| 1. |
- Dzidic, Majda, et al.
(författare)
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Allergy development is associated with consumption of breastmilk with a reduced microbial richness in the first month of life
- 2020
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Ingår i: Pediatric Allergy and Immunology. - : WILEY. - 0905-6157 .- 1399-3038. ; 31, s. 250-257
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Tidskriftsartikel (refereegranskat)abstract
- Background Early colonization with a diverse microbiota seems to play a crucial role for appropriate immune maturation during childhood. Breastmilk microbiota is one important source of microbes for the infant, transferred together with maternal IgA antibodies. We previously observed that allergy development during childhood was associated with aberrant IgA responses to the gut microbiota already at 1 month of age, when the IgA antibodies are predominantly maternally derived in breastfed infants. Objective To determine the microbial composition and IgA-coated bacteria in breastmilk in relation to allergy development in children participating in an intervention trial with pre- and post-natal Lactobacillus reuteri supplementation. Methods A combination of flow cytometric cell sorting and 16S rRNA gene sequencing was used to characterize the bacterial recognition patterns by IgA in breastmilk samples collected one month post-partum from 40 mothers whose children did or did not develop allergic and asthmatic symptoms during the first 7 years of age. Results The milk fed to children developing allergic manifestations had significantly lower bacterial richness, when compared to the milk given to children that remained healthy. Probiotic treatment influenced the breastmilk microbiota composition. However, the proportions of IgA-coated bacteria, the total bacterial load and the patterns of IgA-coating were similar in breastmilk between mothers of healthy children and those developing allergies. Conclusion Consumption of breastmilk with a reduced microbial richness in the first month of life may play an important role in allergy development during childhood.
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| 2. |
- Svenvik, Maria, 1973-, et al.
(författare)
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Plasma oxylipin levels associated with preterm birth in preterm labor✰
- 2021
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Ingår i: Prostaglandins, Leukotrienes and Essential Fatty Acids. - : Elsevier. - 0952-3278 .- 1532-2823. ; 166
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Tidskriftsartikel (refereegranskat)abstract
- Introduction Preterm labor is a common clinical problem in obstetrics. Since the majority of women with preterm labor eventually deliver at full term, biomarkers are needed to more accurately predict who will deliver preterm. Oxylipins, given their importance in inflammation regulation, are highly interesting in this respect since labor is an inflammatory process.Methods Eighty women with preterm labor before 34 weeks of gestation were enrolled in a prospective observational multi-center cohort study. Oxylipin levels of 67 analytes in plasma samples were analyzed by liquid chromatography coupled to tandem mass spectrometry.Results Twenty-one (26%) of the women delivered before 34 weeks of gestation, and of those women, fourteen delivered within 48 h of admission. Logistic multivariate regression showed that lower levels of 9,10-DiHODE were associated with delivery before 34 weeks of gestation (aOR 0.12 (0.024–0.62)) and within 48 h ((aOR 0.13 (0.019–0.93)). Furthermore, higher levels of 11,12-DiHETrE were associated with delivery before 34 weeks of gestation ((aOR 6.19 (1.17–32.7)) and higher levels of 8-HETE were associated with delivery within 48 h ((aOR 5.01 (1.13–22.14)).Conclusions The oxylipin 9,10-DiHODE may be protective in preterm labor, both for delivery after 34 weeks of gestation and for delivery later than 48 h of admission, whereas 11,12-DiHETrE and 8-HETE display the opposite effect. Larger studies are needed to validate these mediators as biomarkers for prediction of preterm birth following preterm labor.
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| 3. |
- Svenvik, Maria, 1973-
(författare)
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Prediction of Spontaneous Preterm Birth : Clinical and Immunological Aspects
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Background: Preterm birth (PTB), defined as birth before 37 weeks of gestation, accounts for most neonatal death and morbidity. Accurate prediction is a pre-requisite for the prevention and proper management of PTB. However, methods for prediction are unsatisfactory, although sonographic cervical length has a moderate predictive value. For clinical utility, adding a biomarker could increase the predictive accuracy. The immune system has an important regulatory role during pregnancy. Thus, presumptive predictive biomarkers may be searched for among immune-related molecules, such as cytokines, chemokines and other inflammation-associated mediators. The aims of this thesis were to identify clinical risk factors and immunological prediction markers for PTB, both in women at increased risk of PTB because of preterm labour (PTL) or preterm prelabour rupture of the membranes (PPROM), and in asymptomatic women in early pregnancy. An additional aim was to explore immune reaction patterns in PTL and PPROM compared to normal pregnancy. Material and methods: In a retrospective registry study, including 20,643 women who delivered during a five-year period, risk factors for Apgar score <7 at five minutes and risk factors for PTB <32 weeks were investigated using univariate and multivariate logistic regression. Furthermore, in a multi-centre mixed case-control and prospective cohort study of women with PTL <34 weeks of gestation (n=80), PPROM (n=40), as well as antenatal controls (n=44) and controls in labour at term (n=40), plasma levels of cytokines and chemokines representing different types of immune responses were analysed with a multiplex bead assay. In addition, an extended protein analysis exploring 92 inflammation-associated plasma proteins using proximity extension assay (PEA) was performed, as well as analysis of 67 different oxylipins by liquid chromatography coupled to tandem mass spectrometry. Finally, the PEA technique was used also to explore plasma proteins in a case-control study including 46 women with PTB and 46 women with normal pregnancies and delivery at term. Results and conclusions: A number of partly preventable clinical risk factors for PTB <32 weeks were identified, for example smoking (odds ratio (OR) 1.61 (95% confidence interval (CI) 1.07-2.41)); preeclampsia (OR 5.48 (95% CI 3.39-8.86)); and multiple gestation (OR 15 (95% CI 10-24)). The most evident risk factor for low Apgar scores was PTB; the more preterm the higher the risk. This provides important information for health care