Genetic polymorphisms in southwest Alaskan Eskimos

Allele frequencies of 28 genetic loci were determined in subsets (n ranged from 52 to 698) of a sample of Yupik-speaking Eskimos from southwestern Alaska. Five loci were monomorphic (Kell Kp (b+), ADA1, AK1, HBA, and PGDA). At the other loci, the most frequent alleles were AB00 (0.580), Fya (0.960), Jkb (0.513), Ms (0.333), CDe (0.591), ACPA (0.566), ESD1 (0.890), GLO2 (0.736), GPT1 (0.653), Hp2 (0.654), PGM1 (0.836), PGP1 (0.972), and UMPK1 (0.873). The most frequent immunoglobulin allotype Gm(1;21) occurred with a frequency of 0.829. The HLA alleles that occurred with highest frequencies were A24 (0.626), Bw48 (0.184), Cw3 (0.404), and DR4 (0.329). The average heterozygosity at all loci was 0.423. Based on the presence of the European allotype, Gm3;23;5,11,13, the proportion of European admixture in the Eskimo population was estimated to be 2.1%.

Epitope mapping of an HLA-B27 monoclonal antibody that also reacts with a 35-kD bacterial outer-membrane protein

Ye-3 is an HLA-B27-specific murine monoclonal antibody recognizing the heat-modifiable protein of Enterobacteriaceae. Here we used recombinant hybrid molecules between the HLA-B7 and HLA-B27 antigens to delineate the epitope recognized by Ye-3. Results of these experiments indicated that the segment of HLA-B*2705 spanning residues 77-81 was critical to the reactive epitope. It is known to be a major serological and functional recognition site of HLA-B*2705 and our data give support for its involvement also in the serological cross-reactivity with bacterial antigens.

Gene mapping in the idiopathic generalized epilepsies: juvenile myoclonic epilepsy, childhood absence epilepsy, epilepsy with grand mal seizures, and early childhood myoclonic epilepsy

Idiopathic generalized epilepsies, i.e., juvenile myoclonic epilepsy (JME), childhood absence epilepsy, and epilepsy with grand mal [generalized tonic-clonic seizures (GTCS)], are the most common genetic epilepsies. Linkage studies using Bf, HLA serologic, and DNA markers by three independent investigators, one from Los Angeles and two from Berlin, have localized the JME locus to the short arm of chromosome 6 (6p). Because members of the same JME family have the same JME phenotype of childhood absence epilepsy, epilepsy with grand mal (GTCS) seizures, or early childhood myoclonic epilepsy (ECME), our observations give evidence for a single-locus etiology in 6p for JME and for at least some of the childhood absence seizures, epilepsy with grand mal (GTCS) seizures, and ECME. Studies should now address whether locus heterogeneity exists within childhood absence epilepsy, epilepsy with grand mal (GTCS) seizures, or ECME. Markers linked to JME (Bf, HLA serologic, and DNA markers in the DQ region) can be used to resolve etiologic heterogeneity. Using such markers, both linked and unlinked forms of phenotypes that are clinically indistinguishable may be detected and provide evidence for etiologic heterogeneity. Studies should also concentrate on narrowing the JME locus to 2 to 3 cm by screening families with recombinant events using RFLPs, candidate genes, and new expressed sequences on chromosome 6.

Association of primary sclerosing cholangitis with HLA-DRw52a

We sought to determine whether there are specific HLA haplotypes in patients with either primary sclerosing cholangitis or primary biliary cirrhosis. Surprisingly, 100 percent of the 29 patients with primary sclerosing cholangitis had the HLA-DRw52a antigen, which is normally present in 35 percent of the population (relative risk, 109.5; P less than 0.00001). Fifteen of these patients had a single common haplotype: A1,B8,Cw7,DRw17,DQw2,DRw52a. In the remaining 17 patients there was a loss of at least one of these antigens. Of the 15 patients with the common haplotype, 12 also had ulcerative colitis, thereby linking the occurrence of ulcerative colitis in patients with primary sclerosing cholangitis to the presence of this haplotype. Although there was no association in 35 patients between primary biliary cirrhosis and specific HLA haplotypes, there was a significant association of the disease with DRw8 (relative risk, 3.1; P = 0.02). We conclude that the development of primary sclerosing cholangitis involves a strong genetic predisposition. Since the association of primary sclerosing cholangitis with HLA-DRw52a appears to be total, HLA typing should be helpful in differentiating this disease from primary biliary cirrhosis.

