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J Hors

Publications and source records attributed to J Hors.

At least 127 records · Page 7Linked to original sources
PubMed1984

[Preliminary study of HLA markers in French Catalonia].

Forty-two sets of parents and their two children, who had their origins for at least three generations in French Catalonia, were studied for HLA-A,B,C,DR and Bf alleles of the Properdine complement factors. Four haplotypes were observed to be in strong linkage disequilibrium (p less than 10(-3)): A1, Cw7, B8, DR3; Aw30 (Cw5), B18, BfF1, DR3; A1 (Cw6), B17; A29 or Aw23, Cw4, B12, BfF, DR7. The observed linkage disequilibria of these haplotypes in the French Catalonian population were compared with those already described among populations from the Basque country, the Toulouse area and Spanish Catalonia.

Adult↗
PubMed1984

Class II HLA-DC beta-chain DNA restriction fragments differentiate among HLA-DR2 individuals in insulin-dependent diabetes and multiple sclerosis.

HLA-DR2 allele is negatively associated with insulin-dependent diabetes and positively associated with multiple sclerosis (MS). A 2.2-kilobase-pair EcoRI DNA restriction fragment detected with a beta-chain HLA-DC cDNA probe was found to be strongly correlated with HLA-DR2 in the normal population, but was absent in HLA-DR2 insulin-dependent diabetic patients. This fragment was found in HLA-DR2 multiple sclerosis patients with the same frequency as in controls. A beta-chain HLA-DC 12-kilobase-pair BamHI fragment might differentiate multiple sclerosis patients from healthy individuals.

DNA Restriction Enzymes↗
PubMed1984

A linkage study between HLA and cutaneous malignant melanoma or precursor lesions or both.

In seven pedigrees displaying the familial atypical multiple mole-melanoma (FAMMM) syndrome, three successive linkage analyses were performed between HLA and an assumed dominant gene determining respectively each of the following affected phenotypes: (1) precursor lesions, (2) cutaneous malignant melanoma (CMM), and (3) precursor lesions or CMM or both. Close linkage could be excluded in (1) and (3). However, if the transmission of malignant melanoma itself were assumed to be due to a single gene different from the one responsible for precursor lesions, a maximum lod score of 1.64 was observed at a recombination fraction of 5%, assuming low penetrance values. These different results are discussed in respect to the possible mechanisms causing the familial distribution of these traits. Two alternative hypotheses were proposed. Either the FAMMM syndrome is a rare genetic entity not closely linked to HLA or the association and transmission of precursor lesions and CMM in families are due to several factors among which HLA might play a role.

Disease Susceptibility↗
PubMed1984

Evaluation of recurrence risk in siblings of diabetic children: importance of age and birth order in relation to HLA genotypes.

In order to identify factors other than the HLA-linked susceptibility involved in the risk to the siblings of diabetic children, we compared the age at onset, birth order and HLA genotypes in 23 IDD multiplex (Mx) families and 140 simplex (Sx) families. The results showed a relationship between age and recurrence risk in sibs. Probands (= 1st affected sibs) of Mx families were significantly younger at onset (5.8 +/- 0.8 yr) than probands of Sx families (9.0 +/- 0.4 yr, p less than 0.01). The 2nd affected sibs of Mx families, although affected at an older age (12.4 +/- 1.6 yr), had been significantly younger at the time of the proband's onset, than the siblings who have remained unaffected (6.2 +/- 1.2 vs 11.5 +/- 0.5 yr, p less than 0.01). Probands of Mx families were more often the first born and probands of Sx families, more often came later in the birth order (p less than 0.02). Prevalence of IDD was higher among siblings born after than among those born before the proband (12% vs 4%, p less than 0.002). The HLA haplotype distribution in unaffected siblings deviated from the random assortment in relation to birth order, showing an excess of HLA-identical sibs born before the proband and, inversely, an excess of non-identical sibs born after the proband. The results suggest that age-dependent factors are likely to increase the penetrance of HLA-linked IDD susceptibility. These factors could be related to the environmental insult. However, a genetically determined form of type I diabetes characterized by higher familial penetrance and earlier onset cannot be ruled out.