professionals, and offers motivations for preventive strategies regarding smoking cessation. Both PTL and PPROM were associated with a more pro-inflammatory profile compared to antenatal controls, with an increase in CXCL1. In addition, PTL showed higher CCL17 levels, and PPROM showed higher IL-6 levels compared with normal pregnancy. The inflammatory profile was even higher in labour at term, reflected by higher levels of CXCL1, CXCL8, and IL-6 compared with PTL, probably due to the more advanced stage of the parturition process in these women. To identify women with PTL and subsequent PTB <34 weeks of gestation, we found that a combination of the proteins IL-6, IL-17C, IL-10RB, and FGF-23 strongly correlated with PTB <34 weeks with an area under the curve (AUC) of 0.90; inferring a sensitivity of 90%, and specificity of 74%. For the prediction of delivery within 48 hours in women with PTL, the combination of IL-6 and IL-17C displayed an AUC of 0.88, with a sensitivity of 100%, and a specificity of 71%. Additionally, plasma levels of oxylipins were associated with time of birth. Lower levels of 9,10-DiHODE were associated with PTB <34 weeks (adjusted (a) OR 0.12 (0.024-0.62)) and with delivery within 48 hours (aOR 0.13 (0.019-0.93)), while higher levels of 11,12-DiHETre were associated with delivery <34 weeks (aOR 6.19 (1.17-32.7)) and higher levels of 8-HETE were associated with delivery within 48 hours (aOR 5.01 (1.13-22.14)). In asymptomatic women, plasma levels of combinations of inflammation-associated proteins in the first and the second trimester also revealed predictive information regarding subsequent risk for PTB <34 weeks. Combining MMP10trim1, sCD40trim2, MCSFtrim2, Flt3Ltrim2, and FGF-21diff (diff= difference in protein levels comparing the first and second trimesters) provided a prediction model with an AUC of 0.90. Proteins from the first trimester exclusively (sCD40 and MMP10) rendered an AUC of 0.76. This work provides valuable knowledge in the field of PTB and PTL with useful information on risk factors for PTB. Important associations between levels of inflammation-associated proteins and oxylipins with PTB following PTL were found. Before these findings can have clinical implications, they need to be validated in other cohorts. Additionally, in order to be clinically useful as a prediction tool for PTB, a bedside test is needed. Since the PEA technique is PCR-based, this might be achievable. For prediction of PTB in early pregnancy, we have interesting findings with acceptable accuracy based on samples from both the first and the second trimesters. However, as preventive interventions for PTB are preferably initiated early in pregnancy, a prediction tool has better value if it is based on plasma samples from the first trimester. Therefore, we plan to extend this study and evaluate other potential protein biomarkers.
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| 4. |
- Ahlbeck, Lars, 1964-
(författare)
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Intralymphatic Immunotherapy : A Novel Route to Ameliorate Allergic Rhinitis Due to Pollen
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Allergy to pollen and animal dander is a major public health problem. Close to 30% of the population have symptoms from the upper and/or lower respiratory tract when they meet fur animals or pollen. Whereas symptom-relieving medications have a good to sufficient effect on about 80% of those affected, a large group of 10–20% have severe symptoms, despite medication, with an impact on well-being and ability to work. In Sweden, the annual cost of allergy was calculated at €1.3 billion in 2014.Immunotherapy is effective in treating and preventing pollen allergy and allergic asthma, but is expensive, complicated, requiring 40 injections, and takes more than three years to complete if subcutaneous injections are used. Tablets placed under the tongue are another method, with one tablet taken every day for three years. Only 1.5‰ receive such treatment, yet just over 3% would need it.With intralymphatic immunotherapy, a small dose of allergen is given in a lymph node in the groin on 3 occasions, one month apart. As this method takes only eight weeks, it is a much faster and less costly treatment. However, although several studies have shown that the treatment is safe, its efficacy remains the subject of doubt.Our pilot study in 2012, with a 3-year follow-up to 2015, showed encouraging results, and was followed by a double-blind randomised study with 72 participants from 2014 to 2018. The research subjects then received treatment with birch and grass pollen extract or one extract and a placebo. Regardless of treatment, symptoms, quality of life and medication consumption improved during the birch and grass pollen seasons in the 3 years after treatment. Increased frequencies of T-regulatory lymphocytes may explain the non-specific effects.In 2017 to 2018, we conducted a double-blind study with 38 participants, half of whom received placebo and half, active treatment. In this study, we saw no difference between the treatment groups in the first year after treatment. However, after discontinuation and unblinding in 2019, i.e., two years after treatment, the actively treated group improved in terms of symptoms, and quality of life was improved compared with the placebo group despite less need for medication. T-regulatory lymphocytes increased one year after treatment only in the actively treated group.A long-term follow-up of the research subjects from our two larger studies in 2022, i.e., five to eight years after treatment, showed in the double-blind study without a pure placebo that the scores for symptoms, medication use, and quality of life remained as low as after the first three years. In the placebo-controlled study, a statistically significant improvement in symptoms remained during the grass pollen season. Analysing the two studies together, symptom improvement was significant even during the birch pollen season. Thus, although the effect does not seem to diminish, those who did not receive birch, but only grass, needed to use more medication during the birch pollen season in 2022, seven to eight years after treatment. Moreover, those who did not receive grass but only birch needed more medication during the grass pollen season. This may suggest that the non-specific effect begins to wane after seven to eight years.Allergy to pollen is a major problem for individuals and society, where symptom-relieving treatment with drugs is not enough for many. They can be helped with immunotherapy, which takes at least three years, is expensive and fraught with side effects. In contrast, intralymphatic immunotherapy involves three injections over eight weeks. Our three studies show that the treatment is safe and indicate that it has a clinical effect up to eight years after treatment. T-regulatory cells appear to be important to the immunological mechanism, leading to tolerance to pollen.
