Cross-reactions in the HLA system revealed by red blood cells expressing HLA determinants, with particular reference to cross-reaction between HLA-A2 and B17

Sera with cytotoxic and haemagglutinating activity towards HLA-A2/28 were also shown to react with red blood cells (RBC) expressing the HLA-B17 antigen determinant. Absorption procedures with white blood cells (WBC) indicated that this was due to an HLA-A2/B17 cross-reaction. Absorption experiments with some other sera which previously had shown cytotoxic and haemagglutinating activity towards different HLA specificities, revealed broad cross-reaction related to HLA-B locus antigens.

Association between HLA-B40 and acute alcoholic hepatitis with cirrhosis and the lack of relation between carcinoembryonic antigen and HLA antigens in alcoholic liver disease

The frequency of HLA-B40 was significantly increased in 30 patients with acute alcoholic hepatitis with cirrhosis (63%) and in 60 patients with alcoholic cirrhosis with or without acute alcoholic hepatitis (48%) compared with its frequency in 234 healthy blood donors (18%). The HLA-B40 frequency was not increased in 20 patients with acute alcoholic hepatitis without cirrhosis (0%), in 41 patients with fatty liver infiltration (12%), or in 67 alcoholics with moderate biochemical abnormalities (19%). The association between HLA-B40 and alcoholic liver cirrhosis and acute alcoholic hepatitis with cirrhosis favors the idea that these disorders might be genetically determined. There was, however, no difference in the distribution of the HLA antigens in 54 patients with different degrees of alcoholic liver disease and an elevated carcinoembryonic antigen (CEA) value of greater than or equal to 5.0 micrograms/l compared with 61 alcoholics with different degrees of liver disease and a normal CEA value. Thus, the results of HLA-A and -B typing gave no evidence of genetic susceptibility to develop a CEA elevation in patients with alcoholic liver disease.

Differential coating of human red blood cells with C4 or C3 in a low ionic strength medium

An EDTA-containing, low ionic strength medium, pH 5.1, can be used for incubation of blood to obtain coating of red blood cells with C4 or C3. The coating achieved depends on incubation temperature (4 or 37 degrees C) and on whether or not CaCl2 or MgCl2 is added to the medium. The optimal concentration of EDTA appears to be 2 mM under the present conditions. This is equimolar to the final concentration of the added CaCl/MgCl2. The choice between CaCl and MgCl2 depends on whether blood without anticoagulant or ACD blood is employed. Coated cells keep satisfactorily for 5 weeks at 4 degrees C in Alsever's solution as well as after freezing and thawing. C3-coated cells can be converted to C3d-coated ones by incubation in normal, compatible, EDTA-containing serum at 37 degrees C.

Association between the electrophoretically-determined C4M haplotype product and partial inhibition of anti-Cha

C4-coated Ch(a+) red blood cells (RBC) were used as indicator cells in a serum inhibition reaction of anti-Ch(a), for the determination of the Ch group of serum. This serological study, combined with electrophoretic studies of C4 in a family material, showed that the C4M haplotype product was associated with partial inhibition of anti-Ch(a).

The HLA system in primary open angle glaucoma and in patients with pseudoexfoliation of the lens capsule (exfoliation or fibrillopathia epitheliocapsularis)

HLA typing of eighteen antigens in 43 patients with pseudoexfoliation of the lens capsule, 45 patients with capsular glaucoma, and 43 patients with primary open angle glaucoma was performed. No significant deviation from a control series of 45 subjects was found.

HLA antigens in alcoholics, with special reference to alcoholic cirrhosis

HLA antigen determination showed that the frequency of HLA-B40 was significantly increased (49%) in 43 patients with alcoholic cirrhosis, compared with the frequency found in 234 healthy blood donors (18%). The HLA-B40 frequency was not increased in three other patient groups: 36 patients with alcoholic liver disease without cirrhosis (14%), 21 patients with miscellaneous liver disease (24%), and 26 alcoholics without liver disease (24%). We could not confirm the previously reported association between advanced alcoholic liver damage and HLA-B8, which has been taken as support for the relation to autoimmune mechanisms. The association with HLA-B40, however, favours the idea that genetically determined individual susceptibility to alcoholic liver cirrhosis may exist.

