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Biomedical subjects

P S Sorensen

Publications and source records attributed to P S Sorensen.

15 recordsLinked to original sources

CD4(+) memory T cells with high CD26 surface expression are enriched for Th1 markers and correlate with clinical severity of multiple sclerosis.

An aberrant immune activation is believed to be important in the pathogenesis of multiple sclerosis (MS). Expression of CD4(+) T lymphocyte surface molecules indicative of immune activation and effector functions has been correlated with disease severity and activity. CD4(+) CD45R0(+) CD26(high) memory T lymphocytes contained the high levels of markers of Th1, activation, and effector functions and cell counts of this subset correlated with MS disease severity. This subset had lower expression of PD-1, CCR4, and L-selectin in MS than in controls. These changes were only partially normalised by treatment with interferon-beta. We point to this subset as a putative target for immunological monitoring of MS disease activity and of treatment efficacy.

Adult↗

Dynamic T-lymphocyte chemokine receptor expression induced by interferon-beta therapy in multiple sclerosis.

Treatment with interferon (IFN)-beta reduces clinical disease activity in multiple sclerosis (MS). Using flow cytometry, an enzyme-linked immunosorbent assay and a real-time polymerase chain reaction, we studied in vivo IFN-beta-induced effects on CD4(+) T-lymphocyte chemokine receptor expression as these influence central nervous system (CNS) transmigration and inflammation. At 'steady state' (>/=1 day after the most recent IFN-beta injection), IFN-beta treatment increased CD4(+) T-cell surface expression of CC chemokine receptor (CCR)4, CCR5 and CCR7 after 3 months of treatment, whereas that of CXC chemokine receptor (CXCR)3 was unaltered. Conversely, at 9-12 h after the most recent IFN-beta injection, CCR4, CCR5 and CCR7 expressions were unaltered, while CXCR3 expression was reduced. CD4(+) T-cell surface expression of CCR4 was significantly lower in untreated MS patients compared with healthy volunteers. Of the plasma chemokines, only CXCL10 was increased by IFN-beta treatment; CCL3, CCL4, CCL5 and CXCL9 were unaltered. CCR5 mRNA expression in blood mononuclear cells correlated with the expression of T-helper type 1 (Th1)-associated genes whereas CCR4 and CCR7 mRNA expression correlated with Th2 and immunoregulatory genes. In conclusion, IFN-beta treatment caused 'steady-state' increases of several chemokine receptors relevant for CD4(+) T-lymphocyte trafficking and function, possibly facilitating lymphocyte migration into the CNS. An important therapeutic effect of IFN-beta treatment may be the normalization of a decreased Th2-related CD4(+) T-cell CCR4 expression in MS patients. Surface chemokine receptor expression and CXCL10 varied according to the timing of blood sampling in relation to the most recent IFN-beta injection. Thus, it is imperative to distinguish acute effects of IFN-beta from steady-state effects.

Adult↗

Association between an interleukin-13 promoter polymorphism and atopy.

Several studies indicate genetic involvement of Th2 cytokines in allergic diseases. Interleukin (IL)-13 has been mapped to the cytokine cluster on chromosome 5q31-33, which has been associated with atopic conditions. Recently, an association was reported between the T allele in a promoter polymorphism in the IL-13 gene (C to T exchange) at position -1055 and allergic asthma in a population study in the Netherlands. This observation was apparently confirmed in a case-control study using probands and spouses from a Dutch asthma family study, but the polymorphism in that study was reported to occur at position -1111. In the present study, we established that this polymorphism is located at position -1024 relative to the ATG translation initiation codon, and investigated whether it confers a genetic predisposition to atopic conditions and the Th1 condition multiple sclerosis (MS) in Caucasian subjects. We confirmed the association between the IL-13 -1024TT genoype and inhalation allergy (P = 2.4E-02). By combining the data from the three studies, we demonstrated a strong association (P = 1.09E-05) between the IL-13 -1024 marker and inhalation allergy. Furthermore, we showed for the first time that this association also exists in atopic dermatitis (P = 2.0E-02). No association with MS was found.

