HLA antigens in Italian multiple sclerosis patients

We analyzed HLA-A,-C,-B,-DR and-DQ specificities in 104 Italian multiple sclerosis patients and in 905 healthy controls. The frequencies of HLA-A23, A26, Cw4, DR3 and, especially DR5 antigens were significantly higher in multiple sclerosis patients than in controls. Patients with progressive course were characterized by high frequencies of B7, B8 and DR3 antigens: Cw1 and DRw11 show a negative correlation with the extent of intrathecal IgG production. These data confirm that the HLA system may influence the clinical expression and the immune responses to the disease.

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Sommario Abbiamo analizzato le specificità HLA del locus A, C, B, DR e DQ in 104 pazienti italiani affetti da Sclerosi Multipla e in 905 controlli sani. La frequenza degli antigeni A23, A26, Cw4, DR3 e soprattutto DR5 era aumentata in maniera significativa nei pazienti rispetto ai controlli. I pazienti con decorso progressivo erano caratterizzati da un'alta frequenza degli antigeni B7, B8 e DR3; Cw1 e DRw11 mostravano una correlazione negativa con l'estensione della produzione intratecale di IgG. Questi dati confermano che il sistema HLA può influenzare l'espressione clinica e le risposte immunitarie nella malattia.

     

HLA and prognosis in multiple sclerosis

The patients of a multiple sclerosis (MS) incidence cohort with 25 years of longitudinal follow-up were typed for HLA-DR and DQ. This type of cohort provides reliable data for gene frequencies and prognostic studies. The influence of sampling bias, mainly due to mortality during the long follow-up, was accounted for. A positive association between MS and DR15,DQ6 was confirmed, but this haplotype did not influence prognosis. There was no difference in haplotype frequency between relapsing-remitting and primary chronic progressive MS. DR17,DQ2 was significantly over-represented in the quartile with the most malignant course. The haplotype DR1,DQ5, which was found rather less frequently in MS patients, also tended to be associated with a poorer prognosis.     

HLA and familial multiple sclerosis

Some data suggest an environmental perhaps a viral factor but also of a genetic factor in the etiology of multiple sclerosis. Among the latter is the notably increased risk for a twin when the other twin has the disease, a risk further increased if they are monozygotic. There is also a greater than chance frequency of common HLA haplotypes in 2 affected siblings. The frequency of familial forms of multiple sclerosis is estimated at approximately 6 p. 100. We have studied 14 families of which 12 included 2 members with multiple sclerosis and 2 with 3 affected members. Parental relation between patients was parent to child (7 cases), brother to sister (5 cases), sister to sister including two pairs of twins (4 cases) and cousin to cousin on the mother's side (2 cases). When compared with non-familial multiple sclerosis there were no particular features in clinical disorders or course: 4 forms were progressive, the others evolving by episodes. In 26 patients in whom HLA antigens were determined, the DR2 antigen was present 19 times, the B7 antigen 9 times and the A3 antigen 7 times. In the 8 pairs of siblings with multiple sclerosis, 2 were HLA-identical and 5 semi-identical. One pair had no common haplotype. Grouping of HLA in 22 healthy members allowed 8 genealogic trees to be established. If a gene for susceptibility to multiple sclerosis exists, it is of low penetration, of dominant transmission and of limited frequency. It probably lies close to the region D of chromosome 6, because of the disequilibrium of crossed linking with A3, B7 and DR2 antigens.     

HLA class II alleles and multiple sclerosis in Tunisian patients

Objective

The aim of our study was to investigate the association of HLA-DRB1 and -DQB1 alleles with multiple sclerosis (MS) in a Tunisian population and their effect on age at onset and disease severity.

Methods

58 MS patients and 105 healthy controls were genotyped for HLA class II alleles by PCR-SSP technique.

Results

An association of MS with HLA-DRB1*15 was found (14.7% vs 3.8%, OR (95% CI) = 4.34 (1.69–11.39), p_c = 2.5 × 10⁻³) after Bonferroni's correction. Moreover, the DRB1*15–DQB1*06 (13.8% vs 2.8%, OR (95% CI) = 5.44 (1.92–17.41), p_c = 1.1 × 10⁻³) and DRB1*04–DQB1*04 (8.6% vs 1.9%, OR (95% CI) = 4.86 (1.36–21.62), p_c = 0.028) haplotypes were found to confer a susceptibility to multiple sclerosis.

