Exposure to Cadmium Telluride Quantum Dots and Gene Expression Profile of Huh-7 Hepatocellular Carcinoma Cell Line.

Nanoparticles have shown promising potential for efficient drug delivery, circumventing biological interferences like immunological and renal clearance and mechanical and enzymatic destruction. However, a handful of research papers have questioned the biomedical use of metal-based nanoparticles like cadmium telluride quantum dots (CdTe-QDs) for their cytotoxic, genotoxic, and carcinogenic potential. Herein, we examined the effects of CdTe-QD NPs on gene expression profile of hepatocellular carcinoma (Huh-7) cell line. Huh-7 cells were treated with CdTe-QD NPs (10 µg/ml for 6, 12, and 24 hours, and 25 µg/ml for 6 and 12 hours), and transcriptomic analysis was performed using microarray to evaluate the global gene expression profile. Differential expressed genes (DEGs) were observed for both the doses (10 and 25 µg/ml) of CdTe-QD NPs at different time points. Gene ontology (GO) analysis revealed that genes involved in molecular function of cell cycle, organizational injury and abnormalities, cell death and survival, gene expression, cancer, organismal survival, and cellular development were differentially expressed. Overall, we have demonstrated differential expression of several genes, involved in maintaining cell survival, metabolism, and genome integrity. These findings were confirmed by RT-qPCR study for some canonical pathway genes signifying possible implication in NP toxicity-mediated cell survival and inhibition of cell death.

Association between interleukin-27 gene polymorphisms and Plasmodium falciparum Malaria.

Malaria is often characterized by a complicated disease course due to multifaceted intrinsic genetic factors of the host and the parasite. This study aimed to investigate the role of interleukin-27 (IL-27) gene polymorphisms in Plasmodium falciparum malaria infection in a Saudi Arabian cohort. This case-control study obtained blood samples from 250 malaria patients with P. falciparum and 200 randomly identified healthy control subjects from the Malaria Center in the Jazan area. Malaria patients were grouped into three cohorts as follow: low (<500 parasites/µl of blood), moderate (500-1000 parasites/µl of blood), and high (>1000 parasites/µl of blood) parasitemia. The results show that the IL-27 variant rs181209 was significantly associated with malaria patients (P = 0.026). Similarly, the homozygous GG genotype of rs26528 was also associated with risk of developing P. falciparum malaria (P = 0.032). The minor allele C of variant rs181206 exhibited an association with low to moderate parasitemia (P = 0.046). Furthermore, the rs181209 AA genotype was statistically significant in age group 1-5 years (P = 0.049). In conclusion, this study suggests that variant rs181209 and rs26528 could be associated with the risk of malaria infection by P. falciparum in the population studied.

Genetic Analysis, Population Structure, and Characterisation of Multidrug-Resistant Klebsiella pneumoniae from the Al-Hofuf Region of Saudi Arabia.

Multidrug-resistant Klebsiella pneumoniae (MDR-KP) is a major public health problem that is globally associated with disease outbreaks and high mortality rates. As the world seeks solutions to such pathogens, global and regional surveillance is required. The aim of the present study was to examine the antimicrobial susceptibility pattern and clonal relatedness of Klebsiella pneumoniae isolates collected for a period of three years through pulse field gel electrophoresis (PFGE). Isolate IDs, antimicrobial assays, ESBL-production, and minimum inhibitory concentrations (MICs) were examined with the Vitek 2 Compact Automated System. IDs were confirmed by 16S rRNA gene sequencing, with the resulting sequences being deposited in NCBI databases. DNA was extracted and resistance genes were detected by PCR amplification with appropriate primers. Isolates were extensive (31%) and multidrug-resistant (65%). Pulsotype clusters grouped the isolates into 22 band profiles that showed no specific pattern with phenotypes. Of the isolates, 98% were ESBL-KP, 69% were carbapenem-resistant Enterobacteriaceae (CRE) strains, and 72.5% comprised the carriage of two MBLs (SIM and IMP). Integrons (ISAba1, ISAba2, and IS18) were detected in 69% of the MDR-KP. Additionally, OXA-23 was detected in 67% of the isolates. This study therefore demonstrates clonal diversity among clinical K. pneumoniae, confirming that this bacterium has access to an enormous pool of genes that confer high resistance-developing potential.

Associations of Single Nucleotide Polymorphisms in IL-18 Gene with Plasmodium falciparum-Associated Malaria.

