[Investigation of hsa-miR-1908 and hsa-miR-144 Expression Levels in Crimean-Congo Hemorrhagic Fever Patients]. / Kirim-Kongo Kanamali Atesi Hastalarinda hsa-miR-1908 ve hsa-miR-144 Ifade Düzeylerinin Arastirilmasi.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne zoonotic viral disease. MicroRNAs (miRNAs), which play an important role in the regulation of gene expression, are involved in many processes essential for cell life such as development, differentiation, survival, apoptosis and aging. If miRNAs fail to fulfill their functions, they cause susceptibility to many diseases, including viral infections or cause the disease to be experienced in different clinical situations, such as severe or mild. In this study, we aimed to determine the expression levels of hsa-miR-144 and hsa-miR-1908 in CCHF patients and to compare the results in different clinical courses of CCHF disease. In this study, expression levels of hsa-miR-144 and hsa-miR-1908 were detected by quantitative reverse transcription polymerase chain reaction (RT-qPCR) in blood samples obtained from 60 CCHF patients and 40 healthy individuals. We also investigated the differences in the expression levels of the microRNAs between patients with severe and non-severe disease or between patients who died and survived. Quantitative polymerase chain reaction data were uploaded to the "Data Analysis Center" (Qiagen, Germany) and analyzed using the ΔΔCq (ΔΔCt) method. p value was calculated according to Student's t test for genes in the study groups. The expression level of hsa-miR-144 decreased (fold change= 0.09) and the expression level of hsa-miR-1908 increased 1.44-fold in CCHF patients compared to the control group. The expression of hsa-miR-144 and hsa-miR-1908 increased 2 and 2.36-fold, respectively, in severe patients compared to non-severe patients. The expression levels of hsa-miR-144 and hsa-miR-1908 were 16.3- and 14.3-fold higher, respectively, in fatal cases compared to surviving patients and these results were statistically significant. In addition, the expression level of hsa-miR-144 was significantly decreased in patients with low leukocyte counts and the expression level of hsa-miR-1908 was significantly increased in patients with prolonged prothrombin time (PT). This is the first study in the literature investigating the expression level of hsa-miR-1908 in CCHF patients. In conclusion, the data of this study suggest that hsa-miR-144 and hsa-miR-1908 may be important biomarkers in predicting the prognosis and clinical course of CCHF disease.

Genetic background of adaptation of Crimean-Congo haemorrhagic fever virus to the different tick hosts.

Crimean-Congo haemorrhagic fever orthonairovirus (CCHFV) is a negative-sense, single-stranded RNA virus with a segmented genome and the causative agent of a severe Crimean-Congo haemorrhagic fever (CCHF) disease. The virus is transmitted mainly by tick species in Hyalomma genus but other ticks such as representatives of genera Dermacentor and Rhipicephalus may also be involved in virus life cycle. To improve our understanding of CCHFV adaptation to its tick species, we compared nucleotide composition and codon usage patterns among the all CCHFV strains i) which sequences and other metadata as locality of collection and date of isolation are available in GenBank and ii) which were isolated from in-field collected tick species. These criteria fulfilled 70 sequences (24 coding for S, 23 for M, and 23 for L segment) of virus isolates originating from different representatives of Hyalomma and Rhipicephalus genera. Phylogenetic analyses confirmed that Hyalomma- and Rhipicephalus-originating CCHFV isolates belong to phylogenetically distinct CCHFV clades. Analyses of nucleotide composition among the Hyalomma- and Rhipicephalus-originating CCHFV isolates also showed significant differences, mainly in nucleotides located at the 3rd codon positions indicating changes in codon usage among these lineages. Analyses of codon adaptation index (CAI), effective number of codons (ENC), and other codon usage statistics revealed significant differences between Hyalomma- and Rhipicephalus-isolated CCHFV strains. Despite both sets of strains displayed a higher adaptation to use codons that are preferred by Hyalomma ticks than Rhipicephalus ticks, there were distinct codon usage preferences observed between the two tick species. These findings suggest that over the course of its long co-evolution with tick vectors, CCHFV has optimized its codon usage to efficiently utilize translational resources of Hyalomma species.

Association of eNOS gene 4a/4b VNTR and T786C polymorphism with Crimean-Congo hemorrhagic fever.