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| 5. |
- Ahlbeck, Lars, 1964-, et al.
(författare)
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Intralymphatic immunotherapy with one or two allergens renders similar clinical response in patients with allergic rhinitis due to birch and grass pollen
- 2022
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Ingår i: Clinical and Experimental Allergy. - Chichester, United Kingdom : Wiley-Blackwell Publishing Inc.. - 0954-7894 .- 1365-2222. ; 52:6, s. 747-759
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Tidskriftsartikel (refereegranskat)abstract
- IntroductionThere is a need for a fast, efficient and safe way to induce tolerance in patients with severe allergic rhinitis. Intralymphatic immune therapy has been shown to be effective. MethodsPatients with severe birch and timothy allergy were randomized and received three doses of 0.1 ml of birch and 5-grass allergen extracts (10,000 SQ units/ml, ALK-Abello), or birch and placebo or 5-grass and placebo by ultrasound-guided injections into inguinal lymph nodes at monthly intervals. Rhinoconjunctivitis total symptom score, medication score and rhinoconjunctivitis quality of life questionnaire were evaluated before treatment and after each birch and grass pollen season during three subsequent years. Circulating proportions of T helper subsets and allergen-induced cytokine and chemokine production were analysed by flow cytometry and Luminex.Results The three groups reported fewer symptoms, lower use of medication and improved quality of life during the birch and grass pollen seasons each year after treatment at an almost similar rate independently of treatment with one or two allergens. Mild local pain was the most common adverse event. IgE levels to birch decreased, whereas birch-induced IL-10 secretion increased in all three groups. IgG4 levels to birch and timothy and skin prick test reactivity remained mainly unchanged. Conjunctival challenge tests with timothy extract showed a higher threshold for allergen. In all three groups, regulatory T cell frequencies were increased 3 years after treatment.Conclusions Intralymphatic immunotherapy with one or two allergens in patients with grass and birch pollen allergy was safe, effective and may be associated with bystander immune modulatory responses.
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| 6. |
- Bensberg, Maike, 1993-
(författare)
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DNA methylation in T cell leukaemia
- 2024
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- T cell acute lymphoblastic leukaemia (T-ALL) is a predominantly paediatric cancer that stems from malignant transformation of developing T cells. While the disease has an overall survival rate of 80%, the intense chemotherapy treatment causes severe toxicity and long-term side effects. Furthermore, the survival rate for patients in relapse is less than 25%. Consequently, there is a need for improved therapy options to reduce treatment-related side effects and improve the survival rate of relapsed patients. Targeting aberrant DNA methylation with hypomethylating agents (HMAs) has been successful in the treatment of myelodysplastic syndromes and acute myeloid leukaemia but has not been routinely used in the treatment of T-ALL, despite DNA hypomethylation being observed in T-ALL patients. In this work, we employed a comprehensive set of molecular and sequencing-based techniques to explore the possibilities of HMAs as a treatment option for T-ALL.We made the discovery that the DNA demethylating enzyme ten-eleven translocation 2, TET2, is downregulated or completely silenced in primary T-ALL. Moreover, the TET2 promoter was highly methylated in a group of patients, suggesting that TET2 itself can be silenced through DNA methylation in T-ALL. By treatment with HMAs, TET2 was demethylated in T-ALL cell lines and was one of few genes that was activated upon loss of DNA methylation, indicating that TET2 expression is regulated by DNA methylation in T-ALL cell lines. The development of a novel HMA, the DNMT1-specific inhibitor GSK-3685032, offers a tool to reveal the mechanism of action of the traditional HMAs, 5- azacytidine and decitabine, and to study the effects of acute loss of DNA methylation on cancer cells. We found that 5-azacytidine and decitabine are cytotoxic to T-ALL cells primarily by creating DNA double strand breaks. In contrast, GSK did not prompt a DNA damage response and instead reduced global DNA methylation to as little as 18% with limited cytotoxicity only occurring after levels of DNA methylation had dropped below 30%, a level of demethylation not achieved with DEC or AZA.T-ALL is more than two times more common in boys than girls and mutations in X-linked tumour suppressor genes that escape X inactivation, have been suggested as an underlying cause for the observed sex-bias. In theory, these aberrations would be more detrimental in XYmale cells than in XX-female cells due to the presence of an extra protective copy of the gene in females. We profiled DNA methylation during T cell development and created a map of sex-specific gene expression and expression from the inactive X chromosome, finding that some, but not all, suggested tumour suppressor genes in fact escape X inactivation. These results highlight the importance of profiling the healthy cells that T-ALL arises from to correctly judge the functional impact of gene dysregulation in cancer.In the last study, we aimed to investigate the role of N6-adenine methylation (6mdA) during T cell differentiation. While 6mdA is common in bacteria it is much rarer in humans. Nevertheless, 6mdA has previously been associated with several cellular processes, including cancer progression. Our study calls the presence of 6mdA in mammals into question by exposing limitations of the techniques used in its analysis. We show that contamination with bacterial DNA or 6mAcontaining RNA, nonspecific antibody binding, and low precision of third-generation sequencing techniques all hinder the detection and investigation of rare DNA modifications, such as 6mdA.Together, this work is an in-depth study of the function and the potential of DNA methylation in the biology of healthy and malignant T cells.
