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Query: "author" (Matija Rijavec) .

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1.
Solid cancer patients achieve adequate immunogenicity and low rate of severe adverse events after SARS-CoV-2 vaccination
Urška Janžič, Urška Bidovec, Katja Mohorčič, Loredana Mrak, Nina Fokter Dovnik, Marija Ivanović, Maja Ravnik, Marina Čakš, Erik Škof, Jerneja Debeljak, Peter Korošec, Matija Rijavec, 2022, original scientific article

Abstract: Background: SARS-CoV-2 vaccination in cancer patients is crucial to prevent severe COVID-19 disease course. Methods: This study assessed immunogenicity of cancer patients on active treatment receiving mRNA-based SARS-CoV-2 vaccine by detection of anti-SARS-CoV-2 S1 IgG antibodies in serum, before, after the first and second doses and 3 months after a complete primary course of vaccination. Results were compared with healthy controls. Results: Of 112 patients, the seroconversion rate was 96%. A significant reduction in antibody levels was observed 3 months after vaccination in patients receiving immune checkpoint inhibitors versus control participants (p < 0.001). Adverse events were mostly mild. Conclusion: Immunogenicity after mRNA-based vaccine in cancer patients is adequate but influenced by the type of anticancer therapy. Antibody levels decline after 3 months, and thus a third vaccination is warranted.
Keywords: onkološko zdravljenje, imunogenost, osnovno cepljenje mRNA, čvrsti tumorji, anticancer treatment, immunogenicity, mRNA-based vaccination, solid cancer
Published in DiRROS: 24.06.2022; Views: 284; Downloads: 102
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2.
SERPING1 variants and C1-INH biological function : a close relationship with C1-INH-HAE
Christian Drouet, Alberto López Lera, Arije Ghannam, Margarita López-Trascasa, Sven Cichon, Denise Ponard, Faidra Parsopoulou, Hana Grombirikova, Tomas Freiberger, Matija Rijavec, Camila Lopes Veronez, João Bosco Pesquero, Anastasios E. Germenis, 2022, review article

Abstract: Hereditary angioedema with C1 Inhibitor deficiency (C1-INH-HAE) is caused by a constellation of variants of the SERPING1 gene (n = 809; 1,494 pedigrees), accounting for 86.8% of HAE families, showing a pronounced mutagenic liability of SERPING1 and pertaining to 5.6% de novo variants. C1-INH is the major control serpin of the kallikrein–kinin system (KKS). In addition, C1-INH controls complement C1 and plasminogen activation, both systems contributing to inflammation. Recognizing the failed control of C1s protease or KKS provides the diagnosis of C1-INH-HAE. SERPING1 variants usually behave in an autosomal-dominant character with an incomplete penetrance and a low prevalence. A great majority of variants (809/893; 90.5%) that were introduced into online database have been considered as pathogenic/likely pathogenic. Haploinsufficiency is a common feature in C1-INH-HAE where a dominant-negative variant product impacts the wild-type allele and renders it inactive. Small (36.2%) and large (8.3%) deletions/duplications are common, with exon 4 as the most affected one. Point substitutions with missense variants (32.2%) are of interest for the serpin structure–function relationship. Canonical splice sites can be affected by variants within introns and exons also (14.3%). For noncanonical sequences, exon skipping has been confirmed by splicing analyses of patients' blood-derived RNAs (n = 25). Exonic variants (n = 6) can affect exon splicing. Rare deep-intron variants (n = 6), putatively acting as pseudo-exon activating mutations, have been characterized as pathogenic. Some variants have been characterized as benign/likely benign/of uncertain significance (n = 74). This category includes some homozygous (n = 10) or compound heterozygous variants (n = 11). They are presenting with minor allele frequency (MAF) below 0.00002 (i.e., lower than C1-INH-HAE frequency), and may be quantitatively unable to cause haploinsufficiency. Rare benign variants could contribute as disease modifiers. Gonadal mosaicism in C1-INH-HAE is rare and must be distinguished from a de novo variant. Situations with paternal or maternal disomy have been recorded (n = 3). Genotypes must be interpreted with biological investigation fitting with C1-INH expression and typing. Any SERPING1 variant reminiscent of the dysfunctional phenotype of serpin with multimerization or latency should be identified as serpinopathy.
Keywords: Hereditary angioedemas -- genetics -- diagnosis, genetic variation, serpins, SERPING1 gene, C1-INH, C1-INH-HAE, C1 inhibitor, serpinopathy
Published in DiRROS: 06.04.2022; Views: 326; Downloads: 211
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3.
Utility of telomerase gene mutation testing in patients with idiopathic pulmonary fibrosis in routine practice
Julij Šelb, Katarina Osolnik, Izidor Kern, Peter Korošec, Matija Rijavec, 2022, original scientific article