The most common viral hemorrhagic fever is Crimean-Congo hemorrhagic fever (CCHF). Endothelial nitric oxide synthase (eNOS) gene polymorphisms have been linked to both hemorrhagic fevers and viral diseases. The study's goal is to evaluate if the eNOS gene 4a/4b and T786C polymorphisms are related to CCHF. The study included 54 CCHF RNA-positive patients and 60 control subjects. The Bosphore CCHF virus Quantification Kit v1 was used to obtain CCHF RNA, and the Magnesia 16 isolation device was used to isolate DNA (Anatolia Gene works, Turkey). Polymerase chain reaction and restriction fragment length polymorphism were used to genotype the samples. The frequency of the eNOS 4a/4a, 4a/4b, and 4 b/4b genotypes in patients and the control was 6.6% versus 1.7%, 37.0% versus 43.3%, and 57.4% versus 55%, respectively. 4a: 24.07% of patients and 23.33% of controls; and 4 b: 75.92% of patients and 76.66% of controls. The frequency of the eNOS-786 T/C, T/T, T/C, and C/C genotypes in patients and the control group was 35.2% versus 68.3%; 51.9% versus 26.73%; and 13.0% versus 5.0%, respectively. The allele and genotype frequencies of the eNOS T786C variant differ statistically between patients and the control (p < 0.05). The eNOS T786C variant could be a genetic determinant for susceptibility to CCHF. To our knowledge, this is the first study to figure out the association between eNOS gene T786C polymorphisms and CCHF disease.

Methylene-tetrahydrofolate reductase gene C677T and A1298C polymorphisms as a risk factor for Crimean-Congo hemorrhagic fever.

Crimean-Congo hemorrhagic fever (CCHF) is a deadly viral disease. Methylene-tetrahydrofolate reductase (MTHFR) has an important role in folate metabolism, and also in the formation of new cells, DNA synthesis, repair and methylation. We aimed to examine the relationship between MTHFR gene C677T (Ala222Val, rs1801133) and A1298C (Glu429Ala, rs1801131) polymorphisms with CCHF in a Turkish population. Totally 273 participants were included in the current study. One hundred forty-one participants were CCHF patients and one hundred thirty-two participants were healthy controls. The polymerase chain reaction (PCR) and further restriction fragment length polymorphism (RFLP) assays were applied to determine the genotypes of MTHFR polymorphisms. We did not find any differences between the CCHF patients and healthy controls in terms of allele and genotype distributions of both the C677T and A1298C polymorphisms. In composite genotype analysis between different groups, the frequency of CT-AA composite genotype, which is formed by C677T-A1298C polymorphisms, was found to be significantly higher in Mild CCHF patients compared to both Severe CCHF patients and controls (p = 0.036 and p = 0.008, respectively). In conclusion, in this study, we found a relationship between CCHF and MTHFR gene polymorphisms. CT-AA composite genotype of MTHFR gene C677T and A1298C polymorphisms showed a predisposition to Mild CCHF.

Long noncoding RNA expression analysis in Crimean Congo hemorrhagic fever patients.

Crimean Congo hemorrhagic fever (CCHF) is an acute viral infection that can cause death. The detection of host transcriptome is important for understanding differences in the pathogenesis of the disease. Long noncoding RNAs (lncRNAs) regulate gene expression in different biological processes. They have also emerged as key molecules for therapeutic targets. We investigated the lncRNA gene expression profiles by utilizing the microarray for the first time in CCHF. LncRNAs were determined by the comparisons between case-control, fatal case-control, and fatal case-nonfatal cases. Quantitative polymerase chain reaction was applied to validate the microarray results of some lncRNAs. In our study, 39 lncRNAs (5 downregulated and 34 upregulated) were found to be significantly regulated in the cases when compared to the controls (p < 0.05; FC ≥ 2). One hundred ten lncRNAs exhibited a statistically significant difference between fatal cases and controls. FER1L4, ECRP, and LOC100133669 are important lncRNAs in both case and fatal case groups compared with controls. These lncRNAs may be considered important therapeutic targets for the CCHF in further studies.

MicroRNA analysis from acute to convalescence in Crimean Congo hemorrhagic fever.

