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| 2. |
- Vikström, Linnea, et al.
(författare)
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Vaccine-induced correlate of protection against fatal COVID-19 in older and frail adults during waves of neutralization-resistant variants of concern : an observational study
- 2023
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Ingår i: The Lancet Regional Health. - : Elsevier. - 2666-7762. ; 30
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: To inform future preventive measures including repeated vaccinations, we have searched for a clinically useful immune correlate of protection against fatal COVID-19 among nursing homes residents.METHODS: We performed repeated capillary blood sampling with analysis of S-binding IgG in an open cohort of nursing home residents in Sweden. We analyzed immunological and registry data from 16 September 2021 to 31 August 2022 with follow-up of deaths to 30 September 2022. The study period included implementation of the 3rd and 4th mRNA monovalent vaccine doses and Omicron virus waves.FINDINGS: A total of 3012 nursing home residents with median age 86 were enrolled. The 3rd mRNA dose elicited a 99-fold relative increase of S-binding IgG in blood and corresponding increase of neutralizing antibodies. The 4th mRNA vaccine dose boosted levels 3.8-fold. Half-life of S-binding IgG was 72 days. A total 528 residents acquired their first SARS-CoV-2 infection after the 3rd or the 4th vaccine dose and the associated 30-day mortality was 9.1%. We found no indication that levels of vaccine-induced antibodies protected against infection with Omicron VOCs. In contrast, the risk of death was inversely correlated to levels of S-directed IgG below the 20th percentile. The death risk plateaued at population average above the lower 35th percentile of S-binding IgG.INTERPRETATION: In the absence of neutralizing antibodies that protect from infection, quantification of S-binding IgG post vaccination may be useful to identify the most vulnerable for fatal COVID-19 among the oldest and frailest. This information is of importance for future strategies to protect vulnerable populations against neutralization resistant variants of concern.FUNDING: Swedish Research Council, SciLifeLab via Knut and Alice Wallenberg Foundation, VINNOVA. Swedish Healthcare Regions, and Erling Persson Foundation.
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| 3. |
- Amin, Kawa, et al.
(författare)
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Evidence for eosinophil and IL-17 mediated inflammation in allergic rhinitis
- 2020
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Ingår i: Clinical and Molecular Allergy. - : Springer Science and Business Media LLC. - 1476-7961. ; 18
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Tidskriftsartikel (refereegranskat)abstract
- Background: The aim was to determine the level of inflammatory cytokines, eosinophil cationic protein and IgE in allergic rhinitis (AR) patients.Subjects and methods: Blood samples were taken from 88 AR patients and 88 healthy controls (HC). Each sample was analysed for eosinophil counts by flow cytometry, IgE by ECLIA, ECP, IL-17, and IL-33 by using ELISA test.Results: There was no significant difference between AR patients and the control group in age and gender. Levels of eosinophils, IgE, ECP, IL-17, IL-33 and the total symptom scores were significantly higher in AR patients than the HC (P = 0.0001). Serum ECP correlated with IL-17 (P = 0.041, r = 0.42), IL-33 (P = 0.0001, r = 080), and IgE levels (P = 0.017, r = 0.45) in the R patients. There was no correlation between IL-17 and IL-33. There was a correlation between symptom scores and eosinophils (P = 0.026, r = 0.52), and IgE (P = 0.001, r = 0.60) in the patients. No correlation was observed between symptom scores and ECP, IL-17, and IL-33 in the AR patient.Conclusions: Patients with AR have significant higher serum levels of ECP, IL-17, and IL-33 than healthy controls. This indicates that these markers could be used to in order to diagnose AR and to monitor disease. Inhibitory molecules to IL-17 and IL-33 may be considered as novel treatment strategies.
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| 4. |
- Amin, Kawa, et al.