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| 7. |
- Bruno, Valentina, 1986-
(författare)
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Clinical and immunological aspects on recurrent pregnancy loss
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Paper I. Effects of low molecular weight heparin on the polarization and cytokine profile of macrophages and T helper cells in vitro. Sci Rep 2018. In paper I low molecular weight heparin (LMWH) in vitro effects on activation and polarization of central regulatory immune cells, such as Th cells and macrophages, were assessed, since LMWH has been widely used as an empiric treatment in recurrent pregnancy loss (RPL) and its immunological effects are not fully known. Isolated blood monocytes and T helper (Th) cells under different activation and polarizing conditions were cultured without or with LMWH at different concentrations. LMWH exposure induced an activated phenotype of macrophages, with high expression of HLA-DR and CD206 assessed by flow cytometry, associated with increased secretion of Th17-associated CCL20, and decreased secretion of CCL2 (M2-associated) and CCL22 (Th2), as measured by multiplex bead array. In accordance, LMWH exposure to Th cells reduced the proportion of CD25highFoxp3+ regulatory Tcells, and intensified IFN-γ secretion. Collectively, a mainly pro-inflammatory effect was noted on two essential tolerance-promoting cells, suggesting that potential immunological effects of LMWH may be effective mainly at an earlier gestational age to provide an appropriate implantation process in women with recurrent miscarriage. Paper II. Low-molecular-weight-heparin increases Th1- and Th17-associated chemokine levels during pregnancy in women with unexplained recurrent pregnancy loss: a randomized controlled trial. Sci Rep 2019.In paper II we investigated whether LMWH could modulate immune responses in vivo during pregnancy of women with unexplained RPL. A Swedish open multi-centre randomized controlled trial included 45 women treated with tinzaparin and 42 untreated women. Longitudinally collected plasma samples were obtained at gestational weeks (gw) 6, 18, 28 and 34 and analyzed by multiplex bead technology for levels of 11 cytokines and chemokines, chosen to represent inflammation and T-helper subset-associated immunity. LMWH-treated and untreated women showed differences during pregnancy of the Th1-associated chemokines CXCL10 (p = 0.01), CXCL11 (p < 0.001) and the Th17- associated chemokine CCL20 (p = 0.04), while CCL2, CCL17, CCL22, CXCL1, CXCL8, CXCL12, CXCL13 and IL-6 did not differ. Significantly higher plasma levels of CXCL10 and CXCL11 in treated women were detected at gw 28 and 34, compared to the untreated ones. Thus, a potential proinflammatory effect, linked mainly to Th1 immunity, was shown, suggesting an unfavorable effect of LMWH treatment, since Th1 responsea are responsible for breaking the fetal-maternal immune tolerance. Paper III. First-trimester trophoblasts obtained by chorionic villus sampling maintain tolerogenic and proteomic features in successful pregnancies despite a history of unexplained recurrent pregnancy loss. Am J Reprod Immunol. 2020.In paper III we investigate the “local” immune changes in women with RPL, since they potentially could reveal important mechanisms in RPL. Supernatants from superfluous chorionic villus sampling material culture was used in an ex vivo model, to determinate the immune proteomics profile and to perform functional assays for M2 like macrophages and regulatory T cells polarization, assessed by flow cytometry technique. Chorionic villi, human fetally derived placental tissue, were shown to induce an M2 like-phenotype and an expansion of Treg cells in an ex vivo model, and these immunological properties were maintained despite a history of RPL. Accordingly, no differences in the inflammation proteomic profile were found in RPL, compared to controls. Trophoblasts in an ex vivo model thus maintain tolerogenic and proteomic profile features in successful pregnancies, despite a history of RPL.
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| 8. |
- Ewerman, Lea, et al.
(författare)
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Immunomodulating Effects Depend on Prolactin Levels in Patients with Hyperprolactinemia
- 2020
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Ingår i: Hormone and Metabolic Research. - Stuttgart : Thieme Medical Publishers. - 0018-5043 .- 1439-4286. ; 52:04, s. 228-235
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Tidskriftsartikel (refereegranskat)abstract
- Prolactin is known to have immune modulatory effects acting through the prolactin receptor, which is present on a variety of immune cells. Certain chemokines contribute to form the type of T helper (Th) preponderance in the immune response. The objective of this work was to assess if hyperprolactinemia not related to pregnancy is associated with changes in circulating levels of chemokines and other immunological markers. In this cross sectional study, 35 patients with hyperprolactinemia (5 men), and 102 healthy blood donors (19 men) were included. Serum levels of Th1- Th2- and Th17-associated chemokines, C-reactive protein, immunoglobulins, and the B cell attracting chemokine CXCL13 were assessed. The hyperprolactinemic group had significantly higher levels of Th2 associated CCL22 (p=0.022), Th17 associated CXCL1 (p=0.001), B cell attracting CXCL13 (p=0.003), and C-reactive protein (p<0.001) compared to controls, and these proteins were also positively correlated with prolactin levels. While differences in CCL22, CXCL1, CXCL13, and C-reactive protein were present in patients with low or moderate hyperprolactinemia, no differences were observed at high (>3600 mU/l) prolactin levels. To evaluate a possible dose-associated response to prolactin, an in vitro model was used, showing prolactin-induced increase in T-helper cell activation at moderate levels, while activation decreased at higher levels. Hyperprolactinemia seems to have several immunomodulatory effects and was associated with increased levels of chemokines associated with Th2 and Th17 responses and B cell attraction. However, patients with greatly increased prolactin had normal levels of chemokines, and in vitro, high levels of prolactin decreased T-helper cell activation.