INTRODUCTION: Interleukin-18 (IL-18) is a pro-inflammatory cytokine, reported to be involved in the initial immune responses against malaria. Genetic variations in the host are an important factor that influences the etiology of malaria at several disease levels. Polymorphisms within the IL-18 gene are associated with susceptibility and clinical outcome of several diseases. METHODS: We genotyped single nucleotide polymorphisms (SNPs) in IL-18 of patients infected with Plasmodium falciparum with varying extent of parasitemia and different age groups. RESULTS: SNPs rs5744292 (OR = 70.446; 95% CI = 4.318-1149.323; p<0.0001) and rs544354 (OR = 1.498; 95% CI = 1.088-2.063; p=0.013) were found to be significantly associated with parasitemia in P. falciparum-infected patients when compared with healthy control subjects. SNP rs5744292 (OR = 7.597; 95% CI=1.028-56.156; p=0.019) was associated with increased parasite density in infected patients. SNPs rs544354 (OR 0.407; 95% CI=0.204-0.812; p = 0.009) and rs360714 (OR of 0.256; 95% CI=0.119-0.554; p = 0.001) were significantly associated with parasite density in an age-dependent manner, with the risk alleles present more frequently among the younger (1-9 years) patients. Several haplotypes were found to have a significant association with parasitemia. In-vitro expression analysis using luciferase reporter assay showed that SNPs rs1946518 and rs187238 in the IL-18 gene promoter region and rs360728 and rs5744292 in the 3'-untranslated region of the IL-18 gene were associated with enhanced transcriptional activity. CONCLUSION: Our results suggest that polymorphisms within the IL-18 gene are associated with the susceptibility to P. falciparum infection and related parasitemia among groups with different parasite density and across various age groups.

Gene Expression and Transcriptome Profiling of Changes in a Cancer Cell Line Post-Exposure to Cadmium Telluride Quantum Dots: Possible Implications in Oncogenesis.

Cadmium telluride quantum dots (CdTe-QDs) are acquiring great interest in terms of their applications in biomedical sciences. Despite earlier sporadic studies on possible oncogenic roles and anticancer properties of CdTe-QDs, there is limited information regarding the oncogenic potential of CdTe-QDs in cancer progression. Here, we investigated the oncogenic effects of CdTe-QDs on the gene expression profiles of Chang cancer cells. Chang cancer cells were treated with 2 different doses of CdTe-QDs (10 and 25 µg/ml) at different time intervals (6, 12, and 24 h). Functional annotations helped identify the gene expression profile in terms of its biological process, canonical pathways, and gene interaction networks activated. It was found that the gene expression profiles varied in a time and dose-dependent manner. Validation of transcriptional changes of several genes through quantitative PCR showed that several genes upregulated by CdTe-QD exposure were somewhat linked with oncogenesis. CdTe-QD-triggered functional pathways that appear to associate with gene expression, cell proliferation, migration, adhesion, cell-cycle progression, signal transduction, and metabolism. Overall, CdTe-QD exposure led to changes in the gene expression profiles of the Chang cancer cells, highlighting that this nanoparticle can further drive oncogenesis and cancer progression, a finding that indicates the merit of immediate in vivo investigation.

Association of polymorphisms in genes involved in enamel formation, taste preference and immune response with early childhood caries in Saudi pre-school children.