Base Sequence↗

A genome-wide screen for linkage in Nordic sib-pairs with multiple sclerosis.

Genetic factors influence susceptibility to multiple sclerosis but the responsible genes remain largely undefined, association with MHC class II alleles being the only established genetic feature of the disease. The Nordic countries have a high prevalence of multiple sclerosis, and to further explore the genetic background of the disease, we have carried out a genome-wide screen for linkage in 136 sibling-pairs with multiple sclerosis from Denmark, Finland, Norway and Sweden by typing 399 microsatellite markers. Seventeen regions where the lod score exceeds the nominal 5% significance threshold (0.7) were identified-1q11-24, 2q24-32, 3p26.3, 3q21.1, 4q12, 6p25.3, 6p21-22, 6q21, 9q34.3, 10p15, 10p12-13, 11p15.5, 12q21.3, 16p13.3, 17q25.3, 22q12-13 and Xp22.3. Although none of these regions reaches the level of genome-wide significance, the number observed exceeds the 10 that would be expected by chance alone. Our results significantly add to the growing body of linkage data relating to multiple sclerosis.

Denmark↗

Intravenous immunoglobulin G for the treatment of relapsing-remitting multiple sclerosis: a meta-analysis.

Intravenous immunoglobulin (IVIG) has several effects on the immune system that could have a beneficial influence on disease processes in multiple sclerosis (MS). Four double-blind trials in relapsing-remitting MS have demonstrated that IVIG may reduce the relapse rate, progression and the number of gadolinium-enhancing lesions. However, these trials were smaller than the pivotal trials of interferon-beta and glatiramer acetate, and therefore, we performed a meta-analysis of the four trials in order to provide an overall assessment of the benefits of IVIG in relapsing-remitting multiple sclerosis in comparison with other drugs currently available for treatment of disease activity in MS. The meta-analysis showed a significant beneficial effect on the annual relapse rate (effect size -0.5; P = 0.00003), on the proportion of relapse-free patients (0.29 difference; P = 2.1 x 10(-8)), change in Expanded Disability Status Scale (EDSS) score (effect size: 0.25; P = 0.04), and a trend towards a reduction in the proportion of patients who deteriorated (P = 0.03). Each single study in the meta-analysis had its weaknesses, but all studies were positive regarding their primary end-point, and the results yield concordant evidence for reduction of relapse rate and progression. The ideal dosage of IVIG for treating MS needs still to be determined. In conclusion, IVIG may be a valuable alternative for treatment of relapsing-remitting MS, but can presently not be considered as a first-line treatment. IVIG could be considered in patients who do not tolerate or are unwilling to take the approved injectable medications, but additional studies are needed to establish the role of IVIG in the management of multiple sclerosis.

Persons with Disabilities↗

Disease severity in Danish multiple sclerosis patients evaluated by MRI and three genetic markers (HLA-DRB1*1501, CCR5 deletion mutation, apolipoprotein E).

As the understanding of the autoimmune inflammatory response in multiple sclerosis (MS) expands, polymorphic genes involved in this process become possible candidates that may determine the severity of disease. Therefore, three candidate genes DRB1*1501, CCR5 and apolipoprotein E (APOE) were examined in a population-based patient sample (n = 70) to assess an association between disease progression measured by clinical disability and MRI parameters. The total lesion area (TLA) on T2-weighted images was measured with a semi-automated threshold technique. Patients with the CCR5delta32 allele showed a non-significant trend towards a smaller lesion burden (TLA/years duration), but were not associated to a milder EDSS/years duration. Our data support previous assumptions of a modulation of severity in MS by the CCR5delta32 genotype, which may convey less inflammation and tissue destruction. Carriers of the DRB1*1501 and APOE-epsilon4 allels did not reveal more severe disease progression, neither by the EDSS/years of duration nor by the TLA/years duration. This study was performed on a population-based sample in a genetically homogeneous Danish population but, due to the limited number of patients examined, weak associations between candidate genes and disease variables cannot be excluded.

Adult↗

Linkage analysis suggests a region of importance for multiple sclerosis in 3p14-13.