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| 9. |
- Generó, Magalí Martí, 1983-, et al.
(författare)
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A protocol for characterization of extremely preterm infant gut microbiota in double-blind clinical trials
- 2021
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Ingår i: STAR Protocols. - Cambridge, MA, United States : Cell press. - 2666-1667. ; 2:3
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Tidskriftsartikel (refereegranskat)abstract
- 16S rRNA gene sequencing enables microbial community profiling, but recovering fecal DNA from extremely premature infants is challenging. Here, we describe an optimized protocol for fecal DNA isolation, library preparation for 16S rRNA gene sequencing, taxonomy assignation, and statistical analyses. The protocol is complemented with a quantitative PCR for probiotic L. reuteri identification. This protocol describes how to characterize preterm infant gut microbiota and relate it to probiotic supplementation and clinical outcomes. It is customizable for other clinical trials. For complete details on the use and execution of this protocol, please refer to Martí et al. (2021) and Spreckels et al. (2021).
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| 10. |
- Humbert, Marion, et al.
(författare)
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Functional SARS-CoV-2 cross-reactive CD4+ T cells established in early childhood decline with age
- 2023
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 120:12
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Tidskriftsartikel (refereegranskat)abstract
- Pre-existing SARS-CoV-2-reactive T cells have been identified in SARS-CoV-2-unexposed individuals, potentially modulating COVID-19 and vaccination outcomes. Here, we provide evidence that functional cross-reactive memory CD4+ T cell immunity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is established in early childhood, mirroring early seroconversion with seasonal human coronavirus OC43. Humoral and cellular immune responses against OC43 and SARS-CoV-2 were assessed in SARS-CoV-2-unexposed children (paired samples at age two and six) and adults (age 26 to 83). Pre-existing SARS-CoV-2-reactive CD4+ T cell responses targeting spike, nucleocapsid, and membrane were closely linked to the frequency of OC43-specific memory CD4+ T cells in childhood. The functional quality of the cross-reactive memory CD4+ T cell responses targeting SARS-CoV-2 spike, but not nucleocapsid, paralleled OC43-specific T cell responses. OC43-specific antibodies were prevalent already at age two. However, they did not increase further with age, contrasting with the antibody magnitudes against HKU1 (β-coronavirus), 229E and NL63 (α-coronaviruses), rhinovirus, Epstein–Barr virus (EBV), and influenza virus, which increased after age two. The quality of the memory CD4+ T cell responses peaked at age six and subsequently declined with age, with diminished expression of interferon (IFN)-γ, interleukin (IL)-2, tumor necrosis factor (TNF), and CD38 in late adulthood. Age-dependent qualitative differences in the pre-existing SARS-CoV-2-reactive T cell responses may reflect the ability of the host to control coronavirus infections and respond to vaccination. Copyright © 2023 the Author(s).
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| 11. |
- Huoman, Johanna, et al.
(författare)
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Combined prenatal Lactobacillus reuteri and omega-3 supplementation synergistically modulates DNA methylation in neonatal T helper cells
- 2021
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Ingår i: Clinical Epigenetics. - : BMC. - 1868-7083 .- 1868-7075. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundEnvironmental exposures may alter DNA methylation patterns of T helper cells. As T helper cells are instrumental for allergy development, changes in methylation patterns may constitute a mechanism of action for allergy preventive interventions. While epigenetic effects of separate perinatal probiotic or omega -3 fatty acid supplementation have been studied previously, the combined treatment has not been assessed. We aimed to investigate epigenome-wide DNA methylation patterns from a sub-group of children in an on-going randomised double-blind placebo-controlled allergy prevention trial using pre- and postnatal combined Lactobacillus reuteri and omega -3 fatty acid treatment. To this end,>866000 CpG sites (MethylationEPIC 850K array) in cord blood CD4+ T cells were examined in samples from all four study arms (double-treatment: n=18, single treatments: probiotics n=16, omega -3 n=15, and double placebo: n=14). Statistical and bioinformatic analyses identified treatment-associated differentially methylated CpGs and genes, which were used to identify putatively treatment-induced network modules. Pathway analyses inferred biological relevance, and comparisons were made to an independent allergy data set.ResultsComparing the active treatments to the double placebo group, most differentially methylated CpGs and genes were hypermethylated, possibly suggesting induction of transcriptional inhibition. The double-treated group showed the largest number of differentially methylated CpGs, of which many were unique, suggesting synergy between interventions. Clusters within the double-treated network module consisted of immune-related pathways, including T cell receptor signalling, and antigen processing and presentation, with similar pathways revealed for the single-treatment modules. CpGs derived from differential methylation and network module analyses were enriched in an independent allergy data set, particularly in the double-treatment group, proposing treatment-induced DNA methylation changes as relevant for allergy development.ConclusionPrenatal L. reuteri and/or omega -3 fatty acid treatment results in hypermethylation and affects immune- and allergy-related pathways in neonatal T helper cells, with potentially synergistic effects between the interventions and relevance for allergic disease. Further studies need to address these findings on a transcriptional level, and whether the results associate to allergy development in the children. Understanding the role of DNA methylation in regulating effects of perinatal probiotic and omega -3 interventions may provide essential knowledge in the development of efficacious allergy preventive strategies.Trial registration ClinicalTrials.gov, ClinicalTrials.gov-ID: NCT01542970. Registered 27th of February 2012-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT01542970.
