Malgorzata Pawelczyk

MicroRNAs and the immune response to respiratory virus infections

MicroRNAs (miRNAs) are small ssRNA molecules, which are involved in gene expression regulation at the post-transcriptional level. Their biological functions include modulation of both innate and adaptive immune response. miRNAs participate in the maintenance of the airway epithelial barrier and are also implicated in the modulation of antiviral defense in epithelial cells. The immune response to respiratory viruses such as rhinovirus, influenza virus and respiratory syncytial virus is associated with an altered expression of distinct miRNAs, and the changes in the miRNA expression profile in epithelial cells may contribute to the pathogenesis of both acute and chronic airway disease. Understanding the role of these small molecules in the antiviral immune response and identification of miRNAs target genes may help to clarify the mechanisms of virus-host interaction, and in the future may lead to development of new antiviral treatments.

The influence of statin therapy on platelet activity markers in hyperlipidemic patients after ischemic stroke.

Introduction Low-density lipoprotein cholesterol (LDL-C) has been reported to increase platelet activation. Reducing the level of LDL-C with statins induces important pleiotropic effects such as platelet inhibition. This association between platelet activity and statin therapy may be clinically important in reducing the risk of ischemic stroke. We investigated the effect of simvastatin therapy on platelet activation markers (platelet CD62P, sP-selectin, and platelet-derived microparticles (PDMPs)) in hyperlipidemic patients after ischemic stroke. Material and methods The study group consisted of 21 hyperlipidemic patients after ischemic stroke confirmed by CT, and 20 healthy subjects served as controls. We assessed the CD62P expression on resting and thrombin-activated blood platelets. CD62P and PDMPs were analyzed by the use of monoclonal antibodies anti-CD61 and anti-CD62 on a flow cytometer. The level of sP-selectin in serum was measured by the ELISA (enzyme-linked immunosorbent assay) method. All markers were re-analyzed after 6 months of treatment with simvastatin (20 mg/day). Results Hyperlipidemic patients presented a significantly higher percentage of CD62+ platelets and higher reactivity to thrombin compared to control subjects. After simvastatin therapy hyperlipidemic patients showed a reduction of the percentage of resting CD62P(+) platelets (p = 0.005) and a reduction of expression and percentage of CD62P(+) platelets after activation by thrombin (median p < 0.05; percentage: p = 0.001). A decrease of sP-selectin levels (p = 0.001) and percentage of PDMPs (p < 0.05) in this group was also observed. Conclusions HMG-CoA reductase inhibitor therapy in stroke patients with hyperlipidemia may be useful not only due to the lipid-lowering effect but also because of a significant role in reduction of platelet activation and reactivity.

The Influence of Hyperlipidemia on Platelet Activity Markers in Patients after Ischemic Stroke

Background: To investigate the relationship between hyperlipidemia and platelet activation markers – platelet and soluble P-selectin (sP-selectin), and platelet-derived microparticles (PDMPs) – in patients after ischemic stroke. Methods: 41 patients after ischemic stroke (>3 months) confirmed by CT were divided into 2 groups: with hyperlipidemia (HL, n = 21) and normolipidemia (NL, n = 20). Twenty healthy subjects served as controls. CD62P-positive platelets and PDMPs in whole blood were analyzed by the use of a flow cytometer and anti-CD61 and anti-CD62P monoclonal antibodies. Platelets were activated by thrombin (0.08 units). The level of sP-selectin in serum was measured by ELISA. Results: We observed a significantly higher CD62P expression and percentage of CD62P-positive resting and thrombin-activated platelets in the HL as compared to the NL group. The sP-selectin concentration was also significantly higher in HL than NL subjects (p < 0.05). Moreover, we observed a significantly higher percentage of PDMPs in patients after stroke (NL: p < 0.05; HL: p = 0.005) in comparison with the control group. Conclusions: Patients after stroke present symptoms of platelet hyperreactivity. HL in the patients may be a risk factor for vascular events due to the increase in platelet activation.

The Role of Human Parainfluenza Virus Infections in the Immunopathology of the Respiratory Tract

Viral infections are leading causes of both upper and lower airway acute illness in all age groups of healthy persons, and have also been implicated in the acute exacerbations of chronic respiratory disorders like asthma and COPD. Human rhinovirus, respiratory syncytial virus, influenza virus and coronavirus have been considered as the most important respiratory pathogens and relatively little attention has been paid to the role of parainfluenza viruses (hPIVs). Human parainfluenza viruses are single-stranded RNA viruses belonging to the paramyxovirus family that may evoke lower respiratory infections in infants, children and immunocompromised individuals. Among non-immune compromised adults, hPIV infection typically causes mild disease manifested as upper respiratory tract symptoms and is infrequently associated with severe croup or pneumonia. Moreover, hPIV infection may be associated with viral exacerbations of chronic airway diseases, asthma or COPD or chronic rhinosinusitis. In this review, we summarized the basic epidemiology and immunology of hPIVs and addressed the more recent data implicating the role of parainfluenza viruses in the exacerbation of chronic airway disorders.

