Andreas Mitterbauer

Discrimination of clinical stages in non-small cell lung cancer patients by serum HSP27 and HSP70: a multi-institutional case-control study.

INTRODUCTION Lung cancer represents a major healthcare problem. Accordingly, there is an urgent need to identify serum biomarkers for early diagnosis of lung pathology. We have recently described that patients with manifest COPD evidence elevated levels of heat shock proteins (HSPs). Based on these data, we speculated whether HSPs are also increased in patients with diagnosed lung cancer. METHODS Serum levels of HSP27, phospho-HSP27 (pHSP27) and HSP70 in patients with non-small cell lung cancer (NSCLC) diagnosed at an early (stages I-II, n=37) or advanced (stages IIIA-IV, n=72) stage were determined by using ELISA. Healthy smokers (n=24), healthy never-smoker volunteers (n=33) and COPD patients (n=34) according to GOLD classification served as control population. RESULTS Serum levels of HSP27 were elevated in patients with NSCLC diagnosed at an early or advanced stage when compared with both healthy control groups (P<0.005 and P<0.0001 respectively). Statistically significant differences were furthermore found between the groups of patients with early vs. advanced stage NSCLC (P=0.0021). Serum levels of HSP70 were also significantly elevated in patients with NSCLC diagnosed at an early or at an advanced stage when compared with either healthy control groups (P=0.0028 and P<0.0001 respectively). In univariate logistic regression models including healthy subjects and patients with NSCLC, HSP70 had an area under the curve (AUC) of 0.779 (P<0.0001) and HSP27 showed an AUC of 0.870 (P<0.0001). CONCLUSION Our data suggest that serum HSP27 levels might serve as a possible tool to discriminate between early and advanced stages NSCLC.

Analysis of the Secretome of Apoptotic Peripheral Blood Mononuclear Cells: Impact of Released Proteins and Exosomes for Tissue Regeneration

We previously showed that, when peripheral blood mononuclear cells (PBMCs) were stressed with ionizing radiation, they released paracrine factors that showed regenerative capacity in vitro and in vivo. This study aimed to characterize the secretome of PBMCs and to investigate its biologically active components in vitro and vivo. Bioinformatics analysis revealed that irradiated PBMCs differentially expressed genes that encoded secreted proteins. These genes were primarily involved in (a) pro-angiogenic and regenerative pathways and (b) the generation of oxidized phospholipids with known pro-angiogenic and inflammation-modulating properties. Subsequently, in vitro assays showed that the exosome and protein fractions of irradiated and non-irradiated PBMC secretome were the major biological components that enhanced cell mobility; conversely, secreted lipids and microparticles had no effects. We tested a viral-cleared PBMC secretome, prepared according to good manufacturing practice (GMP), in a porcine model of closed chest, acute myocardial infarction. We found that the potency for preventing ventricular remodeling was similar with the GMP-compliant and experimentally-prepared PBMC secretomes. Our results indicate that irradiation modulates the release of proteins, lipid-mediators and extracellular vesicles from human PBMCs. In addition our findings implicate the use of secretome fractions as valuable material for the development of cell-free therapies in regenerative medicine.

Standard donor lung procurement with normothermic ex vivo lung perfusion: A prospective randomized clinical trial

