Bruce Chown

The Slanted Capillary Method of Rhesus Blood-grouping

In 1944 a method of Rh blood-grouping, using slanted capillary tubes, was described (Chown, 1944). Further experience with the method led to the appreciation of certain errors in it, which, in 1946, we pointed out, together with ways of preventing them (Chown and Lewis, 1946). Although Discombe and Meyer (1948) reported favourably on the revised method, descriptions of the original one remained more readily available in Britain (Mollison, Mourant, and Race, 1948; Pickles, 1949; Poole and Williams, 1951), so that, because of the inherent errors in this form, the method in any form fell into disrepute. We have used the revised method on many thousands of blood samples, and believe that, properly carried out, it is simple, rapid, accurate, and economical for Rh-grouping. The slanted capillary has further advantages and uses which we shall report on later.

Some Blood Group Frequencies in a Caucasian Population

The data here recorded have been gathered over the past year or so; they are the results of tests on unrelated “normal” adult Caucasian Manitobans. There has been no selection which might be expected to alter distribution. The Lutheran, Kell and Kidd systems. For the Lutheran system all samples were tested with anti-Lua (Scrog/8) and anti-Lub (Sav/8) by the saline capillary method. The serum Scrog contains an antibody of the Bennett-Goodspeed family (RACE and SANGER [4]). Th‘ is was eliminated by absorbing Scrog on known Lu(a +) Bennett-Goodspeed-negative cells and then eluting. The eluate was used to check all Scrog-positive samples. The single example of Lu(b-) was checked by the indirect Coombs method. We do not know of any other large series tested with both anti-Lua and anti-Lub. The data in Table 1 agree with expectation while the calculated gene and genotype frequencies do not differ significantly from those calculated by RACE and SANGER [4] based on tests with anti-Lu*. For the Kell system all samples were tested with anti-K (Nash), anti-k (D/16), anti-Kpa (McM) and anti-Kpb (Raut/4) by the papain capillary method. Anti-Kpb (Raut) contains a weak anti-K but in the 1 : 4 dilution in which it was used it does not react more weakly with K + than with Kcells. Some, but not all, of the K + samples were checked with anti-Kpb (Brat) by the indirect Coombs method: antiKpb (Brat) is thought not to contain anti-K. The data in Table I agree with expectation while the gene and genotype frequencies are in close agreement with those calculated by ALLEN, LEWIS and FUDENBERG [l]. For the Kidd system the indirect Coombs capillary method was used, each sample being tested with anti-Jkb (Kni/8) and one of two

The Bennett-Goodspeed antigen or antigens.

Many sera used in blood grouping contain a second antibody. Not infrequently this belongs to what appears to be a family of antibodies called variously anti‐Donna, anti‐Sturgeon, anti‐Ho, anti‐Bennett‐Goodspeed, anti‐Price, etc. The reactions with the sera are not always reproducible. The antigen was found in 7 out of 158 unrelated parents. In 5 of 72 negative x negative matings one child or more was positive.

On the Antigen Goa and the Rh System1

Summary. A study, primarily based on two negro families in which the propositae were D‐positive and had produced ‘anti‐D’, make it certain that the antigen called Goa (Gonzales) is part of the D complex of the Rh system and that it is characteristic of those people who make up Category IV of Tippett and Sanger.

The Rh Antigen Dw (Wiel)

Evidence is brought forward confirming that the antigen “Wiel” (Transfusion 2: 150, 1962) is part of the D segment of the Rh system; is rare in Whites (none in 13,000) but not uncommon in Negroes (9 positive in 253). Its name is changed to Dw, Rh(23) or rhwo, the common genes designated ***Dwe or Rwo, CDwe or Rwo1 and cDwE or Rwo2, and a table of phenotypes and genotypes given. When Dw is not partnered with D it reacts as a Du; its specific nature is recognized by reaction with anti‐Dw.

The inheritance of the Kell blood groups in a Caucasian population sample.

In 1963 we published Kell blood group frequencies for 1277 unrelated adult Caucasians living in Manitoba whose red cells had been tested with anti-K(Nash), anti-k(D/16), anti-Kpa(McM) and antiKpb(Raut/4) by the papain capillary method [CHOWN et al., 11. The present report deals with the frequency and inheritance of the Kell genes in another sample drawn from the same population: 900 unrelated couples and their 2599 children. For this study the same sera and methods were employed as those in the 1963 study save that the anti-Kpb(Raut/4) was used by the capillary indirect Coombs method. Ascertainment. The ascertainment for the first 700 of the present 900 families has been given [CHOWN et al., 21; the frequency distribution of the different categories in the remaining 200 is approximately the same as for the 700: there are now 322 families with one child or more with mongolism. It might be thought that inclusion of these 322 families would distort our figures, because EVANS et al. [3] found ‘a significant excess of Kell-positive mongols’ in a sample made up of 82 mongol-sib pairs and their parents a t Liverpool, England and 82 mongol-sib pairs at Buffalo, New York. However, EVANS et al. [4] have re-examined this question using 257 of our 322 families and 190 English families: in this sample there was no excess of Kell positive mongols. There is therefore no evident reason why these 322 families should not be considered as ‘random’ for the purpose of the present study.

Low Protein Rh Immune Globulin (Rh IgG)

Abstract. After 16–32 months in solution at 4°C, ultracentrifuge and immunoelectrophoresis assays of five lots of low protein Rh IgG protein concentrations 3.9, 5.8, 4.1, 3.4 and 3.1%, revealed each lot to consist of a single unaggregated and unfragmented protein with an s20w constant of 6.5–7.3. The lots were 94.0–98.5% pure IgG. Autoanalyzer studies demonstrated no loss of anti‐D for 16–37 months except in one lot stable at 20 months which showed a drop from 363 to 298 μg/ml at 26 months. 125I antiglobulin measurements revealed a 23‐ to 40‐percent early loss of anti‐D with stability thereafter. Low protein Rh IgG cleared Rh‐positive cells from 11 Rh‐negative volunteers and protected 2,093 Rh‐negative women at risk of Rh immunization at least as effectively as standard Rh IgG. Low protein Rh IgG is a pure, stable, active, protective and economical agent for use in Rh prophylaxis.

AN ERROR IN RH TESTING IN PREGNANCY

Anti-D (anti-Rho) in the blood of two Rh-negative pregnant women was believed to be due to active immunization. In the first case, however, antibodies were no longer detectable 2 weeks later. In the second case they disappeared by the end of 31 weeks. It was discovered that both women had been given immune globulin (human) because of exposure to rubella. The globulin given to the first woman probably contained about 0.1 mug of anti-D per ml; that given to the second probably contained about 0.6 mug of anti-D per ml. Both babies were O Rh-positive. Both women were given Rh immune globulin after delivery. Both have completed a further pregnancy and no anti-D has been found on many tests. In tests carried out in 1971 all samples of immune globulin (human) examined contained anti-D, but usually in inconsequential trace amounts.