Dental caries is primarily elicited by modifiable factors such as inadequate oral hygiene, poor dietary practices and deficient fluoride exposure. However, there is a growing body of evidence suggesting the profound influence of genetic factors in dental caries susceptibility. The present study aimed to evaluate the association between single nucleotide polymorphisms (SNPs) in ENAM (rs12640848), MMP20 (rs1784418), TAS2R38 (rs713598), and LTF (rs4547741) genes and early childhood caries (ECC) in Saudi preschool children. This case-control study enrolled 360 Saudi preschool children (262 with ECC and 98 caries-free). Data on environmental factors were collected through a questionnaire. However, caries experience and oral hygiene data were obtained during clinical examination. Buccal swab samples were collected for DNA extraction and SNPs were genotyped using PCR and DNA sequencing. Children with ECC were compared to caries free children (control), then they were categorized into two categories based on ECC severity as follows; non-severe ECC (NS-ECC), and severe-ECC (S-ECC). Association between the SNPs, ECC, NS-ECC, and S-ECC was reported as an odds ratio (OR) with a 95% confidence interval (CI). The majority of the children (72.8%) exhibited ECC (31.7% NS-ECC and 41.1% S-ECC) with mean dmft of 4.20 ± 4.05. Multivariate analyses of environmental factors showed that nocturnal feeding was a risk factor for ECC (P = 0.008). Poor oral hygiene was also a risk factor for both NS-ECC and S-ECC (ECC: P < 0.0001, NS-ECC: P = 0.032 and S-ECC: P < 0.0001). Univariate analysis showed that the AG genotype of rs1784418 of MMP20 gene was protective against ECC (OR = 0.532; 95% CI = 0.316-0.897, P = 0.018) and against NS-ECC (OR = 0.436; 95% CI = 0.238-0.798, P = 0.007). When environmental risk factors for ECC were included as covariates during multivariate analysis, AG variant in rs1784418 of MMP20 gene remained less frequent in NS-ECC cases compared to controls with borderline significance (OR = 0.542; 95% CI = 0.285-1.033, P = 0.063). Our findings concluded that MMP20 rs1784418 SNP might be associated with protection against ECC in Saudi preschool children.

Potential anti-inflammatory and anti-apoptotic effect of Coccinia grandis plant extract in LPS stimulated-THP-1 cells.

Coccinia grandis (C. grandis) L is an Indian medicinal plant from the Cucurbitaceae family whose extracts possess anti-oxidant, anti-infective, and anti-inflammatory properties. The objective of the present study was to probe the potential immunomodulatory of C. grandis crude extract on different pathways in THP-1 cells as probed by changes in expression of several proteins. THP-1 cells were differentiated into macrophages after treatment with phorbol-12-myristate 13-acetate, followed by exposure to lipopolysaccharide (LPS) with or without 50 or 100 µg/ml of C. grandis extract. Treatment of the cells with the extract significantly downregulated the expression and release of pro-inflammatory cytokines (IL-6, IL-1ß, CCL2, CCL22, CXCL10/IP-10, CX3CL1 and CXCL8/IL-8), proteins (ERK5, BAX, BCL2, Cyclin D, ERK1, NF-κB, P-IκBα,P- NF-κB and P-p38) and molecular signaling pathways (NF-κB, p38 MAPK, ERK1/2 and IL-6/JAK/STAT3 signaling cascades). This study is the first to highlight the ability of C. grandis extract to modulate several pathways, including proliferation, the expression of inflammatory cytokines, phagocytosis, migration properties and apoptosis, in human monocytic THP-1 cells.

Interleukin-22 Polymorphisms in Plasmodium falciparum-Infected Malaria Patients.

Background and Objectives. Malaria infection, caused by Plasmodium falciparum, is the most lethal and frequently culminates in severe clinical complications. Interleukin-22 (IL-22) has been implicated in several diseases including malaria. The objective of this study was to investigate the role of IL-22 gene polymorphisms in P. falciparum infection. Material and Methods. Ten single-nucleotide polymorphisms (SNPs), rs976748, rs1179246, rs2046068, rs1182844, rs2227508, rs2227513, rs2227478, rs2227481, rs2227491, and rs2227483, of IL-22 gene were genotyped through PCR-based assays of 250 P. falciparum infection. IL-22 gene promoter activity. RESULTS: We found that the rs2227481 TT genotype (odds ratio 0.254, confidence interval = 0.097-0.663, P. P. falciparum infection. P. P. P. P. CONCLUSION: The study suggests that IL-22 polymorphisms in rs2227481 and rs2227483 could contribute to protection against P. falciparum infection. IL-22 gene promoter activity.

Molecular epidemiology, phylogenetic analysis and genotype distribution of hepatitis B virus in Saudi Arabia: Predominance of genotype D1.

