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J Bertrams

Publications and source records attributed to J Bertrams.

At least 37 records · Page 2Linked to original sources
PubMed1988

Genetic heterogeneity, modes of inheritance, and risk estimates for a joint study of Caucasians with insulin-dependent diabetes mellitus.

From 11 studies, a total of 1,792 Caucasian probands with insulin-dependent diabetes mellitus (IDDM) are analyzed. Antigen genotype frequencies in patients, transmission from affected parents to affected children, and the relative frequencies of HLA-DR3 and -DR4 homozygous patients all indicate that DR3 predisposes in a "recessive"-like and DR4 in a "dominant"-like or "intermediate" fashion, after allowing for the DR3/DR4 synergistic effect. Removal of DR3 and DR4 reveals an overall protective effect of DR2, predisposing effects of DR1 and DRw8, and a slight protective effect of DR5 and a predisposing effect of DRw6. Analysis of affected-parent-to-affected-child data indicates that a subset of DR2 may predispose. The non-DR3, non-DR4 antigens are not independently associated with DR3 and DR4; the largest effect is a deficiency of DR2, followed by excesses of DR1, DRw8, and DRw6, in DR4 individuals, as compared with DR3 individuals. HLA-B locus distributions on patient haplotypes indicate that only subsets of both DR3 and DR4 are predisposing. The presence or absence of Asp at position 57 of the DQ beta gene, recently implicated in IDDM predisposition, is not by itself sufficient to explain the inheritance of IDDM. At a minimum, the distinguishing features of the DR3-associated and DR4-associated predisposition remain to be identified at the molecular level. Risk estimates for sibs of probands are calculated based on an overall sibling risk of 6%; estimates for those sharing two, one, or zero haplotypes are 12.9%, 4.5%, and 1.8%, respectively. Risk estimates subdivided by the DR type of the proband are also calculated, the highest being 19.2% for sibs sharing two haplotypes with a DR3/DR4 proband.

Adolescent↗
PubMed1988

Association of Crohn's disease with HLA phenotype B44, Cw5.

Genetic influence on the development of Crohn's disease (CD) is commonly accepted. However, proof of definite genetic markers is still pending. Most investigations have focused on HLA antigens, and associations with HLA B12 and HLA A2 have been reported, but the design of these retrospective studies is open to criticism. We have undertaken a consecutive study of 96 patients with CD under well-defined conditions in order to test the hypothesis that CD is associated with particular HLA antigens. Our results identify a significant association of CD with the phenotype HLA B44,Cw5. But since a major proportion of the CD patients do not bear this phenotype, other predisposing genetic factors, which have not yet been defined, may exist in addition to environmental factors.

Adolescent↗
PubMed1988

HLA antigens in ankylosing spondylitis associated with Crohn's disease. Increased frequency of the HLA phenotype B27,B44.

In a consecutive case study 231 patients with Crohn's disease were investigated for ankylosing spondylitis (AS) and HLA-A, B, C, DR antigen association. Eighteen patients (7.8%) had definite AS according to the New York criteria; 13 (72%) were HLA-B27 positive. The phenotype B27,B44 was seen in 8 patients (44%) compared to only 3 (1%) of 300 controls (p less than 10(-7), and 1 (0.5%) of 213 patients with Crohn's disease without AS (p less than 10(-7). We conclude that patients with the phenotype B27,B44 are highly at risk (relative risk = 68.8) for the common manifestation of Crohn's disease and AS.

Adult↗
PubMed1986

HLA-DR effects in a large German IDDM dataset.

DR4 and DR3 are in strongest linkage disequilibrium with IDDM susceptibility genes, and DR1 demonstrates a lesser degree of positive disequilibrium. DR3/DR4 heterozygotes have the highest risk. The DR1 increase occurs almost exclusively in DR4/DR1 heterozygotes, suggesting that DR1 may be in disequilibrium with the same susceptibility gene as DR3. Homozygotes for DR4 and especially DR3 have a higher risk than heterozygotes of either with DRX. GLO-2 is increased in diabetic haplotypes carrying DR4, DR3 or DR1.

Alleles↗
PubMed1986

A new partially deficient variant in the phosphoglucomutase 1 system, PGM1*W31.

In a case of disputed paternity an inherited hyposynthetical variant of the PGM1*1A gene was identified. This variant could not be detected by conventional electrophoresis on cellulose acetate membranes but clearly appeared on polyacrylamide gels after isoelectric focusing. The enzyme activity of this variant was about 25% of the normal PGM1*1A protein. The variant was designated PGM1*W31.

Electrophoresis, Polyacrylamide Gel↗
PubMed1986

Islet cell antibodies and the development of diabetes mellitus in relation to mumps infection and mumps vaccination.

