Determination Of Blood Type Research Articles

Evaluation of the Gel System for ABO Typing of Monkeys

Monkeys do not express ABO antigens on red blood cells (RBCs), but on tissues, which is an obstacle in ABO typing. In this study we describe a simple and efficient method to type monkeys blood. Rhesus monkeys (n=34) and cynomolgus monkeys (n=16) were typed by the direct and reverse gel system, which has been widely used in clinics in recent years. Based on the results of immunohistochemical staining, we evaluated the feasibility and the interference factors of the gel system to type monkeys. The results revealed that the direct gel system didn’t have a positive report, the fibrinogen and non-specific anti-human antibodies in monkey blood interfered with the reverse gel system in some samples. In accordance with the results of immunohistochemical staining, using clear sera, which were pre-absorbed on normal human type O RBCs, the reverse gel system gave an accurate blood type determination for monkeys. We concluded that the reverse gel system could be used for ABO typing of monkeys, and the fibrinogen and non-specific anti-human antibodies were the major interference factors, which could be eliminated by using clear and pre-absorbed sera.

Buccal mucosal cell immunohistochemistry: a simple method of determining the ABH phenotype of baboons, monkeys, and pigs

Baboons and monkeys fail to express ABH antigens on red blood cells (RBCs), and the A or H antigens are expressed only weakly on the surface of pig RBCs. Baboons and monkeys have been previously blood typed by detection of ABH antigens in the saliva after administration of pilocarpine. A reliable method to ABH type pigs is by immunohistochemical staining of renal distal tubules in kidney biopsies. We describe a simple and efficient method to blood type baboons, monkeys, and pigs. Baboons (n = 14) and cynomolgus monkeys (n = 8) were blood typed by staining of buccal mucosal smears and by determining the presence of serum anti-A or B antibodies following human type O adsorption. Pigs (n = 11) were tested for ABH type by immunohistochemistry for the presence of A, B, and H antigens using monoclonal antibodies on (i) renal biopsies, (ii) RBCs, and (iii) buccal mucosal smears, without pilocarpine administration, in addition, (iv) after adsorption on human type O RBCs to remove anti-human antibodies, the pig sera were typed by hemagglutination assay for the presence of anti-A or B antibodies using human A and B RBCs. There was complete consistency among the results obtained using all of the above methods, except that no determination could be made from staining of RBCs in one pig. Staining of buccal mucosal cells proved to be the preferred method in all three species because: (i) expression of A or H antigen is weak on pig RBCs, making an accurate blood type determination difficult, and A, B, and H expression is non-existent on baboon and monkey RBCs, (ii) neither venepuncture nor organ biopsy is necessary, (iii) time-consuming adsorption of anti-human antibodies from the sera of the test animal is not required, and (iv) it proved a quick method of evaluation.

Chemistry of Blood Type

The molecules for this month come from a paper on structural factors determining blood type.

Glycosyltransferases A and B: Four Critical Amino Acids Determine Blood Type

Human A, B, and O blood type is determined by the presence or absence of distinct carbohydrate structures on red blood cells. Type O individuals have α-fucose(1→2)galactose disaccharides [O(H) structures] on their cell surfaces while in type A or B individuals, the O antigen is capped by the addition of an α- N-acetylgalactosamine or α-galactose residue, respectively. The addition of these monosaccharides is catalyzed by glycosyltransferase A (GTA) or glycosyltransferase B (GTB). These are homologous enzymes differing by only 4 amino acids out of 354 that change the specificity from GTA to GTB. In this review the chemistry of the blood group ABO system and the role of GTA, GTB, and the four critical amino acids in determining blood group status are discussed.

Substitution of transferrin by FeCl3 in the development of a low foetal calf serum concentration medium for KB-26.5 hybridoma cell line

KB-26.5, a murine hybridoma cell line producing an IgG3 monoclonal antibody used in blood type determination, primarily adapted to grow at 5% foetal calf serum (FCS) concentration has been adapted to grow at 0.5% FCS, maintaining its ability to produce antibodies at the same level. In the final step of adaptation, the addition of insulin, transferrin, ethanolamine and selenium to the media formulation was studied, using factorial assay techniques to check the effect of the different compounds and to optimize their required level for satisfactory growth and antibody secretion. KB-26.5 cells required only 20 micrograms/ml of transferrin to adapt to 0.5% FCS medium. Furthermore, transferrin could be substituted by FeCl3, at a relatively low level of 2 micrograms/ml. Maximum cell density decreased by 31.5% in spinner flask test, but the antibody titer was maintained, thus the specific productivity increased. However, inoculum size had to be increased three-fold with 0.5% FCS medium in order to assure cell growth.

Effect of the langmuir-type ion adsorption on the membrane potential of a non-charged membrane

Membrane potential is determined by the combination of the properties of ions and of the membrane. There is, therefore, a possibility that the properties of ions can be reflected on the membrane potential more effectively by artificially modifying the membrane properties. In this paper, the membrane is assumed to have no charge but to adsorb cations or anions selectively, and the effect of Langmuir-type adsorption of ions on the membrane potential is investigated theoretically. The variation of the amount of adsorbed ions affects not only the surface potential but also the diffusion potential within the membrane. The membrane potential shows a minimum or a maximum with the variation of the ion concentration in the bulk solution. This phenomenon results from the variation of the amount of ions adsorbed onto the membrane surfaces. Therefore, information on both the adsorption coefficient of a given ion and the amount of saturation of absorption of the ion is obtained from an analysis of the membrane potential. The theory is applied to the analysis of the affinity membrane potential, which can be used for the determination of blood type, and it is shown that the theory is in good agreement with experimental data.

Uridine Diphosphate-N-acetyl-d-galactosamine:d-Galactose α-3-N-Acetyl-d-galactosaminyltransferase, a Product of the Gene That Determines Blood Type A in Man

Abstract An N-acetyl-d-galactosaminyltransferase which occurs in human milk from donors of blood type A or AB but not in milk from donors of blood type B or O has been purified 55-fold, and its properties have been studied. The enzyme catalyzes the following reaction which results in the formation of structural determinants of blood type A. [see PDF for equation]