Progress in Rhesus Histocompatibility Typing Resulting from the Second International Nonhuman Primate Histocompatibility Workshop (1973)

The Second International Nonhuman Primate Histocompatibility Workshop permitted comparison of rhesus monkey alloantisera developd in various laboratories on a single common panel of related and unrelated monkeys. Analysis of the data permits the conclusion that at least nine specificities are recognized by more than one laboratory, including six at the first locus and three at the second locus.     

The Gm-Pi linkage heterogeneity in view of Pi M subtypes

In this study linkage between the loci for Gm (γ-type heavy-chain immunoglobulin markers) and Pi (α₁-antitrypsin/α₁-protease inhibitor) has been shown in families segregating for the Pi M subtypes (Ml, M2, M3 and Msal) as identified by separator isoelectric focusing. The estimate for the Gm-Pi (M-type) recombination is 0-29 (95% limits 0-24-O37) at a peak lod score of 4-31 and with no sex difference. This value is not significantly different from updated recombination frequency estimates for Gm-Pi in Pi MS (0-26) and Pi MZ, SZ and FZ families (0 21). The overall Gm-Pi recombination fraction estimate of 0 26 (95 % limits O23-0-30) at a peak lod score of 20-75 must now be considered as solid. There is a significant heterogeneity within the male Pi MZ families in that the new Finnish families show a higher recombination between Gm and Pi. There is also a possible segregation distortion (Z:M = 23:8). The heterogeneity is discussed in terms of haplotypes, the behaviour of which could be determined by linked genes or chromosomal rearrangements. The possibility that the α₁-antitrypsin level influences recombination frequency has not been ruled out, but cannot explain the heterogeneity within Pi MZ families.     

Ramification of the portal vein at the porta hepatis in humans

The ramification of the portal vein at the porta hepatis was studied by anatomic dissection performed in 32 formalin fixed human livers. In all the specimens there were branches which ran towards the caudate lobe, arising from the portal vein and either from the left or the right portal branches. Tri-and quadrifurcation of the portal vein was observed. In 5 cases (16%) there were branches arising from left portal branch or portal vein and directed anteriorly to the quadrate lobe or to the region of the gall-bladder sulcus. These branches ranged from 1.0 to 6.0 mm in diameter. The portal caudate branches were divided into 3 groups.Group 1: Branches to the papillary process; 1 or 2 branches in 26 cases (82%), 3 or 5 branches in 3 cases (9%) and no branches in 3 cases (9%);     

Inhibition of the Mixed Lymphocyte Culture Response by Antibody Following Successful Human Renal Transplantation

Immunoglobulin G, appearing after several months in the serum of a recipient of a successful kidney transplant from a closely matched sibling donor, was demonstrated to progressively inhibit unidirectional mixed lymphocyte cultures when donor lymphocytes were used either in responding or stimulating cell populations. The active recipient IgG had no effect in cultures in which donor cells were not used, nor did IgG obtained from other individuals show nonspecific inhibitory effects on cultures containing donor cells. It is suggested that the MLC inhibitory immunoglobulin may serve an immunoregulatory function after renal transplantation.     

Total serum IgD is increased in atopic subjects

We have developed a sandwich-type ELISA system for measuring total IgD levels in the serum of atopics and non-atopic controls. In this ELISA system, affinity purified goat anti-human IgD was used for capture. Results were superior to those obtained with monoclonal anti-human IgD antibody. No cross-reactivity could be demonstrated to IgG, IgM, IgA or IgE. The assay showed minimal non-specific binding even with initial serum dilutions of 1:2. The results obtained were reproducible among replicates (Mean CV +/- SEM = 0.03 +/- 0.002; n = 251), between dilutions (CV = 0.08 +/- 0.006; n = 108), and between assays (CV = 0.05 +/- 0.12; n = 5). We used routine radioimmunoassay for measuring total serum IgE. Using these assays total serum IgD and IgE levels were measured in 75 atopic patients and 33 normal subjects. None of the atopics had recent immunotherapy. As expected, the geometric mean serum IgE in atopics (373 ng/ml) was significantly higher than that in normal subjects (49 ng/ml) (P less than 0.01). However, geometric mean serum IgD was also significantly higher in atopics (20.3 micrograms/ml) than that in normal subjects (8.4 micrograms/ml) (P less than 0.02). In both atopic and normal groups, mean serum IgD level did not differ significantly on the bases of age, sex or asthmatic status. Furthermore, total serum IgD was not significantly correlated with total serum IgE (r = 0.14; P = 0.14; n = 108), indicating that immunoregulatory control of the basal levels of the two isotypes is not linked.(ABSTRACT TRUNCATED AT 250 WORDS)     

Mouse homologues of the human AZF candidate gene RBM are expressed in spermatogonia and spermatids, and map to a Y chromosome deletion interval associated with a high incidence of sperm abnormalities

An RNA-binding motif (RBM) gene family has been identified on the human Y chromosome that maps to the same deletion interval as the 'azoospermia factor' (AZF). We have identified the homologous gene family (Rbm) on the mouse Y with a view to investigating the proposal that this gene family plays a role in spermatogenesis. At least 25 and probably >50 copies of Rbm are present on the mouse Y chromosome short arm located between Sry and the centromere. As in the human, a role in spermatogenesis is indicated by a germ cell-specific pattern of expression in the testis, but there are distinct differences in the pattern of expression between the two species. Mice carrying the deletion Yd1, that maps to the proximal Y short arm, are female due to a position effect resulting in non-expression of Sry ; sex-reversing such mice with an Sry transgene produces males with a high incidence of abnormal sperm, making this the third deletion interval on the mouse Y that affects some aspect of spermatogenesis. Most of the copies of Rbm map to this deletion interval, and the Yd1males have markedly reduced Rbm expression, suggesting that RBM deficiency may be responsible for, or contribute to, the abnormal sperm development. In man, deletion of the functional copies of RBM is associated with meiotic arrest rather than sperm anomalies; however, the different effects of deletion are consistent with the differences in expression between the two species.