Examination of human leucocytes for the ABO, MN, Rh, Tja, Lutheran and Lewis systems of antigens by means of mixed erythrocyte-leucocyte agglutination

Robin Coombs: his life and contribution to haematology and transfusion medicine

Robin Coombs was the last survivor of the distinguished group of immunologists that included Philip Gell, John Humphrey, John Marrack, Peter Medawar and Robert White and who were responsible for the renaissance of British Immunology after the Second World War. He is best remembered for describing the antiglobulin test that bears his name. The antiglobulin test revolutionised the diagnosis of haemolytic diseases and the compatibility testing of blood for transfusion. In all, Coombs authored over 200 scientific papers. Haemagglutination reactions became widely used in the diagnosis of a range of infectious agents. Together with Philip Gell, he devised the classification of allergic reactions; these were published in the textbook "Clinical Aspects of Immunology", which he and Gell first edited in 1963 and which became the leading textbook on medical immunology. Robin Coombs was also one of the founders of the British Society for Immunology.

The evolution of pretransfusion testing: from agglutination to solid-phase red cell adherence tests

Hospital transfusion services and blood centers still use manual hemagglutination tests for most of their serological procedures. Automation of hemagglutination reactions has proven to be difficult, primarily because hemagglutination lacks an objective endpoint which can be easily interpreted by inexpensive instruments. Alternatively, solid-phase red cell adherence assays for ABO cell and serum grouping, Rh typing, red cell and platelet antibody screening, red cell and platelet crossmatching, IgA deficiency screening, hepatitis B surface antigen, and HIV antibody screening have been developed. The performance of these assays compares favorably with current hemagglutination and enzyme immunoassay methods. All of these tests share a common objective endpoint of adherence or nonadherence of indicator red cells. This uniformity allows easy interpretation of results visually, spectrophotometrically, or by image analysis. The latter technique has the potential to revolutionize the reading and interpretation of all agglutination tests. Solid-phase red cell adherence tests in microplates are ideal for batch processing large numbers of specimens. However, adherence tests are not restricted to this format. Therefore, blood grouping dipsticks have been produced, which permit testing of individual blood samples even outside of the laboratory.

The red cell antigens A, B, D, U, Ge, Jk3 and Yta are not detected on human granulocytes

We report the inability to detect the following red blood cell antigens on human granulocytes: A, B, D, U, Gerbich (Ge), JkaJkb (Jk3) and Cartwright (Yta). To study each antigen, granulocytes were purified on density gradients, fixed in glutaraldehyde, and the uptake of specific antisera measured using two direct immunological techniques: 125I-staphylococcal protein A (125I-SPA) binding and avidin-biotin-complex (ABC) immunoperoxidase staining. Glutaraldehyde fixation was shown not to affect the antigenicity when the antisera were tested using red blood cells. Using three anti-A, three anti-B and three anti-A,B antisera, our 125I-SPA results of 47 tests with granulocytes from group A individuals and 39 tests with granulocytes from group B individuals indicate that A or B antigens are not expressed on human granulocytes. Tests using ABC were also negative with 37 and 36 granulocytes from group A or B individuals, respectively. In addition, no positive results using 125I-SPA were obtained with granulocytes from individuals having antigen positive red cells when tested with two anti-D (number of tests performed (n = 22), three anti-Ge (n = 22), three anti-U (n = 20), two anti-Jk3 (n = 17), and three anti-Yta (n = 25); control anti-NA1 or -NB1 antisera were invariably positive. Also, using these antisera, no positive results were obtained by ABC except with one anti-Yta antiserum which was positive with one of seven granulocytes tested. This anti-Yta was also positive with three of 10 granulocytes by 125I-SPA. This activity was shown to be due to a granulocyte-specific antibody; adsorption of the antiserum with human granulocytes removed all activity against granulocytes but did not reduce the activity against red cells. Thus, our results are in agreement with recent reports which demonstrated the absence of the A, B and D antigens on human granulocytes. However, we have been unable to confirm previous reports which indicated the presence of the U, Ge and Jk3 antigens on human granulocytes. Also, we have been unable to detect the Yta antigen on human granulocytes.

Absence of ABH antigens on neutrophils

Many investigators have concluded that polymorphonuclear leucocytes (PMN) express ABH antigens in parallel to red cells (RBC). We have examined human PMN for ABH antigens using human isoantibodies and mouse monoclonal antibodies with three highly sensitive and specific two-stage assay systems: fluorescence flow cytometry, immunofluorescence microscopy, and avidin-biotin immunoperoxidase microscopy. In all three assays the ABH antigens could not be detected on the surface of PMN. Previous reports alleging that ABH antigens occur on PMN probably represent false positive reactions due to inherent technical problems.

An antibody to human thymic Hassall's body epithelium recognizes a subset of blood group A antigens

TE-19, a mouse monoclonal antibody (mAb) against thymic Hassall's body epithelium, was investigated because of its cross-reactivity with human erythrocytes. Antibody TE-19 was found to react only with group A erythrocytes, though it reacted with Hassall's body epithelium from donors of all blood group phenotypes. TE-19 antibody bound preferentially to cells of subgroup A1, and reacted only weakly with A2 and Aint erythrocytes. Although it apparently bound to A antigen with both glycolipid and glycoprotein backbones, TE-19 antibody only reacted with A antigenic moieties containing long or branched chain structures. Analysis of TE-19 reactivity with erythrocyte membrane components using electroblotting and immunostaining techniques showed antibody reactivity with components migrating in the areas of band 4 X 5 and just ahead of the dye front, consistent with membrane glycolipid. It is possible that all human thymic Hassall's bodies contain epithelial cells which, irrespective of the donor's erythrocyte blood group, bear a carbohydrate antigen similar to A antigen.