Islet cell antibodies were investigated in 127 non-diabetic children after mumps infection and in four out of seven children who developed diabetes mellitus shortly after active mumps vaccination. Twenty-one of the children who had mumps and all four vaccinated children who were tested had islet cell cytoplasmic antibodies. In contrast, islet cell surface antibodies were detected in 43 out of 68 patients with mumps infection and in 32 out of 44 patients with other viral diseases. All but one mumps-infected child and all the other viral infected patients investigated did not develop diabetes mellitus. The mumps-infected ICA positive children did not show those HLA-frequencies associated with Type 1 diabetes.

Antibodies↗
PubMed1986

Monozygotic triplets with Crohn's disease of the colon.

Female monozygotic triplets all developed Crohn's disease within a period of 11 mo. The monozygosity was demonstrated by analysis of 24 genetic markers of different chromosomal localization. Crohn's disease was diagnosed using clinical, radiologic, and endoscopic findings. Histologic evaluation of bowel tissue was consistent with Crohn's disease. All 3 patients had colon involvement; the terminal ileum appeared normal. The patient in whom Crohn's disease was first diagnosed had the severest course. Our observations support the role of a genetic influence in the manifestation of Crohn's disease. Nevertheless, environmental factors or microorganisms, or both, have to be taken into account, perhaps as factors promoting the outbreak of Crohn's disease.

Adult↗
PubMed1986

Homogeneity of HLA-DQ,DR phenotypes in lymphocyte subsets of normal individuals.

The study was performed to evaluate the association of HLA-DQ and DR antigens with the composition of peripheral blood lymphocytes. B cells, T cells, and T subsets were enumerated in 200 normal individuals by indirect immunofluorescence microscopy using the monoclonal antibodies OKT3, OKT4, OKT8, and OKIa1. Results were related to the HLA-DQ,DR phenotypes of the investigated population. No significant correlation between any of the lymphocyte subsets and of the HLA-DQ,DR antigens was found.

Antibodies, Monoclonal↗
PubMed1986

Proposal for the nomenclature of human plasminogen (PLG) polymorphism.

Since its discovery, human plasminogen (PLG) polymorphism has received widespread acceptance in population genetics and forensic haematology. Due to the large number of variant alleles described, a PLG reference typing and Plasminogen Symposium was held, at which a nomenclature proposal was inaugurated. The technology of comparing PLG variants was based on isoelectric focusing and subsequent detection by caseinolytic overlay and 'Western' blotting. Typing results permitted comparison of so far described variant designations and resulted in a new nomenclature proposal for PLG polymorphism. It is recommended that the two most common alleles found in all investigated races be called: PLG*A (previously also PLG*1) and PLG*B (previously also PLG*2), the known variants with acidic pI: PLG*A1 to *A3, intermediate variants: PLG*M1 to *M5, PLG*M5 being functionally inactive, and basic variants: PLG*B1 to *B3. For future classification of newly discovered variants, samples should be compared at any of the laboratories participating in the reference typing.

Collodion↗
PubMed1986

Human C81 (alpha-gamma) polymorphism: detection in the alpha-gamma subunit on SDS-PAGE, formal genetics and linkage relationship.

The molecular basis of human C81 (alpha-gamma) polymorphism could be elucidated by immunoprecipitation of human C81 allotypes and separation of the alpha-gamma and beta subunits on sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions. If the C8 molecules were completely reduced, C81 polymorphism was no longer detectable on SDS-PAGE. It is concluded that C81 variation depends on charge rather than molecular weight differences. Four C81 allotypes, the common A and B and two rare allotypes provisionally named A2 and B1, could be distinguished. The rare allotype A1 as detected by isoelectric focusing with subsequent C8 (alpha-gamma)-dependent functional overlay could no longer be visualized on SDS-PAGE. This allotype may therefore be elicited only in the intact C8 molecule. The beta-chain polymorphism named C82, probably also reflecting charge variation of the C8 molecule, could not be detected yet on SDS-PAGE. The distributions of C81 phenotypes and their respective allele frequencies were in good agreement with previously reported data. In the study of 30 families with 100 offspring, no deviation from the rule of at least four codominant alleles at one genetic locus was found. Linkage between C81 gene(s) and PGM1a encoded on chromosome 1 could be confirmed. The following estimates were obtained: (formula; see text) with S theta being the standard error of the maximum likelihood estimate theta. The new technique for allotyping human C81 at the subunit may provide a new tool for the differentiation of qualitative and quantitative variation of the eighth component of human complement.

Alleles↗
PubMed1986

Clinical features of inflammatory joint and spine manifestations in Crohn's disease.

