Dr(a-) polymorphism of decay accelerating factor. Biochemical, functional, and molecular characterization and production of allele-specific transfectants.

The Dra antigen belongs to the Cromer-related blood group system, a series of antigens on decay accelerating factor (DAF), a glycosyl-phosphatidylinositol-anchored membrane protein that protects host cells from complement-mediated damage. We studied the rare inherited Dr(a-) phenotype to ascertain the associated biochemical and functional changes in DAF and to characterize the basis for this polymorphism. Radioimmunoassay assay and flow cytometric analysis of Dr(a-) erythrocytes demonstrated 40% of normal surface expression of DAF but normal levels of several other glycosyl-phosphatidylinositol-anchored proteins, distinguishing this phenotype from that of paroxysmal nocturnal hemoglobinuria. Western blots confirmed this reduced DAF expression and indicated a slightly faster mobility of the molecule on SDS-PAGE. Despite the reduced DAF expression, Dr(a-) erythrocytes functioned normally in the complement lysis sensitivity assay. Utilization of the polymerase chain reaction to amplify mononuclear cell genomic DNA from three unrelated Dr(a-) individuals demonstrated that a point mutation underlies the Dr(a-) phenotype: a C to T change in nucleotide 649 resulting in a serine165 to leucine change. This defines the Drb allele of DAF, which can be distinguished from Dra by a Taq I restriction fragment length polymorphism. We created transfected Chinese hamster ovary cell lines expressing either the Dra or the Drb allelic form of DAF. These allele-specific transfectants were tested by inhibition of hemagglutination or flow cytometry and confirmed the specificity of anti-Dra alloantisera. The allele-specific transfectants could form the basis of a new serological approach to immunohematology.

Rare blood donors: a personal approach.

The National Blood Group Reference Laboratory (NBGRL) in Israel was established in Jerusalem in 1971 and transferred to Magen David Adom (MDA), National Blood Services in 1995. This laboratory was the inspiration of the first author of this article for over 30 years. The realization of this vision was made possible by the cooperation of colleagues and laboratory workers in blood transfusion services throughout the country. The aim of the service was to provide diagnostic help in resolving immunohematologic problems found in the blood banks and clinics in Israel. In the beginning, only a part-time technician performed the work and testing was done using very limited reagents. The service was expanded by personal visits to all of the 22 blood banks in Israel to explain the aim of this new service and to educate them about the importance of resolving each and every case. One major issue was the cost involved in referring problems but it was decided at the outset that these would be covered by the government to ensure that a workup would be performed for all referred cases. The expansion of the service could not have been achieved without the help of the SCARF program. This voluntary service enabled us to identify the first rare donors in Israel, resolve complex cases, and find compatible blood for our patients. To illustrate the importance of the NBGRL in Israel and the rapid resolution of cases referred, several individual stories are described. The purpose of this review is to show the importance of the NBGRL in identifying rare blood groups and in providing and coordinating services and the importance of keeping in close contact with the rare donors to encourage and promote their donations, which may save lives.

H-deficient Bombay and para-Bombay red blood cells are most strongly agglutinated by the galactophilic lectins of Aplysia and Pseudomonas aeruginosa that detect I and P1 antigens.

The galactophilic lectins Aplysia gonad lectin (AGL) and Pseudomonas aeruginosa lectin (PA-IL), which detect human I and P1 RBC antigens, were examined for hemagglutination of H+ (group O and B) and H-deficient (Bombay and para-Bombay phenotype) RBCs. The results were compared with those obtained using two other galactophilic lectins, Maclura pomifera lectin (MPL) and Arachis hypogaea (peanut) agglutinin (PNA), which share T-antigen affinity, and two fucose-binding H-specific lectins, Ulex europaeus (UEA-I) and Pseudomonas aeruginosa lectin (PA-IIL), as well as with those achieved with anti-I serum. The results revealed that, in contrast to UEA-I and PA-IIL, which preferentially agglutinated H+ RBCs, and to MPL and PNA, which similarly agglutinated all examined RBCs, AGL, PA-IL, and the anti-I serum agglutinated the H-deficient RBCs more strongly than did the H+ RBCs. These findings could be attributed to increased levels of I and P1 antigens on those RBCs resulting from the use of the free common H-type 2 precursor for their synthesis. Since both PA-IL and PA-IIL are regarded as potential pathogen adhesins, it would be interesting to statistically compare the sensitivities of individuals of H+ and H-deficient RBC populations to P. aeruginosa infections.

The effect of hypoxia on collagen synthesis in cultured 3T6 fibroblasts and its relationship to the mode of action of ascorbate.

