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As part of a large human biomonitoring study, we conducted occupational monitoring in a glass fibre factory inSlovakia. Shopfloor workers (n = 80), with a matched group of administrators in the same factory (n = 36), weremonitored for exposure to glass fibres and to polycyclic aromatic hydrocarbons (PAHs). The impact of occupationalexposure on chromosomal aberrations, DNA damage and DNA repair, immunomodulatory markers, andthe role of nutritional and lifestyle factors, as well as the effect of polymorphisms in metabolic and DNA repairgenes on genetic stability, were investigated. The (enzyme-modified) comet assay was employed to measure DNA strand breaks (SBs) and apurinic sites,oxidised and alkylated bases. Antioxidant status was estimated by resistance to H2O2-induced DNA damage. Baseexcision repair capacity was measured with an in vitro assay (based on the comet assay). Exposure of workers to fibres was low, but still was associated with higher levels of SBs, and SBs plus oxidisedbases, and higher sensitivity to H2O2. Multivariate analysis showed that exposure increased the risk of high levelsof SBs by 20%. DNA damage was influenced by antioxidant enzymes catalase and glutathione S-transferase(measured in blood). DNA repair capacity was inversely correlated with DNA damage and positively withantioxidant status. An inverse correlation was found between DNA base oxidation and the percentage ofeosinophils (involved in the inflammatory response) in peripheral blood of both exposed and reference groups.Genotypes of XRCC1 variants rs3213245 and rs25487 significantly decreased the risk of high levels of baseoxidation, to 0.50 (p = 0.001) and 0.59 (p = 0.001), respectively. Increases in DNA damage owing to glass fibre exposure were significant but modest, and no increases wereseen in chromosome aberrations or micronuclei. However, it is of concern that even low levels of exposure tothese fibres can cause significant genetic damage.

Higher probability of the development of Crohn’s disease (CD) and ulcerative colitis (UC) as a possible consequence of the north-south gradient has been recently suggested. Living far north or south of the equator is manifested in fluctuation of vitamin D (vitD) levels depending on the season in both healthy and affected individuals. In the present study we investigate the possible link between the seasonal serum vitD level to the microbial composition of the lower gut of Inflammatory Bowel disease (IBD) patients using 16S rRNA sequencing. Decrease of serum vitD level in winter/spring season in a cohort of 35 UC patients and 39 CD patients was confirmed. Low gut microbiota composition of patients with IBD correlated with the serum level of 25(OH)D that directly coupled to seasonal variability of the sunshine in the central European countries. It is supposed to be related to increased abundance of Actinobacteria and Proteobacteria in UC and Actinobacteria, Fusobacteria, Firmicutes and Bacteroidetes in CD. In summer/autumn period, we observed a reduction in abundance of bacterial genera typical for inflammation like Eggerthella lenta, Fusobacterium spp., Bacteroides spp., Collinsella aerofaciens, Helicobacter spp., Rhodococcus spp., Faecalibacterium prausnitzii; and increased abundance of Pediococcus spp. and Clostridium spp. and of Escherichia/Shigella spp.

Background: Human leukocyte antigen G (HLA-G) belongs to nonclassical HLA I molecule involving in the suppression of immune response. Besides its profound effect to induce fetal tolerance, HLA-G ex...

Ulcerative colitis (UC) and Crohn’s disease (CD) are the two main forms of inflammatory bowel disease (IBD). IBD is thought to result from an inappropriate and continuing inflammatory response to commensal microbes in a genetically susceptible host. One of hundreds independent SNPs connected to IBD pathogenesis are considered polymorphisms in the gene for vitamin D receptor (VDR). The purpose of the study was to investigate the association of VDR gene polymorphisms FokI, BsmI, ApaI, TaqI with disease susceptibility in 86 Slovak UC and 122 CD patients and in 155 controls. The distribution of VDR (FokI, BsmI, ApaI and TaqI) alleles and genotype variants in Slovak healthy population is analogous to those of other Caucasoid populations. The distributions of FokI genotypes in CD patients showed significant Hardy-Weinberg equilibrium (HWE) deviation (P = 0.0062) with considerable shortage of heterozygosity compared to controls (36.89 vs. 47.67%; OR = 0.5479; 95%CI = 0.3376–0.8892). We did not find any significant association of FokI, BsmI, ApaI and TaqI variants with localisation of UC or CD manifestation as well as the age of onset in case of Crohn’s disease. Our study showed for the first time in Slovak population that the FokI polymorphism can be involved in susceptibility to Crohn’s disease development. However, we did not find any association of FokI, BsmI, ApaI and TaqI SNPs with clinical features of CD and UC.