Crimean Congo hemorrhagic fever (CCHF) is one of the most important viral infections and is caused by Crimean Congo hemorrhagic fever orthonairovirus (CCHFV). Severity of CCHF can vary from a mild and nonspecific illness to a severe disease with fatal outcomes. MicroRNAs (miRNAs) have an increasing impact on the different pathways of viral infections. Within the transition process from acute phase to convalescence with 18 CCHF patients, we investigated the impacts on miRNA via microarray for the first time. We also compared miRNA gene expression in 16 severe and 15 mild cases. We identified Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathways associated with significant miRNAs utilizing DIANA TOOLS mirPath v.3. In this study, miR-15b-5p and miR-29a-3p were significantly downregulated in statistical terms; miR-4741, miR-937-5p, miR-6068, miR-7110-5p, miR-6126, and miR-7107-5p were upregulated in acute cases in comparison with convalescent patients (p ≤ .05). In total, 28 miRNAs (8 downregulated, 20 upregulated) were differentially expressed in severe CCHF patients as compared with mild cases (p ≤ .05). Whereas miR-6732-3p, miR-4436b-5p, miR-483-3p, and miR-6807-5p had the highest downregulation, miR-532-5p, miR-142-5p, miR-29c-3p, and let-7f-5p had the highest upregulation in severe patients in comparison with mild cases. Consequently, we determined that CCHF-induced miRNAs are associated with antiviral and proinflammatory pathways in acute and severe cases. In comparison with convalescence, these miRNAs in acute period may be therapeutic targets.

Purification of Crimean-Congo hemorrhagic fever virus nucleoprotein and its utility for serological diagnosis.

Crimean-Congo hemorrhagic fever virus (CCHFV) causes a zoonotic disease, Crimean-Congo hemorrhagic fever (CCHF) endemic in Africa, Asia, the Middle East, and Southeastern Europe. However, the prevalence of CCHF is not monitored in most of the endemic countries due to limited availability of diagnostic assays and biosafety regulations required for handling infectious CCHFV. In this study, we established a protocol to purify the recombinant CCHFV nucleoprotein (NP), which is antigenically highly conserved among multiple lineages/clades of CCHFVs and investigated its utility in an enzyme-linked immunosorbent assay (ELISA) to detect CCHFV-specific antibodies. The NP gene was cloned into the pCAGGS mammalian expression plasmid and human embryonic kidney 293 T cells were transfected with the plasmid. The expressed NP molecule was purified from the cell lysate using cesium-chloride gradient centrifugation. Purified NP was used as the antigen for the ELISA to detect anti-CCHFV IgG. Using the CCHFV NP-based ELISA, we efficiently detected CCHFV-specific IgG in anti-NP rabbit antiserum and CCHFV-infected monkey serum. When compared to the commercially available Blackbox CCHFV IgG ELISA kit, our assay showed equivalent performance in detecting CCHFV-specific IgG in human sera. These results demonstrate the usefulness of our CCHFV NP-based ELISA for seroepidemiological studies.

Crimean-Congo Hemorrhagic Fever Virus Past Infections Are Associated with Two Innate Immune Response Candidate Genes in Dromedaries.

Dromedaries are an important livestock, used as beasts of burden and for meat and milk production. However, they can act as an intermediate source or vector for transmitting zoonotic viruses to humans, such as the Middle East respiratory syndrome coronavirus (MERS-CoV) or Crimean-Congo hemorrhagic fever virus (CCHFV). After several outbreaks of CCHFV in the Arabian Peninsula, recent studies have demonstrated that CCHFV is endemic in dromedaries and camel ticks in the United Arab Emirates (UAE). There is no apparent disease in dromedaries after the bite of infected ticks; in contrast, fever, myalgia, lymphadenopathy, and petechial hemorrhaging are common symptoms in humans, with a case fatality ratio of up to 40%. We used the in-solution hybridization capture of 100 annotated immune genes to genotype 121 dromedaries from the UAE tested for seropositivity to CCHFV. Through univariate linear regression analysis, we identified two candidate genes belonging to the innate immune system: FCAR and CLEC2B. These genes have important functions in the host defense against viral infections and in stimulating natural killer cells, respectively. This study opens doors for future research into immune defense mechanisms in an enzootic host against an important zoonotic disease.

Investigation of NEAT1, IFNG-AS1, and NRIR expression in Crimean-Congo hemorrhagic fever.