Abstract: Recent studies have suggested that causative variants in telomerase complex genes (TCGs) are present in around 10% of individuals with idiopathic pulmonary fibrosis (IPF) regardless of family history of the disease. However, the studies used a case-control rare variant enrichment study design which is not directly translatable to routine practice. To validate the prevalence results and to establish the individual level, routine clinical practice, and utility of those results we performed next generation sequencing of TCGs on a cohort of well-characterized consecutive individuals with IPF (diagnosis established according to ATS/ERS/JRS/ALAT guidelines). Of 27 IPF patients, three had a family history of idiopathic interstitial pneumonia (familial IPF) and 24 did not (sporadic IPF). Pathogenic/likely-pathogenic variants (according to American College of Medical Genetics criteria) in TCG were found in three individuals (11.1%) of the whole cohort; specifically, they were present in 2 out of 24 (8.3%) of the sporadic and in 1 out of 3 (33.3%) of the patients with familial IPF. Our results, which were established on an individual-patient level study design and in routine clinical practice (as opposed to the case-control study design), are roughly in line with the around 10% prevalence of causative TCG variants in patients with IPF.
Keywords: telomerase, idiopathic pulmonary fibrosis, genetic variation, telomerase complex
Published in DiRROS: 07.02.2022; Views: 366; Downloads: 144
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4.
Heterogeneous response of airway eosinophilia to anti-IL-5 biologics in severe asthma patients
Maruša Kopač, Matija Rijavec, Peter Korošec, Urška Bidovec, Izidor Kern, Romana Vantur, Sabina Škrgat, 2022, original scientific article

Abstract: Many questions concerning responders (R) and nonresponders (NR) in severe eosinophilic asthma (SEA) after blocking the IL-5 (interleukin 5) pathway are still not clear, especially regarding the early parameters of response to biologics in personalized treatment strategies. We evaluated 17 SEA patients treated with anti-IL-5 biologics (16 patients mepolizumab, one patient benralizumab) before the introduction of biologics, and at a week 16 follow-up. Clinical, cellular and immunological parameters in peripheral blood were measured in R and NR. Sputum induction with the measurement of cellular and immunological parameters was performed at 16 weeks only. There were 12 R and 5 NR to biologics. After 16 weeks, there was a significant improvement in percentages of FEV1 (p = 0.001), and asthma control test (ACT) (p = 0.001) in the R group, but not in NR. After 16 weeks, the eosinophils in induced sputum were 27.0% in NR and 4.5% in R (p = 0.05), with no difference in IL-5 concentrations (p = 0.743). Peripheral eosinophilia decreased significantly in NR (p = 0.032) and R (p = 0.002). In patients with SEA on anti-IL-5 therapy, there was a marked difference in airway eosinophilic inflammation between R and NR already at 16 weeks, after anti-IL-5 introduction.
Published in DiRROS: 13.01.2022; Views: 471; Downloads: 255
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5.
Treatment outcome clustering patterns correspond to discrete asthma phenotypes in children
Ivana Banić, Mario Lovrić, Gerald Cuder, Roman Kern, Matija Rijavec, Peter Korošec, Mirjana Kljajić-Turkalj, 2021, original scientific article

