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J Hillert

Publications and source records attributed to J Hillert.

At least 73 records · Page 4Linked to original sources

No linkage or association of a VNTR marker in the junction region of the immunoglobulin heavy chain genes in multiple sclerosis.

Multiple sclerosis (MS) is a demyelinating inflammatory disease of the central nervous system. Autoantibodies are though to participate in the pathogenesis. Previous reports on the role of immunoglobulin (Ig) variable gene segments in MS are contradictory. Here, by using a highly polymorphic variable number tandem repeat (VNTR) marker located in the centre of the IgH chain locus, we demonstrate a lack of linkage and association with MS in 34 multiplex families and 113 sporadic MS patients in Sweden. Stratification for the presence or absence of the MS-associated HLA-Dw2 haplotype did not influence the negative outcome. We conclude that the IgH chain genes are unlikely to play a role in genetic susceptibility to MS in the Swedish population.

Chromosomes, Human, Pair 14↗

Linkage analysis of HLA class II genes in Swedish multiplex families with multiple sclerosis.

We assessed the influence of human leukocyte antigen (HLA) class II as susceptibility genes in multiple sclerosis (MS) by linkage analysis. Other research groups, who have shown negative results in studies on affected sibling pairs, have questioned the influence of the HLA class II genes, although they confirmed the association of the DR15,DQ6,Dw2 haplotype to MS. In this report, we find a significant lod score (>3) when using a 2-point linkage analysis of 49 small Swedish nuclear MS families with at least two affected family members, typed for HLA class II alleles by PCR amplification with sequence-specific primers. We obtained maximum lod scores when we used dominant or intermediate models with low penetrance. We found that the positive effect on the total lod score was not confined to those families carrying the presumed susceptibility HLA-haplotype Dw2. This observation supports the notion of a functional role of the HLA class II molecules themselves in MS. In addition, we observed significant transmission distortion and an intrafamilial association of the MS-associated class II haplotype HLA-Dw2. These results indicate that the HLA class II genes are of clear importance for MS in the studied population.

Disease Susceptibility↗

Distribution of HLA-Dw2 in optic neuritis and multiple sclerosis indicates heterogeneity.

UNLABELLED: The human leukocyte antigen (HLA) phenotype Dw2 is known to be increased in multiple sclerosis (MS), but only slightly in optic neuritis (ON). MATERIAL AND METHODS: 127 consecutive patients with unilateral monosymptomatic ON were typed genomically for HLA-DR and -DQ genes. RESULTS: The frequency of HLA-Dw2 among ON patients (47%) was found to be significantly higher than among 250 controls (30%) but significantly lower than in a group of 245 MS patients (60%), all of the same ethnic origin. At the group level, these figures can be calculated to indicate that 53% of the ON patients belong to the group of "MS-type ON" (95% confidence limits 25-78%). A compilation of published data on the frequency of the HLA-DR17(3), DQ2 haplotype, prompted by a slight increase in this material, revealed a significant association with this haplotype in ON, after compensation for the increase of Dw2. CONCLUSION: ON differs from both MS and controls regarding HLA-Dw2. Thus, a substantial number of patients with ON may suffer from conditions not immuno-genetically related to MS, which might be designated as non-MS type ON. This condition may be more common in men and in young patients of both sexes.

Adult↗

Tumor necrosis factor alpha-308 alleles in multiple sclerosis and optic neuritis.

Tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, is believed to play an important role in multiple sclerosis (MS) pathogenesis. A bi-allelic polymorphism in the TNF-alpha promoter region (TNF alpha-308), has been reported to influence levels of TNF-alpha production. In the present study, we investigated the TNF alpha-308 polymorphism in 93 patients with MS, 17 patients with optic neuritis (ON) and 95 healthy individuals using an allele-specific PCR technique. Allelic genotype was compared with TNF-alpha mRNA expression levels and HLA class II phenotypes. No significant difference regarding the TNF alpha-308 polymorphism was observed between MS patients and controls. Specifically, the less common allele, TNF2, which is associated with higher expression levels of TNF-alpha, was somewhat less frequent among MS patients. In fact, analysis of 19 patients homozygous for the MS associated HLA-DR-DQ haplotype HLA-Dw2 showed that this haplotype does not carry the TNF2 allele. In addition, in 47 patients, the TNF-alpha alleles did not correlate with expression levels measured as numbers of TNF-alpha expressing cells. Thus, we found no evidence for an important role of TNF alpha-308 polymorphism for genetic susceptibility to MS.

Alleles↗

Expression of IFN-gamma, IL-4, and TGF-beta in multiple sclerosis in relation to HLA-Dw2 phenotype and stage of disease.