Despite the implementation of various vaccination programs, hepatitis B virus (HBV) poses a considerable health problem in Saudi Arabia. Insight on HBV evolutionary history in the region is limited. We performed a comprehensive epidemiological and phylogenetic reconstruction based on a large cohort of HBV infected patients. Three hundred and nineteen HBV-infected patients with different clinical manifestations, including inactive and active chronic carriers and patients with cirrhosis and hepatocellular carcinoma (HCC), were enrolled in this study. The full-length large S gene was amplified and sequenced. Phylogenetic analysis was performed to determine the genotype and subgenotypes of the isolates. Phylogenetic tree analysis revealed that genotype D is the most dominant genotype among patients. Moreover, this analysis identified two strains with genotype E isolated from active carriers. Detailed phylogenetic analyses confirmed the presence of four HBV D subgenotypes, D1 (93%, n = 296), D2 (0.02%, n = 5), D3 (0.003%, n = 1), and D4 (0.003%, n = 1). In addition, six genotype D strains were not assigned to any existing HBV D subgenotype. The large S gene of eight strains showed signatures of genotype recombination between the genotypes D and A and between D and E. Several strains harbored medically important point mutations at the protein level. Along with the dominance of the HBV genotype D, isolation of the E genotype and several recombinant strains from patients with Saudi Arabian origin is an essential result for decisions involving therapeutic measures for patients. Development of vaccines and detection of diagnostic escape mutations at antigenic epitopes on the HBsAg will be valuable to public health authorities. Furthermore, the diversity at the nucleotide and amino acid levels and different proportions of dN/dS at the PreS1, PreS2, and HBsAg reveal the selective pressure trend from inactive status towards advanced liver diseases.

In Vitro Studies on the Immunomodulatory Effects of Pulicaria crispa Extract on Human THP-1 Monocytes.

BACKGROUND: Pulicaria crispa (P. crispa) is a plant from the Compositae family that exhibits antioxidant, anti-inflammatory, antibacterial, and cytotoxic activities. OBJECTIVE: The current study aimed at investigating the immunomodulatory effects of P. crispa extract in lipopolysaccharide- (LPS-) stimulated human monocytic THP-1 cells. METHODS: To induce macrophage differentiation, THP-1 cell lines were treated with phorbol-12-myristate 13-acetate, followed by exposure to LPS with or without 50 or 100 µg/ml of P. crispa extract. The following tests were employed to test the immunomodulatory effects of the extract: MTT assay, ELISA, Western blotting analysis, cell migration and phagocytosis assays, and Annexin V staining method. RESULTS: Exposure to 100 µg/ml P. crispa extract significantly reduced THP-1 cell proliferation, migration, and phagocytosis (in LPS-stimulated cells, but not in unstimulated cells). Moreover, the extract alone significantly reduced the rate of THP-1 cell apoptosis, while it increased the rate of late apoptosis. Molecular investigations showed that treatment with P. crispa extract significantly upregulated the expression of ERK1, p-MAPK, P-P38, and Bcl2, while it significantly reduced the expression of ERK5, Bax, NF-κB, P-NF-κB, CCL1, CCL2, CCL5, CCL22, CXCL1, and CXCL10. CONCLUSION: Pulicaria crispa extract exhibited anti-inflammatory, antiproliferative, antimigratory, and antiphagocytic effects in LPS-stimulated THP-1 cells. Future studies should investigate these mechanisms in animal models with chronic inflammatory diseases.

Genetic variations of NOD2 and MD2 genes in hepatitis B virus infection.

OBJECTIVES: Nucleotide oligomerization domain 2 (NOD2) and myeloid differentiation protein 2 (MD-2) have crucial roles in the innate immune system. NOD2 is a member of the NOD-like receptor (NLR) family of pattern recognition receptors (PRRs), while MD-2 is a co-receptor for Toll-like receptor 4 (TLR4), which comprises another group of PRRs. Genetic variations in the NOD2 and MD-2 genes may be susceptibility factors to viral pathogens including hepatitis B virus (HBV). We investigated whether polymorphisms at NOD2 (rs2066845 and rs2066844) or at MD-2 (rs6472812 and rs11466004) were associated with susceptibility to HBV infection and advancement to related liver complications in a Saudi Arabian population. Methods: A total of 786 HBV-infected patients and 600 healthy uninfected controls were analyzed in the present study. HBV-infected patients were categorized into three groups based on the clinical stage of the infection: inactive HBV carriers, active HBV carriers, and patients with liver cirrhosis + hepatocellular carcinoma (HCC). Results: All four SNPs were significantly associated with susceptibility to HBV infection although none of the SNPs tested in NOD2 and MD-2 were significantly associated with persistence of HBV infection. We found that HBV-infected patients that were homozygous CC for rs2066845 in the NOD2 gene were at a significantly increased risk of progression to HBV-related liver complications (Odds Ratio = 7.443 and P = 0.044). Furthermore, haplotype analysis found that the rs2066844-rs2066845 C-G and T-G haplotypes at the NOD2 gene and four rs6472812-rs11466004 haplotypes (G-C, G-T, A-C, and A-T) at the MD-2 gene were significantly associated with HBV infection in the affected cohort compared to those found in our control group. Conclusion: We found that the single nucleotide polymorphisms rs2066844 and rs2066845 at NOD2 and rs6472812 and rs11466004 at MD-2 were associated with susceptibility to HBV infection in a Saudi population.