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| 12. |
- Huoman, Johanna, 1987-
(författare)
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Immune maturation and modulation in childhood allergies : Aspects of epigenetic, mucosal and systemic immune mediators in allergy development and prevention
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The prevalence of allergic diseases has in the past century increased among children in affluent societies. Underlying causes are incompletely disentangled, but decreased diversity in environmental and microbial exposures could drive allergy development. Allergic individuals possess imbalanced immune responses, skewed in favour of Th2 cells along with lesser Th1 and Treg responses. As allergy development early in life increases the risk of developing further allergic manifestations later, early prevention is key. Thus, interventions in pregnancy, early life and childhood may modulate immunity towards tolerance, although underpinnings of immune maturation and modulation in allergy prevention throughout childhood are not entirely understood. In this thesis, these questions are addressed in children with a high propensity of developing allergic disease or who already have manifested allergies.Chemokines are crucial for immune cell recruitment to the allergic reaction site, and associate with allergy development in childhood. In Paper I, circulating levels of the allergy-related chemokines CCL17, CCL18, CCL22, CXCL10 and CXCL11 were studied in the natural course of allergic disease. Elevated levels of the Th2/Treg-regulated chemokine CCL18 in infancy and childhood associated with development of asthma and/or sensitisation. Moreover, this finding conferred higher odds of developing asthma and sensitisation from early school age until adolescence. Additionally, increased levels of the Th1-associated chemokines CXCL10 after birth, and decreased levels of CXCL11 at birth, preceded asthma development later in life. Hence, Paper I showed that circulating chemokine levels in different ways precede allergy development.Epigenetic modifications, such as DNA methylation, comprise a link between the genetic setup and environmental exposures, and regulate processes such as Th cell differentiation. Perinatal treatment with Lactobacillus reuteri and ω-3 fatty acids prevent development of some IgE-mediated manifestations. However, the drivers of the immunostimulating and pro-resolving effects of these treatments are sparsely examined. In Papers II and III, epigenome-wide DNA methylation patterns in CD4+ cells upon pre-and postnatal L. reuteri supplementation alone or in combination with ω-3 fatty acids were studied. In Paper II, the greatest epigenome wide differential methylation was evident at birth, mainly directed towards hypomethylation, indicating transcriptional availability of affected genes. Network analyses revealed several immune related pathways, and a relationship of differentially methylated genes to allergy development. Thus, prenatal L. reuteri treatment seemingly poises Th cells towards immune activation at birth, possibly influencing immune maturation as well as allergy development in the child.In Paper III, epigenome-wide DNA methylation patterns were surveyed at birth. In this on-going trial, mothers are treated during the latter half of pregnancy with a combination of L. reuteri and ω-3 fatty acids. Four different treatment groups were studied, and the largest differential methylation was seen in the double active treatment group. In contrast to Paper II, most CpGs and genes were hypermethylated, indicating repressed gene transcription. In line with Paper II, network analyses showed that T cell and immune mediated pathways were affected by treatment, and synergistic effects of the double treatment were indicated. Taken together, prenatal treatment with L. reuteri and/or ω-3 fatty acids altered the epigenome to different extents at birth, mainly towards hypermethylation, and often affected immune related pathways.Immunomodulatory effects of sublingual immunotherapy in children and adolescents are scarcely investigated. In Paper IV, circulating and salivary immune mediators were investigated in timothy grass-pollen allergic children treated with sublingual immunotherapy. Actively treated children had elevated levels of timothy grass pollen-specific IgA antibodies in saliva, along with increased circulating levels of the Th1-associated chemokines CXCL10 and CXCL11, both after treatment ending and two years later. Taken together, sublingual immunotherapy modulates local and peripheral immune responses in children with timothy grass pollen-induced allergy, by augmenting Th1-responses, lessening Th2-responses and inducing immunomodulatory responses, suggesting induction of tolerance, also partly in the long-term.Altogether, the studies in this thesis have shown altered immune regulation in children developing allergies. Moreover, immunomodulatory effects of prenatal treatment with probiotics and ω-3 fatty acids, and sublingual immunotherapy in children with grass pollen-induced allergic disease, were revealed. DNA methylation patterns and immunologic mediators in blood and saliva could potentially serve as appropriate biomarkers for allergic disease. Long term health benefits can be reached by intervening early in life, and further knowledge about the mechanisms behind this could promote the prevention of allergic diseases and hence improve the quality of life for children and adolescents.