Multiple sclerosis (MS) is associated with upregulation of both proinflammatory (interferon-gamma, IFN-gamma) and immunosuppressive (transforming growth factor-beta, TGF-beta) cytokines. To examine a possible relation between the MS-related HLA haplotype Dw2 and cytokine profiles, we used in situ hybridization with labeled cDNA oligonucleotide probes to detect transcripts of the T helper type 1 (Th 1) cell related IFN-gamma, the Th2 cell related interleukin-4 (IL-4) and of TGF-beta in blood and cerebrospinal fluid (CSF) mononuclear cells from 62 patients with MS. Compared to patients with other neurological diseases and healthy controls, MS patients had elevated numbers of IFN-gamma, IL-4 and TGF-beta mRNA expressing cells in blood and further augmented in CSF. Although several HLA-Dw2-positive individuals showed very high numbers of cells expressing these cytokines, no significant difference was found in comparison with Dw2-negative patients. However, expression of IL-4 and TGF beta mRNA was significantly increased in patients with shorter duration and minor disability and, for IL-4, in patients still in the relapsing-remitting phase compared to patients with secondary chronic progressive MS. Surprisingly, these changes which favour a beneficial, disease-downregulating effect of IL-4 and TGF-beta in MS, were found to be confined to HLA-Dw2-positive patients. Our findings suggest that the HLA phenotype does not influence the overall level of immune reactivity in MS, but may distinguish subgroups characterized by particular cytokine expression patterns.

Adolescent↗

Human leukocyte antigen studies in multiple sclerosis.

Multiple sclerosis (MS) has been associated with HLA-DR2 for more than 20 years, and a large number of studies have addressed the relation between MS and the HLA class II genes, which are our major immune-response genes. This has produced a complex and confusing picture that is difficult to interpret. With the advent of reliable and comprehensive DNA-based typing techniques, it is now possible to extract a coherent pattern from this mass of data. The associated haplotype has been specified to HLA-Dw2 in cellular typing nomenclature, which equals DR15,DQ6 by serology, and DRB1*1501,DQA1*0102,DQB1*0602 in sequence-based terminology. This haplotype is increased among groups of MS patients worldwide, although most strongly in North and West Europeans, and it is the only haplotype with a clear importance in MS. Attempts to map this association within the haplotype have not been successful.

Alleles↗

Optic neuritis: findings on MRI, CSF examination and HLA class II typing in 60 patients and results of a short-term follow-up.

Optic neuritis (ON) is a common first manifestation of multiple sclerosis (MS), and examination of patients with ON provides opportunities to study the early clinical stages of MS. This prospective study compares results of brain magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) examinations and HLA-Dw2 phenotyping in 60 consecutive patients with ON. At a median of 17 days after the onset of ON, 69% had oligoclonal IgG bands, and at a median on 79 days after onset, 53% had multiple (> or = 3) white matter lesions on MRI. Subgroup analyses revealed that MRI abnormalities and oligoclonal IgG bands were equally common in patients examined early or late after the onset of ON. Strong correlations were found between the presence of MRI abnormalities and oligoclonal IgG bands. The HLA-Dw2 phenotype was significantly increased in ON patients compared with controls, but also significantly different from a group of MS patients from the same geographical area. A significant relation was found between Dw2 phenotype and oligoclonal IgG bands. During a mean follow-up time of about 2 years, the diagnosis in 17 of the patients changed to clinically definite MS. Initially, 16 of them had oligoclonal IgG bands and 12 had three or more MRI lesions. Both MRI and CSF studies are important diagnostic tools in the workup of ON patients.

Adolescent↗

The HLA-Dw2 haplotype segregates closely with multiple sclerosis in multiplex families.

Multiple sclerosis (MS) is associated with the HLA class II specificity Dw2, but the importance of its influence has been questioned, since sib-pair analysis has failed to show linkage with this haplotype. However, the use of 'identity by descent' (IBD) analysis may not be ideal, since it does not make use of the facts that (i) the Dw2-haplotype is the only haplotype with a confirmed role in MS, and (ii) it performs its influence in a dominant manner. We have investigated nine Swedish multiplex MS families. In eight of the families, the Dw2 haplotype occurred in MS patients. Within these families, Dw2 was shared by all 17 individuals with MS. In a compilation of 48 published multiplex MS families in which at least one patient carried Dw2, only three of 107 individuals with MS did not carry the Dw2 haplotype. This indicates that the Dw2 haplotype, when present in familial MS, may confer a stronger influence in MS susceptibility than generally recognized.

Genes, MHC Class II↗

Multiple sclerosis: occurrence of myelin basic protein peptide-reactive T cells in healthy family members.

Genetic factors influence the susceptibility to multiple sclerosis (MS). This disease is accompanied by augmented T cell responses to CNS myelin components such as myelin basic protein. To evaluate the familial occurrence of such T cell autoreactivity, we have studied 12 MS families including 37 healthy first-degree relatives for occurrence of numbers of interferon-gamma (IFN-gamma) secreting cells among blood mononuclear after culture in presence of myelin basic protein (MBP), eight synthetic MBP peptides and the control antigen acetylcholine receptor (AChR). There were no differences between MS patients and healthy family members regarding frequencies of autoreactive T cells recognizing MBP, the eight different MBP peptides or AChR. None of the MBP peptides predominated as T cell antigen among the MS patients or their unaffected family members. In some families the highest number of MBP peptide reactive T cells were found among unaffected family members. No correlation was observed between numbers of MBP or MBP peptide reactive T cells in various subjects and their HLA-DR-DQ phenotypes. In conclusion, this study has revealed the presence of MBP and MBP peptide reactive T cells of similar frequencies in MS patients and their healthy family members.