HLA antigens on red blood cells. Two donors with extraordinarily strong reactivity

We have shown exceptionally strong HLA reactivity of the red blood cells (RBC) of two healthy blood donors, concerning several HLA antigens. HLA antigens not usually detectable on RBC are also expressed on the RBC of these donors. The RBC show a broad spectrum of reactivity with sera containing HLA antibodies. Absorption/elution experiments with these RBC and HLA antisera proved successful. Absorption studies with leucocytes showed that HLA-A2 and A28 behaved as separate specificities also on RBC, even though antisera always seem to contain heamagglutinins that react with both specificities. We found no evidence that HLA is associated with beta2-microglobulin on the RBC membrane.

Survival studies of 51Cr Ch(a+) red blood cells in a patient with anti-Cha, and massive transfusion of incompatible blood

Survival studies of 51Cr, Ch(a+) red blood cells in a patient with anti-Cha, showed normal survival time in the observation period of 6 days. Successive massive transfusion of Ch(a+) blood was performed without any complication. A very strong secondary immune response to the Ch antigen was observed.

Chido, Rodgers and C4. In vivo and in vitro coating of red blood cells, grouping and antibody detection

C4 sucrose/low ionic strength (LIS)-coated red blood cells (RBC) are excellent for the detection of the previously 'nebulous' antibodies, anti-Chido and anti-Rodgers, as well as for serum/plasma typing of these antigens by an inhibition technique. By enzyme treatment of such cells, it is confirmed that the Ch and Rg antigens reside on the C4d part of the C4 molecule. Freshly taken RBC from normal individuals were examined with a sensitive Auto-Analyzer technique with anti-Chido, anti-C4 and anti-C3 sera. All normal RBC were shown to have C4d and C3d components on their surface. The technique was also very sensitive for the detection of the Ch antigen, which was detected on the RBC of all Chido-positive individuals, and which did not show great variation in strength by this method. The mode of in vivo C4 fixation on normal RBC seems to be different from the fixation in LIS or by RBC antibody-mediated activation.

Association between HLA and red cell antigens. VII. Survival studies of incompatible red blood cells in a patient with HLA-associated haemagglutinins

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.

Association between HLA and red cell antigens. V. A further study of the nature and behaviour of the HLA antigens on red blood cells and their corresponding haemagglutinins

The variation in the reactivity of red blood cells (RBC) with HLA haemagglutinins was studied, and the influence of some variable factors evaluated. A comparison of the HLA reactivity of RBC with automated and manual methods, showed the superiority of the Auto-Analyzer technique. The similarity in the nature and behaviour of HLA RBC antigens and the related Chido and Rg antigens is discussed. Inhibition/adsorption experiments were performed, and the results did not support the theory that HLA antigens on RBC originate from serum-HLA-active substance. The strength of the HLA reactivity of RBC from a donor was shown to vary from time to time without evidence of clinical disease.

Association between HLA and red cell antigens. VI. Family studies

The reactivity of the HLA antigens A28, B7 and B8 on red blood cells (RBC) has been studied, and the inheritance of the strength of reactivity examined in 13 families where the HLA haplotypes could be determined. Examination of individuals possessing more than one of the three antigens showed that the antigens seemed to be expressed independently of each other on RBC. The family studies showed that the HLA reactivity of RBC does not invariably follow the HLA haplotype determining the particular antigen. It was also shown that heterozygosity/homozygosity did not seem to have much influence on the strength of reactivity. Our conclusion is that several factors are likely to be responsible for the great variation in HLA reactivity of RBC.