Age Factors↗
PubMed1984

HLA and cancer.

Explore the source record for details and available documents.

HLA Antigens↗
PubMed1983

[Genetic and environmental factors in insulin-dependent diabetes].

Insulin-dependent diabetes results from the interaction of genetic, immunological and environmental factors. In view of the association between insulin-dependent diabetes and HLA system, it has been postulated that the diabetogenic gene(s) is (or are) located in the region of the DR locus in that system. The hypothesis of viral factors is supported by epidemiological arguments and experimental models but has only been exceptionally confirmed in man. The fact that anti-islet antibodies are frequently detected at the onset of insulin-dependent diabetes or even before the first symptoms develop suggests that an auto-immune mechanism might be involved in the destruction of beta-cells. Although the mode of inheritance of genes supposed to predispose to insulin-dependent diabetes as well as the mechanisms behind the pancreatic lesion are still poorly understood, determining "markers" of the disease should eventually make it possible to detect subjects at risk of diabetes and to prevent its development.

Antibody Formation↗
PubMed1983

[Role of transfusions and significance of HLA-A, B and DR compatibility in renal transplants].

The results study of renal allograft performed in the France-Transplant network, shows the beneficial effect of blood transfusions on graft survival; their immuno-suppressive effect allowed the tolerance of the transplant, despite of the presence, at times, of incompatibilities HLA. In this work, we have studied the effect of HLA-A, B, DR incompatibilities in 803 unrelated recipients according to their preimmunized status. In the 303 presensitized patients (by transfusion or transplantation) we show clearly the strong effect of the HLA compatibility and the additive effect of the three loci A, B, DR (94% of graft survival at two years for the best matched v.s. 36% for the worst). In the 500 non responder patients, there is no effect of the compatibility A, B, DR (69% for the best matched v.s. 71% for the worst). Presensitized patients reach currently 50% of the waiting list of dialysed. Cooperative efforts should avoid heavily mismatched transplants in case of preimmunization.

Actuarial Analysis↗
PubMed1983

HLA and susceptibility to Hodgkin's disease.

Strong arguments supporting a genetic linkage between susceptibility to HD and HLA are reported. These observations are based on data from 33 multiplex case families, gathered from international series and from our own studies. They confirm the disturbed segregation of HLA haplotypes among pairs of affected siblings (P less than 0.0005). An excess of a shared haplotype among first cousin pairs of patients is also observed (P less than 0.05). When both sib pairs and cousins are taken together, the segregation distortion is even greater (P less than 0.0002). Although the excess of HLA-identical affected sib pairs would favor a recessive mode of transmission of the disease, the lod score analyses do not allow one to conclude a simple genetic pattern. A two-gene model, based on epistatic cooperation, is discussed and could fit with an intermediate mode of transmission. The review of population data confirms the generally admitted trend of higher susceptibility borne by HLA-A1. There are converging arguments in favor of the prevalence of A1, B5, B18 in HD, and in particular A1 in the mixed cellularity form, while the haplotype, A1, B8, predominant in long survivors seems to possess a protective effect. It is expected that more data from multiplex families and prospective series of unrelated patients, fully HLA typed, may help to bring about a better understanding of the first reported HLA linkage with malignancy.

Disease Susceptibility↗
PubMed1983

HLA-DR2 in two sibships with insulin-dependent diabetes mellitus.

We report two families selected from 124 genotyped Caucasian insulin-dependent diabetes mellitus (IDDM) families because of unusual features. In both families, all offspring are affected and four out of six bear the allele HLA-DR2 which is an uncommon phenotype among diabetic patients. Onset before the age of 1 year in all the patients of one family, association with optic atrophy in the other, and the existence of pairs of affected sibs of different HLA types in both, are infrequent findings and support the evidence of heterogeneity in IDDM.