When exposed to low oxygen tension, in the absence of added ascorbic acid 3T6 mouse fibroblast cultures in late log phase respond by increased lactate production and increased hydroxylation of proline in nascent collagen, which is paralleled by an increase in prolyl hydroxylase activity. After 6 h recovery from the anoxic stimulus, however, cultures still yield more prolyl hydroxylase than controls, but the effect on hydroxylation of nascent collagen has disappeared. These observations help to dissect the dual role of ascorbate which can stimulate hydroxylation both by increasing the amount of active enzyme and by a cofactor-like role; in addition, these observations may be relevant to wound healing.

Persistent anti-Dra in two pregnancies.

The Drori (Dr(a)) antigen is one of the ten high-prevalence antigens of the Cromer blood system, which are carried on decayaccelerating factor (DAF, CD55). The Dr(a-) phenotype was first described in a 48-year-old Jewish woman from Bukhara. Her serum contained an antibody to a high-prevalence antigen named anti-Dra. Most known individuals with the Dr(a-) phenotype are Jews from the geographic area of Bukhara, but individuals from Japan have also been described. Antibodies in the Cromer blood group system, including anti-Dra,have never been reported to cause HDN. In most of the cases with anti-Dra examined in Israel, the antibodies have been subtyped as IgG2 and IgG4. This report is of a woman with Dr(a-) phenotype and an anti-Dr(a) titer of 256 to 512 in her serum, observed during two successive pregnancies. At birth, the RBCs of the first- and second-born child were negative and positive in the DAT, respectively, and neither manifested clinical signs of HDN. The disappearance of Cromer system antibodies, including anti-Dra in midpregnancy, has been described in a previous study. In that study, it was theorized that the antibodies in the serum of the women were adsorbed onto placental DAF. The finding of a high anti-Dra titer in two successive pregnancies in this patient, with a positive DAT for the RBCs of one of the two babies at term, differs from published reports, suggesting that a different mechanism might be involved.

Some factors regulating collagen polymorphism in cultured porcine and bovine aortic endothelium.

The apparently random behaviour of the collagen profiles of cultured bovine and porcine aortic endothelium, both in the cells and the medium, has been studied. Despite the fact that these cells retain their normal cobblestone appearance, the collagen profile in each case changes over a period of 12 days in culture following confluence, the changes following distinct patterns. Varying the serum concentration from 2 to 20% in the culture medium has no effect on the collagen types produced. It thus appears that regulatory mechanisms do exist to control collagen polymorphism and that, in this system, the age of normal cobblestone cells in culture constitutes one factor whilst the occurrence of sprouting (angiogenesis), as reported previously, constitutes a second.

The effect of hypoxia on the synthesis of collagen and glycosaminoglycans by cultured pig aortic endothelium.

Porcine aortic endothelium cultured at 20% oxygen concentration synthesizes collagen and three of its marker enzymes - proline and lysine hydroxylases and lysine oxidase, the cross-link enzyme. It also synthesizes and secretes hyaluronic acid, dermatan sulphate, possibly heparan sulphate, large amounts of chondroitin 4-sulphate and smaller amounts of chondroitin 6-sulphate. Growth of these cells for 24 h in 0%, or 2% oxygen results in little change in cell numbers or cell protein but a fall in collagen synthesis and in proline and lysine hydroxylases, but a rise in lysine oxidase. There is a considerable increase in synthesis and secretion of all the glycosaminoglycans found. The cell lipids appear qualitatively unchanged. Apart from increased lysosomes seen at 0% oxygen, no ultrastructural changes appear to occur. These findings illustrate the lability of the endothelial response to oxygen lack.

Phenotypic changes in morphology and collagen polymorphism of cultured bovine and porcine aortic endothelium.

Endothelial cells derived from the pig aorta grow in culture with typical cobblestone morphology; after about 7 days they elongate to a more fibroblastic appearance followed by the appearance of sprouts. The sprouts can be removed by 24 h treatment with either 8-bromo-cyclic AMP or cholera toxin, when the cells revert to their original cobblestone morphology. Examination of phenotypic markers as exemplified by the collagen types synthesised in the cell layer and those released into the medium, indicated the presence of types I, III and V in the cobblestone phase; the result of sprouting and desprouting was to alter the various proportions of I, III and V in both cells and medium with the exception that type V disappeared from the medium of sprouting porcine cells. When bovine endothelial aortic cells were similarly examined, I, III and V type collagens were found in the cell layer and medium, but in vastly different proportions from those found in the pig. Sprouting and desprouting bovine endothelium produced profound changes--in the cell layer, only type V could be demonstrated, whereas I, III and V were demonstrable in the medium, albeit in differing proportions. The conclusions are firstly, that phenotypic morphological changes may or may not be accompanied by phenotypic changes in the synthesis of the various collagen markers; secondly, that the secreted collagens do not always reflect those collagens retained by the cell layer which shows sequestration of one of the collagen types; finally there is a very distinct species difference and it is not possible to extrapolate from one species to another. The ultrastructural observation that the sprouts in cultured bovine endothelium resemble everted capillaries adds value to the culture as a model system.