Crimean-Congo hemorrhagic fever (CCHF), whose causative agent is CCHF orthonairovirus (CCHFV), demonstrates different symptoms in patients. Long noncoding RNAs (lncRNAs) take part in various pathological processes of viral diseases. They are prominent regulators of antiviral immune responses. To our knowledge, this study is the first study to investigate nuclear paraspeckle assembly transcript 1 (NEAT1), interferon (IFN) gamma antisense RNA 1 (IFNG-AS1), and negative regulator of IFN response (NRIR) expression in CCHF in the literature. We selected these lncRNAs because they are related to IFN signal or IFN-stimulated genes. We investigated NEAT1, IFNG-AS1, and NRIR gene expression in patients with CCHF. Total RNA was extracted from blood samples of 100 volunteers and NEAT1, IFNG-AS1, and NRIR expression were measured using a quantitative real-time polymerase chain reaction. NRIR expression was statistically significant in cases versus controls (p < .001), fatals versus controls (p < .001), and fatals versus nonfatals (p = .01). Furthermore, NRIR was found statistically significant at some clinical parameters including alanine aminotransferase (p = .03), international normalized ratio (p = .03), prothrombin time (p = .02), and active partial thromboplastin time (p = .01) in CCHF cases. NEAT1 and IFNG-AS1 expression were downregulated in the case and fatal groups which were compared with controls. Our results demonstrate that NRIR may be important in CCHF pathogenesis and the target of CCHF treatment.

Characterization of a novel STAT 2 knock-out hamster model of Crimean-Congo hemorrhagic fever virus pathogenesis.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne pathogen causing a febrile illness in humans, which can progress to hemorrhagic manifestations, multi-organ failure, and death. Current mouse models of CCHFV infection reliably succumb to virus challenge but vary in their ability to reflect signs of disease similar to humans. In this study, we established a signal transducer and activator of transcription 2 (STAT2) knockout hamster model to expand the repertoire of animal models of CCHFV pathogenesis that can be used for therapeutic development. These hamsters demonstrated a systemic and lethal disease in response to infection. Hallmarks of human disease were observed including petechial rash, blood coagulation dysfunction, and various biochemistry and blood cell count abnormalities. Furthermore, we also demonstrated the utility of this model for anti-CCHFV therapeutic evaluation. The STAT2 knock-out hamster model of CCHFV infection may provide some further insights into clinical disease, viral pathogenesis, and pave the way for testing of potential drug and vaccine candidates.

Dual RNA-Seq characterization of host and pathogen gene expression in liver cells infected with Crimean-Congo Hemorrhagic Fever Virus.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a tick-borne virus that can cause a hemorrhagic fever in humans, with a case fatality rate of up to 40%. Cases of CCHFV have been reported in Africa, Asia, and southern Europe; and recently, due to the expanding range of its vector, autochthonous cases have been reported in Spain. Although it was discovered over 70 years ago, our understanding of the pathogenesis of this virus remains limited. We used RNA-Seq in two human liver cell lines (HepG2 and Huh7) infected with CCHFV (strain IbAr10200), to examine kinetic changes in host expression and viral replication simultaneously at 1 and 3 days post infection. Through this, numerous host pathways were identified that were modulated by the virus including: antiviral response and endothelial cell leakage. Notably, the genes encoding DDX60, a cytosolic component of the RIG-I signalling pathway and OAS2 were both shown to be dysregulated. Interestingly, PTPRR was induced in Huh7 cells but not HepG2 cells. This has been associated with the TLR9 signalling cascade, and polymorphisms in TLR9 have been associated with poor outcomes in patients. Additionally, we performed whole-genome sequencing on CCHFV to assess viral diversity over time, and its relationship to the host response. As a result, we have demonstrated that through next-generation mRNA deep-sequencing it is possible to not only examine mRNA gene expression, but also to examine viral quasispecies and typing of the infecting strain. This demonstrates a proof-of-principle that CCHFV specimens can be analyzed to identify both the virus and host biomarkers that may have implications for prognosis.