Abstract: Despite widely and regularly used therapy asthma in children is not fully controlled. Recognizing the complexity of asthma phenotypes and endotypes imposed the concept of precision medicine in asthma treatment. By applying machine learning algorithms assessed with respect to their accuracy in predicting treatment outcome, we have successfully identified 4 distinct clusters in a pediatric asthma cohort with specific treatment outcome patterns according to changes in lung function (FEV1 and MEF50), airway inflammation (FENO) and disease control likely affected by discrete phenotypes at initial disease presentation, differing in the type and level of inflammation, age of onset, comorbidities, certain genetic and other physiologic traits. The smallest and the largest of the 4 clusters- 1 (N = 58) and 3 (N = 138) had better treatment outcomes compared to clusters 2 and 4 and were characterized by more prominent atopic markers and a predominant allelic (A allele) effect for rs37973 in the GLCCI1 gene previously associated with positive treatment outcomes in asthmatics. These patients also had a relatively later onset of disease (6 + yrs). Clusters 2 (N = 87) and 4 (N = 64) had poorer treatment success, but varied in the type of inflammation (predominantly neutrophilic for cluster 4 and likely mixed-type for cluster 2), comorbidities (obesity for cluster 2), level of systemic inflammation (highest hsCRP for cluster 2) and platelet count (lowest for cluster 4). The results of this study emphasize the issues in asthma management due to the overgeneralized approach to the disease, not taking into account specific disease phenotypes.
Keywords: asthma, allergy and immunology, pediatrics, machine learning, treatment outcome, phenotypes, childhood asthma, clustering
Published in DiRROS: 16.08.2021; Views: 561; Downloads: 338
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6.
Hymenoptera venom immunotherapy : immune mechanisms of induced protection and tolerance
Ajda Demšar, Peter Korošec, Mitja Košnik, Mihaela Zidarn, Matija Rijavec, 2021, review article

Abstract: Hymenoptera venom allergy is one of the most severe allergic diseases, with a considerable prevalence of anaphylactic reaction, making it potentially lethal. In this review, we provide an overview of the current knowledge and recent findings in understanding induced immune mechanisms during different phases of venom immunotherapy. We focus on protection mechanisms that occur early, during the build-up phase, and on the immune tolerance, which occurs later, during and after Hymenoptera venom immunotherapy. The short-term protection seems to be established by the early desensitization of mast cells and basophils, which plays a crucial role in preventing anaphylaxis during the build-up phase of treatment. The early generation of blocking IgG antibodies seems to be one of the main reasons for the lower activation of effector cells. Long-term tolerance is reached after at least three years of venom immunotherapy. A decrease in basophil responsiveness correlates with tolerated sting challenge. Furthermore, the persistent decline in IgE levels and, by monitoring the cytokine profiles, a shift from a Th2 to Th1 immune response, can be observed. In addition, the generation of regulatory T and B cells has proven to be essential for inducing allergen tolerance. Most studies on the mechanisms and effectiveness data have been obtained during venom immunotherapy (VIT). Despite the high success rate of VIT, allergen tolerance may not persist for a prolonged time. There is not much known about immune mechanisms that assure longterm tolerance post-therapy.
Keywords: allergy and immunology, hypersensitivity, immunotherapy, immune tolerance, venoms, Hymenoptera, Hymenoptera venom, short-term protection, long-term tolerance
Published in DiRROS: 16.08.2021; Views: 450; Downloads: 146
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7.
Gene expression levels of the prolyl hydroxylase domain proteins PHD1 and PHD2 but not PHD3 are decreased in primary tumours and correlate with poor prognosis of patients with surgically resected non-small-cell lung cancer
Ana Koren, Matija Rijavec, Tomaž Krumpestar, Izidor Kern, Aleksander Sadikov, Tanja Čufer, Peter Korošec, 2021, original scientific article