A combination of HLA-DQ beta Asp57-negative and HLA DQ alpha Arg52 confers susceptibility to insulin-dependent diabetes mellitus

Family and population studies indicate that predisposition to insulin-dependent (type I) diabetes mellitus (IDDM) is polygenic. It has been shown that the absence of the aspartic acid in position 57 (Asp57) of the DQ beta chain is positively correlated to IDDM. However, Asp57-negative haplotypes do not always confer susceptibility and conversely, some Asp57-positive haplotypes seem to be disease associated. It has been suggested that other HLA class II sequences, probably belonging to the HLA DQA1 gene, confer susceptibility to IDDM. This report, based on extensive oligonucleotide dot blot hybridization of PCR-amplified DQA1 and DQB1 genes, reinforces the importance of the Asp57-negative DQ beta chain, but also introduces the possibility that a DQ alpha chain bearing an arginine in position 52 (Arg52) confers susceptibility to IDDM. A molecular model of susceptibility to IDDM is proposed. This model strongly suggests that the disease susceptibility correlates quantitatively with the expression at the cell surface of a heterodimer, composed of a DQ alpha-chain bearing an Arg52 and a DQ beta chain lacking an Asp57. In view of the respective positions of the two residues and their charge, we might anticipate that both residues DQ beta Asp57 and DQ alpha Arg52 are critical for modulation of susceptibility, presumably via viral-antigenic peptide and/or autoantigen presentation.

Mapping the gene for juvenile myoclonic epilepsy

The practice of epileptology at a molecular level, where gene products are identified by gene mapping, will soon be possible for a growing number of epilepsies. Juvenile myoclonic epilepsy (JME) is the first of such epilepsies to be mapped to a chromosome, namely chromosome 6p21.3. Family studies of 68 JME probands from California revealed 50% of all families reported seizures in first- or second-degree relatives. Twelve percent of all family members other than the proband had epileptic seizures. Eighty percent of symptomatic siblings and 6% of asymptomatic siblings had diffuse 4- to 6-Hz multispike-wave complexes. Twelve percent of asymptomatic parents had diffuse, nonspecific slow waves mixed with spikes or sharp waves. JME is tightly linked to the Bf-HLA loci in chromosome 6. No matter what mode of inheritance is assumed, linkage to the clinical manifestations of JME and its associated EEG traits is indicated by lod scores over 3.0, as long as "EEG affected" but clinically asymptomatic family members are counted as affected during LIPED analysis. Studies are now being done to further localize the JME site. At the same time, further linkage studies should decide if JME is heterogeneous within itself and whether the same JME site in 6p21.3 underlies absence and grand mal epilepsies.

Diagnostic value of insulin-like growth factor-I in short stature

For the present, to determine growth hormone(GH) deficiency in patients with short stature, many provocative tests using various pharmacological agents such as glucagon, insulin, clonidine, arginine, growth hormone releasing factor, etc. should be done. These are not only complicated but are also misleading in some patients. In search of a simple and accurate method of detecting GH deficiency that may replace the more complicated provocative tests, we measured basal plasma insulin-like growth factor-I (IGF-I) to see the correlation with the peak GH values in the GH stimulation test. But, in each group of patients with different types of short stature, IGF-I values were poorly correlated. In addition, IGF-I values of the patients with short stature compared to the age- and sex-matched normal ranges showed a significant overlap, and the difference between the proportion of patients with subnormal values in GH deficient patients and non-GH deficient patients was not prominent. Nevertheless, in response to human growth hormone (hGH) administration, both the yearly growth rate and IGF-I levels increased conspicuously. Therefore, even though it may not be feasible to use IGF-I as a single diagnostic measure of patients with short stature, the change in IGF-I values in the follow up of hGH therapy may well represent the response to hGH.