(författare)
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Hepatic Immune Response to Environmental Carcinogens
- 2018
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Ingår i: Pharmacognosy Magazine. - : EManuscript Technologies. - 0973-1296 .- 0976-4062. ; 14:58, s. 548-553
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Tidskriftsartikel (refereegranskat)abstract
- Aim: Environmental carcinogenic substances contribute to increasing incidence of hepatocellular carcinoma (HCC). We employed a sensitive method for the detection of DNA damage combined with analysis of the immune response to gain better knowledge how environmental carcinogens mediate pathology.Materials and Methods: Rat hepatocytes were isolated and stimulated with carcinogenic substances for the assessment of DNA damage. The mycotoxin aflatoxin B-1 (AFB(1)), two heterocyclic amines from the cooking of meat amino-3-methylimidazo[4,5-f] quinoline (IQ) and 3-amino-1-methyl-5H-pyr ido-(4,3-b)-indole (TRP-P-2), and protein extract from the fungus Lactarius necator were assayed. Unscheduled DNA synthesis in hepatocytes was measured by the incorporation of radioactive thymidine during DNA repair. Stimulation of hepatocyte/immune cell preparation with the substances and measurement of IFN gamma release at different time points determined their ability to induce an inflammatory response.Results: DNA repair in the hepatocytes was induced in response to 10(-7) M AFB(1) and 10(-9) M IQ. TRP-P-2 did not induce DNA repair; however, at 10(-4) M, the fungus extract did this. Furthermore, liver-resident immune cells responded with differential production of IFN gamma over time in response to stimulation by all the carcinogens, with AFB(1) being the most potent. TRP-P-2 showed the most significant reduction in IFN gamma response over time.Conclusion: DNA damage in hepatocytes induced by environmental substances was detected at low molecular concentrations. The system did provide novel evidence for hepatic carcinogenicity by the fungus L. necator. Analysis of the response by liver-resident immune cells to the substances suggested that highly mutagenic substances induce prolonged inflammatory response.
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| 5. |
- Byström, Jonas, et al.
(författare)
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Analysing the eosinophil cationic protein - a clue to the function of the eosinophil granulocyte
- 2011
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Ingår i: Respiratory Research. - : Springer Science and Business Media LLC. - 1465-9921 .- 1465-993X. ; 12, s. 10-
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Forskningsöversikt (refereegranskat)abstract
- Eosinophil granulocytes reside in respiratory mucosa including lungs, in the gastro-intestinal tract, and in lymphocyte associated organs, the thymus, lymph nodes and the spleen. In parasitic infections, atopic diseases such as atopic dermatitis and asthma, the numbers of the circulating eosinophils are frequently elevated. In conditions such as Hypereosinophilic Syndrome (HES) circulating eosinophil levels are even further raised. Although, eosinophils were identified more than hundred years ago, their roles in homeostasis and in disease still remain unclear. The most prominent feature of the eosinophils are their large secondary granules, each containing four basic proteins, the best known being the eosinophil cationic protein (ECP). This protein has been developed as a marker for eosinophilic disease and quantified in biological fluids including serum, bronchoalveolar lavage and nasal secretions. Elevated ECP levels are found in T helper lymphocyte type 2 (atopic) diseases such as allergic asthma and allergic rhinitis but also occasionally in other diseases such as bacterial sinusitis. ECP is a ribonuclease which has been attributed with cytotoxic, neurotoxic, fibrosis promoting and immune-regulatory functions. ECP regulates mucosal and immune cells and may directly act against helminth, bacterial and viral infections. The levels of ECP measured in disease in combination with the catalogue of known functions of the protein and its polymorphisms presented here will build a foundation for further speculations of the role of ECP, and ultimately the role of the eosinophil.
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| 6. |
- Byström, Johan, et al.
(författare)
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Bounds and numerical results for the homogenized degenerated p-Poisson equation
- 2004
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Ingår i: Applications of Mathematics. - 0862-7940 .- 1572-9109. ; 49:2, s. 111-122
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Tidskriftsartikel (refereegranskat)abstract
- In this paper we derive upper and lower bounds on the homogenized energy density functional corresponding to degenerated p-Poisson equations. Moreover, we give some non-trivial examples where the bounds are tight and thus can be used as good approximations of the homogenized properties. We even present some cases where the bounds coincide and also compare them with some numerical results.