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| 13. |
- Lindau, Robert, 1989-
(författare)
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Immune regulation at the foetal-maternal interface; implications for healthy and complicated pregnancies
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- For a successful pregnancy, the maternal immune system must acquire tolerance towards the paternal antigens present in the semi-allogeneic foetus. This tolerance is mainly established locally at the foetal-maternal interface, where foetally-derived trophoblasts invade the maternal endometrium (called decidua during pregnancy) and come in close proximity to maternal immune cells. The decidua is populated by maternal immune cells of a unique composition, characterised by their suppressive phenotypes that are essential for maintaining tissue homeostasis. Accordingly, failure of immune tolerance can lead to pregnancy complications. Macrophages and regulatory T-cells are enriched in the decidua and are believed to play important roles in the establishment of tolerance. However, there is limited information regarding the factors that regulate their functions and if their function is compromised in pregnancy complications.The aim of this thesis was to further elucidate which factors are responsible for induction of the regulatory phenotypes of macrophages and T-cells found in the decidua, how tissue resident cells in the decidua contribute to this and if this system is compromised during pregnancy complications, such as preeclampsia and recurrent pregnancy loss.Decidual stromal cells (DSCs) constitute the largest population of tissue resident cells in the decidua. In an in vitro system of macrophage differentiation, we found that Isolated peripheral blood monocytes cultured in conditioned medium (CM) from DSCs acquired a high expression of the regulatory M2 markers CD163, CD209 and CD14, and a low expression of CD86, characteristics of decidual macrophages. This induction was in part mediated by macrophage-colony stimulating factor (M-CSF), as neutralising its effects reduced the expression of CD163. However, since only a partial reduction was reached, other factors are involved. Another likely candidate for this polarisation is interleukin (IL)-34, a second ligand for the M-CSF receptor. We showed that IL-34 is expressed by both DSCs and the foetal placenta. Further, in vitro, IL-34 was able to induce macrophages with similar properties as that of M-CSF-induced macrophages, with high expression of CD163, CD209 and CD14. This was also coupled to a cytokine secretion profile similar to M-CSF-induced macrophages, with high production of IL-10, low production of tumour necrosis factor (TNF) and no production of IL-12. We found no evidence of IL-34 being aberrantly expressed in placentas from preeclamptic women.In addition to promoting induction of macrophages with a regulatory phenotype, CM from DSCs promoted expansion of Foxp3+CD25bright regulatory T (Treg) cells in an in vitro polarisation system, in a SMAD3 dependent manner. Protein profiling of DSCs revealed limited production of the Th2 related IL-13, IL-4, IL-33 and thymic stromal lymphopoietin (TSLP), as well as no production of the Th17 related IL-17A and chemokine (C-C motif) ligand (CCL) 20. Instead we found that DSCs were more prone to production of regulatory factors, such as M-CSF, leukaemia inhibitory factor (LIF) and transforming growth factor (TGF)-β, albeit with addition of the more pro-inflammatory IL-6, chemokine (C-X-C motif) ligand (CXCL) 8 and the Th1-related CXCL10.We also investigated if the placenta´s ability to induce Treg cells and regulatory M2 macrophages is compromised in women with a history of unexplained recurrent pregnancy loss (uRPL) and if the placental secreted protein profile is skewed to a pro-inflammatory response in uRPL. Using surplus materials from chorionic villous sampling (CVS), we generated CM from placental tissue taken from healthy and uRPL pregnancies and used this to polarise macrophages and T-cells in vitro. We found no difference in the ability to induce Treg cells and regulatory M2 macrophages between the healthy group and the uRPL group. Likewise, no differences in the protein profile was observed between the two groups.Taken together, our findings imply that DSCs produce a variety of factors promoting foetal tolerance by induction of Treg cells and regulatory M2 macrophages. Furthermore, we also showed that the placenta retained its ability to induce Treg cells and regulatory M2 macrophages in women with a history of uRPL.
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| 14. |
- Lizano Fallas, Verónica, 1985-
(författare)
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Toxicoproteomics, from finding molecular targets to evaluating the impact on human health
- 2023
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The exposome refers to all exposures, including exposures to chemicals, that an individual may encounter over the whole life, from conception to death, that influence the individual’s health. To date, over 200,000 chemicals have been registered under the legislative framework of the European Union. Exposomics studies have revealed that individuals are exposed to chemical mixtures consisting of hundreds of compounds simultaneously. The risks to human health posed by many of these chemicals and chemical mixtures are still unknown and require evaluation. Traditional methods for assessing chemicals and chemical mixtures have been inadequate in addressing the increasing number of potentially toxic compounds in the environment. Current high-throughput toxicology methods, which involve the application of batteries of in vitro bioassays, can reduce the time and costs of analysis. However, these methods evaluate the impact on well-established pathways that have already been identified as being affected by exposure, making it difficult to discover new modes of action. The goal of this thesis is to provide a method to unravel the targets of chemicals for a better understanding of the mechanisms of action of chemicals and chemical mixtures under the scenario of the exposome. The proteome integral solubility alteration (PISA) assay is a proteome-wide approach for drug-target identification. However, implementing the PISA assay to address toxicological challenges requires different experimental considerations from chemical properties and toxicology principles. Moreover, it is necessary to translate the data from target identification to an understanding of the potential impact on human health. Therefore, three steps were followed to implement the PISA method in the field of toxicology: i) experimental considerations of the method for toxicology and chemical assessment purposes, ii) analysis of the method capability in the field of toxicology, and iii) development of pipelines from the target identification to the understanding of potential impact on human health. The results showed the capability of the PISA assay to identify the protein targets of single chemicals and chemical mixtures, extending, in an unbiased manner, the list of evaluated biological pathways in current available methodologies. The approach presented here reduces the time and cost associated with experimental and data analysis work, which could aid in the chemical risk assessment process in the context of the exposome.