Four genomic screens for linkage in multiple sclerosis (MS) have been reported. They confirmed the established role of the human leucocyte antigen (HLA) complex genes in MS and, in addition, suggested the importance of a few other chromosomal segments. Here we report evidence for the importance of 3p14-13 region identified by suggestive linkage in genomic screens from Canada and the United Kingdom. When studying 146 Nordic MS multiplex families, mostly affected sib-pairs, with eight microsatellite markers, spanning a 36-cM region, we observed a two-point non-parametric linkage (NPL) score of 2.39 (P = 0.007) by the GENEHUNTER package for marker D3S1285 and a multipoint NPL score of 1.20 in the same region. Association studies in Swedish MS patients revealed modest allelic associations of uncertain significance not supported by transmission analysis. Analysis of the trinucleotide repeat sequence of the SCA7 gene in Swedish index cases did not reveal expansions. We conclude that support was obtained for the location of a gene or genes with importance for MS susceptibility in 3p14-13 region.

Alleles↗

Linkage analysis of a candidate region in Scandinavian sib pairs with multiple sclerosis reveals linkage to chromosome 17q.

To date, four genome screens have been completed in the demyelinating autoimmune disease multiple sclerosis (MS). Although these screens failed to identify any loci with major effects on susceptibility, several novel regions of potential linkage were suggested, including the long arm of chromosome 17. In order to further pursue this promising region we have investigated six highly polymorphic microsatellite markers in 115 Scandinavian families with MS affected sib pairs. Multipoint linkage analysis revealed a peak maximum likelihood score (MLS) of 0.9 in the region of marker D17S787. Stratifying the results on the basis of HLA-DR2 status showed that the linkage was not limited to families segregating for the HLA-DR2 allele as has previously been suggested. In conclusion, our results further support the proposal that a multiple sclerosis susceptibility locus is contained on chromosome 17q.

Chromosomes, Human, Pair 17↗

Linkage and association analysis of susceptibility regions on chromosomes 5 and 6 in 106 Scandinavian sibling pair families with multiple sclerosis.

In the genetically homogeneous Scandinavian population, we have investigated chromosome 5 and the HLA (human leukocyte antigen) region on chromosome 6p21 by applying linkage and association analyses on 106 white sibling pair families with multiple sclerosis. The importance of genes within the HLA region for the susceptibility of multiple sclerosis has previously been reported. More recently, findings have suggested importance of regions on chromosome 5. Half of chromosome 5 was analyzed by using 14 microsatellite markers and a susceptibility region with a maximum LOD score of 1.1 was identified. Chromosome 6 was analyzed by HLA-DR typing and using the TNF alpha microsatellite marker. A peak maximum LOD score of 2.0 was found at the HLA-DR marker. Association studies were made for all the markers, comparing 106 probands from the sibling pairs with 100 unrelated controls. None of the markers on chromosome 5 showed significant association with multiple sclerosis, whereas strong association between multiple sclerosis and DR2 was found, with an odds ratio of 3.7 (p < 10(-5)). It is surprising that association was not seen for any of the TNF alpha alleles including the 121-bp allele, although this allele was in positive linkage disequilibrium with DR2 in both patients and controls. Our results support the existence of multiple sclerosis susceptibility loci on chromosomes 5p and 6p21.

Chromosome Mapping↗

Intravenous immunoglobulin G reduces MRI activity in relapsing multiple sclerosis.