Crimean-Congo hemorrhagic fever virus infection triggers the upregulation of the Wnt signaling pathway inhibitor genes.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a highly pathogenic agent. Thus far, vaccines and specific antiviral therapies are not available against the threat of infection. Our knowledge regarding its pathogenesis is indeed limited, and thus, developing effective antiviral therapies is hampered. Several studies have demonstrated that the CCHFV infection has an impact on numerous signal transduction pathways. In parallel, the Wnt signaling pathway components are responsible for different important biological processes including cell fate determination, cell migration and cell polarity. Moreover, its implication among several virus infections has been proven, yet little is known in reference to which components of the Wnt pathway are being activated/inhibited as a response to the infection. Our aim was to elicit the influence of the CCHFV infection on adenocarcinomic human alveolar basal epithelial cells in vitro regarding the Wnt signaling pathway-related genes. Gene-expression changes of 92 Wnt-associated genes were examined 48 h post-infection. Furthermore, ß-catenin levels were compared in the infected and uninfected cells. Significant changes were observed in the case of 13 genes. The majority of the upregulated genes are associated with the inhibition of the Wnt/ß-catenin signaling. Additionally, infected cells expressed less ß-catenin. Our findings suggest that CCHFV blocks the Wnt/ß-catenin pathway. Our study corroborates the link between CCHFV infection and the Wnt signaling pathways. In addition, it broadens our knowledge in the CCHFV pathomechanism.

Identification of potential microRNA markers related to Crimean-Congo hemorrhagic fever disease.

Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by the arbovirus Crimean-Congo hemorrhagic fever virus (CCHFV). The CCHFV has a single-stranded RNA genome of negative sense. MicroRNAs (miRNAs) are key players in virus-host interactions and viral pathogenesis. We investigated the miRNA gene expression profiles in patients with CCHF using microarray for the first time in the world. Microarray analysis was performed using mirBase Ver 21 (Agilent Technologies, Santa Clara, CA). All statistical analyses were performed across the case-control, fatal-control, and fatal-nonfatal case groups using Genespring (Ver 3.0). Fifteen miRNAs were statistical significant in patients with CCHF compared with the controls (5 were upregulated, 10 were downregulated). Seventy-five and sixty-six miRNAs are in fatal compared with control and nonfatal case, respectively (fold change ([FC] ≥50) were statistically significant. In this study, the target genes of important miRNAs were identified and Gene Ontology analyses were performed across all groups. As a result of this study, we propose that the detection of miRNAs in patients with CCHF will allow the determination of therapeutic targets in diseases. CCHF is an important public health problem that can often be fatal. In this study, we investigated miRNA expression in case-control, fatal-control, and fatal-nonfatal case groups. Significant miRNAs associated with fatality were detected in CCHF. This study will serve as a source of data for the development of an antagomir-based therapy against CCHF using miRNAs in the future.

Factors related to fatalities and clinical progression of Crimean-Congo hemorrhagic fever patients and the effects of IL 28-B gene polymorphism.

Mortality rates of Crimean-Congo hemorrhagic fever (CCHF) vary from 5% to 80%. However, there is no clear information available about why this disease is fatal for some people while others recover. In this study, the factors related to fatalities and serious clinical progression of CCHF patients and the correlation between serious prognosis and IL 28-B gene polymorphism were investigated. The study included 107 patients with a preliminary diagnosis of CCHF, and the patients were found positive for CCHFV RNA based on polymerase chain reaction (PCR) analysis. The IL 28-B rs12979860 polymorphism was identified by PCR "restriction fragment length polymorphism" (PCR-RFLP) analysis using blood samples from the patients. In addition to the IL 28-B analysis results, a variety of data along with laboratory records obtained during the hospital stay were evaluated using statistical analysis. Of the 107 cases, nine were fatal (8.4%), while the other patients recovered and were discharged. Twenty-four patients had the CC genotype (22.43%), 64 had the CT genotype (59.81%), and 19 had the TT genotype (17.76%). Of the nine patients who died, three had the CC genotype (33.33%) and six had the CT genotype (66.67%). None of the patients who died had the TT genotype. Symptoms and findings of diarrhea, abdominal pain, hemorrhage, and rash were more common in fatal cases than in non-fatal cases. The IL 28-B rs12979860 polymorphism was not found to have a statistically significant correlation with fatality or symptoms indicating serious clinical progression in CCHF patients. As has been observed in previous studies, our study showed that leukocytosis, abdominal pain and diarrhea were more common in fatal cases.

Effects of Paraoxonase-1 variants on course of severity and mortality of Crimean-Congo hemorrhagic fever.

