human gastric surface epithelia: an allogeneic carbohydrate antigen possibly controlled by the Se gene.

Human gastric surface epithelial cells display the ABH blood group antigens with the core structure of N-acetyllactosamine (NAcLc). Their expression is under the control of the secretor gene Se. The Thomsen-Friedenreich (T)-antigen (Gal beta 1-3GalNAc) is another core structure of the ABH antigens. We examined the gastric surface epithelial expression of T- and alpha 1-2 fucosylated T (FucT) histochemically with peanut agglutinin (PNA) and monoclonal antibody (MAb) MBr1, respectively. Eight of 24 individuals exhibited the PNA-reactive antigen (i.e., T-expressers) and others the MBr1-reactive antigen (i.e., FucT-expressers). alpha-L-fucosidase digestion of the FucT-positive tissues and beta-galactosidase digestion of the T-positive tissues, respectively, made them reactive with PNA and the antibody specific for GalNAc alpha-O-Ser/Thr. There was a remarkable correlation among reactivities with MBr1, Ulex europaeus lectin 1 (UEA1), and anti-Leb MAb CO-431. ABH blood group status had no correlation with this expression. We conclude that human gastric surface epithelial cells constitutionally synthesize T in alpha configuration (i.e., Gal beta 1-3GalNAc alpha-O-Ser/Thr) and that it was alpha 1-2 fucosylated only in the FucT-expressers. alpha 1-2 fucosylation of T is suggested to be regulated by the Se gene.