Abstract: Background: Hypoxia correlates with poor prognosis in several cancer types, including lung cancer. Prolyl hydroxylase domain proteins (PHDs) play a role in cell oxygen sensing, negatively regulating the hypoxia-inducible factor (HIF) pathway. Our study aim was to evaluate PHD1, PHD2 and PHD3 mRNA expression levels in primary tumours and normal lungs of non-small-cell lung cancer (NSCLC) patients and to correlate it with selected regulators of HIF signalling, with clinicopathological characteristics and overall survival (OS). Methods: Tumour tissue samples were obtained from 60 patients with surgically resected NSCLC who were treated with radical surgery. In 22 out of 60 cases, matching morphologically normal lung tissue was obtained. PHD1, PHD2 and PHD3 mRNA expressions were measured using RT-qPCR. Results: The PHD1 and PHD2 mRNA levels in primary tumours were significantly decreased compared to those in normal lungs (both p < 0.0001). PHD1 and PHD2 expression in tumours was positively correlated (rs = 0.82; p < 0.0001) and correlated well with HIF pathway downstream genes HIF1A, PKM2 and PDK1. Decreased PHD1 and PHD2 were associated with larger tumour size, higher tumour stage (PHD1 only) and squamous cell carcinoma. Patients with low PHD1 and patients with low PHD2 expression had shorter OS than patients with high PHD1 (p = 0.02) and PHD2 expression (p = 0.01). PHD1 showed borderline independent prognostic values in multivariate analysis (p = 0.06). In contrast, we found no associations between PHD3 expression and any of the observed parameters. Conclusions: Our results show that reduced expression of PHD1 and PHD2 is associated with the development and progression of NSCLC. PHD1 could be further assessed as a prognostic marker in NSCLC.
Keywords: non-small-cell lung carcinoma, prognosis, non-small cell lung cancer, mRNA expression, prolyl hydroxylase domain proteins
Published in DiRROS: 21.05.2021; Views: 800; Downloads: 549
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8.
T2-high asthma, classified by sputum mRNA expression of IL4, IL5, and IL13, is characterized by eosinophilia and severe phenotype
Matija Rijavec, Tomaž Krumpestar, Sabina Škrgat, Izidor Kern, Peter Korošec, 2021, original scientific article

Abstract: Asthma is a common chronic disease, with different underlying inflammatory mechanisms. Identification of asthma endotypes, which reflect a variable response to different treatments, is important for more precise asthma management. T2 asthma is characterized by airway inflammation driven by T2 cytokines including interleukins IL-4, IL-5, and IL-13. This study aimed to determine whether induced sputum samples can be used for gene expression profiling of T2-high asthma classified by IL4, IL5, and IL13 expression. Induced sputum samples were obtained from 44 subjects, among them 36 asthmatic patients and eight controls, and mRNA expression levels of IL4, IL5, and IL13 were quantified by RT-qPCR. Overall, gene expression levels of IL4, IL5, and IL13 were significantly increased in asthmatic patients' samples compared to controls and there was a high positive correlation between expressions of all three genes. T2 gene mean was calculated by combining the expression levels of all three genes (IL4, IL5, and IL13) and according to T2 gene mean expression in controls, we set a T2-high/T2-low cutoff value. Twenty-four (67%) asthmatic patients had T2-high endotype and those patients had significantly higher eosinophil blood and sputum counts. Furthermore, T2-high endotype was characterized as a more severe, difficult-to-treat asthma, and often uncontrolled despite the use of inhaled and/or oral corticosteroids. Therefore, the majority of those patients (15 [63%] of 24) needed adjunct biological therapy to control their asthma symptoms/exacerbations. In conclusion, we found that interleukins IL4, IL5, and IL13 transcripts could be effectively detected in sputum from asthmatic patients. Implementation of T2 gene mean can be used as sputum molecular biomarker to categorize patients into T2-high endotype, characterized by eosinophilia and severe, difficult-to-treat asthma, and often with a need for biological treatment.
Keywords: asthma, gene expression, interleukin-4, interleukin-5, interleukin-13, severe asthma, endotype, IL-4, IL-5, IL-13, biologic treatment
Published in DiRROS: 02.02.2021; Views: 848; Downloads: 455
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9.
Chemokines during anaphylaxis : the importance of CCL2 and CCL2-dependent chemotactic activity for basophils
Romana Vantur, Maruša Rihar, Ana Koren, Matija Rijavec, Peter Kopač, Urška Bidovec, Renato Eržen, Peter Korošec, 2020, original scientific article