Background and Aims AB0 and HLA incompatibility between donor and recipient is one of the possible reasons of the low rate of living kidney donation in Slovakia. Method We present a retrospective analysis of living donor kidney transplantations (LDKT) in Slovakia including kidney paired donations. Results During the period from 2015 to 2019 there were 823 kidney transplantations, 81 (9,8%) were from living donors. Kidney paired donations are performed since 2005. Altogether 8 two-way paired exchanges were done in 3 transplant centers. The first exchange between two centers was carried out in 2015. A majority of the involved pairs (81%) were married couples, one exchange was initiated by compatible pair. Surgical procedures were simultaneous, cold ischemia times were comparable to other LDKT (median 162 vs 182 minutes). Two recipients had early acute rejection, 3-year graft survival is 100%. There were no serious complications in donors. The participation in EU project ENCKEP (European Network for Collaboration on Kidney Exchange Programmes) has led to the creation of national registry of incompatible pairs in 2018 and the standardization of medical and legal processes of paired exchanges. Conclusion Above reported experience is adequate prerequisite for the launch of nationally coordinated programme and international cooperation.

Enteroviruses (EVs) infections occur worldwide. Although, infections by these viruses are often asymptomatic and go unnoticed, they can be shed in stool for several weeks. The EVs are associated with sporadic outbreaks and a wide range of clinical symptoms, occasionally accompanied with fatal consequences. Presently in the Slovak Republic (SR) recreational waters are tested only for bacterial indicators. Our aim was to monitor EVs in recreational waters. Water samples were collected during the years 2012-2014 from different recreational natural lakes in Central and West regions of SR. The samples were concentrated by centrifugation using the two-phase separation method recommended by the World Health Organization (WHO) used for EVs surveillance in the treated sewage waste water. Each of the two phases collected from the samples was analysed by polymerase chain reaction for detection of EVs and primary sequencing was done. Our study demonstrated presence of EVs in three localities consecutively for three years, indicating a probability of constant local source of faecal contamination. This is the first monitoring report on the occurrence of EVs in the natural recreational waters in SR.

Human leukocyte antigen G (HLA-G) is a non-classical HLA class I protein with various immunosuppressive functions. Besides its profound effect to induce fetal tolerance, HLA-G has been also found to enhance graft acceptance. The aim of the study was to analyse the association between HLA-G 14 bp insertion/deletion polymorphism, soluble HLA-G level and kidney graft outcome in the Slovak population. We investigated 69 kidney transplant recipients aged 27–65 years. Out of this group, 37 recipients developed acute rejection, confirmed by biopsy, and 32 patients had stable allograft function. Plasma was obtained from recipients at 1 day before transplantation and analyzed by ELISA. Genotyping of HLA-G polymorphism was performed by PCR. Significantly higher pre-transplantation levels of sHLA-G were found in the group with stable allograft function in comparison to group with acute rejection (P = 0.0409). In the homozygous −14/−14 recipients with stable allograft function, significantly higher values of sHLA-G were determined in comparison to the recipients with acute rejection (P = 0.0052). The study revealed an association between 14 bp deletion polymorphism and soluble HLA-G level that is proportional to kidney graft acceptance. It is suggested that pre-transplantation levels of soluble HLA-G should be monitored as additional marker to predict kidney graft outcome.

Background The HLA-G molecule has a high potential to modulate immune response towards the improvement of graft survival after transplantation. In this work, we have analyzed the total HLA-G mRNA expression in graft tissues of dysfunctional transplanted kidneys. Material and methods We examined 84 kidney biopsy samples obtained from 65 renal transplant recipients with dysfunctional graft (50 males, 15 females; average age 46.8 ± 11.9 years). 52 specimens were with signs of acute rejection and 32 without any rejection characteristics (diagnosed as glomerulonephritis, ATN and IFTA). Patients with acute rejection were divided into three groups: antibody-mediated rejection (AMR; n = 23), T cell-mediated rejection (TCMR; n = 16) and combined antibody and T cell-mediated rejection (AMR + TCMR; n = 13). The biopsy samples were taken from a dysfunctional graft at different time periods after kidney transplantation. The relative expression of total HLA-G mRNA in biopsy specimens was determined by real time RT-PCR. The correlation between HLA-G mRNA expression and dysfunctional graft state was investigated. The impact of different factors (post-transplantation interval, gender, mismatch, induction therapy and cold ischemia time) on relative expression of total HLA-G mRNA was also studied. Results We have found that the levels of HLA-G transcripts in kidneys with rejection were higher than those in non-rejected but dysfunctional grafts (P = 0.0003). The highest levels of HLA-G mRNA were detected at combined AMR + TCMR rejection (P = 0.005). The time-course analysis of total HLA-G mRNA expression was also studied. In both dysfunctional graft groups (rejected and non-rejected) the lower levels of HLA-G transcripts were detected during early post-transplant period (1–3 months), however a substantial increase of HLA-G mRNA expression was observed after an extended period of time (> 3 months). It was also revealed that antibody induction therapy may reduce HLA-G expression (P = 0.0004) and in female samples were higher levels of HLA-G transcripts than those in male recipients (P = 0.003). It was found no significant impact of age, cold ischemic time, PRA (Panel Reactive Antibody) score, and a number of HLA-mismatches on HLA-G mRNA expression. Conclusions We have demonstrated that the expression of total HLA-G mRNA in renal grafts can be influenced by different factors such as clinical state of transplanted kidney, elapsed time after transplantation, gender and antibody induction therapy. We have proved that HLA-G mRNA expression was significantly higher in recipients with acute rejection in comparison to patients with dysfunctional but non-rejected grafts.