[The prevalence of head louse infestation among urban and rural children in Korea]

The prevalence of head louse (Pediculus hamanus var. capitis) infestation in preschool and school children in 9 urban and 8 rural areas of Korea, was investigated. Of 11,865 children who were examined for head lice and nits, 2,900(24.4%) were found infested. The over-all infestation rate of rural children, 58.9%, was higher than that of urban children, 14.4%. There also existed significant differences in the infestation rate among various regions of urban as well as rural areas. Females were more infested than males. But there was no differences in infestation rate in either sex of preschool age. The infestation rate increased gradually from the age of 6, reached a plateau between 9-12 years of age and thereafter slowly decreased. The infestation rate of an orphanage children was higher than that of general childhood population. Health education and mass-delousing attempt are urgently required to lower such a high prevalence of head louse infestation in Korea.

An association between acute retinal necrosis syndrome and HLA-DQw7 and phenotype Bw62, DR4

Human leukocyte antigen (HLA) typing was performed on 27 white patients with acute retinal necrosis syndrome. Antigens for the HLA-A, -B, -C, -DR and -DQ loci were determined, and frequencies were compared with racially matched controls. There was a statistically significant increase in the frequency of HLA-DQw7 (11 of 20 [55%] of patients vs 294 of 1546 [19%] of controls, P = .0004, relative risk 5.20) that remained significant at the P = .05 level when the P value was multiplied by the number of antigens tested. The HLA phenotype Bw62, DR4 is also more frequent than in normal control populations (4 of 25 [16%] of patients vs 26 of 1023 [2.6%] of controls, relative risk 7.49). These results support an association between the acute retinal necrosis syndrome and certain HLA specificities and suggest a possible immunogenetic predisposition to the syndrome in some patients.

Human breast-milk factors influencing lipid metabolism by fetal rabbit aorta in organ culture

Effects of human or rabbit milk on cholesterol content, incorporation of [14C]oleate, and DNA synthesis were investigated in organ cultures of aorta from fetal and suckling rabbits. Human skim milk (50 mL/L) in organ culture decreased content (mumol/g protein) of aortic total cholesterol (control: 162.9 +/- 24.6 milk: 117.6 +/- 4.9) with significant decrease in cholesteryl esters (control: 16.5 +/- 5.1, milk: 2.3 +/- 0.5). The effect was observed in lipoprotein (total cholesterol: 120.2 +/- 8.8) and lipoprotein-free (total cholesterol: 85.4 +/- 5.1) fractions with molecular weight greater than 100,000. The human milk fraction with molecular weight greater than 100,000 was also the most active in promoting [3H]thymidine incorporation into DNA in fetal aorta. Although milk stimulated the incorporation of [14C] oleate into triglycerides (control: 38.8 +/- 2.5%, milk: 82.1 +/- 4.2%), decreased incorporation to phospholipids (control: 55.0 +/- 3.0%, milk: 11.3 +/- 1.8%) was observed. These studies suggest that milk contains factors influencing aortic lipid metabolism during development.

Juvenile myoclonic epilepsy (JME) may be linked to the BF and HLA loci on human chromosome 6

Although certain forms of epilepsy have long been suspected to be inherited, heterogeneity has made it difficult to find the genes responsible for any subtypes. We found that families ascertained through patients with juvenile myoclonic epilepsy show linkage with the BF and HLA loci on human chromosome 6. There is some evidence that the locus may be outside the HLA complex and no evidence as yet of an association with any allele of the HLA complex.