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| 15. |
- Qazi, Khaleda Rahman, et al.
(författare)
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Extremely Preterm Infants Have Significant Alterations in Their Conventional T Cell Compartment during the First Weeks of Life
- 2020
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Ingår i: Journal of Immunology. - : AMER ASSOC IMMUNOLOGISTS. - 0022-1767 .- 1550-6606. ; 204:1, s. 68-77
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Tidskriftsartikel (refereegranskat)abstract
- Extremely preterm neonates are particularly susceptible to infections, likely because of severely impaired immune function. However, little is known on the composition of the T cell compartment in early life in this vulnerable population. We conducted a comprehensive phenotypic flow cytometry-based longitudinal analysis of the peripheral conventional T cell compartment of human extremely low gestational age neonates (ELGAN) with extremely low birth weight (ELBW; amp;lt;1000 g) participating in a randomized placebo-controlled study of probiotic supplementation. PBMCs from ELGAN/ELBW neonates were collected at day 14, day 28, and postmenstrual week 36. Comparisons were made with full-term 14-d-old neonates. Total CD4(+) and CD8(+) T cell frequencies were markedly lower in the preterm neonates. The reduction was more pronounced among the CD8(+) population, resulting in an increased CD4/CD8 ratio. The preterm infants were also more Th2 skewed than the full-term infants. Although the frequency of regulatory T cells seemed normal in the ELGAN/ELBW preterm neonates, their expression of the homing receptors alpha 4 beta 7, CCR4, and CCR9 was altered. Notably, ELGAN/ELBW infants developing necrotizing enterocolitis before day 14 had higher expression of CCR9 in CD4(+)T cells at day 14. Chorioamnionitis clearly associated with reduced T regulatory cell frequencies and functional characteristics within the preterm group. Finally, probiotic supplementation with Lactobacillus reuteri did not impose any phenotypic changes of the conventional T cell compartment. In conclusion, notable immaturities of the T cell compartment in ELGAN/ELBW neonates may at least partially explain their increased susceptibility to severe immune-mediated morbidities.
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| 16. |
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| 17. |
- van der Heiden, Marieke, et al.
(författare)
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Characterization of the gamma delta T-cell compartment during infancy reveals clear differences between the early neonatal period and 2 years of age
- 2020
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Ingår i: Immunology and Cell Biology. - : Wiley. - 0818-9641 .- 1440-1711. ; 98:1, s. 79-87
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Tidskriftsartikel (refereegranskat)abstract
- gamma delta T cells are unconventional T cells that function on the border of innate and adaptive immunity. They are suggested to play important roles in neonatal and infant immunity, although their phenotype and function are not fully characterized in early childhood. We aimed to investigate gamma delta T cells in relation to age, prematurity and cytomegalovirus (CMV) infection. Therefore, we used flow cytometry to characterize the gamma delta T-cell compartment in cord blood and peripheral blood cells from 14-day-, 2-year- and 5-year-old children, as well as in peripheral blood samples collected at several time points during the first months of life from extremely premature neonates. gamma delta T cells were phenotypically similar at 2 and 5 years of age, whereas cord blood was divergent and showed close proximity to gamma delta T cells from 14-day-old neonates. Interestingly, 2-year-old children and adults showed comparable V delta 2(+) gamma delta T-cell functionality toward both microbial and polyclonal stimulations. Importantly, extreme preterm birth compromised the frequencies of V delta 1(+) cells and affected the functionality of V delta 2(+) gamma delta T cells shortly after birth. In addition, CMV infection was associated with terminal differentiation of the V delta 1(+) compartment at 2 years of age. Our results show an adult-like functionality of the gamma delta T-cell compartment already at 2 years of age. In addition, we demonstrate an altered gamma delta T-cell phenotype early after birth in extremely premature neonates, something which could possible contribute to the enhanced risk for infections in this vulnerable group of children.
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| 18. |
- Åkesson, Julia, et al.
(författare)
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Proteomics reveal biomarkers for diagnosis, disease activity and long-term disability outcomes in multiple sclerosis
- 2023
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 14:1
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Tidskriftsartikel (refereegranskat)abstract
- Sensitive and reliable protein biomarkers are needed to predict disease trajectory and personalize treatment strategies for multiple sclerosis (MS). Here, we use the highly sensitive proximity-extension assay combined with next-generation sequencing (Olink Explore) to quantify 1463 proteins in cerebrospinal fluid (CSF) and plasma from 143 people with early-stage MS and 43 healthy controls. With longitudinally followed discovery and replication cohorts, we identify CSF proteins that consistently predicted both short- and long-term disease progression. Lower levels of neurofilament light chain (NfL) in CSF is superior in predicting the absence of disease activity two years after sampling (replication AUC = 0.77) compared to all other tested proteins. Importantly, we also identify a combination of 11 CSF proteins (CXCL13, LTA, FCN2, ICAM3, LY9, SLAMF7, TYMP, CHI3L1, FYB1, TNFRSF1B and NfL) that predict the severity of disability worsening according to the normalized age-related MS severity score (replication AUC = 0.90). The identification of these proteins may help elucidate pathogenetic processes and might aid decisions on treatment strategies for persons with MS.
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