Conclusion

To our knowledge, this is the first study performed to analyze the association of HLA-DRB1/DQB1 alleles on MS susceptibility in Tunisia. The modern Tunisian gene pool shows some degree of heterogeneity and reflects a significant gene flow from Mediterranean regions.     

HLA types and immunity in multiple sclerosis

HLA types and levels of humoral and cell-mediated immune responses to several antigens were studied in a large group of patients with multiple sclerosis, and in controls. Patients were more likely than controls to have the DRw2 antigen. They had higher mean antibody titers to measles but not to cytomegalovirus, herpes 1, or herpes 2, and had less competent cell-mediated responses. Antibody titers to measles were lower and cell-mediated immune responses were more effective in patients with the DRw2 antigen in patients than in patients without it. This apparent specificity for measles suggests that the etiology of multiple sclerosis is related to the immune response to measles or related viruses.     

HLA antigens in multiple sclerosis.

The frequency of the MLC activating HLA-Dw2 determinant was found significantly increased to 68% among 37 patients with long-standing multiple sclerosis, compared to 30.2% among healthy controls. A similar (or stronger) degree of association was found with an "Ia-like" B cell specificity, SOW, while the association with HLA-B7 was less apparent. No correlation between HLA-Dw2 and signs of local synthesis of oligoclonal IgG or measles or rubella virus antibodies in the CNS was observed.     

HLA class II and response to interferon-beta in multiple sclerosis

OBJECTIVE: To study the relationship between human leucocyte antigen (HLA) genotype and clinical response to interferon-beta (IFN-beta). METHODS: We analysed the HLA class II genotypes of 96 multiple sclerosis (MS) patients treated with IFN-beta. The patients were classified as responders or non-responders according to clinical criteria: one or more relapses or a sustained increase after 1 year treatment compared with the year prior to IFN-beta therapy of > or = 0.5 points on the Expanded Disability Status Scale (EDSS). RESULTS: There were 66 (69%) responders and 30 (31%) non-responders. Baseline clinical characteristics were similar. We found no association between HLA class II alleles and clinical response to IFN-beta. CONCLUSIONS: HLA genotype does not appear to influence the clinical response to IFN-beta in MS patients.     

Vaccination against infection in patients with multiple sclerosis

Bacterial and viral infections have been shown to induce relapses and accelerate the progression of multiple sclerosis (MS). Vaccination to prevent communicable disease in such patients is, therefore, of key importance. Reports of potentially detrimental effects of immunization on the course of MS, however, have prompted patients and physicians to adopt a cautious attitude towards the use of vaccines. The risks associated with a number of vaccines have been investigated in patients with MS. Vaccines against some diseases, such as tetanus and hepatitis B, are not associated with an elevated risk of MS exacerbation, whereas vaccines against other diseases, such as yellow fever, are contraindicated in patients with MS. Many patients with MS receive immunosuppressive or immunomodulatory therapy, which could make them more susceptible to infectious diseases and might also affect their ability to respond to immunization. Here, we review the indications for and possible adverse effects of vaccines in patients with MS, and address issues of vaccination in the context of immunomodulatory therapy for MS.     

The HLA locus and multiple sclerosis in Sicily

The authors report the analysis of HLA-class II allelic heterogeneity in a well characterized multiple sclerosis (MS) Sicilian dataset. Family-based association analysis revealed evidence for excess transmission to affected individuals for alleles HLA-DRB1*1501, DRB1*04, and DQB1*0302. When analyzed as haplotypes, the authors observed excess transmission for the DRB1*0400-DQB1*0302 haplotype. Sicilian patients share the HLA-DRB1*1501 susceptibility allele with affected living in continental Italy, but also display the allelic heterogeneity that characterizes Mediterranean populations.     

HLA determinants in familial multiple sclerosis.

HLA-A, -B, -C, -DR, -DQ antigens were studied in 11 multiplex MS families, 11 single-case MS families and 100 healthy subjects. The HLA DR4 was the most frequent antigen in all MS patients (p = 0.015). When the antigenic frequency in index familial cases was compared with that in single cases, the DR4 antigen was found to be more frequent (p = 0.01) in familial cases only. Furthermore, when the DR4 antigen was excluded from the analysis, we observed an increase in DR2 (p = 0.11) only in the familial MS cases. These results can be compatible with a multifactorial hypothesis according to which the HLA genes have an important role in MS susceptibility in familial cases.     

