| 1. |
- Bolin, Karin, et al.
(författare)
-
Association of STAT4 Polymorphism with Severe Renal Insufficiency in Lupus Nephritis
- 2013
-
Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 8:12, s. 84450-
-
Tidskriftsartikel (refereegranskat)abstract
- Lupus nephritis is a cause of significant morbidity in systemic lupus erythematosus (SLE) and its genetic background has not been completely clarified. The aim of this investigation was to analyze single nucleotide polymorphisms (SNPs) for association with lupus nephritis, its severe form proliferative nephritis and renal outcome, in two Swedish cohorts. Cohort I (n = 567 SLE cases, n = 512 controls) was previously genotyped for 5676 SNPs and cohort II (n = 145 SLE cases, n = 619 controls) was genotyped for SNPs in STAT4, IRF5, TNIP1 and BLK. Case-control and case-only association analyses for patients with lupus nephritis, proliferative nephritis and severe renal insufficiency were performed. In the case-control analysis of cohort I, four highly linked SNPs in STAT4 were associated with lupus nephritis with genome wide significance with p = 3.7x10(-9), OR 2.20 for the best SNP rs11889341. Strong signals of association between IRF5 and an HLA-DR3 SNP marker were also detected in the lupus nephritis case versus healthy control analysis (pless than0.0001). An additional six genes showed an association with lupus nephritis with pless than0.001 (PMS2, TNIP1, CARD11, ITGAM, BLK and IRAK1). In the case-only meta-analysis of the two cohorts, the STAT4 SNP rs7582694 was associated with severe renal insufficiency with p = 1.6x10(-3) and OR 2.22. We conclude that genetic variations in STAT4 predispose to lupus nephritis and a worse outcome with severe renal insufficiency.
|
|
| 2. |
- Lindblom, Pontus, et al.
(författare)
-
Determining factors for successful vaccination against tick-borne encephalitis virus in older individuals
- 2014
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- We performed a cross-sectional study including 533 persons (median age 61) from the highly TBE endemic Åland Islands in the archipelago between Sweden and Finland. Blood samples, questionnaires and vaccination records were obtained from all study participants. The aim was to investigate if there was any association between TBEV antibody titer and 14 healthrelated factors: [age, gender, number of vaccine doses (0-5), time since last vaccine dose, previous TBE disease, vaccination against other flaviviruses, ≥2 tick-bites during the previous 3 months, pet-ownership, asthma, smoking, allergy, diabetes, medication, and previous tumor]. Measurement of TBEV IgG antibodies was performed using two commercial ELISA assays (Enzygnost and Immunozym), and a third in-house rapid fluorescent focus inhibition test was used to measure TBEV neutralizing antibodies. The age of the person and the number of vaccine doses were the two most important factors determining successful vaccination. The response to each vaccine dose declined linearly with increased age. A 35 year age difference corresponds to a vaccine dose increment from 3 to 4 to achieve the same response. Participants receiving medication and participants previously vaccinated against other flaviviruses had lower TBEV antibody titers on average, while those with self-reported asthma had higher titers. By comparing the 3 serological assays we show that the Enzygnost and Immunozym assay differ due to choice of cutoffs, but not in overall accuracy.
|
|
| 3. |
- Lindblom, Pontus, et al.
(författare)
-
Factors Determining Immunological Response to Vaccination against Tick-Borne Encephalitis Virus in Older Individuals
- 2014
-
Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 9:6, s. e0100860-
-
Tidskriftsartikel (refereegranskat)abstract
- We performed a cross-sectional study including 533 individuals (median age 61) from the highly TBE endemic A land Islands in the archipelago between Sweden and Finland. Blood samples, questionnaires and vaccination records were obtained from all study participants. The aim was to investigate if there was any association between TBEV antibody titer and 12 health-related factors. Measurement of TBEV IgG antibodies was performed using two commercial ELISA assays (Enzygnost and Immunozym), and a third in-house rapid fluorescent focus inhibition test was used to measure TBEV neutralizing antibodies. The age of the individual and the number of vaccine doses were the two most important factors determining the immunological response to vaccination. The response to each vaccine dose declined linearly with increased age. A 35 year age difference corresponds to a vaccine dose increment from 3 to 4 to achieve the same immunological response. Participants previously vaccinated against other flaviviruses had lower odds of being seropositive for neutralizing TBEV antibodies on average, while participants with self-reported asthma had higher odds of being seropositive. By comparing the 3 serological assays we show that the Enzygnost and Immunozym assay differ due to choice of cutoffs, but not in overall accuracy.