Despite recent advances in solid organ transplantations, an antibody mediated rejection caused by donor specific antibodies is still a major problem in kidney graft survival. Besides HLA-induced humoral response, antibodies against MICA antigens have recently attracted attention because of their possible role in graft rejection. The aim of our study was to establish whether renal recipients produce antibodies against MICA molecules due to the transplantation and if they are specific for MICA antigens of the donors. MICA antibody screening was performed in 124 kidney recipient sera. 22 sera, that were found to be MICA antibody positive, were further examined for MICA antibody profiles and compared with donor MICA alleles. The analysis of MICA antibody positive sera showed mostly more complex reactivity patterns. A significant fraction of patient sera (59%) reacted not only with the donor MICA antigens, but also with other MICA patterns. A match between antibody specificities and MICA antigens was observed in 41% of renal recipients only. On the other hand, as much as in 36% of recipient sera were detected antibodies against their own MICA molecules. We did not prove a complete correlation between the recipient MICA antibody specificities and MICA antigens of the donor. We assume that MICA antibody induction occurs not only due to the allogeneic stimulation itself but also due to other factors that need to be elucidated.

Copper is known to induce oxidative stress in a number of models. It was shown that many pathophysiological events were associated with oxidative stress. Further, oxidative stress can increase gene expression of cytokines and of metalloproteinases. We previously found that copper toxic effects in isolated perfused rat livers were associated with significant oxidative stress (as assessed by lipid peroxidation, protein oxidation and oxidative DNA damage, particularly at concentration of 0.03 mM of Cu2+ in the perfusate). Here we investigated gene expression of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10); matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) in frozen liver tissue samples by the real-time PCR assay. Compared to controls, copper at concentration of 0.01 mM did not affect gene expression of TNF-α, IL-10, MMP-2 and MMP-9, whereas copper at concentration of 0.03 mM significantly decreased gene expression of all the four TNF-α, IL-10, MMP-2 and MMP-9 by 69%, 81%, 43%, and 62%, respectively. These results suggest that copper-induced oxidative stress in the isolated rat liver can lead to the suppression of gene expression. Because TNF-α and metalloproteinases are involved also in liver regeneration, the suppression of these genes by copper may be one of the mechanisms by which acute intoxication of animals and humans with copper may impair regenerative capability of the liver.

It has been suggested that HLA-G antigens may provide tumor cells with an effective immune escape mechanism. So far mostly solid tumors have been analyzed; HLA-G antigen was only exceptionally detected. To further examine HLA-G expression, patients were chosen with different forms of leukemia: AML (25), CML (4), ALL (9), CLL (8), HCL (2) and NHL (3). Using flow cytometry with three HLA-G specific mAbs (87G, 01G and MEM-G/9), western blotting with two specific mAbs (4H84 and MEM-G/1) and RT-PCR, neither HLA-G antigen nor mRNA for any HLA-G isoform was detected. These results strongly suggest that HLA-G antigen is not expressed in freshly isolated human leukemia cells and therefore is not involved in their escape from immune attack.

Established risk factors for cardiovascular diseases (CVD) may be moderated by genetic variants. In 2403 unrelated individuals from general practice (mean age 40.5 years), we evaluated the influence of 15 variants in 12 candidate genes on quantitative traits (QT) associated with CVD (body mass index, abdominal obesity, glucose, serum lipids, and blood pressure). Prior to multiple testing correction, univariate analysis associated APOE rs429358, rs7412 and ATG16L1 rs2241880 variants with serum lipid levels, while LEPR rs1137100 and ATG16L1 rs2241880 variants were linked to obesity related QTs. After taking into account confounding factors and correcting for multiple comparisons only APOE rs429358 and rs7412 variants remained significantly associated with risk of dyslipidemia. APOE rs429358 variant almost tripled the risk in homozygous subjects (OR = 2.97; 95% CI 1.09-8.10, p < 0.03) and had a lesser but still highly significant association also in heterozygous individuals (OR = 1.67; 95% CI 1.24-2.10; p < 0.001). Associations with hypertension, diabetes mellitus, and metabolic syndrome were not significant after Bonferroni correction. The influence of genetic variation is more evident in dyslipidemia than in other analyzed QTs. These results may contribute to strategic research aimed at including genetic variation in the set of data required to identify subjects at high risk of CVD.

