Search

Naturally occurring anti-Kp a antibody is extremely rare and was first reported in 1957, named after the first producer 'Penney'. However, the subsequent anti-Kp a reports presented were all anti-Kp a due to isoimmunization. Individuals with severe bacterial infections particularly Gram-negative bacteria are known to be capable of producing cross-reactive antibodies against Kell blood group system. However, such uncommon antibodies like anti-Kp a can be easily missed in routine pre-transfusion testing unless the panel cells containing low incidence antigen are used for antibody screening. Here, we report a case of naturally occurring anti-Kp a antibody, identified incidentally during pre-transfusion testing of a 12-month-old female infant with the diagnosis of Niemann-Pick disease and recurrent bacterial (Escherichia coli) infection., (© 2021 International Society of Blood Transfusion.)

The X-linked McLeod syndrome is defined by absent Kx red blood cell antigen and weak expression of Kell antigens, and this constellation may be accidentally detected in routine screening of apparently healthy blood donors. Most carriers of this McLeod blood group phenotype have acanthocytosis and elevated serum creatine kinase levels and are prone to develop a severe neurological disorder resembling Huntington's disease. Onset of neurological symptoms ranges between 25 and 60 years, and the penetrance of the disorder appears to be high. Additional symptoms of the McLeod neuroacanthocytosis syndrome that warrant therapeutic and diagnostic considerations include generalized seizures, neuromuscular symptoms leading to weakness and atrophy, and cardiopathy mainly manifesting with atrial fibrillation, malignant arrhythmias and dilated cardiomyopathy. Therefore, asymptomatic carriers of the McLeod blood group phenotype should have a careful genetic counseling, neurological examination and a cardiologic evaluation for the presence of a treatable cardiomyopathy.

63 Rh-negative male volunteers were immunized with D-positive red cells. 28 (44%) produced anti-D. To provide sustained levels of high concentration of anti-D, 18 of the 28 male volunteers have received repeated antigenic stimuli at individual intervals of 2-9 months. In all but 1 case the level of anti-D rose to between 30 and 300 microgram/ml and persisted at this level for several years. There was no evidence of a decrease in antibody response with an increase in the number of stimuli. 24 Rh-negative women immunized by pregnancy were restimulated. 16 achieved anti-D concentrations over 21 microgram/ml. The levels achieved were not influenced by the different D-positive cells injected, nor were larger antigenic doses of any benefit. No untoward clinical reactions occurred as a result of the repeated injections of antigenic material or of long-term plasmapheresis. 2 volunteers developed unwanted antibodies outside the Rh-system. Beginning in 1968, the programme to obtain anti-D plasma has yielded more than 70,000 doses of 250 microgram each, permitting the treatment of all Rh-negative women at risk.

The serum from a 50-year-old woman, Mrs. Côté, was found to agglutinate all cell samples except her own, those of two siblings, and Ko erythrocytes. Her Kell phenotype is a common: K-k+, Kp(a-b+), Js(a-b+), Ul(a-), K:12, K:13, K:14, K:18. Anti-K11 present in her serum defines a high-frequency red cell antig

Serum from a multitransfused patient with bladder papilloma was examined. The serum contained anti-Kell as well as polyspecific, cytotoxic HLA antibodies and HLA-associated haemagglutinins. The HLA haemagglutinins were demonstrated by the Auto Analyzer method and reacted predominantly with red blood cells (RBC) from HLA-A28-positive individuals, and were distinctly weaker with all other test cells. Survival studies with 51Cr-RBC from an HLA-A28-positive, Kell-negative donor with strong A28 RBC reactivity were performed. A small component of the RBC showed clearly reduced survival time, while the main component showed nearly normal survival.

Leukocytes of nine unrelated boys with X-linked chronic granulomatous disease lack Kx antigen. In three of these cases, the red cells also lack Kx and have the McLeod phenotype and abnormal morphology. X-linked chronic granulomatous disease CGD can thus be separated into two types. Type I cases have an antigenic deficiency that is restricted to the phagocytic leukocytes while in type II, the deficiency involves both leukocytes and red cells. Red cells of type II CGD patients have enhanced i antigen activity suggesting that they are under hemopoietic stress. Normal Kx synthesis is directed by an X-linked gene named X1k. Three variants, X2k, X3k, and X4k order the different permutations of leukocyte and red cell Kx antigen production that have been recognized.