The impact of hyperglycemia and hyperlipidemia on plasma P-selectin and platelet markers after ischemic stroke

Introduction Platelet activation plays a key role in the pathogenesis of ischemic cerebrovascular diseases. Thus, it is very important to identify novel pharmacological targets for platelet inhibition to improve ischemic stroke treatment. The aim of the study was to assess the relationship between metabolic disorders and platelet activity markers in patients with acute ischemic stroke. Material and methods Ninety-four patients with acute ischemic stroke were divided into four groups with: normolipidemia and normoglycemia (NL/NG), n = 25; normolipidemia and hyperglycemia (NL/HG), n = 21; hyperlipidemia and normoglycemia (HL/NG), n = 27; hyperlipidemia and hyperglycemia (NL/NG), n = 21. Twenty-one healthy subjects served as controls. We assessed the CD62P expression on resting and thrombin-activated blood platelets using the flow cytometer and anti-CD61 and anti-CD62P monoclonal antibodies. CD61-positive microparticles were defined as platelet-derived microparticles. The level of sP-selectin in serum was measured by the ELISA method. Results We observed a significant influence of hyperlipidemia and hyperglycemia on sP-selectin concentration. A strong correlation between higher sP-selectin concentration and enhanced LDL (p = 0.001), total cholesterol (p = 0.02), HbA1c level (p < 0.001) was noticed. The level of sP-selectin and PDMPs (p < 0.001) were significantly higher in all groups of stroke patients compared with the controls. CD62P expression on resting and thrombin activated platelets were significantly lower in groups of patients with stroke. Conclusions Hyperlipidemia and hyperglycemia exert an equal stimulatory effect on tested platelet markers but with no synergistic action in stroke patients with both of the metabolic comorbidities. sP-selectin concentration in stroke patients best reflects the impact of hyperglycemia and hyperlipidemia on vascular lesions and platelet activation.

Periostin in Exhaled Breath Condensate and in Serum of Asthmatic Patients: Relationship to Upper and Lower Airway Disease

Purpose Periostin is considered a biomarker for eosinophilic airway inflammation and have been associated with NSAID-Exacerbated Respiratory Disease (NERD) and chronic rhinosinusitis (CRS). In this study, we aimed to evaluate periostin in exhaled breath condensate (EBC) and in serum of patients with various asthma phenotypes. Methods The study included 40 asthmatic patients (22 with NERD) and 17 healthy controls. All the procedures (questionnaire, spirometry, FeNO, nasal swabs, EBC collecting, and blood sampling) were performed on the same day. Periostin concentrations were measured using an ELISA kit. Results Periostin was detected in EBC from 37 of 40 asthmatics and in 16 from 17 of controls. The concentration of periostin in EBC did not differ between the study groups and was not associated with NERD or asthma severity. However, the EBC periostin was significantly higher in asthmatics with CRS as compared to those without (3.1 vs 2 ng/mL, P=0.046). Patients with positive bacterial culture from nasal swabs had higher EBC periostin concentrations than those without (3.2 vs 2.1 ng/mL; P=0.046). The mean serum periostin level was higher in asthmatics with a 1-year history of exacerbation than in those without (3.2 vs 2.3 ng/mL, P=0.045). Asthmatics with skin manifestation of NSAIDs hypersensitivity had higher serum periostin levels as compared to those without (3.5 vs 2.3 ng/mL; P=0.03). Conclusions EBC periostin levels seem to reflect intensity of upper airway disease in asthmatics, while serum levels of periostin are associated with asthma activity (exacerbations or FeNO) or NERD subphenotypes.

Innate Immune Response to Viral Infections in Primary Bronchial Epithelial Cells is Modified by the Atopic Status of Asthmatic Patients