In this study, we analyzed HLA-G expression in serum and graft biopsies of renal transplant patients to find out whether there is any relationship between HLA-G and renal graft acceptance. The transplant patients were divided into two groups: those without any rejection episode ( n = 32) and those with acute rejection ( n = 33). Patient sera were collected 1 day before and at various intervals after transplantation. Soluble HLA-G (sHLA-G) in serum was determined using ELISA. In time-course experiment we found that in all patients (with and without rejection) the pre-transplantation level of sHLA-G declined in the early post-transplant period (1–2 weeks). In sera collected over 1–12 months after transplantation, a substantial increase of sHLA-G was detected in patients without rejection while no change or additional decline was observed in recipients with graft rejection. In sera collected after more than 1 year post-transplantation, sHLA-G levels increased in both groups of patients (with or without graft rejection). The time-course of serum sHLA-G antigens in patients with graft rejection was in good correlation with the course of total HLA-G mRNA determined in graft biopsy samples isolated from patients with acute rejection. We further demonstrated that serum sHLA-G values were significantly higher in patients without graft rejection than with rejection ( P = 0.0058). This observation supports the assumption that the increase of serum sHLA-G may contribute to allograft acceptance.

We very recently showed (using a blood-free perfusion model) that cold preservation sensitized rat hepatocyte functions to rewarming ischemic injury and that the injury can be prevented by repleting high-energy adenylates in the liver by short-term oxygenated warm reperfusion. Here we investigated whether short-term reperfusion after the preservation period can improve hepatic graft function in a blood reperfusion model. Eighteen-hour cold-preserved rat livers either untreated (Group A) or pretreated by 30-min oxygenated warm reperfusion after preservation (Group B) were subjected to 20-min ischemic rewarming and then reperfused with blood. Livers in Group B compared to Group A exhibited approx. three times increased bile production and bromosulfophthalein excretion, nearly 7-fold decreased swelling, and 1.2-fold improved blood flow. These results suggest that repletion of the energy by short-term oxygenated reperfusion after prolonged preservation may improve markedly initial hepatic graft function.

We have found that 4H84 monoclonal antibody (mAb) used for detection of β 2 m free HLA-G molecules also binds to free heavy chains of classical HLA class I antigens generated on the cell surface by mild acid treatment. Here we demonstrate that β 2 m free classical HLA class I molecules induced on the surface of activated lymphocytes not expressing HLA-G also bind 4H84 mAb. These results demonstrate that 4H84 mAb should be used for detection of HLA-G in cells and tissues with backing by other HLA-G specific mAbs.

Although tumor necrosis factor-alpha has been implicated in liver injury after both warm ischemia- and cold ischemia-reperfusion, it is unclear whether reactivity of the liver to these stimuli is similar with regard to cytokine expression. Here we compare the effects of warm and cold ischemia on tumor necrosis factor-alpha expression and test the hypothesis that cold ischemia preceding warm ischemia causes overexpression of this cytokine. Rat livers were flushed out with University of Wisconsin solution and subjected to varying periods of warm ischemia, cold ischemia, or cold ischemia plus warm ischemia followed by reperfusion using a blood-free perfusion model. Tumor necrosis factor-alpha and interleukin-10 release into the perfusate and bile were measured by ELISA, and expression of these cytokines and that of c-fos, c-jun, and c-myc were studied by reverse-transcriptase polymerase chain reaction. We found high levels of tumor necrosis factor-alpha in the perfusates of livers subjected to warm ischemia-reperfusion, whereas minimal or no tumor necrosis factor-alpha was detected in livers subjected to cold ischemia-reperfusion or to cold ischemia plus warm ischemia-reperfusion. Reverse-transcriptase polymerase chain reaction confirmed the above findings and showed that immediate early genes were expressed in reperfused groups of livers. Measurements of cytokine release into bile showed that neither tumor necrosis factor-alpha nor interleukin-10 were upregulated by cold ischemia-reperfusion. The results suggest that (1) warm ischemia- and cold ischemia-reperfusion of rat liver lead to very different outcomes with regard to tumor necrosis factor-alpha expression and (2) cold ischemia preceding warm ischemia prevents upregulation of tumor necrosis factor-alpha.