Association between IL-37 gene polymorphisms and risk of HBV-related liver disease in a Saudi Arabian population.

Interleukin-37 (IL-37) has recently been recognized as a strong anti-inflammatory cytokine having anti-tumor activity against hepatocellular carcinoma (HCC) in hepatitis B virus (HBV)-infected patients. HCC is a typical inflammation-related cancer, and genetic variations within the IL-37 gene may be associated with the risk of HBV infection. Identification of the allelic patterns that genetically have a high disease risk is essential for the development of preventive diagnostics for HBV-mediated liver disease pathogenesis. In this study, we aimed to investigate the association between single nucleotide polymorphisms (SNPs) within the IL-37 gene and disease sequelae associated with HBV infection. We genotyped ten IL-37 SNPs in 1274 patients infected with HBV and 599 healthy controls from a Saudi Arabian population. Among the selected SNPs, two SNPs (rs2723175 and rs2708973) were strongly associated with HBV infection, and six SNPs (rs2723176, rs2723175, rs2723186, rs364030, rs28947200, rs4392270) were associated with HBV clearance, comparing healthy controls and HBV infected-patients respectively. A suggestive association of rs4849133 was identified with active HBV surface antigen (HBsAg) carrier and HBV-related liver disease progression. In conclusion, our findings suggest that variations at the IL-37 gene may be useful as genetic predictive risk factors for HBV infection and HBV-mediated liver disease progression in the Saudi Arabian population.

The Correlation Between Hepatitis B Virus Precore/Core Mutations and the Progression of Severe Liver Disease.

Viral mutations acquired during the course of chronic hepatitis B virus (HBV) infection are known to be associated with the progression and severity of HBV-related liver disease. This study of HBV-infected Saudi Arabian patients aimed to identify amino acid substitutions within the precore/core (preC/C) region of HBV, and investigate their impact on disease progression toward hepatocellular carcinoma (HCC). Patients were categorized according to the severity of their disease, and were divided into the following groups: inactive HBV carriers, active HBV carriers, liver cirrhosis patients, and HCC patients. Two precore mutations, W28* and G29D, and six core mutations, F24Y, E64D, E77Q, A80I/T/V, L116I, and E180A were significantly associated with the development of cirrhosis and HCC. Six of the seven significant core mutations that were identified in this study were located within immuno-active epitopes; E77Q, A80I/T/V, and L116I were located within B-cell epitopes, and F24Y, E64D, and V91S/T were located within T-cell epitopes. Multivariate risk analysis confirmed that the core mutations A80V and L116I were both independent predictors of HBV-associated liver disease progression. In conclusion, our data show that mutations within the preC/C region, particularly within the immuno-active epitopes, may contribute to the severity of liver disease in patients with chronic hepatitis. Furthermore, we have identified several distinct preC/C mutations within the study population that affect the clinical manifestation and progression of HBV-related disease. The specific identity of HBV mutations that are associated with severe disease varies between different ethnic populations, and so the specific preC/C mutations identified here will be useful for predicting clinical outcomes and identifying the HBV-infected patients within the Saudi population that are at high risk of developing HCC.

Deletion and Functional Analysis of Hepatitis B Virus X Protein: Evidence for an Effect on Cell Cycle Regulators.