The first case of interdonor incompatibility associated with granulocyte transfusion is presented. The patient received Kell positive granulocyte transfusions containing about 30 ml of red cells 36 and 132 h prior to receiving a granulocyte transfusion containing anti-Kell 1/128. The chills, fever, vomiting and hypotension resulting from the red cell incompatibility, cleared with appropriate fluid therapy. Antibody detection methods must be applied to each unit of granulocytes. The patients blood should be tested with reagent grade antibody to detect small numbers of antigen-containing cells if an antibody-containing granulocyte transfusion is to be given. Routine major and minor cross-matching is insufficient. Removal of the antibody containing plasma and resuspension of the granulocytes in plasma free of irregular antibodies may be the most effective way to prevent such incompatibility.

The abnormal erythrocyte of the McLeod phenotype displays a reduced Kell blood group expression, an abnormal morphology in about 30% of the total red blood cell population and a decrease in water permeability. These parameters have previously been shown to be independent of membrane lipid composition, microviscosity and electrolyte transport. Findings such as these seem to implicate the involvement of a defective membrane protein. The present study investigated membrane composition by utilizing two techniques: freeze-fracture electron microscopy and discontinuous polyacrylamide gel electrophoresis. Electrophoretic scans revealed no apparent band additions or deletions showing McLeod membrane protein composition to be normal. Freeze-fracture electron microscopy did show a significant increase in intramembrane particle density. These findings may be resolved by proposing a dissociation of the band 3 glycoprotein. Unlinkage of this polypeptide, thought to be involved in water transport and intramembranous particle composition, could account for the decreased water transport and increased particle density seen in the McLeod erythrocyte membrane.

Tests of three new unrelated K:-11 people and their relatives confirm that K11 is allelic to K17 (Wka) and belongs to the Kell system.

This paper gives details of a family in which there are numerous examples of the heterozygous Kdegree state. The study was initiated by the presence of anti-Kpb in the serum of the propositus. Reactions with anti-K, anti-Ku, anti-Jsb and anti-K13 confirm that the Kdegree gene in trans with Kpa results in weaker expression of these Kell antigens. One example of anti-K showed some evidence of dosage effect with kKpb/Kdegree cells, but these results were not confirmed by quantitation studies.

'Naturally occurring' anti-Kell (K1) was found in a Japanese male who has never received a transfusion. The antibody agglutinated K:1 cells suspended in saline at 4 and 22 degrees C as well as cells suspended in albumin and treated with proteolytic enzymes.

Anti-Jsa was found in a Japanese female who had never received a transfusion and had borne 3 Jsa-negative children. The antibody agglutinated Jsa cells suspended in saline and treated with proteolytic enzymes as well as reacting with those cells by the indirect antiglobulin test. This example is the first reported 'naturally occurring' anti-Jsa.

A case of auto-immune hemolytic anemia caused by auto anti-K13 is described. Direct antiglobulin tests using monospecific reagents showed that IgG and the C3 component of complement were present on the patient's red cells. Eluted auto-antibody did not react with Ko or with K:--13 cells. Kell blood group antigenicity of the patient's red cells did not appear to be reduced.

The McLeod phenotype is a rare condition characterized by deficiencies in the Kell blood group antigens of erythrocytes. The present study has defined some of the morphological and physiological characteristics of these red cells. Scanning electron microscopy reveals that approximately 27% of McLeod cells are morphologically abnormal. These aberrant forms resemble the acanthocytes of abetalipoproteinemia. Incubation experiments indicate that the morphology of McLeod erythrocytes is not due to a plasma factor. Biochemical studies reveal that the lipid composition and microviscosity of these erythrocytes are normal. In addition, isotopic tracer experiments indicate that electrolyte transport is also within the normal range. However, osmotic water permeability is approximately 30% below normal. The absence of a lipid abnormality and other experimental data suggest that the abnormal morphology and reduced H2O permeability of the McLeod erythrocyte may be due to defective membrane protein.

The antigen corresponding to the 'new' allele Kpc postulated in a Japanese family is the low frequency antigen Levay recognized in England 33 years ago.

Four Kp(a-b-) Japanese sisters, the product of a consanguineous mating, have otherwise normal Kell antigens. Kpc, a 'new' allele of Kpa and Kpb is the most probable background.

A novel method is described for the production of saline-reacting antibodies from "incomplete' blood grouping sera. IgG anti-D is combined to protein A-bearing Staphylococcus aureus (SA), forming a polyvalent anti-D assembly. The SA-anti-D has a high titre in saline and is stable on 4 degrees C storage and lyophilisation. The material was successful in Rh(D) typing cells sensitised in vitro with various antibodies. Saline-reacting SA-anti-Kell and SA-anti-C were also produced.

A new high-frequency antigen related to the Kell system was defined by the serum of a patient, Mrs. Sub. The antigen was lacking from her cells and those of one of her three siblings. All random cells tested were incompatible with her serum as were bloods of other various "null" phenotypes, but Ko bloods were compatible suggesting that the antibody, subsequently called anti-K19, was related to the Kell blood group system.