Abstract: Background: The role of chemokines in anaphylaxis is unclear. Methods: We prospectively recruited 49 patients presenting to the emergency department with an acute episode of anaphylaxis and 28 healthy subjects. We measured serum levels of the chemokines CCL2, CCL5, CCL7, CCL8, CCL11, CCL13, CCL17, CCL21, CCL22, CCL24, and CCL26, tryptase, the absolute number of circulating basophils, monocytes, lymphocytes, and PMNs, and whole blood FCER1A, CPA3 and HDC gene expression at two time points: during the anaphylactic episode and in convalescent samples collected approximately 3 months later. We then investigated the in vitro chemotactic activity of chemokines induced during anaphylaxis for the in vitro migration of the corresponding cells. Results: Only CCL2 chemokine levels were signifcantly increased in anaphylaxis samples (median 514 pg/ml) compared to convalescent samples (284 pg/ml, P<0.0001) and healthy subjects (279 pg/ml, P<0.0001); there was no signifcant diference in any of the other chemokines. There was a signifcant positive correlation between the rates of increase of serum CCL2 (median [range]: 106.0% [-44.7% to 557.4%]) and tryptase (133.8% [-6.6% to 893.4%]; r=0.68, P<0.0001) and between the acute concentration of serum CCL2 and the acute concentration of serum tryptase (r=0.77, P<0.0001). The number of circulating basophils, but not other blood cells, signifcantly decreased during anaphylaxis (median 5.0 vs. 19.1 cells/[micro]l in convalescent samples; P<0.0001); a decrease in whole-blood gene expression of basophil markers (PKeywords: anaphylaxis, chemokines, tryptases, basophils, chemotaxis, CCL2, cell migration
Published in DiRROS: 18.01.2021; Views: 916; Downloads: 372
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10.
GLCCI1 polymorphism rs37973 and asthma treatment response to inhaled corticosteroids
Matija Rijavec, Mateja Žavbi, Anton Lopert, Matjaž Fležar, Peter Korošec, 2018, original scientific article

Abstract: Background. Asthma treatment response is highly variable and pharmacogenetic markers that predict treatment response would be one step closer to personalized treatment. GWAS studies have shown that polymorphisms GLCCI1 could be associated with asthma treatment response to inhaled corticosteroids (ICS). Materials and methods. We genotyped rs37973 of GLCCI1 in 208 adult asthma patients treated with ICS. Change in % predicted FEV1 was analysed after short-term (3 months) and after long-term (at least 3 years) treatment. Treatment success was defined as good when FEV1 decreased less than 30 ml/year. Results. After 3 months of treatment, change of % predicted FEV1 was higher in patients with GG genotype than in patients with AG+AA genotype, and this genotype dependent difference was only evident in non-smokers. Similar results were found after at least 3 years of treatment when all patients were analysed, in non-smokers and patients with atopy. Even though, no differences in treatment success (good vs. poor response) were observed when analysing the entire group of patients, genotype dependent treatment success was highly influenced by smoking and atopy. GG genotype was overrepresented in non-smokers and patients with atopy with good response. Conclusions. Rs37973 was associated with short- and long-term treatment response; however, there was a great influence of smoking and atopy on pharmacogenetic association. Furthermore, we found GG genotype to be associated with better treatment response, what is contrary to results found in GWAS.
Keywords: asthma -- diagnosis -- therapy, pharmacogenetics, genetic polymorphism, smoking, inhaled corticosteroids, atopy, GLCCI1, FEV1, rs37973
Published in DiRROS: 16.12.2020; Views: 878; Downloads: 224
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