BACKGROUND/AIMS: The hepatitis B virus X protein (HBx) is a viral trans-activator that plays a crucial role in pathogenesis of hepatocellular carcinoma (HCC) via an unknown mechanism. The role of HBx in modulating cell proliferation and programmed cell death is replete with controversies. Thus, the goal of this study was to elucidate the effect of HBx and its deletion mutants on cell cycle progression in human hepatoma cells. METHODS: Huh7 cells transfected with either full-length or truncated HBx were tested for their mitogenic potential based on their effect on the expression of key cell cycle-related proteins (p27, cyclin D1, p21, and p53) and pro-apoptotic proteins such as cleaved poly (ADP-ribose) polymerase (PARP) and Bax. Western blotting and immunofluorescence techniques were applied to detect changes in the expression levels and intracellular localization, respectively, of the investigated proteins. Also, Quantitative real-time PCR (qRT-PCR) was used to detect changes in RNA levels. RESULTS: An increased anchorage-independent growth of cells transfected with HBx-WT and its deletion mutants was observed. The cell cycle regulatory molecules were differentially modulated by full-length HBx (1-154) and its different N- and C-terminal truncated forms (HBx (31-154), HBx (61-154), HBx (1-94), and HBx (61-124)). An enhanced modulation of p27, p21, and cyclin D1 was associated with HBx (1-154), whereas p53 expression was significantly inhibited by HBx (61-124). Similarly, the expression of cleaved PARP and Bax was efficiently suppressed by HBx (1-94) and HBx (61-154). CONCLUSION: The HBx-WT and its mutants play a critical role in the pathogenesis and progression of HCC by modulating cell cycle regulatory proteins.

Hepatitis B virus (HBV) X gene mutations and their association with liver disease progression in HBV-infected patients.

Hepatitis B virus (HBV) is one of the most widespread human pathogens causing chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC). This study investigated the clinical impact of single and combinational mutations in HBx gene on the pathogenesis of HCC during progressive stages of liver disease. The patients were categorized into inactive HBV carriers, active carriers, cirrhosis and HCC groups based on disease severity. Male sex, age > 50 years, and high serum alanine aminotransferase level were associated with risk of progressive liver disease. I127T, V131I, and F132Y/I/R mutations showed a significant increasing trend associated with the disease progression to HCC. H94Y and K130M mutations were also significantly associated with severe liver disease. One double mutation (K130M+V131I) and two triple mutations (I127T+K130M+V131L and K130M+V131I+F132Y) were observed, with significant rising prevalence through progressive clinical phases of liver disease to HCC. Several single and combinational mutations in HBx correlating with severity and progressive clinical phases of HBV infection were identified. The mutational combinations may have a synergistic effect in accelerating the progression to HCC. These specific patterns of HBx mutations can be useful in predicting the clinical outcome of HBV-infected patients and may serve as early markers of high risk of developing HCC.

The epidemic dynamics of hepatitis C virus subtypes 4a and 4d in Saudi Arabia.

The relatedness between viral variants sampled at different locations through time can provide information pertinent to public health that cannot readily be obtained through standard surveillance methods. Here, we use virus genetic data to identify the transmission dynamics that drive the hepatitis C virus subtypes 4a (HCV4a) and 4d (HCV4d) epidemics in Saudi Arabia. We use a comprehensive dataset of newly generated and publicly available sequence data to infer the HCV4a and HCV4d evolutionary histories in a Bayesian statistical framework. We also introduce a novel analytical method for an objective assessment of the migration intensity between locations. We find that international host mobility patterns dominate over within country spread in shaping the Saudi Arabia HCV4a epidemic, while this may be different for the HCV4d epidemic. This indicates that the subtypes 4a and 4d burden can be most effectively reduced by combining the prioritized screening and treatment of Egyptian immigrants with domestic prevention campaigns. Our results highlight that the joint investigation of evolutionary and epidemiological processes can provide valuable public health information, even in the absence of extensive metadata information.

Middle east respiratory syndrome corona virus spike glycoprotein suppresses macrophage responses via DPP4-mediated induction of IRAK-M and PPARγ.

Middle East Respiratory Syndrome Corona Virus (MERS-CoV) is transmitted via the respiratory tract and causes severe Acute Respiratory Distress Syndrome by infecting lung epithelial cells and macrophages. Macrophages can readily recognize the virus and eliminate it. MERS-CoV infects cells via its Spike (S) glycoprotein that binds on Dipeptidyl-Peptidase 4 (DPP4) receptor present on macrophages. Whether this Spike/DPP4 association affects macrophage responses remains unknown. Herein we demonstrated that infection of macrophages with lentiviral particles pseudotyped with MERS-CoV S glycoprotein results in suppression of macrophage responses since it reduced the capacity of macrophages to produce TNFα and IL-6 in naive and LPS-activated THP-1 macrophages and augmented LPS-induced production of the immunosuppressive cytokine IL-10. MERS-CoV S glycoprotein induced the expression of the negative regulator of TLR signaling IRAK-M as well as of the transcriptional repressor PPARγ. Inhibition of DPP4 by its inhibitor sitagliptin or siRNA abrogated the effects of MERS-CoV S glycoprotein on IRAK-M, PPARγ and IL-10, confirming that its immunosuppressive effects were mediated by DPP4 receptor. The effect was observed both in THP-1 macrophages and human primary peripheral blood monocytes. These findings support a DPP4-mediated suppressive action of MERS-CoV in macrophages and suggest a potential target for effective elimination of its pathogenicity.