HLA complement gene polymorphisms in multiple sclerosis

We studied C4A, C4B, and Bf complement gene polymorphisms in 80 Italian patients with multiple sclerosis (MS). We observed a significantly higher frequency of C4AQ0 allele in patients with the relapsing-remitting form of MS than in ethnically homogeneous controls. Restriction fragment length polymorphism analysis by Southern blotting of the C4/CYP21 gene complex showed that a structural gene deletion was present in 45% of patients with the C4AQ0 allele. Our data support the hypothesis that relapsing-remitting MS and primarily chronic progressive MS are immunogenetically distinct diseases; further, complement factor abnormalities typical of autoimmune diseases could influence the pathogenesis of MS.     

Antibodies to nuclear and smooth muscle antigens in multiple sclerosis and control patients

Serum and CSF specimens of 30 MS patients and 30 age- and sex-matched control patients with other neurological diseases were tested for autoantibodies. Indirect immunofluorescense was used to detect smooth muscle antibodies and antinuclear antibodies in the serum. Antibodies against DNA and RNA in the serum and CSF were tested by solid phase radioimmunoassays. No significant differences in autoantibody levels were found between MS and control patients.     

HLA and multiple sclerosis in south east Wales.

A stronger association has been found between multiple sclerosis and HLA-DR2 than -DQwl in south east Wales (prevalence c 113/10(5)) in contrast to recent observations in north east Scotland (prevalence 178/10(5). The complex relationship between the HLA system and multiple sclerosis, demonstrated in this and other studies, is explained more easily under a polygenic model of inheritance, in which environmental events and genes interact, than by the presence of a single susceptibility gene.     

Autoreactivity to myelin antigens related to HLA associations with multiple sclerosis

Multiple sclerosis (MS) is considered as an immune process influenced by genetic and environmental factors. HLA-DR2 and -DR4 have been documented to be associated with MS. The HLA-dependent differences of immune response to myelin and other antigens might point out some relevant mechanisms in MS development The responses to myelin antigens and to PPD have been compared in 21 MS patients and 25 healthy controls (HCs) by primary proliferation and by short-term T-cell lines. There was a significantly higher response to MBP in DR2+ HCs compared to MS patients (SI: 5.9 versus 1.5, p = 0.02). In short-term T-cell lines, we observed a higher response to PLP30-49 in both DR4+ HCs and MS patients This response was significantly more frequent in DR4+ MS patients (34.6%) than both DR2+ MS patients (0%, p = 0.0001) and DR4+ HCs (7.7%, p = 0.001). The comparison between DR2+ and DR4+ MS patients has revealed that the response to MBP was also increased in DR4+ (p = 0.02). Among DR4+ groups, an increased PPD response was detected in HCs compared to MS (65.2% versus 33.3%, p = 0.01). These results may indicate that HLA-related differences to specific and recall antigens are detectable in MS and these differences may have implications in the disease pathogenesis.     

Class II HLA antigens in multiple sclerosis.

HLA typing in Wellington revealed a stronger association of multiple sclerosis with DR2 than with DQw1. The association with DQw1 appeared to be due to linkage disequilibrium of this antigen with DR2. These results, when considered in conjunction with other studies, are most easily explained by the hypothesis that susceptibility to multiple sclerosis is influenced by multiple risk factors, with DR2 being an important risk factor in Caucasoid populations.     

HLA antigens in multiple sclerosis amongst Indians.

The infrequency of multiple sclerosis in India may have genetic implications. We found (a) the HLA-A3 and HLA-B7 haplotypes amongst Indians to be lower than those reported in Caucasians, (b) no excess of HLA-A3 and HLA-B7 amongst our 27 multiple sclerosis patients compared to 330 controls; instead it was the reverse, (c) HLA-B12 as high as 74% in the "clinically definite" cases, against only 9% in controls, (d) a significant relative risk of MS amongst Indians with HLA-B12 haplotype. Attention is drawn to th higher incidence of MS amongst the small Parsee community and the high association of HLA-B12 in these patients.