BACKGROUND Ex vivo lung perfusion (EVLP) was primarily developed for evaluation of impaired donor lungs. The good clinical results raise the question for its possible impact on lungs meeting standard criteria. Before application of EVLP on such lungs enters routine clinical practice, it must be demonstrated whether EVLP would affect or improve outcome when used in standard donor lungs. We performed a prospective randomized trial to investigate the role of EVLP in standard lung transplantation (Tx). METHODS This prospective randomized clinical trial compared patients who underwent Tx with ex vivo evaluated donor lungs with an equivalent patient population without previous EVLP. RESULTS From October 2013 to May 2015, 193 lung Tx were performed at the Medical University of Vienna. During this period, 80 recipient/donor pairs that met the inclusion criteria were included in this trial, 41 pairs in the control group, and 39 in the EVLP group. In the EVLP group, 4 lungs (10.2%) ultimately did not qualify for Tx and were rejected for lung Tx owing to technical reasons (n = 2) and quality criteria (n = 2). Donor and recipient characteristics were comparable in both groups. Total cold ischemic time in the EVLP group was significantly longer for both implanted lungs (first side, 372 minutes vs 291 minutes, p < 0.001; second side, 437 minutes vs 370 minutes, p = 0.001); median duration of surgery showed no differences (277 minutes vs 275 minutes). Median oxygen partial pressure/fraction of inspired oxygen ratio at 24 hours after Tx was 516 (range, 280-557) in the EVLP group and 491 (range, 352-575) in the control group (p = 0.63). Incidence of primary graft dysfunction >1 was lower in the EVLP group at all time points compared with the control group (24 hours, 5.7% vs 19.5%, p = 0.10), and need for post-operative prolonged extracorporeal membrane oxygenation was lower in the EVLP group (5.7% vs 12.2%, p = 0.44). Short-term clinical outcomes did not differ between recipients in the 2 groups. Patients remained intubated (1.6 days vs 1.6 days, p = 0.67), in the intensive care unit (6 days vs 6 days, p = 0.76), and in the hospital (23 days vs 19 days, p = 0.42) for a comparable period of time. The 30-day survival was 97.1% vs 100% (p = 0.46). CONCLUSIONS This study provides evidence that EVLP can safely be used in standard donor lungs. Functional results and perioperative outcome are comparable to those achieved with standard donor lung preservation techniques. As an evaluation tool, EVLP allows clinicians to identify and to possibly exclude lungs with functional impairment. Finally, EVLP can safely extend total preservation time.

Mononuclear cell secretome protects from experimental autoimmune myocarditis

Abstract Aims Supernatants of serum-free cultured mononuclear cells (MNC) contain a mix of immunomodulating factors (secretome), which have been shown to attenuate detrimental inflammatory responses following myocardial ischaemia. Inflammatory dilated cardiomyopathy (iDCM) is a common cause of heart failure in young patients. Experimental autoimmune myocarditis (EAM) is a CD4+ T cell-dependent model, which mirrors important pathogenic aspects of iDCM. The aim of this study was to determine the influence of MNC secretome on myocardial inflammation in the EAM model. Methods and results BALB/c mice were immunized twice with an alpha myosin heavy chain peptide together with Complete Freund adjuvant. Supernatants from mouse mononuclear cells were collected, dialysed, and injected i.p. at Day 0, Day 7, or Day 14, respectively. Myocarditis severity, T cell responses, and autoantibody formation were assessed at Day 21. The impact of MNC secretome on CD4+ T cell function and viability was evaluated using in vitro proliferation and cell viability assays. A single high-dose application of MNC secretome, injected at Day 14 after the first immunization, effectively attenuated myocardial inflammation. Mechanistically, MNC secretome induced caspase-8-dependent apoptosis in autoreactive CD4+ T cells. Conclusion MNC secretome abrogated myocardial inflammation in a CD4+ T cell-dependent animal model of autoimmune myocarditis. This anti-inflammatory effect of MNC secretome suggests a novel and simple potential treatment concept for inflammatory heart diseases.

Increased serum levels of HSP27 as a marker for incipient chronic obstructive pulmonary disease in young smokers

