Serum levels of inflammatory and regulatory cytokines in patients with hemorrhagic fever with renal syndrome

<p>Abstract</p> <p>Background</p> <p>Hantaviruses are the causative agents of two zoonotic diseases: hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). The pathogenesis of HFRS is poorly understood. However, it has been suggested that immune mechanisms, including cytokines, might have an important role in HFRS pathogenesis. Thus, the aim of our study was to investigate cytokine profiles in serum samples of HFRS patients from Slovenia and explore a possible correlation between cytokine levels and disease severity.</p> <p>Methods</p> <p>Acute-phase serum samples from 52 patients, diagnosed with DOBV infection, and 61 patients, diagnosed with PUUV infection, were included in this study. Patients were divided into two groups - severe or mild - based on disease severity. Levels of IL-10, IL-12, INF-γ and TNF-α were measured in the serum samples with commercial ELISA tests.</p> <p>Results</p> <p>Increased levels of IL-10, INF-γ, and TNF-α were found in almost all the serum samples tested. On average, higher concentrations were detected in patients infected with DOBV than PUUV. Furthermore, significantly higher levels of IL-10 (<it>P </it>= 0.001) and TNF-α (<it>P </it>= 0.003) were found in patients with a more severe clinical course of disease. The same association between IL-10 (<it>P </it>< 0.001) and TNF-α (<it>P </it>= 0.021), and the severity of the disease was observed also when only patients infected with DOBV were considered. No differences in cytokine concentrations according to disease severity were observed in patients infected with PUUV. Concentrations of serum IL-12 in HFRS patients were in the normal range, however, higher levels were detected in patients infected with PUUV than in patients infected with DOBV.</p> <p>Conclusions</p> <p>We suggest that imbalance in production of proinflammatory and regulatory cytokines might be in part responsible for a more severe course of HFRS.</p

Viral Load as Predictor of Crimean-Congo Hemorrhagic Fever Outcome

We used quantitative real-time reverse transcription–PCR to measure viral load in serum from 24 patients in Kosovo who had acute Crimean-Congo hemorrhagic fever. Viral load correlated with clinical disease and antibodies and could be used as a predictor of disease outcome

The complete genome sequence of a Crimean-Congo Hemorrhagic Fever virus isolated from an endemic region in Kosovo

The Balkan region and Kosovo in particular, is a well-known Crimean-Congo hemorrhagic fever (CCHF) endemic region, with frequent epidemic outbreaks and sporadic cases occurring with a hospitalized case fatality of approximately 30%. Recent analysis of complete genome sequences of diverse CCHF virus strains showed that the genome plasticity of the virus is surprisingly high for an arthropod-borne virus. High levels of nucleotide and amino acid differences, frequent RNA segment reassortment and even RNA recombination have been recently described. This diversity illustrates the need to determine the complete genome sequence of CCHF virus representatives of all geographically distinct endemic areas, particularly in light of the high pathogenicity of the virus and its listing as a potential bioterrorism threat. Here we describe the first complete CCHF virus genome sequence of a virus (strain Kosova Hoti) isolated from a hemorrhagic fever case in the Balkans. This virus strain was isolated from a fatal CCHF case, and passaged only twice on Vero E6 cells prior to sequence analysis. The virus total genome was found to be 19.2 kb in length, consisting of a 1672 nucleotide (nt) S segment, a 5364 nt M segment and a 12150 nt L segment. Phylogenetic analysis of CCHF virus complete genomes placed the Kosova Hoti strain in the Europe/Turkey group, with highest similarity seen with Russian isolates. The virus M segments are the most diverse with up to 31 and 27% differences seen at the nt and amino acid levels, and even 1.9% amino acid difference found between the Kosova Hoti and another strain from Kosovo (9553-01). This suggests that distinct virus strains can coexist in highly endemic areas

Interacting Roles of Immune Mechanisms and Viral Load in the Pathogenesis of Crimean-Congo Hemorrhagic Fever ▿