We wanted to assess whether intravenous immunoglobulin G (IVIG) decreases disease activity on MRI in relapsing MS. Previous trials of IVIG in relapsing-remitting MS demonstrated a reduction of acute relapses, but these studies did not include MRI. We treated 26 patients in a randomized, double-blind, crossover study of IVIG 1 g/kg daily or placebo on 2 consecutive days every month during two 6-month treatment periods. The primary end point was the number of gadolinium-enhancing lesions on monthly serial MRI. Secondary efficacy variables were the occurrence of exacerbations, clinical neurologic ratings, total MS lesion load on T2-weighted MRI, and multimodal evoked potentials. Eighteen patients completed the entire trial; eight patients did not. Twenty-one patients completed the first treatment period and at least two MRI examinations in the second treatment period and were included in the intention-to-treat analysis. On serial MRI, we observed fewer enhancing lesions per patient per scan during IVIG treatment (median, 0.4; range, 0 to 9.3) than during placebo treatment (median, 1.3; range, 0.2 to 25.7; p = 0.03). During IVIG treatment, 15 patients were exacerbation free compared with only 7 on placebo (p = 0.02). The total number of exacerbations in the IVIG period was 11 and in the placebo period, 19 (not significant). None of the remaining secondary efficacy measures were significantly different between the two treatment periods. The number of adverse events, in particular eczema, was significantly higher during IVIG therapy than during placebo treatment. These results suggest that IVIG treatment is beneficial to patients with relapsing MS.

Adolescent↗

Cerebrospinal fluid bombesin and calcitonin in patients with central nervous system metastases from small-cell lung cancer.

To determine whether levels of mammalian bombesin (MB) or calcitonin would be useful in detecting CNS metastases in patients with small-cell lung cancer (SCLC), we measured their concentrations in the CSF of 94 patients who underwent lumbar puncture for suspected CNS involvement. The MB concentration was significantly elevated in the 51 patients with definite CNS metastases as compared with the 30 patients without apparent CNS involvement (P less than .01). This significance was due to increased levels of MB in 18 patients with meningeal carcinomatosis. Whereas CSF MB was detectable (greater than 10 fmol/mL) in only 7% of patients without apparent CNS involvement, CSF MB was detectable in 21% with parenchymal CNS metastases and in 78% of those with meningeal carcinomatosis. Interestingly, 93% of patients having MB concentrations above 20 fmol/mL had meningeal metastases. The calcitonin concentration was significantly elevated in 42 patients with CNS metastases as compared with 27 patients without CNS involvement (P less than .01). Both the 15 patients with meningeal carcinomatosis and the 27 patients with only parenchymal metastases had significantly elevated levels of CSF calcitonin as compared with those without CNS metastases. Fifty-three percent of patients with meningeal carcinomatosis and 48% with parenchymal metastases had a CSF calcitonin level above 18 fmol/mL, whereas only 7% without apparent CNS metastases exceeded this level. Sixty-seven percent of all patients with CNS metastases had increased CSF levels of one of the two hormonal markers. Thus, in SCLC patients, an elevated CSF calcitonin strongly suggested CNS metastases and an elevated MB was very suggestive of the presence of meningeal carcinomatosis. However, only the latter observation seems of clinical importance due to the difficulties in establishing this diagnosis with current diagnostic measures.

Bombesin↗

Syphilitic normal pressure hydrocephalus.

We report a case of presenile dementia with radiological and cisternographical features suggesting normal pressure hydrocephalus, caused by syphilitic infection. Treatment with penicillin resulted in considerable regression of the neurological and psychological signs.

Brain↗

Acetylsalicylic acid in the prevention of stroke in patients with reversible cerebral ischemic attacks. A Danish cooperative study.

Two hundred and three patients, 148 males and 55 females, who during the last month before admission had experienced at least one reversible cerebral ischemic attack of less than 72 hours duration, were randomly assigned to treatment with either acetylsalicylic acid (ASA) 1000 mg daily (101 patients) or placebo (102 patients). The average follow-up period was 25 months. The two treatment groups were comparable with respect to age, sex, associated diseases, risk factors, number and duration of cerebral ischemic attacks. No statistically significant differences were found between the treatment groups as to the primary end point: stroke or death (ASA group 20.8%, placebo group 16.7%). Occurrence of transient ischemic attacks during the treatment period was not reduced by ASA treatment, whereas there was a trend suggesting fewer myocardial infarctions in the ASA group (5.9%) than in the placebo group (13.7%). The difference, however, was not statistically significant (p = 0.10). We were thus unable to demonstrate any favorable influence of ASA 1000 mg daily in patients with reversible ischemic attacks. This study does not, of course, prove that ASA treatment is ineffective in stroke prevention.

Adult↗