Crimean-Congo hemorrhagic fever (CCHF) is an acute viral hemorrhagic fever caused by Crimean Congo hemorrhagic fever virus (CCHFV). Paraoxonase-1 (PON1) is a high density lipoprotein (HDL)-binding protein which defense the body against oxidative stress. To investigate the role of the PON1 gene in CCHF, we screened the genotypes of two single nucleotide polymorphisms (Q192R [rs662] and L55M [rs854560]) in CCHF patients stratified according to course of severity and mortality by using PCR-based RFLP assay. Overall, 132 patients diagnosed as CCHF were enrolled in this study. The frequencies of the three genotypes and two alleles of Q192R and L55M polymorphisms didn't show any statistically significant differences in terms of mortality and disease severity (p > 0.05). Any statistically significant differences were not found between severe and mild and fatal and non-fatal CCHF patients according to seven composite genotypes (p > 0.05). When we analyzed the clinical characteristics of CCHF patients stratified according to PON1gene polymorphisms, any statistically significant differences were not also observed (p > 0.05). Our study showed no possible association between genotypes of PON1 gene Q192R and L55M polymorphisms and CCHF.

Analysis of codon usage bias of Crimean-Congo hemorrhagic fever virus and its adaptation to hosts.

Crimean-Congo hemorrhagic fever virus (CCHFV) is a negative-sense, single stranded RNA virus with a three-segmented genome that belongs to the genus Nairovirus within the family Bunyaviridae. CCHFV uses Hyalomma ticks as a vector to infect humans with a wide range of clinical signs, from asymptomatic to Zika-like syndrome. Despite significant progress in genomic analyses, the influences of viral relationships with different hosts on overall viral fitness, survival, and evading the host's immune systems remain unknown. To better understand the evolutionary characteristics of CCHFV, we performed a comprehensive analysis of the codon usage pattern in 179 CCHFV strains by calculating the relative synonymous codon usage (RSCU), effective number of codons (ENC), codon adaptation index (CAI), and other indicators. The results indicate that the codon usage bias of CCHFV is relatively low. Several lines of evidence support the hypothesis that a translation selection factor is shaping codon usage pattern in this virus. A correspondence analysis (CA) showed that other factors, such as base composition, aromaticity, and hydrophobicity may also be involved in shaping the codon usage pattern of CCHFV. Additionally, the results from a comparative analysis of RSCU between CCHFV and its hosts suggest that CCHFV tends to evolve codon usage patterns that are comparable to those of its hosts. Furthermore, the selection pressures from Homo sapiens, Bos taurus, and Ovis aries on the CCHFV RSCU patterns were dominant when compared with selection pressure from Hyalomma spp. vectors. Taken together, both natural selection and mutation pressure are important for shaping the codon usage pattern of CCHFV. We believe that such findings will assist researchers in understanding the evolution of CCHFV and its adaptation to its hosts.

Effect of TLR10 (2322A/G, 720A/C, and 992T/A) polymorphisms on the pathogenesis of Crimean Congo hemorrhagic fever disease.

Crimean Congo hemorrhagic fever (CCHF) is a tick-borne disease caused by the Crimean Congo hemorrhagic fever virus (CCHFV). Toll-like receptors (TLRs) are type 1 transmembrane proteins of immune cells that play a critical role in innate and adaptive immunity. The present study first time aims to investigate the relation between TLR10 gene polymorphisms (720A/C, 992T/A, and 2322A/G), severity/non-severity, fatality/non-fatality, and CCFH disease by using PCR-RFLP assay in a Turkish population. TLR10 720A/C polymorphism was determined to be statistically significant both genotype and allele frequency (P = 0,011, P = 0.015, respectively). TLR10 992T/A polymorphism was found statistically significant relationships between patient and control (P = 0.026) and individual with AA genotype have approximately three times greater risk than TT genotype (OR = 2.93). There was not a significant difference in 2322A/G genotype distribution (P = 0.152). There were also statistically significant associations between both TLR10 992T/A and 2322A/G polymorphism and patient mortality (P = 0.001 and P = 0.008, respectively). We have not found statistically any linkage among TLR10 haplotype, but individual AAA and GAT haplotype have higher risk than individual AAT haplotype (OR = 3.22, OR = 1.93, respectively). Consequently, this study shows that pathogenesis of CCHF disease is associated with the TLR10 720A/C and 992T/A polymorphisms. There is a statistically significant association in fatal/non-fatal patients with TLR10 720A/C and 992T/A. The TLR10 992AA genotype might increase and TLR10 720CC genotype might decrease susceptibility to pathogenesis of CCHF disease. TLR 10 polymorphisms may be also an important biomarker for CCHF susceptibility and fatality rate.

The possible role of CCR5Δ32 mutation in Crimean-Congo hemorrhagic fever infection.