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| 7. |
- Byström, Jonas, 1969-
(författare)
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Eosinophil Cationic Protein : Expression Levels and Polymorphisms
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The eosinophil cationic protein (ECP) is usually associated with the eosinophil granulocyte. In this thesis the presence and production of this protein has been studied in two other cells. The circulating monocyte was found to contain ECP mRNA and small amounts of ECP, one thousand times less than that found in the eosinophil. The production decreased by differentiation of the myelomonoblastic cell line U937 into a macrophage phenotype. Submucosal lung macrophages did not stain for ECP and alveolar macrophages did not contain ECP mRNA. The circulating neutrophil contains ECP at a level hundred fold less than the eosinophil. We found that the protein is located to the primary granules of the neutrophil but could detect no ECP mRNA in the cell. It was shown in vitro that the protein was taken up by the cell and partly transported to the primary granules. The uptake did not seem to be receptor mediated. Upon stimulation of the neutrophils, ECP previously taken up, was re-secreted. The ECP protein is heterogeneous both to molecular characteristics and to function. To evaluate if a genetic component is involved, the ECP gene was analysed in 70 individuals. Three single nucleotide polymorphisms (SNP´s) were found, denoted 277(C>T), 434(G>C) and 562(G>C). The two first were located to the mature peptide-coding region and would change the amino acids, arg45cys and arg97thr. The prevalence of the most common SNP, 434, was evaluated in two eosinophil-related diseases, allergy/asthma and Hodgkin Lymphoma (HL). Forty-three HL patients were evaluated and it was found that the 434GG was significantly more prevalent in patients having nodular sclerosis (NS) as compared to other histologies (p=0.03). Erythrocyte sedimentation rate was also related to the 434GG genotype (p=0.009). In 209 medical students 434GG was more common (p=0.002) in those who indicated allergy. The genotype was unrelated to the production of IgE antibodies to allergens. In analysis of 76 subjects with asthma it was found that the 434GG genotype was significantly more common among allergic asthmatics (p=0.04). Asthma and HL-NS are characterized by fibrosis and eosinophils and ECP has been suggested in fibrosis development.
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| 8. |
- Byström, Jonas, et al.
(författare)
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Eosinophil cationic protein is stored in, but not produced by, peripheral blood neutrophils
- 2002
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Ingår i: Clinical and Experimental Allergy. - : Wiley. - 0954-7894 .- 1365-2222. ; 32:7, s. 1082-1091
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Eosinophil cationic protein (ECP) is an eosinophil-derived protein, which has been shown to be present in circulating neutrophils. OBJECTIVE: To establish whether ECP is produced or internalized by peripheral blood neutrophils. METHODS: This was done using microscopy, flow cytometry, fractionation of cells and RT-PCR techniques. RESULTS: No ECP mRNA was detected after extensive cell purification to eliminate all traces of contaminating eosinophils. Examination of immunostained neutrophils by light, confocal, electron microscopy together with cell fraction experiments, established that ECP is present intracellularly and is mostly associated to cell granules. Uptake studies by flow cytometry and by using both cold and radiolabelled ECP showed that it is internalized by neutrophils and stored in some proportion in their primary granules. Upon stimulation with serum-treated Sephadex particles, the internalized ECP was partially released from cells. CONCLUSION: ECP is not produced but can be internalized by circulating neutrophils, which take it from the environment and partially store it in their primary granules.
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| 10. |
- Byström, Jonas, et al.
(författare)
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Inducible CYP2J2 and its product 11,12-EET promotes bacterial phagocytosis : a role for CYP2J2 deficiency in the pathogenesis of Crohn's disease?
- 2013
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Ingår i: PLOS ONE. - : Public Library of Science. - 1932-6203. ; 8:9
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Tidskriftsartikel (refereegranskat)abstract
- The epoxygenase CYP2J2 has an emerging role in inflammation and vascular biology. The role of CYP2J2 in phagocytosis is not known and its regulation in human inflammatory diseases is poorly understood. Here we investigated the role of CYP2J2 in bacterial phagocytosis and its expression in monocytes from healthy controls and Crohns disease patients. CYP2J2 is anti-inflammatory in human peripheral blood monocytes. Bacterial LPS induced CYP2J2 mRNA and protein. The CYP2J2 arachidonic acid products 11,12-EET and 14,15-EET inhibited LPS induced TNFα release. THP-1 monocytes were transformed into macrophages by 48h incubation with phorbol 12-myristate 13-acetate. Epoxygenase inhibition using a non-selective inhibitor SKF525A or a selective CYP2J2 inhibitor Compound 4, inhibited E. coli particle phagocytosis, which could be specifically reversed by 11,12-EET. Moreover, epoxygenase inhibition reduced the expression of phagocytosis receptors CD11b and CD68. CD11b also mediates L. monocytogenes phagocytosis. Similar, to E. coli bioparticle phagocytosis, epoxygenase inhibition also reduced intracellular levels of L. monocytogenes, which could be reversed by co-incubation with 11,12-EET. Disrupted bacterial clearance is a hallmark of Crohn's disease. Unlike macrophages from control donors, macrophages from Crohn's disease patients showed no induction of CYP2J2 in response to E. coli. These results demonstrate that CYP2J2 mediates bacterial phagocytosis in macrophages, and implicates a defect in the CYP2J2 pathway may regulate bacterial clearance in Crohn's disease.
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