Purpose In order to gain an insight into determinants of reported variability in immune responses to respiratory viruses in human bronchial epithelial cells (HBECs) from asthmatics, the responses of HBEC to viral infections were evaluated in HBECs from phenotypically heterogeneous groups of asthmatics and in healthy controls. Methods HBECs were obtained during bronchoscopy from 10 patients with asthma (6 atopic and 4 non-atopic) and from healthy controls (n=9) and grown as undifferentiated cultures. HBECs were infected with parainfluenza virus (PIV)-3 (MOI 0.1) and rhinovirus (RV)-1B (MOI 0.1), or treated with medium alone. The cell supernatants were harvested at 8, 24, and 48 hours. IFN-α, CXCL10 (IP-10), and RANTES (CCL5) were analyzed by using Cytometric Bead Array (CBA), and interferon (IFN)-β and IFN-λ1 by ELISA. Gene expression of IFNs, chemokines, and IFN-regulatory factors (IRF-3 and IRF-7) was determined by using quantitative PCR. Results PIV3 and RV1B infections increased IFN-λ1 mRNA expression in HBECs from asthmatics and healthy controls to a similar extent, and virus-induced IFN-λ1 expression correlated positively with IRF-7 expression. Following PIV3 infection, IP-10 protein release and mRNA expression were significantly higher in asthmatics compared to healthy controls (median 36.03-fold). No differences in the release or expression of RANTES, IFN-λ1 protein and mRNA, or IFN-α and IFN-β mRNA between asthmatics and healthy controls were observed. However, when asthmatics were divided according to their atopic status, HBECs from atopic asthmatics (n=6) generated significantly more IFN-λ1 protein and demonstrated higher IFN-α, IFN-β, and IRF-7 mRNA expressions in response to PIV3 compared to non-atopic asthmatics (n=4) and healthy controls (n=9). In response to RV1B infection, IFN-β mRNA expression was lower (12.39-fold at 24 hours and 19.37-fold at 48 hours) in non-atopic asthmatics compared to atopic asthmatics. Conclusions The immune response of HBECs to virus infections may not be deficient in asthmatics, but seems to be modified by atopic status.

Cytomegalovirus DNA is highly prevalent in the blood of patients with asthma and is associated with age and asthma traits

Cytomegalovirus (CMV) IgG antibodies have been associated with inflammaging and immunosenescence. We aimed to assess the presence of CMV DNA in the blood of adult and elderly patients with bronchial asthma to establish potential association of CMV DNAemia with asthma and asthma characteristics. Eighty‐five elderly asthmatics, 74 younger asthma patients, and 114 age‐matched controls were recruited. The CMV DNA was detected using commercial artus assay in 10.7% of asthma patients, but was negative in all control individuals. The secondary assay identified CMV DNA in 41.5% of asthmatics and 13.3% of control subjects (P < .001). Presence of CMV DNA was associated with an increased risk of asthma and CMV DNA copy numbers correlated with some asthma traits, including respiratory parameters and exhaled breath nitric oxide. We conclude that CMV infection is associated with asthma and may contribute to the pathogenesis of asthmatic inflammation.

Platelet Reactivity in Patients With Stroke and Hyperlipidemia, GPIbα Assessment

The aim of this study was to assess platelet reactivity in patients after ischemic stroke and to investigate the influence of hyperlipidemia (HL) on platelet activity markers. A total of 41 patients after ischemic stroke were divided into the following 2 groups: patients with HL and patients with normolipidemia. Expression of CD42b on resting, thrombin-activated blood platelets, and fibrinogen level was assessed. The CD42b-positive platelets were analyzed using the flow cytometer, anti-CD61, and anti-CD42b monoclonal antibodies. The results confirmed increased platelet reactivity to thrombin in all patients after ischemic stroke manifested by significantly lower CD42b expression and percentage of CD42b(+) platelets after activation by thrombin. The influence of HL on the expression of CD42b on resting and thrombin-activated platelets was not found. However, increased level of fibrinogen but no influence of HL on fibrinogen concentration was observed in patients after ischemic stroke. Increased susceptibility to platelet agonists was found in patients after ischemic stroke in the convalescent phase.

sP- and sE-selectin in stroke patients with metabolic disorders

BACKGROUND Activation of platelets and endothelial cells plays an important role in the pathogenesis of atherosclerosis and thrombotic disorders. The aim of our study was to assess the relationship between the metabolic disorders and markers of platelet activity and vascular injury in patient with acute ischemic stroke. MATERIAL AND METHODS The study group consisted of 84 patients with acute non-lacunar ischemic stroke divided into four subgroups with: (1) normolipidemia and normoglycemia, (2) normolipidemia and hyperglycemia, (3) hyperlipidemia and normoglycemia, (4) hyperlipidemia and hyperglycemia. 21 healthy subjects served as controls. We analyzed the concentration of adhesion molecules sP-selectin and sE-selectin in serum collected from all studied groups using ELISA method. RESULTS We observed significantly higher sE- and sP-selectin concentration in patients with hyperglycemia and hyperlipidemia compared to both control subjects and patients with normolipidemia and normoglycemia. We did not observe additional effect of comorbid hyperlipidemia and hyperglycemia on studied markers. Soluble E- and P-selectin concentration correlated positively with LDL, TC and HbA1c level in all stroke patients. CONCLUSION Soluble E- and P-selectin, blood markers of vascular injury and platelet activation, could be useful in the assessment of atherothrombotic properties of hyperglycemia and hyperlipidemia in stroke patients.