H blood group detection by the L-fucose binding lectin of the green marine alga Ulva lactuca.

Extracts of the green marine alga Ulva lactuca collected along the seashore of Tel-Aviv exhibit hemagglutinating activity towards papain-treated human erythrocytes. This hemagglutinating activity was shown to be inhibited by L-fucose and EDTA, and to be relatively resistant to heating at 60 degrees C, while sensitive to low pH. Like the lectin of Ulex europeus, the Ulva lectin exhibits blood group H specificity. It agglutinates most strongly erythrocytes of blood group 0(H) followed by B greater than A greater than AB. A2 and A2B erythrocytes are agglutinated by it considerably more strongly than A1 and A1B respectively. Bombay 0(hh) type erythrocytes are almost non-reactive. The lectin can be stored at -20 degrees C for years.

Genetics of insulin dependent diabetes mellitus in Israel: population and family study.

The association between insulin dependent diabetes mellitus (IDDM) and the HLA system was studied in two groups of Jewish patients: 50 Ashkenazim and 42 non-Ashkenazim. The pattern of association of HLA-A and B locus antigens was somewhat different from that observed in European Caucasian patients. HLA-B8 had a higher frequency; B15 and Cw3 were rare in the population studied and were less frequent in IDDM patients than in controls. On the other hand, the frequency of A26, B18, and Bw38 was increased in Ashkenazi patients, but not in non-Ashkenazim, who in turn showed an increase for Bw51. Although the association between IDDM and HLA-A and B locus antigens shows a marked variability in different populations, the association with HLA-DR3 and DR4 is constant feature. There was a typical excess of DR3/DR4 heterozygotes in both patient groups. This heterozygote type carries the highest relative risk, followed by DR4/DR4 homozygotes. These data can well be interpreted by a model of two different HLA-linked susceptibility genes, one associated with DR3 and the other one with DR4, that interact so that different genotypes are associated with different levels of penetrance. This model received further support from studies in 15 multiple case families where there is an excess of affected sib pairs sharing two DR antigens.

Genetic polymorphisms among Iranian Jews in Israel.

Iranian Jews represent a very ancient Jewish community with a high frequency of inbreeding. A sample of Iranian Jews, mainly unrelated students, was tested for genetic markers of red blood cells and serum. The frequency of glucose-6-phosphate dehydrogenase deficiency was not uniform among Jews who had lived in different areas of Iran; it was lower among those from central Iran (6.7%) than in those from southern and western Iran (16.7% and 20.6%, respectively). The frequencies of B, CDe, cDE, S, and K alleles were among the highest recorded in Jewish ethnic groups. Iranian Jews were similar to Iraqi Jews with respect to the frequencies of the blood markers B, CDe, cde, cDe, ACP, PGM1, ADA, and Hp; however, the B and CDe markers occur with similar frequencies among indigenous Iranians. The presence of the cDe allele and the Gm1,5,13,14,17 haplotype in low frequencies indicates black admixture. Mongoloid admixture is indicated by the polymorphism of the Gm1,13,15,16,17 haplotype. The very rare phenotype Gm(3,5,13,14,17) was observed in 4.8% of 167 individuals tested. This phenotype has not been previously observed among Jews.

Genetic polymorphisms among Bukharan and Georgian Jews in Israel.

Bukharan and Georgian Jews have lived in central Asia for many centuries. Approximately 30,000 Bukharan and 37,000 Georgian Jews lived in their respective countries within the USSR between 1920 and 1960. Genetic markers of blood--blood groups, isoenzymes, HLA antigens, and gamma and kappa chain allotypes--were tested in blood samples from 113 Bukharan and 134 Georgian Jews living in Israel. Estimates of inbreeding were low: alpha = 0.0088 for Bukharan and alpha = 0.0011 for Georgian Jews. G6PD deficiency was relatively rare in Bukharan (2.2%) and in Georgian Jews (6.0%), when compared to other Jews in the area. Both populations showed frequencies of some markers similar to that of other Jewish populations, but frequencies of several markers were extremely high or low. Bukharan Jews showed very high frequencies of B(0.243), cDe (0.122), JkA (0.705), HLA-A29 (0.167), A30 (0.116) and B7 (0.124), and AcPA (0.451) and very low ones of O(0.518), CDe(0.422), AcPB (0.513) and GLO1 (0.140). Very high frequencies in Georgian Jews were observed for cDE (0.189), HLA-A3 (0.194), Bw35 (0.300) and GLO1 (0.367). Yet the greatest difference between both populations was in African characters. While in Bukharan Jews Fy was very frequent (0.146) and cDe was the highest observed among Jews (0.122), neither of these markers was detected among the Georgian Jews tested. Yet, another African character, the Gm1,5,10,11,13,14,17,26 haplotype, occurred in both populations (0.028 and 0.042 in Bukharan and Georgian Jews, respectively). Distance measures for Bukharan, Georgian, Iranian, Cochin, and Libyan Jews based on 13 polymorphic loci showed the greatest distance between Cochin Jews and the other populations and the smallest distance between the Georgian and Iranian Jews.