Anti-HLA-B7,B27,Bw42,Bw54,Bw55,Bw56, Bw67,Bw73 monoclonal antibodies: specificity, idiotypes, and application for a double determinant immunoassay

The monoclonal antibodies (MoAbs) KS3 and KS4 are secreted by hybridomas constructed with splenocytes from a BALB/c mouse sequentially immunized with the cultured lymphoid cells JKu and LG-2 which share only the HLA-B27 specificity. Serologic and immunochemical assays have shown that the two MoAbs recognize the same (or spatially close) determinant expressed by HLA-B7,B27,Bw42,Bw54,Bw55,Bw56,Bw67, and Bw73 alloantigens. This determinant is spatially close but distinct from those defined by the anti HLA-B27 monoclonal antibodies described in the literature. The syngeneic antiidiotypic MoAb T12-105 and T12-211 elicited with MoAb KS4 were shown to recognize idiotopes within the antigen combining site of MoAb KS3 and KS4. Neither idiotope was detected on the anti HLA class I and anti HLA class II monoclonal antibodies tested. The MoAb KS4 in combination with the anti human beta 2-microglobulin MoAb NAMB-1 was utilized to develop a double determinant immunoassay (DDIA). The latter represents a sensitive method to detect and quantitate HLA-B27 antigens in spent culture medium of lymphoid cell lines and in serum. Typing for HLA-B27 antigens with the DDIA of sera from HLA typed donors yielded results highly correlated with those of the conventional lymphocytotoxicity assay.

Evidence for the presence of low density and very low density lipoproteins in human amniotic fluid

Previous analysis of amniotic fluid (AF) noted only the presence of high density lipoprotein (HDL). In this study AF lipoprotein profile was examined using gel filtration column chromatography and Ouchterlony gel diffusion. Unlike previous studies which showed only the presence of HDL, we found significant amounts of low density lipoprotein (LDL) and very low density lipoprotein (VLDL). AF-LDL and AF-VLDL were identified by reactions with anti-h-apolipoprotein AI and AII antiserum and anti-h-apolipoprotein B-antiserum, respectively. Furthermore, bulk of the cholesterol mass was carried in VLDL (53.6 +/- 7.7%) and LDL (32.5 +/- 4.3%) with minor amounts (13.9 +/- 1.3%) in HDL fraction. It is concluded that human AF contains all three lipoproteins with most of the cholesterol being carried in very low density lipoprotein fraction.

A Yersinia pseudotuberculosis protein which cross-reacts with HLA-B27

The most-debated question in the investigation of the spondyloarthropathies has been whether there is molecular mimicry between host HLA-B27 antigens and the arthritis-causing pathogens. We have generated a monoclonal anti-HLA-B27 antibody in our laboratory and have used a radioimmunoassay to screen a panel of bacterial species. Two strains of Yersinia pseudotuberculosis were found to be highly reactive. The cross-reactive Yersinia component was identified by Western blot to be a 19,000 component. A preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis chromatography apparatus was constructed to isolate milligram quantities of this component. To verify that the component carried the HLA-B27-specific epitope, rabbits were hyperimmunized with the purified materials. Affinity-purified antibodies from one of the immunized rabbits indeed carried anti-HLA-B27 activity. Last, antibodies generated against synthetic peptides derived from the HLA-B27.1 amino acid sequence were tested against the Yersinia component. Positive reactivity was found with antibodies generated against a peptide spanning residues 69-83 of the HLA-B27.1 protein. Since this resides in the segment responsible for the allotypic specificity of the antigen, these experiments establish the presence of molecular mimicry to a high degree of confidence.

A Yersinia pseudotuberculosis protein which cross-reacts with HLA-B27

The most-debated question in the investigation of the spondyloarthropathies has been whether there is molecular mimicry between host HLA-B27 antigens and the arthritis-causing pathogens. We have generated a monoclonal anti-HLA-B27 antibody in our laboratory and have used a radioimmunoassay to screen a panel of bacterial species. Two strains of Yersinia pseudotuberculosis were found to be highly reactive. The cross-reactive Yersinia component was identified by Western blot to be a 19,000 component. A preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis chromatography apparatus was constructed to isolate milligram quantities of this component. To verify that the component carried the HLA-B27-specific epitope, rabbits were hyperimmunized with the purified materials. Affinity-purified antibodies from one of the immunized rabbits indeed carried anti-HLA-B27 activity. Last, antibodies generated against synthetic peptides derived from the HLA-B27.1 amino acid sequence were tested against the Yersinia component. Positive reactivity was found with antibodies generated against a peptide spanning residues 69-83 of the HLA-B27.1 protein. Since this resides in the segment responsible for the allotypic specificity of the antigen, these experiments establish the presence of molecular mimicry to a high degree of confidence.