Until now, the pathogenesis of Crimean-Congo hemorrhagic fever (CCHF) has not been well described. However, it has been hypothesized that it could be a result of the direct injury of virus-infected tissues in combination with the indirect effects of host immune responses, including cytokines. To shed more light on the role of viral load and cytokines, differential influences of CCHF virus (CCHFV) RNA load, antibody response, and cytokine production on severity and outcome of the disease were studied in sera of 46 patients with confirmed acute CCHF from Kosovo. In this study, viral load proved to be strongly related to the severity and outcome of the disease, with higher viral loads detected in patients with fatal outcomes than in surviving patients. Also, patients with fatal outcome had on average a weaker antibody response, if one was present at all. High levels of interleukin-10 (IL-10), gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α) were associated with poor outcome, since detected concentrations were highest in patients with fatal outcome and lowest in patients with moderate disease course. Additionally, a positive linear dependence between viral load and these cytokines was observed. Interestingly, reduced levels of IL-12 were detected in all CCHF patients. Our study favors the hypothesis that CCHF could be a result of a delayed and downregulated immune response caused by IL-10, which leads to an increased replication and spread of CCHFV throughout the body. This consequently triggers increased production of IFN-γ and TNF-α, cytokines mediating vascular dysfunction, disseminated intravascular coagulation, organ failure, and shock

Prevalence of Crimean-Congo hemorrhagic fever virus in healthy population, livestock and ticks in Kosovo.

Crimean-Congo hemorrhagic fever (CCHF) is an acute, tick borne disease often associated with hemorrhagic presentations and high case fatality rate. Kosovo is a highly endemic area for CCHF, with a significant case fatality rate. The aim of our study was to determine the prevalence of CCHF in Kosovo. We tested 1105 serum samples from healthy population in both endemic and non-endemic areas in the country. Our results revealed a seroprevalence of 4.0% (range 0-9.3%) which is comparable to the seroprevalence in other countries. We show that seroprevalence is correlated to the disease incidence in each studied municipality. We also tested 401 animal sera (353 cow, 30 sheep, 10 goat and 8 chicken) in four endemic municipalities in Kosovo. We detected specific antibodies in all animals except in chicken. Seroprevalence in cows is comparable to other endemic areas and correlates to the seroprevalence in humans. No CCHF RNA could be detected in 105 tick samples obtained in 2012 and 2013. Sequencing of CCHFV positive ticks from 2001 revealed that the virus is most closely related to viral strains that were detected in CCHF patients from Kosovo. Results suggest that mild CCHF cases are most probably underdiagnosed and consequently that the burden of disease is higher than reported. Our study provides key information for CCHF surveillance and raises awareness for possible imported cases in CCHF non-endemic countries

Involvement of Ferroptosis in Diabetes-Induced Liver Pathology

Cell death plays an important role in diabetes-induced liver dysfunction. Ferroptosis is a newly defined regulated cell death caused by iron-dependent lipid peroxidation. Our previous studies have shown that high glucose and streptozotocin (STZ) cause β-cell death through ferroptosis and that ferrostatin-1 (Fer-1), an inhibitor of ferroptosis, improves β-cell viability, islet morphology, and function. This study was aimed to examine in vivo the involvement of ferroptosis in diabetes-related pathological changes in the liver. For this purpose, male C57BL/6 mice, in which diabetes was induced with STZ (40 mg/kg/5 consecutive days), were treated with Fer-1 (1 mg/kg, from day 1–21 day). It was found that in diabetic mice Fer-1 improved serum levels of ALT and triglycerides and decreased liver fibrosis, hepatocytes size, and binucleation. This improvement was due to the Fer-1-induced attenuation of ferroptotic events in the liver of diabetic mice, such as accumulation of pro-oxidative parameters (iron, lipofuscin, 4-HNE), decrease in expression level/activity of antioxidative defense-related molecules (GPX4, Nrf2, xCT, GSH, GCL, HO-1, SOD), and HMGB1 translocation from nucleus into cytosol. We concluded that ferroptosis contributes to diabetes-related pathological changes in the liver and that the targeting of ferroptosis represents a promising approach in the management of diabetes-induced liver injury