Crimean-Congo hemorrhagic fever infection (CCHF) is a viral zoonosis. The pathogenesis of this disease has not been established so far, however, cytokines account for its progression and outcome. The aim of the present study is to investigate the association between chemokine receptor 5 (CCR5) gene Δ32 mutation and pathogenity, severity, and mortality of CCHF. This case-control study included 133 CCHF patients diagnosed by detection of CCHV RNA positivity and 97 healthy control subjects. CCR5 gene Δ32 mutation analyzed by polymerase chain reaction (PCR) method. The results were compared by using SPSS 16.0 and WINPEPI software's. The genotype distribution and allele frequency of the CCR5Δ32 were statistically different between the patients and the control group (P = 0.017; OR: 4.98 95% CI = 1.65-14.99 and P = 0.019; OR:4.76 95%CI = 1.30-17.50, respectively). CCR5/CCR5 (W/W) genotype and W allele of CCR5 gene were more common in patient group than in controls. There was no significant difference in severe and mild cases with regard to genotype distribution and allele distribution of CCR5Δ32 mutation (P >0.05). These results suggest that the CCR5 gene and its product might play a role in the pathogenesis of CCHF disease. Future studies will help us to uncover the exact role of CCR5 in the pathogenesis and prognosis of CCHF and to treat the disease.

Apoptosis-Related Gene Expression in an Adult Cohort with Crimean-Congo Hemorrhagic Fever.

Crimean-Congo Hemorrhagic Fever (CCHF) is a life threatening acute viral infection characterized by fever, bleeding, leukopenia and thrombocytopenia. It is a major emerging infectious diseases threat, but its pathogenesis remains poorly understood and few data exist for the role of apoptosis in acute infection. We aimed to assess apoptotic gene expression in leukocytes in a cross-sectional cohort study of adults with CCHF. Twenty participants with CCHF and 10 healthy controls were recruited at a tertiary CCHF unit in Turkey; at admission baseline blood tests were collected and total RNA was isolated. The RealTime ready Human Apoptosis Panel was used for real-time PCR, detecting differences in gene expression. Participants had CCHF severity grading scores (SGS) with low risk score (10 out of 20) and intermediate or high risk scores (10 out of 20) for mortality. Five of 20 participants had a fatal outcome. Gene expression analysis showed modulation of pro-apoptotic and anti-apoptotic genes that facilitate apoptosis in the CCHF patient group. Dominant extrinsic pathway activation, mostly related with TNF family members was observed. Severe and fatal cases suggest additional intrinsic pathway activation. The clinical significance of relative gene expression is not clear, and larger longitudinal studies with simultaneous measurement of host and viral factors are recommended.

Is there any relationship between Toll-like receptor 3 c.1377C/T and -7C/A polymorphisms and susceptibility to Crimean Congo hemorrhagic fever?

Crimean-Congo hemorrhagic fever (CCHF) is an infectious disease that is caused by CCHF virus. A family of transmembrane receptors called as Toll-like receptors (TLRs) selectively acts in recognizing a wide range of microbial components and endogenous molecules released by damaged tissue and have been preserved throughout evolution. TLRs initiate some signaling cascades which activate the innate immune system. Mainly four TLRs act in protection against viral infections; TLR3 is one of them. TLR3 identifies dsRNA. By producing inflammatory cytokines and type I interferons, it generates an antiviral immune response. Proper response to TLR ligands may be impaired by single nucleotide polymorphisms (SNPs) within TLR genes in some indviduals, and this can cause varied susceptibility to infections. In the present work, polymerase chain reaction-based restriction fragment length polymorphism is used to analyze the frequencies of TLR3 (c.1377C/T and -7C/A) polymorphisms in 149 CCHF patients and 171 healthy adults as controls, in Cumhuriyet University, Sivas/Turkey. We also investigated the relation between these polymorphisms and severity or mortality of CCHF disease. This is the first study investigating the TLR3 SNPs in patients with CCHF. In the present study, the frequency of the TLR3 (c.1377C/T and -7A/C) genotypes in fatal and non-fatal cases were comparable, however, the homozygous mutant (TT) genotype frequency of TLR3 c.1377C/T in CCHF patients was significantly higher than that of the healthy controls. In conclusion, presence of TLR3 c.1377 TT genotype may have a role in the susceptibility to CCHF. J. Med. Virol. 88:1690-1696, 2016. © 2016 Wiley Periodicals, Inc.