Study of the components of reverse cholesterol transport in lecithin:cholesterol acyltransferase deficiency

Enzymatic and lipid transfer reactions involved in reverse cholesterol transport were studied in healthy and lecithin:cholesterol acyltransferase (LCAT), deficient subjects. Fasting plasma samples obtained from each individual were labeled with [3H]cholesterol and subsequently fractionated by gel chromatography. The radioactivity patterns obtained corresponded to the elution volumes of the three major ultracentrifugally isolated lipoprotein classes (very low density lipoproteins (VLDL), low density lipoproteins (LDL), and high density lipoproteins (HDL)). In healthy subjects, the LCAT activity was consistently found in association with the higher molecular weight portion of HDL. Similar observations were made when exogenous purified LCAT was added to the LCAT-deficient plasma prior to chromatography. Incubation of the plasma samples at 37 degrees C resulted in significant reduction of unesterified cholesterol (FC) and an increase in esterified cholesterol (CE). Comparison of the data of FC and CE mass measurements of the lipoprotein fractions from normal and LCAT-deficient plasma indicates that: (i) In normal plasma, most of the FC for the LCAT reaction originates from LDL even when large amounts of FC are available from VLDL. (ii) The LCAT reaction takes place on the surface of HDL. (iii) The product of the LCAT reaction (CE) may be transferred to either VLDL or LDL although VLDL appears to be the preferred acceptor when present in sufficient amounts. (iv) CE transfer from HDL to lower density lipoproteins is at least partially impaired in LCAT-deficient patients. Additional studies using triglyceride-rich lipoproteins indicated that neither the capacity to accept CE from HDL nor the lower CE transfer activity were responsible for the decreased amount of CE transferred to VLDL and chylomicrons in LCAT-deficient plasma.

Serologic and biochemical analysis of HLA B15 and B5 complexes

Charge heterogeneity of HLA-B15 and HLA-B5 complexes was analyzed by one-dimensional isoelectric focusing (1D-IEF). Frozen peripheral blood lymphocytes were metabolically labeled with 35S methionine. The class I antigens were immunoprecipitated with monoclonal antibody 4E, which detects a determinant shared by HLA-B locus and Aw19-complex antigens. The desialated 1D-IEF banding patterns were correlated to microcytotoxicity data of a panel of donors from a variety of racial groups. Serologic analysis indicated the presence of specific variants: Te76, Te78, and Te79. 1D-IEF analysis clearly showed polymorphism in the B15 and B5 complexes. The Bw62 associated variant Te79 exhibited bands distinct from Bw62. One Bw62 typed donor produced a band that was different from other Bw62 typed cells. A migration pattern difference was discovered between blacks and Caucasians that were typed Bw57. Investigated antigens included HLA-B35, w46, 51, w52, w53, w57, w58, w62, w63, w70, Te76, Te78, and Te79.

Genetic factors in Haemophilus influenzae type b disease susceptibility and antibody acquisition

Because Alaskan Eskimos have the greatest known endemic risk of Haemophilus influenzae type b (Hib) disease and represent a comparatively homogeneous population, we selected this population to evaluate the presence or absence of an association of 35 genetic markers (alleles or allotypes) at 12 chromosomal loci with susceptibility to both invasive Hib disease risk and level of Hib anticapsular antibody. We studied nearly all Alaskan Eskimo children who had had invasive Hib disease between 1971 and 1982 in southwestern Alaska (n = 103) and an equivalent number of controls matched for age, race, and village of residence, and verified not to have had proved or suspected Hib disease. We found no significant associations with Hib disease for the single alleles of HLA-A, -B, -C, -DR, Gm, Km, Am, Kidd, MNSs, ABO, esterase D, or glutamate pyruvate transaminase loci. However, we observed a significant interaction of two loci, Gm(a;..;g,s,t) allotype and HLA-DR8 (P = 0.002), with increased Hib disease susceptibility, and an interaction of the same Gm allotype and HLA-DR5 with decreased disease susceptibility (P = 0.01). We also compared the level of anticapsular antibody to Hib with each genetic marker and two-locus interactions, but no genetic association with antibody level was found. We conclude that some genetic factors contribute to the susceptibility to invasive Hib disease in this population.