Age Factors↗
PubMed1983

[Computer analysis of anti-HLA sera: ANASER. Its application in kidney transplantation].

ANASER is a system of 3 computer programs for the analysis of sera from multi-transfused patients, multiparous women and dialysed patients awaiting kidney transplantation, which react against one or more HLA antigens. This system permits: 1) the recognition of one or more HLA specificities in each serum using iterative analyses. 2) The calculations of correlation coefficients among several sera. 3) The drawing of positive serological reactions according to either a given sera or to a given antigen. It can be used for two main purposes: 1) to permit selection of the best sera for HLA typing (positive correlations). 2) To study the preimmunization of dialysed patients awaiting kidney graft. Owing to sequential comparison of the consecutive bleedings from the same individual, they allow the definition of a pattern of anti-HLA immunisation, and in the case of large spectrum antibodies, the specification of antigens not concerned by the antibodies produced (negative correlations). ANASER may help in the choice of the best compatible transplant for hyperimmunized patients, who need a precisely matched organ.

Antibodies↗
PubMed1983

Age--related heterogeneity of insulin-dependent diabetes mellitus.

One hundred and thirty-three insulin-dependent diabetic (IDD) patients were genotyped for HLA-A, B, C, DR and 123 of them for Bf. The study shows a relationship between these genes and the age of onset of diabetes and emphasizes the possible heterogeneity of the disease. When patients under the age of 0 years at the onset of the disease were compared with those aged 11 to 29 years, a significant excess of HLA-B18 (41% versus 15%, p less than 0.001) and BfF1 (40% versus 21%, P less than 0.05) was observed. The haplotype B18, BfF1 was also more frequent in the first group of patients (haplotype frequency 18% versus 6%, p less than 0.02). The frequency of the whole haplotype Cw5, B18, BfF1, DR3 and of its segment BfF1, DR3, and the strength of the gametic associations between these alleles were much higher in IDD patients than in non-diabetic controls, irrespective of the age of onset of their diabetes. The association between early age of onset of IDD and the B18, BfF1 haplotype independently of DR3 (no association between age and DR3) suggests that a factor influencing the onset of the disease in young children could be under the control of (1) gene (s) in linkage disequilibrium with B18 and/or BfF1.

Adolescent↗
PubMed1982

Selective reactivity of sera from alloimmunized sheep and cattle against human T and leukemia cells.

Human B and T lymphocytes from a panel of healthy individuals were tested against serial dilutions of 68 mare, 81 cow, 7 sow, and 87 ewe sera. All the animals had been alloimmunized by pregnancies and/or blood transfusions. Weak correlations with HLA-A, B, C, and DR specificities were found in 20 sera. Twelve other sera, 9 from ewes and 3 from cows, had a strong reactivity against T lymphocytes but weak or no reactivity against B cells, spleen null cells, granulocytes, and platelets, suggesting a non-major histocompatibility complex (MHC) cross-reactivity. They were cytotoxic for most of the cells of malignant proliferative origin tested thus far, including T acute lymphoblastic leukemia (T ALL), common ALL (cALL), acute myeloblastic leukemia (AML), and Sezary cells, but were negative with B lymphoblastoid cell lines and cells from patients with B chronic lymphocytic leukemia (CLL) and chronic myelocytic leukemia (CML). The hypothesis that humans and certain other mammals share a common determinant on T-lineage cells and some malignant cells is advanced.

Animals↗
PubMed1982

HLA haplotype study of 53 juvenile insulin-dependent diabetic (I.D.D.) families.

R4 heterozygotes was observed. By contrast, the observed frequency of patients homozygous for DR3 or DR4 was not increased, but even slightly decreased. The data support a model of inheritance comprising at least two closely linked specifically "diabetic" loci (most of the time marked by B18, BfF1, DR3 and B15, BfS, DR4) and a non-specifically "diabetic" haplotype favouring auto-immunisation (most of the time marked by B8, BfS, DR3). This model is discussed in the light of the presented data and of those of the literature.

Adolescent↗