|
|
| 4. |
- Sjöwall, Johanna
(författare)
-
Clinical and Immunological Aspects of Lyme borreliosis
- 2011
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Lyme borreliosis (LB) is a tick-borne infection caused by spirochetes of the Borrelia (B.) burgdorferi sensu lato complex. The infection is associated with several clinical features, of which erythema migrans (EM) and neuroborreliosis (NB) are the most common in Europe. The prognosis after antibiotic therapy is generally good. However, some patients may have residual symptoms post-treatment. The cause of the delayed convalescence is unclear. There are several factors that may affect the clinical outcome of LB, for example, the early interaction between the host’s immune response and B. burgdorferi, the spirochete genotype, antibiotic therapy, as well as the host’s vulnerability.This thesis aimed to explore the type of early immune response that is generated to B. burgdorferi and its importance for the clinical outcome of LB, and to study the condition of persistent symptoms post-NB from clinical, immunological and diagnostic perspectives. In total, 125 adult patients with different clinical features and outcomes of LB and 23 healthy controls were included.In a prospective follow-up study of EM, we confirmed that the prognosis of EM is good after antibiotic therapy, and that B. afzelii is the most common B. burgdorferi genotype associated with EM in the Nordic countries. Seven patients (8%) reported persistent symptoms more than six months post-treatment. These patients had also a decreased early expression of inflammatory, Th1-type cytokines in the EM lesions, suggesting an importance of early, local Th1-type immunity to B. burgdorferi for a successful clinical outcome of LB. No correlation between clinical characteristics, allergic predisposition, B. burgdorferi genotype or serology and the development of symptoms post-treatment was found.Asymptomatic B. burgdorferi-seropositive individuals are interesting from clinical and immunological points of view, since they apparently have encountered B. burgdorferi without developing symptoms of LB. In this thesis, asymptomatic individuals were shown to display an enhanced innate inflammatory immune response to live B. garinii spirochetes, induced by dendritic cells and whole blood cells, in comparison with patients with a history of subacute NB and healthy controls. Whether this is the optimal immune response to B. burgdorferi remains to be determined.A randomized, placebo-controlled cross-over study showed that three weeks of doxycycline therapy did not significantly improve objective neurological signs, subjective symptoms or quality of life in NB patients with persistent symptoms post-treatment. Nor could any doxycycline-mediated effects on systemic cytokine responses be demonstrated.Brain magnetic resonance imaging (MRI) findings in NB patients with persistent symptoms post-treatment were shown to be nonspecific and to correlate with age, but not with the duration of symptoms.In conclusion, this thesis shows that there is an association between the early immune response to B. burgdorferi sensu lato and the clinical outcome of LB. The cause of prolonged convalescence post-treatment remains unknown and needs further investigation. However, repeated treatment with doxycycline does not lead to improvement of the persistent symptoms; nor does brain MRI facilitate diagnosis of, or provide an explanation for the post-treatment symptoms.
|
|
| 5. |
- Sjöwall, Johanna, et al.
(författare)
-
Decreased Th1-Type Inflammatory Cytokine Expression in the Skin Is Associated with Persisting Symptoms after Treatment of Erythema Migrans
- 2011
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 6:3, s. 0018220-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Despite the good prognosis of erythema migrans (EM), some patients have persisting symptoms of various character and duration post-treatment. Several factors may affect the clinical outcome of EM, e. g. the early interaction between Borrelia (B.) burgdorferi and the host immune response, the B. burgdorferi genotype, antibiotic treatment as well as other clinical circumstances. Our study was designed to determine whether early cytokine expression in the skin and in peripheral blood in patients with EM is associated with the clinical outcome. Methods: A prospective follow-up study of 109 patients with EM was conducted at the A land Islands, Finland. Symptoms were evaluated at 3, 6, 12 and 24 months post-treatment. Skin biopsies from the EM and healthy skin were immunohistochemically analysed for expression of interleukin (IL)-4, IL-10, IL-12p70 and interferon (IFN)-gamma, as well as for B. burgdorferi DNA. Blood samples were analysed for B. burgdorferi antibodies, allergic predisposition and levels of systemic cytokines. Findings: None of the patients developed late manifestations of Lyme borreliosis. However, at the 6-month follow-up, 7 of 88 patients reported persisting symptoms of diverse character. Compared to asymptomatic patients, these 7 patients showed decreased expression of the Th1-associated cytokine IFN-gamma in the EM biopsies (p = 0.003). B. afzelii DNA was found in 48%, B. garinii in 15% and B. burgdorferi sensu stricto in 1% of the EM biopsies, and species distribution was the same in patients with and without post-treatment symptoms. The two groups did not differ regarding baseline patient characteristics, B. burgdorferi antibodies, allergic predisposition or systemic cytokine levels. Conclusion: Patients with persisting symptoms following an EM show a decreased Th1-type inflammatory response in infected skin early during the infection, which might reflect a dysregulation of the early immune response. This finding supports the importance of an early, local Th1-type response for optimal resolution of LB.
|
|
| 6. |
- Sjöwall, Johanna, et al.