Adult↗

Immunoglobulin gamma constant gene region polymorphisms in multiple sclerosis.

It is well-established that multiple sclerosis (MS) in Caucasians is associated with HLA-DR2. A number of studies have indicated that other genes may also influence the susceptibility to MS. Gm allotypes of immunoglobulin (Ig) genes have been reported to be associated with MS several times, but the described associations differ and have not been confirmed. We report here the results of restriction fragment length polymorphisms (RFLP) analysis of the constant gene regions of immunoglobulin gamma (IgG C) 1, 2 and 3 in MS patients and controls, using the restriction enzymes TaqI, PvuII and BstEII. No significant differences were observed, regardless of subgrouping of patients according to clinical disease type or HLA class II phenotype. These results are in contrast with a previous study where a BstEII RFLP was found to differ between MS patients and controls. In conclusion, the hypothesis that constant gene segments of the IgG genes confer susceptibility to MS still lacks convincing experimental support.

Genes, Immunoglobulin↗

Susceptibility to demyelinating polyneuropathy in plasma cell dyscrasia may be influenced by amino acid position 9 of the HLA-DR beta chain.

Fifty-five patients with plasma cell dyscrasias were investigated by genomic typing for HLA-DR and -DQ genes by restriction fragment length polymorphism, neurophysiology and for presence of anti-myelin-associated glycoprotein (MAG) antibodies. In 26 patients, a polyneuropathy (PN) of demyelinating type was established. Among these individuals, an association was found with the presence of a tryptophan amino acid residue at position 9 of the DR beta chain (P < 0.01). This position is part of the first hypervariable region of the DR beta chain, and may be of importance in determining preferential peptide-binding capacity of the HLA-DR molecule. The presence of anti-MAG antibodies in 15 out of 17 patients with an IgM M-component and demyelinating PN (14 of these 15 individuals carrying a tryptophan at position 9) supports the pathogenic role of an autoimmune response against MAG. The finding of an HLA class II association may indicate a pathogenic role of T cell immunity in this condition.

Adult↗

HLA and MS.

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HLA-D Antigens↗

Multiple sclerosis is associated with genes within or close to the HLA-DR-DQ subregion on a normal DR15,DQ6,Dw2 haplotype.

The HLA class II haplotype DR15,DQ6,Dw2 is associated with an increased risk for multiple sclerosis (MS). It has previously been shown that this haplotype extends to the HLA-DQA2 locus but not to the HLA-DP subregion. We report the distribution in 148 MS patients and 158 healthy controls of Taq I restriction fragments of the C4, cytochrome P-21 (CYP21), and HLA-B genes. Approximately 90% of the DR15,DQ6,Dw2 haplotypes extend to the C4/CYP21 loci and 50% to the HLA-B locus, indicated by a significant association of the haplotype with restriction fragments of these loci. However, there was no independent association in MS patients with these genes. This indicates that the susceptibility to MS is coded for by genes within or close to the HLA-DR-DQ subregion. Furthermore, the delineation of the DR15,DQ6,Dw2 haplotype is very similar in MS patients and control subjects. This observation supports the hypothesis that "normal" genes, common to all carriers of the DR15,DQ6,Dw2 haplotype, confer the increased genetic susceptibility to MS associated with this haplotype.

Blotting, Southern↗

Increased numbers of T cells recognizing multiple myelin basic protein epitopes in multiple sclerosis.

Myelin basic protein (MBP)-autoreactive T cells have a crucial pathogenetic role in experimental allergic encephalomyelitis (EAE) and certain MBP epitopes may be immunodominantly recognized. The heterogeneity and quantity of the T cell response to different epitopes of MBP in multiple sclerosis (MS) and non-MS controls is not so clearly defined. We now study T cell reactivity to six different peptides of MBP in MS compared to controls in short-term cultures of blood mononuclear cells by measuring numbers of T cells that secrete interferon-gamma in response to antigen. In comparison with controls, MS patients showed dramatically increased numbers of MBP peptide-reactive T cells with mean values varying between 10.4 and 22.5 per 10(5) blood mononuclear cells. Among those MBP peptides examined (amino acid 1-20, 63-88, 89-101, 96-118, 110-128 and 148-165), no single peptide is preferentially recognized. Neither is any preferential response apparent after subdivision of the MS patients according to their HLA-DR genotype. Our findings suggest that a quantitative increase of a broad repertoire of myelin-autoreactive T cells with capacity to secrete IFN-gamma can be important for the pathogenesis of MS.

Adult↗