Genetic studies on Cochin Jews in Israel: 1. Population data, blood groups, isoenzymes, and HLA determinants.

The period in which Jews were first associated with Cochin and the Malabar coast was by tradition, after the destruction of the First Temple (586 BCE). Yet, the earliest evidence of Jewish settlements is from the tenth century CE. The largest group of Cochin Jews are the "Black Jews," of whom about 4,000 live in Israel. A high frequency of consanguineous marriages prevailed among Cochin Jews. Their mean height and weight were low when they came to Israel in 1954; an increase in both was observed 20 years later. Some of the allele frequencies of blood groups, isoenzymes, and HLA antigens were similar to those in other Jewish communities. In the high O, M, cde, and HLA-A28 and the low cDE allele frequencies Cochin Jews resembled Yemenite Jews. A few allele frequencies, the high Fya, AK2 and the low Jka and Hp1, were similar to those observed in indigenous southern Indian populations. In most HLA antigen and haplotype frequencies the Cochin Jews showed a distribution similar to that observed in other Jews and Caucasoids. No comparable HLA data on southern Indian populations were available. The results indicate that Cochin Jews have similarities with Jews, in particular Yemenite Jews, and with the indigenous populations of southern India.

Genetic studies on Cochin Jews in Israel: 2. Gm and Inv data--polymorphism for Gm3 and for Gm1,17,21 without Gm(26).

Serum samples from 223 Jews from Cochin, India were tested for Gm(1,2,3,5,6,13,14,17,21,26) and for Inv(1). Certain samples were also tested for Gm(15) and Gm(16). The Cochin Jews are polymorphic for: 1) Gm3, a haplotype that does not lead to the formation of gamma 3, as was shown by tests of the serum of a homozygote, and 2) Gm1,17,21, a haplotype lacking Gm(26), which is ordinarily present in this haplotype. The Gm data indicate considerable admixture with southern Indians. There is no evidence for African admixture, such as has been found for all other Jewish populations studied thus far. The Inv data are similar to those for other Jewish populations.

Autologous blood transfusions and pregnancy.

The application of autologous and frozen red blood cell (RBC) programs is described for 3 pregnant women with antibodies to high-incidence blood group antigens (anti-Lutheranb, anti-Cellano, anti-Vel). The cases illustrate how readily available supplies or rare blood types can be maintained throughout pregnancy using autologous and frozen RBC techniques, including selective predeposit, "family-sharing," and intensive phlebotomy with fluid replacement. The RBC phenotypes described in this paper are exceedingly rare since they occur in only 0.1-0.001% of random donors. However, the principles of autologous blood transfusions are universal and they can be applied to the general problems of blood group incompatibility in pregnancy.

Anti-PP1Pk (anti-Tja) and habitual abortion.

Blood group incompatibility as a cause of early or habitual abortion has been a matter of much debate. However, the abortion rate in such cases is much higher than that found in the general population. Two sisters having the rare genotype pp and anti-PP1Pk (anti-Tja) in their serum were reported as having habitual abortions; a third sister, with a normal P group, had a normal obstetric history. The relationship of anti-PP1Pk (anti-Tja) to the high rate of habitual abortion was discussed and added support was given to the existing evidence that certain maternal blood group antibodies can affect embryos early in uterine life.

Biochemical and ultrastructural study of the effects of proline analogues on collagen synthesis in 3T6 fibroblasts.

The effects of proline analogues, L-3,4-dehydroproline and L-azetidine-2-carboxylic acid, on collagen synthesis by cultured 3T6 fibroblasts have been studied. Prolyl hydroxylase activity was partially inhibited in cells cultured with dehydroproline for 24 h, resulting in the synthesis of collagen in which the proline was underhydroxylated. Azetidine had no effect on prolyl hydroxylase and less effect on the degree of hydroxylation of proline. Fibroblasts grown in the presence of either analogue and fixed in-situ contained greatly distended cisternae of the rough endoplasmic reticulum. Proline analogues otherwise caused few ultrastructural changes in the cells. Treated cells which had been handled more roughly during preparation for electron microscopy contained many large cytoplasmic vacuoles in addition to dilated cisternae. Our results indicate that the major effect of the proline analogues was the inhibition of prolyl hydroxylation. However, electron microscopy of the treated cells revealed hitherto unreported cytoplasmic damage.