(författare)
-
Doxycycline-mediated effects on persistent symptoms and systemic cytokine responses post-neuroborreliosis: a randomized, prospective, cross-over study
- 2012
-
Ingår i: BMC Infectious Diseases. - : BioMed Central Ltd.. - 1471-2334. ; 12:186, s. 1-12
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Persistent symptoms after treatment of neuroborreliosis (NB) are well-documented, although the causative mechanisms are mainly unknown. The effect of repeated antibiotic treatment has not been studied in detail. The aim of this study was to determine whether: (1) persistent symptoms improve with doxycycline treatment; (2) doxycycline has an influence on systemic cytokine responses, and; (3) improvement of symptoms could be due to doxycycline-mediated immunomodulation.METHODS/DESIGN:15 NB patients with persistent symptoms ≥6 months post-treatment were double-blindly randomized to receive 200 mg of doxycycline or a placebo for three weeks. After a six-week wash-out period, a cross-over with a three-week course of a placebo or doxycycline was conducted. The primary outcome measures were improvement of persistent symptoms assessed by neurological examinations, a symptom severity score and estimation of the quality of life. The secondary outcome measure was changes in systemic cytokine responses.RESULTS:All 15 patients finished the study. No doxycycline-mediated improvement of post-treatment symptoms or quality of life was observed. Nor could any doxycycline-mediated changes in systemic cytokine responses be detected. The study was completed without any serious adverse events.DISCUSSION:No doxycycline-mediated improvement of post-treatment symptoms or quality of life was observed. Nor could any doxycycline-mediated changes in systemic cytokine responses be detected. The study was completed without any serious adverse events. To conclude, in this pilot study, doxycycline-treatment did not lead to any improvement of either the persistent symptoms or quality of life in post-NB patients. Accordingly, doxycycline does not seem to be the optimal treatment of diverse persistent symptoms post-NB. However, the results need to be confirmed in larger studies.
|
|
| 7. |
- Wang, Chuan, et al.
(författare)
-
Contribution of IKBKE and IFIH1 gene variants to SLE susceptibility
- 2013
-
Ingår i: Genes and Immunity. - : Springer Science and Business Media LLC. - 1466-4879 .- 1476-5470. ; 14:4, s. 217-222
-
Tidskriftsartikel (refereegranskat)abstract
- The type I interferon system genes IKBKE and IFIH1 are associated with the risk of systemic lupus erythematosus (SLE). To identify the sequence variants that are able to account for the disease association, we resequenced the genes IKBKE and IFIH1. Eighty-six single-nucleotide variants (SNVs) with potentially functional effect or differences in allele frequencies between patients and controls determined by sequencing were further genotyped in 1140 SLE patients and 2060 controls. In addition, 108 imputed sequence variants in IKBKE and IFIH1 were included in the association analysis. Ten IKBKE SNVs and three IFIH1 SNVs were associated with SLE. The SNVs rs1539241 and rs12142086 tagged two independent association signals in IKBKE, and the haplotype carrying their risk alleles showed an odds ratio of 1.68 (P-value=1.0 × 10−5). The risk allele of rs12142086 affects the binding of splicing factor 1 in vitro and could thus influence its transcriptional regulatory function. Two independent association signals were also detected in IFIH1, which were tagged by a low-frequency SNV rs78456138 and a missense SNV rs3747517. Their joint effect is protective against SLE (odds ratio=0.56; P-value=6.6 × 10−3). In conclusion, we have identified new SLE-associated sequence variants in IKBKE and IFIH1, and proposed functional hypotheses for the association signals.
|
|
| 8. |
- Wang, Chuan, et al.
(författare)
-
Genes identified in Asian SLE GWASs are also associated with SLE in Caucasian populations
- 2013
-
Ingår i: European Journal of Human Genetics. - : Nature Publishing Group: Open Access Hybrid Model Option B. - 1018-4813 .- 1476-5438. ; 21:9, s. 994-999
-
Tidskriftsartikel (refereegranskat)abstract
- Recent genome-wide association studies (GWASs) conducted in Asian populations have identified novel risk loci for systemic lupus erythematosus (SLE). Here, we genotyped 10 single-nucleotide polymorphisms (SNPs) in eight such loci and investigated their disease associations in three independent Caucasian SLE case–control cohorts recruited from Sweden, Finland and the United States. The disease associations of the SNPs in ETS1, IKZF1, LRRC18-WDFY4, RASGRP3, SLC15A4, TNIP1 and 16p11.2 were replicated, whereas no solid evidence of association was observed for the 7q11.23 locus in the Caucasian cohorts. SLC15A4 was significantly associated with renal involvement in SLE. The association of TNIP1 was more pronounced in SLE patients with renal and immunological disorder, which is corroborated by two previous studies in Asian cohorts. The effects of all the associated SNPs, either conferring risk for or being protective against SLE, were in the same direction in Caucasians and Asians. The magnitudes of the allelic effects for most of the SNPs were also comparable across different ethnic groups. On the contrary, remarkable differences in allele frequencies between Caucasian and Asian populations were observed for all associated SNPs. In conclusion, most of the novel SLE risk loci identified by GWASs in Asian populations were also associated with SLE in Caucasian populations. We observed both similarities and differences with respect to the effect sizes and risk allele frequencies across ethnicities.
|
|
