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.

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.

Molecular defects underlying the Kell null phenotype.

Expression of the Kell blood group system is dependent on two proteins, Kell and XK, that are linked by a single disulfide bond. Kell, a type II membrane glycoprotein, is a zinc endopeptidase, while XK, which has 10 transmembrane domains, is a putative membrane transporter. A rare phenotype termed Kell null (Ko) is characterized by the absence of Kell protein and Kell antigens from the red cell membrane and diminished amounts of XK protein. We determined the molecular basis of eight unrelated persons with Ko phenotypes by sequencing the coding and the intron-exon splice regions of KEL and, in some cases, analysis of mRNA transcripts and expression of mutants on the cell surface of transfected cells. Six subjects were homozygous: four with premature stop codons, one with a 5' splice site mutation, G to A, in intron 3, and one with an amino acid substitution (S676N) in exon 18. Two Ko persons with premature stop codons had identical mutations in exon 4 (R128Stop), another had a different mutation in exon 4 (C83Stop), and the fourth had a stop codon in exon 9 (Q348Stop). Two Ko persons were heterozygous for two mutations. One had a 5' splice site mutation (G to A) in intron 3 of one allele that caused aberrant splicing and exon skipping, and the other allele had an amino acid substitution in exon 10 (S363N). The other heterozygote had the same amino acid substitution in exon 10 (S363N) in one allele and a premature stop codon in exon 6 (R192Stop) in the other allele. The S363N and S676N mutants, expressed in 293T cells, were retained in a pre-Golgi compartment and were not transported to the cell surface, indicating that these mutations inhibit trafficking. We conclude that several different molecular defects cause the Kell null phenotype.

A comparison of the Aplysia lectin anti-I specificity with human anti-I and several other I-detecting lectins.

BACKGROUND: Lectins displaying blood group specificity are important for blood group typing and antigen recognition. Their use in blood banks is especially widespread in situations where there is a shortage of specific antisera. This report describes the efficiency of Aplysia gonad lectin as a reliable reagent for the detection of I antigen, which is common on adult human cells but reduced in fetal, newborn, and rare adult red cells. STUDY DESIGN AND METHODS: The selective hemagglutinating activity of the Aplysia lectin was compared with that of human anti-I and several I-reactive lectins, including two plant lectins, one galactophilic microbial lectin, and bovine spleen galectin. RESULTS: The comparison has revealed that Aplysia gonad lectin, like human anti-I, strongly agglutinates and adsorbs to adult I-positive red cells, differentiating between them and fetal or rare I-negative adult red cells (although with less of a difference). In contrast to the plant and microbial lectins examined, its I-affinity does not depend on the presence of ABH or P system antigens and it clearly detects higher I antigen expression in Oh red cells. The hemagglutinating activity of Aplysia lectin as that of all the I-detecting proteins is enhanced at 4 degrees C, but unlike the human anti-I Aplysia lectin-induced hemagglutination is stable at room temperature. CONCLUSIONS: The Aplysia lectin is a reliable anti-I reagent, which strongly agglutinates I-positive adult human red cells irrespective of their ABH or P system antigens. This lectin is usable at room temperature.

Glycophorin A mutation Ala65 --> Pro gives rise to a novel pair of MNS alleles ENEP (MNS39) and HAG (MNS41) and altered Wrb expression: direct evidence for GPA/band 3 interaction necessary for normal Wrb expression.

We report here a novel Glycophorin A (GPA) mutation Ala65 --> Pro which gives rise to a low-incidence antigen HAG, lack of a high-incidence antigen ENEP and aberrant expression of the high-incidence Wrb antigen. Anti-ENEP was identified in the serum of a transfused male patient (E.H.) who was homozygous for a GPA Ala65 --> Pro mutation and possessed a novel low-incidence antigen which we have called HAG. An unrelated HAG-positive individual, heterozygous for the Ala65 --> Pro mutation, has also been identified. Anti-HAG was present in several multispecific antisera to low-incidence antigens and in one monospecific serum. Normal expression of the Wrb antigen depends on the presence of amino acid Glu658 of band 3 and on the presence of GPA. However, a specific epitope on GPA has not previously been implicated. DNA sequence analysis of band 3 from patient E.H. was normal in the region of Wra/Wrb polymorphism with homozygous presence of Glu658 and therefore the abnormal Wrb expression results from the Ala65 --> Pro mutation in GPA. The ENEP and HAG antigens have been assigned the MNS blood group system numbers 002.039 and 002.041, respectively, by the ISBT Working Party on Terminology for Red Cell Surface Antigens.

An Israeli family with six cisAB members: serologic and enzymatic studies.

BACKGROUND: The cisAB blood type is a rare phenomenon in which both the A and B blood types are inherited from a single parent. Several forms of this phenotype have been characterized that differ with respect to serologic reactions and the activities of the gene-encoded blood group A and B transferases. STUDY DESIGN AND METHODS: The cisAB blood type was suspected when a baby typed as blood group O was born to a mother whose blood group was AB. Family studies revealed four generations in whom the pattern of inheritance could be explained only by the inheritance of the cisAB genotype. Blood and saliva samples from the family were tested serologically and assayed for the relevant glycosyltransferases. Samples suitable for DNA analysis were not available. RESULTS: Six family members were shown serologically to be of the cisAB type. The A and B transferases in the sera of these individuals were 20 to 35 and 25 to 50 percent of those obtained for A and B individuals, respectively. The enzymic characteristics of the A and B transferases were determined. The A transferase in the sera of the cisAB persons did not bind to agarose beads. CONCLUSION: The family described carries the cisAB gene, which encodes production of A and B transferases that differ from those of "normal" A, AB, and B controls. This variant has properties that are distinctly different from those described in other reports.

Dr(a) (Cromer-related blood group antigen)-incompatible renal transplantation.

BACKGROUND AND OBJECTIVES: Cromer system antigens, a series of blood group antigens of very high frequency, are not considered to be clinically significant in transfusion. In renal transplantation only the ABO blood group antigens are considered essential. The Drori blood group antigen is present in serum and has been found to reside on the renal tubular basement membrane and Bowman's capsule. The effect of anti-Dra on the renal parenchyma has not been evaluated. MATERIALS AND METHODS: A unique case of renal transplantation of an incompatible Dr(a+) kidney to a Dr(a-) patient with anti-Dra in her serum is presented. RESULTS: Graft function was immediately good. The titer of anti-Dra remained unchanged following transplantation. CONCLUSION: The successful outcome of a case of a Drori (Dra)-incompatible kidney transplantation confirmed the lack of clinical significance of the anti-Dra relating to transplantation.