Background: Although chronic obstructive pulmonary disease (COPD) is amongst the leading causes of morbidity and mortality, no biomarkers for its early detection are known. We have recently demonstrated that COPD is accompanied by elevated serum heat shock protein (HSP) 27 levels as compared to a control population. Objectives: In an open prospective study, we investigated whether elevated HSP27 levels are associated with the early radiological signs of COPD, i.e. air trapping (AT), emphysema (E) and impaired lung function. Methods: In total, 120 apparently healthy smokers underwent lung function testing and serum sampling. Serum levels of HSP27, phospho-HSP27, CXCR2 chemokines and proteins related to inflammation, tissue remodeling and apoptosis were evaluated by ELISA. Of these 120 subjects, 94 voluntarily underwent a high-resolution computed tomography scan. Results: AT or AT and E were detected in 57.45%. Subjects with AT and E (n = 23) showed significantly higher HSP27 levels than those without any pathology [i.e. nothing abnormal detected (NAD)] (4,618 ± 1,677 vs. 3,282 ± 1,607 pg/ml; p = 0.0081). In a univariate logistic regression model including NAD and AT and E, the area under the curve of HSP27 in the receiver-operating-characteristic curve was 0.724, (0.594–0.854, 95% CI; p = 0.0033). Interestingly, proinflammatory IL-8 was elevated in those subjects with evidence of AT and E compared to those with AT and NAD. Lung function did not correlate with increased HSP27 levels or pathological radiological findings. Conclusions: HSP27 serum levels correlated with the early radiological signs of COPD, whereas lung function did not match with radiological findings or HSP27 serum levels. Serum HSP27 levels may serve as a potential marker to identify the early signs of COPD independent of lung function in young smokers.

The secretome of apoptotic human peripheral blood mononuclear cells attenuates secondary damage following spinal cord injury in rats

After spinal cord injury (SCI), secondary damage caused by oxidative stress, inflammation, and ischemia leads to neurological deterioration. In recent years, therapeutic approaches to trauma have focused on modulating this secondary cascade. There is increasing evidence that the success of cell-based SCI therapy is due mainly to secreted factors rather than to cell implantation per se. This study investigated peripheral blood mononuclear cells as a source of factors for secretome- (MNC-secretome-) based therapy. Specifically, we investigated whether MNC-secretome had therapeutic effects in a rat SCI contusion model and its possible underlying mechanisms. Rats treated with MNC-secretome showed substantially improved functional recovery, attenuated cavity formation, and reduced acute axonal injury compared to control animals. Histological evaluation revealed higher vascular density in the spinal cords of treated animals. Immunohistochemistry showed that MNC-secretome treatment increased the recruitment of CD68(+) cells with concomitant reduction of oxidative stress as reflected by lower expression of inducible nitric oxide synthase. Notably, MNC-secretome showed angiogenic properties ex vivo in aortic rings and spinal cord tissue, and experiments showed that the angiogenic potential of MNC-secretome may be regulated by CXCL-1 upregulation in vivo. Moreover, systemic application of MNC-secretome activated the ERK1/2 pathway in the spinal cord. Taken together, these results indicate that factors in MNC-secretome can mitigate the pathophysiological processes of secondary damage after SCI and improve functional outcomes in rats.

Paracrine Factors from Irradiated Peripheral Blood Mononuclear Cells Improve Skin Regeneration and Angiogenesis in a Porcine Burn Model

Burn wounds pose a serious threat to patients and often require surgical treatment. Skin grafting aims to achieve wound closure but requires a well-vascularized wound bed. The secretome of peripheral blood mononuclear cells (PBMCs) has been shown to improve wound healing and angiogenesis. We hypothesized that topical application of the PBMC secretome would improve the quality of regenerating skin, increase angiogenesis, and reduce scar formation after burn injury and skin grafting in a porcine model. Full-thickness burn injuries were created on the back of female pigs. Necrotic areas were excised and the wounds were covered with split-thickness mesh skin grafts. Wounds were treated repeatedly with either the secretome of cultured PBMCs (SecPBMC), apoptotic PBMCs (Apo-SecPBMC), or controls. The wounds treated with Apo-SecPBMC had an increased epidermal thickness, higher number of rete ridges, and more advanced epidermal differentiation than controls. The samples treated with Apo-SecPBMC had a two-fold increase in CD31+ cells, indicating more angiogenesis. These data suggest that the repeated application of Apo-SecPBMC significantly improves epidermal thickness, angiogenesis, and skin quality in a porcine model of burn injury and skin grafting.