Association of Toll-Like Receptor 3 Single-Nucleotide Polymorphisms and Hepatitis C Virus Infection.

Toll-like receptor 3 (TLR3) plays a key role in innate immunity by recognizing pathogenic, double-stranded RNAs. Thus, activation of TLR3 is a major factor in antiviral defense and tumor eradication. Although downregulation of TLR3 gene expression has been mainly reported in patients infected with hepatitis C virus (HCV), the influence of TLR3 genotype on the risk of HCV infection, HCV-related cirrhosis, and/or hepatocellular carcinoma (HCC) remains to be determined. Single-nucleotide polymorphisms (SNPs) within the TLR3 gene and their associations with HCV-related disease risk were investigated in a Saudi Arabian population in this study. Eight TLR3 SNPs were analyzed in 563 patients with HCV, which consisted of 437 patients with chronic HCV infections, 88 with HCV-induced liver cirrhosis, and 38 with HCC. A total of 599 healthy control subjects were recruited to the study. Among the eight TLR3 SNPs studied, the rs78726532 SNP was strongly associated with HCV infection when compared to that in healthy control subjects. The rs5743314 was also strongly associated with HCV-related liver disease progression (cirrhosis and HCC). In summary, these results indicate that distinct genetic variants of TLR3 SNPs are associated with HCV infection and HCV-mediated liver disease progression in the Saudi Arabian population.

PARK2 polymorphisms predict disease progression in patients infected with hepatitis C virus.

 Background. The protein encoded by PARK2 gene is a component of the ubiquitin-proteasome system that mediates targeting of proteins for the degradation pathway. Genetic variations at PARK2 gene were linked to various diseases including leprosy, typhoid and cancer. The present study investigated the association of single nucleotide polymorphisms (SNPs) in the PARK2 gene with the development of hepatitis C virus (HCV) infection and its progression to severe liver diseases. MATERIAL AND METHODS: A total of 800 subjects, including 400 normal healthy subjects and 400 HCV-infected patients, were analyzed in this study. The patients were classified as chronic HCV patients (group I), patients with cirrhosis (group II) and patients with hepatocellular carcinoma (HCC) in the context of cirrhosis (group III). DNA was extracted and was genotyped for the SNPs rs10945859, rs2803085, rs2276201 and rs1931223. RESULTS: Among these SNPs, CT genotype of rs10945859 was found to have a significant association towards the clinical progression of chronic HCV infection to cirrhosis alone (OR = 1.850; 95% C. I. 1.115-3.069; p = 0.016) or cirrhosis and HCC (OR = 1.768; 95% C. I. 1.090-2.867; p value = 0.020). CONCLUSION: SNP rs10945859 in the PARK2 gene could prove useful in predicting the clinical outcome in HCV-infected patients.

Zika virus: a new pandemic threat.

Zika virus (ZIKV) is an emerging arbovirus of the Flaviviridae family and is related to dengue, Chikungunya, West Nile, yellow fever, and Japanese encephalitis viruses. ZIKV was first discovered in Uganda in 1947. Different species of mosquito from the Aedes genus, mainly A. aegypti and A. albopictus are the vectors responsible for ZIKV infection in humans. It is also reported that ZIKV is transmitted congenitally, sexually, and through blood donation. Until recently, ZIKV outbreaks were sporadic and self-limiting. The first large epidemic was reported from Yap Island in 2007 followed by an outbreak of Zika fever in French Polynesia in 2013. Brazil is the epicenter of the current ZIKV epidemic which is rapidly spreading across the Americas. ZIKV infection remained relatively less studied in view of its low case numbers, and low clinical impact relative to other arboviruses. However, all this is set to change with its rapid spread in the Western hemisphere and suspected complications particularly microcephaly in newborn babies with ZIKV infected mothers. ZIKV is expected to substantially add to both short-term and long-term economic burden of the effected countries. Due to the large number of people travelling across the borders and some reported cases of transmission of ZIKV via contaminated blood, screening and identification of asymptomatic infected individuals are important.