Effects of dietary animal and plant proteins on the cholesterol metabolism in immature and mature rats

Three- and 9-mo-old rats were fed purified diets that contained either casein, cottonseed or soybean protein for 28 d, and plasma total and high density lipoprotein (HDL) cholesterol, lecithin cholesterol acyltransferase (LCAT) activity and excretion of fecal neutral sterols were measured. These analyses were performed in order to examine how various dietary proteins from animal and plant sources fed in a purified diet influence the changes in the cholesterol metabolism of the young and old rats. Both immature (3-mo-old) and mature (9-mo-old) rats fed purified diet containing casein maintained significantly higher plasma total and HDL cholesterol levels than their counterparts fed the same diets but containing plant proteins (soybean and cottonseed). The fractional rate of esterification (FR) of plasma free cholesterol in mature casein-fed rats was lower than that in immature rats. The FR was also lower in immature rats fed casein than in those fed plant protein. The net turnover rate (NR) of plasma cholesteryl esters (CE) tended to be higher in mature rats and in general was not affected by the dietary protein source. The rate of fecal excretion of neutral sterols was significantly higher in immature rats than in mature rats and in animals fed plant proteins at both ages than in those fed casein.

Bronchioloalveolar carcinoma in progressive systemic sclerosis

Bronchioloalveolar carcinoma(BAC) is the most common histological type of lung cancer arising in an area of scar tissue, and it is frequently superimposed in the fibrotic lung of progressive systemic sclerosis(PSS). The so called scar cancer is believed to be caused by the transformation of hyperplastic epithelium to metaplasia and finally to neoplasia under the conditions of chronic inflammation with some unknown etiological factors. The authors report a case of BAC in a woman with the typical picture of PSS.

Ye-1, a monoclonal antibody that cross-reacts with HLA-B27 lymphoblastoid cell lines and an arthritis causing bacteria

A monoclonal antibody, Ye-1, was generated by immunizing BALB/c mice with Yersinia enterocolitica. This antibody also reacted with all of 12 B27 positive lymphoblastoid cell lines, but only four of 31 B27 negative ones. Three of the four reactive B27 negative cell lines were B7 positive. A B27 positive cell line which has lost the B27 expression because of experimentally-induced mutation became unreactive with the Ye-1. These findings support the possibility that there is cross-reactivity between HLA-B27 antigens and Y. enterocolitica.

Absence of lymphotoxic antibodies in patients with Yersinia-induced arthritis, Reiter's syndrome and ankylosing spondylitis

Serum samples from patients with Reiter's syndrome, ankylosing spondylitis, Yersinia-induced arthritis and Yersinia infections not followed by arthritis were collected and assayed for complement-dependent cytotoxicity, using a standard dye-exclusion microcytotoxicity technique. A total of eighty-nine serum samples derived from these patients were compared to those of forty control subjects, using as target cells six different cultured cell line cells and peripheral blood mononuclear cells isolated from the blood samples of four subjects. Serum samples from only five of the subjects demonstrated cytotoxicity. This did not depend on whether the target cells were HLA-B27 or not. Hence, if antilymphocytic auto-antibodies are present in these patients, they will require a different technique for their detection.

Detection of Lewis a antigenic determinants in Chinese medicinal herbs

Two Chinese medicinal herbs, Leonurus sibiricus L. and Carthamus tinctorius L., were found to have high levels of Lewis a (Lea)-like determinants. The water-soluble extracts specifically inhibited hemagglutination, hemolysis, and lymphocyte cytotoxicity directed against Lea. They did not inhibit Leb nor other specificities detected on lymphocytes, resulting from the interaction of Lewis, Secretor, and ABO systems such as A1Leb and A1Led. The activity was nondialyzable, resistant to boiling and proteolytic enzymes, but was destroyed by periodate. It was suprising that an Lea substance, previously found in human secretions, was also present in flower abstracts.