Low Tidal Volume Ventilation during Cardiopulmonary Bypass Reduces Postoperative Chemokine Serum Concentrations

BACKGROUND Open-heart surgery with cardiopulmonary bypass (CPB) is associated with a generalized immune response and postoperative lung dysfunction. Chemokines are involved in the pathogenesis of postoperative lung dysfunction. We investigated whether continued mechanical ventilation during CPB has an impact on chemokine serum concentrations. METHODS A total of 30 patients undergoing coronary artery bypass graft operation were randomized to either continuous ventilated group (n=15) or nonventilated group (n=15). Blood samples were drawn at the beginning and at the end of surgery and on the 5 consecutive days. Serum CCL2, CCL4, and CCL20 concentrations were measured and given as mean ± standard deviation. RESULTS Chemokine concentrations were elevated at the end of surgery in both groups. CCL2 and CCL4 levels returned to baseline on postoperative day (POD)-1 in the ventilation group and stayed elevated in the nonventilation group. CCL4 serum levels were significantly lower in ventilated-group patients on POD-1 (10.9 [39.0] vs. 153.2 [168.1]; p=0.005), POD-2 (16.8 [36.8] vs. 147.9 [165.4]; p=0.019), POD-3 (14.2 [24.0] vs. 97.9 [87.1]; p=0.005), and POD-5 (6.5 [25.0] vs. 33.6 [38.4]; p=0.045). CONCLUSION Continued mechanical ventilation during CPB results in reduced CCL4 concentrations on POD-1 to -5.

Non-professional marathon running: RAGE axis and ST2 family changes in relation to open-window effect, inflammation and renal function

Conflicting data exist on the relevance of marathon (M) and half marathon (HM) running for health. The number of non-professional athletes finishing M and HM events is steadily growing. In order to investigate molecular changes occurring in amateur athletes, we enrolled 70 non-professional runners finishing a single M (34) or HM (36) event at baseline, the finish line and during recovery, and 30 controls. The measurement of the Receptor for Advanced Glycation Endproducts, Interleukin 1 receptor antagonist, ST2 and cytokeratin 18 was combined with molecules measured during clinical routine. Results were analyzed in the light of blood cell analysis, lactate measurements, correction for changes in plasma volume and body composition assessments. There were intrinsic differences in body mass index, abdominal body fat percentage and training time between M and HM runners. C-reactive protein changes in M and HM runners. While soluble RAGE, AGEs and ST2 increased immediately after the race in HM runners, HMGB1 increased in HM and M after the race and declined to baseline after a recovery period. We give insights into the regulation of various molecules involved in physical stress reactions and their possible implications for the cardiovascular system or renal function.

Continued mechanical ventilation during coronary artery bypass graft operation attenuates the systemic immune response

OBJECTIVES Cardiopulmonary bypass (CPB) is known to induce a short pro- and long-lasting anti-inflammatory immune response. The anti-inflammatory protein soluble ST2 (sST2) may be involved in the pathogenesis of postoperative immune dysfunction. We investigated whether continued mechanical ventilation during CPB has an impact on postoperative serum sST2 and cytokine release. METHODS Thirty patients undergoing conventional coronary artery bypass graft (CABG) operation were randomized into a ventilated on CPB (VG; n = 15) and non-ventilated on CPB group (NVG; n = 15). Blood samples were drawn at the beginning and at the end of surgery, and at the 5 consecutive days. sST2, IL-4, IL-10, IgM, IgG, IL-6 and endotoxin were measured by ELISA. Data are given as mean standard deviation (SD). A Mann-Whitney U-test was used for statistical analysis. RESULTS Serum levels of sST2 and IL-10 were significantly higher in the NVG when compared with the VG at the first postoperative day (POD-1) [sST2 pg/ml: 1366.4 (433) (VG) vs 2296.3 (1795.5) (NVG) P = 0.029; IL-10 pg/ml: 10.7 (4.0) (VG) vs 15.4 (6.8) (NVG) P = 0.038]. In addition, the secretion of proinflammatory IL-6 was slightly reduced in the VG at POD-1 [IL-6 pg/ml: 83.1 (52.5) (VG) vs 110.2 (42.3) (NVG) P = 0.033]. IL-4, endotoxin, IgM and IgG showed no differences between groups. CONCLUSION These data suggest that continued mechanical ventilation during CABG attenuates inflammatory and anti-inflammatory immune responses after CPB. Continued mechanical ventilation may have beneficial effects in the attenuation of the CPB-induced immune activation.