167 patients with Crohn's disease were investigated for joint and spine inflammation. Arthritis was observed in 23 patients (14%), sacroiliitis in 24 (14%), and sacroiliitis in combination with arthritis in 11 patients (7%). 15 patients (9%) had ankylosing spondylitis; 9 of them were HLA-B27 positive (60%). A parallel pattern in the course of bowel disease and joint inflammation was observed in 22 out of 34 patients with arthritis (59%). An association between the localization of Crohn's disease and the type of spondylarthritis could not be demonstrated. Patients with arthritis alone developed erythema nodosum (35%) or aphthous stomatitis more often (21%) than patients without spondylarthritis+ (6% and 12%, respectively). Other extra-intestinal manifestations of Crohn's disease did not reveal any association with the development of spondyloarthritis.

Adolescent↗
PubMed1985

[Genetics of Crohn disease: study of the HLA association in 169 patients].

Histocompatibility (HLA) antigen phenotypes have been studied in 169 patients with Crohn's disease. The following results could bei shown: HLA-Aw33, -B45 and -Cw3 showed a positive association and HLA-A26, -DR3 and -DRw8 a negative association with Crohn's disease compared to healthy controls. However, when the p-values were corrected by multiplying them by the number of determined antigens per gen-locus, the differences were not significant. Patients with a late onset of the disease (greater than 25 years) showed a statistical significant negative association with HLA-DR3. Numerous studies revealed no significant association between Crohn's disease and HLA-antigens except Smolen et al. (HLA-B12). The significant association of Crohn's disease and HLA-B12 reported by Smolen et al. could be caused by an increased frequency of HLA-B45 as we found in our patients.

Adolescent↗
PubMed1985

Another family with a silent allele of properdin factor B polymorphism (BF QO).

In five of eight members of a three generation family the existence of a silent allele of the properdin factor B polymorphism (BF QO) was indicated by immunofixation of BF electrophoretic variants and by the hemolytic overlay after isoelectric focusing of BF allotypes. This was further supported by the results of HLA-A, B, C, DR, C2, C4A, C4B, GLO-typing. BF protein was decreased in all heterozygous BF deficient family members. The absolute hemolytic activity, however, was obviously compensated for by an increased relative functional activity of the normal S or F alleles on the other chromosome.

Alleles↗
PubMed1985

No interaction between HLA and immunoglobulin IgG heavy chain allotypes in early onset type 1 diabetes.

Immunoglobulin heavy and light chain genes are often discussed as susceptibility genes for insulin dependent (type 1) diabetes mellitus (IDDM) in addition to HLA-DR3 and DR4. Accordingly we analysed 175 unrelated patients for an interaction between immunoglobulin allotype antigens (Gm) and HLA. While DR3 and DR4 antigens and DR3/DR4 heterozygotes occur significantly more often among diabetics than among normal controls, their Gm allotype frequencies are very similar. An interaction between special Gm allotypes and phenotypes, on the one side, and DR3, DR4 or DR3, 4 on the other side could not be demonstrated.

Diabetes Mellitus, Type 1↗
PubMed1985

Genetic restriction of autoreactive acetylcholine receptor-specific T lymphocytes in myasthenia gravis.

Human autoreactive helper T lymphocytes with specificity for acetylcholine receptor (AChR) were isolated from three HLA-DR3-positive patients who had myasthenia gravis (MG), an autoimmune disease known to be associated with HLA-DR3 in the North European population. The antigen-specific T cells were evaluated for genetic restriction. Antigen presentation studies were performed with mitomycin C-treated accessory cells from a panel of HLA-typed unrelated donors. AChR-induced proliferation of the autoreactive T cells was maximal in the presence of autologous or HLA-DR-compatible antigen-presenting cells. In two DR-heterozygous patients both parental DR specificities served as restriction elements of the polyclonal AChR-reactive T cell populations. Preferential restriction to HLA-DR3 was observed in one patient, but this was also seen with PPD-specific T cells from the same donor. A series of monoclonal antibodies against HLA class II molecules was used for inhibition experiments. The inhibitory effects of the antibodies were not due to unspecific toxicity and could be observed after separate treatment of the antigen-presenting cells but not of the responding T cells. Several monoclonal antibodies against monomorphic HLA-DR determinants (DA 231, MAS 53, MAS 54, L243, OKIa1) had pronounced inhibitory effects. Anti-HLA-DQ(DC) monoclonal antibodies (Leu-10; TU 22) had only mild or no inhibitory effects in two patients but significantly inhibited AChR-specific T cells in one patient. A monoclonal antibody against HLA-DR3 (antibody 16.23) was not or was only weakly inhibitory in the DR3-positive patients, although it bound to autologous T line cells and B cells by indirect immunofluorescence. In one patient it was possible to compare the inhibition patterns of AChR-specific and PPD-specific T cells. Most of the monoclonal antibodies affected AChR- and PPD-specific T cells to a similar extent, but three antibodies (TU 22, 36, 39) inhibited PPD-specific T cells more than AChR-specific T cells, indicating the possibility of differential restriction of antigen- and autoantigen-specific T cells. It is suggested that the in vitro system described here may be helpful for the evaluation of anti-HLA class II antibodies as potential immunotherapeutic reagents.

Animals↗