Dengue virus (DENV) is a member of the Flaviviridae family, transmitted to human via mosquito. DENV infection is common in tropical areas and occasionally causes life-threatening symptoms. DENV contains a relatively short positive-stranded RNA genome, which encodes ten viral proteins. Thus, the viral life cycle is necessarily rely on or regulated by host factors. In silico analyses in conjunction with in vitro kinase assay were used to study kinases that potentially phosphorylate DENV NS5. Potential kinase was inhibited or activated by a specific inhibitor (or siRNA), or an activator. Results of the inhibition and activation on viral entry/replication and host cell survival were examined. Our in silico analyses indicated that the non-structural protein 5 (NS5), especially the RNA-dependent RNA polymerase (RdRp) domain, contains conserved phosphorylation sites for protein kinase C (PKC). Phosphorylation of NS5 RdRp was further verified by PKC in vitro kinase assay. Inhibitions of PKC by a PKC-specific chemical inhibitor or siRNA suppressed NS5 phosphorylation in vivo, increased viral replication and reduced viability of the DENV-infected cells. In contrary, activation of PKC effectively suppressed intracellular viral number. These results indicated that PKC may act as a restricting mechanism that modulates the DENV replication and represses the viral outburst in the host cells.

In recent years, glaucoma has been proposed as an autoimmune disease and an understanding immune-regulation concept has been applied for novel glaucoma therapy. Current evidence suggests an innate immunity is a keystone step for primary open angle glaucoma (POAG) pathogenesis resulting from trabecular meshwork (TM) cell fibrosis and retinal ganglion cell (RGC) death. Toll-like receptor 4 (TLR4) is a common player in the innate immunity, which appears on the TM and RGC of POAG. The activation of TLR4 regulates several molecules involving both fibrosis and cell death. Inhibition of TLR4 decreases TGF-β2-induced fibrosis in TM cells and enhances cell survival of RGC in both optic nerve crush and ischemia models. In this review, we will summarize the molecular mechanisms of TLR4 related to POAG pathogenesis. An understanding of this mechanism may provide novel development of therapeutic strategies for POAG.

In recent years, microbiota-associated neurodegenerative diseases have been exploited and provided new insight into disease pathogenesis. However, primary open-angle glaucoma (POAG), known as a complex neurodegenerative disease resulting from retinal ganglion cell death and optic nerve damage, can cause irreversible blindness and visual field loss. POAG, which shares several similarities with Parkinson’s disease (PD) and Alzheimer’s disease (AD), has limited studies and slow progression in the understanding of pathogenesis when compared to PD and AD. In this review, we summarized the current knowledge of POAG and commensal microbiota, combined with several lines of evidence in PD and AD to propose a possible hypothesis for POAG pathogenesis: microorganisms cause glaucoma via gut–retina axis, resulting in autoantibodies and autoreactive T cells that lead to autoimmunity. Furthermore, dual-hit hypothesis, an example of a commensal pathogen that causes PD, was partially exported in POAG. Finally, future perspectives are suggested to expand understanding of POAG.

Background: The emergence ofPlasmodium falciparumresistance to most currently used anti-malarial drugs is a major problem in malaria control along the Thai-Myanmar and Thai-Cambodia borders. Quinine (QN) with tetracycline/doxycycline has been used as the second-line treatment for uncomplicated falciparum malaria. In addition, QN monotherapy has been the first-line treatment for falciparum malaria in pregnant women. However, reduced in vitro and in vivo responses to QN have been reported. To date, a few genetic markers for QN resistance have been proposed includingPlasmodium falciparumchloroquine resistance transporter (pfcrt),P. falciparummultidrug resistance 1 (pfmdr1), andP. falciparum Na⁺/H⁺exchanger(pfnhe-1). This study was to investigate the role of thepfmdr1andpfnhe-1gene onin vitroQN sensitivity in Thai isolates ofP. falciparum.Methods: Eighty-five Thai isolates ofP. falciparumfrom the Thai-Myanmar and Thai-Cambodia borders from 2003-2008 were determined forin vitroQN sensitivity using radioisotopic assay. Polymorphisms of thepfmdr1andpfnhe-1gene were determined by PCR-RFLP and sequence analysis. Associations between thein vitroQN sensitivity and the polymorphisms of thepfmdr1andpfnhe-1gene were evaluated.Results: The mean QN IC₅₀was 202.8 nM (range 25.7-654.4 nM). Only four isolates were QN resistant when the IC₅₀of >500 nM was used as the cut-off point. Significant associations were found between thepfmdr1mutations at codons N86Y and N1042D andin vitroQN sensitivity. However, no associations with the number of DNNND, DDNNNDNHNDD, and NHNDNHNNDDD repeats in the microsatellite ms4760 of thepfnhe-1gene were identified.Conclusion: Data from the present study put doubt regarding thepfnhe-1gene as to whether it could be used as the suitable marker for QN resistance in Thailand. In contrast, it confirms the influence of thepfmdr1gene onin vitroQN sensitivity.

Dengue virus (DENV) is a mosquito-borne flavivirus responsible for life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). The viral replication machinery containing the core non-structural protein 5 (NS5) is implicated in severe dengue symptoms but molecular details remain obscure. To date, studies seeking to catalog and characterize interaction networks between viral NS5 and host proteins have been limited to the yeast two-hybrid system, computational prediction, and co-immunoprecipitation (IP) of ectopically expressed NS5. However, these traditional approaches do not reproduce a natural course of infection in which a number of DENV NS proteins colocalize and tightly associate during the replication process. Here, we demonstrate the development of a recombinant DENV that harbors a TAP tag in NS5 to study host-virus interactions in vivo. We show that our engineered DENV was infective in several human cell lines and the tags were stable over multiple viral passages, suggesting negligible structural and functional disturbance of NS5. We further provide proof-of-concept for the use of rationally tagged virus by revealing a high confidence NS5 interaction network in human hepatic cells. Our analysis uncovered previously unrecognized hnRNP complexes and several low-abundance fatty acid metabolism genes, which have been implicated in viral life cycle. This study sets a new standard for investigation of host-flavivirus interaction.