Solid-phase techniques in blood transfusion serology

For nearly a century, erythrocyte agglutination has persisted as the most widely used method for the demonstration of antigen-antibody reaction in immunohematology. So far, no other system has been developed which can match its simplicity, versatility, and general reliability. The major disadvantage of agglutination reactions is the lack of an objective endpoint, which has severely hindered attempts to automate routine pretransfusion tests. To overcome this problem, we have designed a series of solid-phase assays for ABO and Rh grouping, antibody screening, compatibility, and hepatitis tests. Each of these solid-phase assays shares a common endpoint of red cell adherence, which is easily interpreted visually or spectrophotometrically. Computer interface permits the automatic interpretation and recording of results. We believe this solid-phase system should finally bring the blood bank laboratory into the age of automation.

Human erythrocyte antigens. Regulation of expression of a novel erythrocyte surface antigen by the inhibitor Lutheran In(Lu) gene

Our study describes a novel human erythrocyte protein antigen, the expression of which is regulated by the rare Lutheran inhibitor In(Lu) gene. We have produced a monoclonal antibody (A3D8) that bound strongly to erythrocytes from subjects with Lutheran phenotypes Lu(a+b+), Lu(a+b-), and Lu(a-b+) but bound negligibly to erythrocytes from subjects with the dominant form of Lu(a-b-) phenotype, reflecting inheritance of the In(Lu) gene. Importantly, erythrocytes from an individual with the recessive form of Lu(a-b-) phenotype (i.e., absence of the In(Lu) gene and absence of genes encoding for Lutheran antigens) showed reactivity with A3D8 antibody comparable to that seen with Lu(a+) or Lu(b+) erythrocytes. A3D8 antigen activity was also found on all leukocytes and in serum and plasma; this activity also appeared to be regulated by the In(Lu) gene in serum, plasma, and on a subset of leukocytes. Thus, we have identified a human erythrocyte protein whose expression is modified by the In(Lu) gene. This knowledge that such an antigen exists on erythrocytes and in normal plasma should allow further studies into the molecular genetics of the In(Lu) gene and into the functional and structural significance of the A3D8 antigen.

Regeneration of peripheral blood cells following ABO incompatible allogeneic bone marrow transplantation for severe aplastic anaemia

The regeneration of peripheral blood cells in six patients receiving ABO incompatible bone marrow transplants for severe aplastic anaemia has been studied. The results are compared with those of 18 similar aplastic patients treated with ABO compatible transplants. Reticulocyte recovery in the ABO incompatible cases was significantly delayed (P less than 0.01) and associated with greatly prolonged red cell transfusion requirements (P less than 0.001). Peripheral blood regeneration of neutrophils, lymphocytes and platelets was also significantly delayed (P less than 0.01). Platelet support was required for longer in the ABO incompatible cases (P less than 0.001) but there was no increase in the incidence or severity of infections in the post transplant period.

Maternal lymphocytotoxic antibodies and bilirubin levels in the postpartum offspring

HLA antigens are present on immature red cells (Harris & Zervas 1969), but disappear from their surface when they become mature and enter into the circulation (Silvestre et al. 1970). Nevertheless some remnants of HLA substance may survive this antigenic switch and possibly persist on adult red cells (Morton et al. 1969, 1971, Doughty et al. 1973). A shortened survival of HLA incompatible reticulocytes has been reported when they are transfused into recipients with circulating anti-HLA antibodies (Zervas et al. 1972). As to anti-HLA antibodies possibly reacting with erythrocytes in cases of fetomaternal immunization, Moulinier (1970) claimed that they would potentiate any hemolytic process in newborns of Rh-immunized women, but successive investigations failed to confirm this (Ahrons & Glavind-Kristensen 1971, Nymand 1975). Also, Nymand (1975) found no association between lymphocytotoxic antibodies in mothers and high bilirubin levels in the umbilical cord blood collected at delivery. On the contrary, when the onset of neonatal jaundice in the postpartum offspring was monitored, newborns of mothers with lymphocytotoxins appeared to become jaundiced more frequently than expected (Reekers et al. 1975). The present study has been undertaken to investigate the relationships between complement dependent lymphocytotoxins (CdL) in the mothers and the bilirubin levels in the newborns during the first days of life.

The detection of granulocyte alloantibodies with an indirect immunofluorescence test

An indirect immunofluorescence technique for the detection of alloantibodies against granulocytes was developed. A major problem was the unspecific fluorescence of granulocytes, due to unspecific adherence of immunoglobulins to the cell membrane. This could be suppressed by the prefixation of the granulocytes with paraformaldehyde. The developed test proved to be specific and sensitive and to have a high reproducibility. Strongly positive reactions were obtained with antisera containing granulocyte-specific agglutinins or granulocyte-cytotoxins, but also with some sera that did not react in either the agglutination or the cytotoxicity test. HLA antisera also gave positive reactions, but strong anti-A, anti-B or anti-D sera did not react. With this technique leucocyte antibodies can be detected in a higher percentage of patients with febrile transfusion reactions.

Antibodies and human transplant rejection

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