Comparison of microscopic and xpert MTB diagnoses of presumptive mycobacteria tuberculosis infection: retrospective analysis of routine diagnosis at Cape Coast Teaching Hospital.

INTRODUCTION: Tuberculosis is a global health problem that causes 1. 4 million deaths every year. It has been estimated that sputum smear-negative diagnosis but culture-positive pulmonary TB diagnosis contribute to 12.6% of pulmonary TB transmission. TB diagnosis by smear microscopy smear has a minimum detection limit (LOD) of 5,000 to 10,000 bacilli per milliliter (CFU/ml) of sputum result in missed cases and false positives. However, GeneXpert technology, with a LOD of 131-250 CFU/ml in sputum samples and its implementation is believe to facilitate early detection TB and drug-resistant TB case. Since 2013, Ghana health Service (GHS) introduce GeneXpert MTB/RIF diagnostic in all regional hospitals in Ghana, however no assessment of performance between microscopy and GeneXpert TB diagnosis cross the health facilities has been reported. The study compared the results of routine diagnoses of TB by microscopy and Xpert MTB from 2016 to 2020 at the Cape Coast Teaching Hospital (CCTH). METHODS: The study compared routine microscopic and GeneXpert TB diagnosis results at the Cape Coast Teaching Hospital (CCTH) from 2016 to 2020 retrospectively. Briefly, sputum specimens were collected into 20 mL sterile screw-capped containers for each case of suspected TB infection and processed within 24 h. The samples were decontaminated using the NALC-NaOH method with the final NaOH concentration of 1%. The supernatants were discarded after the centrifuge and the remaining pellets dissolved in 1-1.5 ml of phosphate buffer saline (PBS) and used for diagnosis. A fixed smears were Ziehl-Neelsen acid-fast stain and observed under microscope and the remainings were used for GeneXpert MTB/RIF diagnosis. The data were analyze using GraphPad Prism. RESULTS: 50.11% (48.48-51.38%) were females with an odd ratio (95% CI) of 1.004 (0.944-1.069) more likely to report to the TB clinic for suspected TB diagnosis. The smear-positive cases for the first sputum were 6.6% (5.98-7.25%), and the second sputum was 6.07% (5.45-6.73%). The Xpert MTB-RIF diagnosis detected 2.93% (10/341) (1.42-5.33%) in the first and 5.44% (16/294) (3.14-8.69%) in the second smear-negative TB samples. The prevalence of Xpert MTB-RIF across smear positive showed that males had 56.87% (178/313) and 56.15% (137/244) and females had 43.13% (135/313) and 43.85% (107/244) for the first and second sputum. Also, false negative smears were 0.18% (10/5607) for smear 1 and 0.31% (16/5126) for smear 2. CONCLUSION: In conclusion, the study highlights the higher sensitivity of the GeneXpert assay compared to traditional smear microscopy for detecting MTB. The GeneXpert assay identified 10 and 16 positive MTB from smear 1 and smear 2 samples which were microscopic negative.

Candidiasis profile at the outpatient department of the university of cape coast hospital in the central region of Ghana: a retrospective study.

INTRODUCTION: Vulvovaginal candidiasis (VVC) is a public health problem with an estimated 138 million women globally experiencing recurrent VVC annually. The microscopic diagnosis of VVC has low sensitivity, but it remains an essential tool for diagnosis as the microbiological culture methods are limited to advanced clinical microbiology laboratories in developing countries. The study retrospectively analyzed the presence of red blood cells (RBCs), epithelial cells (ECs), pus cells (PCs) and Candida albicans positive in wet mount preparation of urine or high vaginal swabs (HVS) samples to test for their sensitivity and specificity for the diagnosis of candidiasis. METHODS: The study is a retrospective analysis at the Outpatient Department of the University of Cape Coast between 2013 and 2020. All urine and high vagina swabs (HVS) cultures samples using Sabourauds dextrose agar with wet mount data were analyzed. 2 × 2 contingency diagnostic test was used to ascertain the diagnostic accuracy of red blood cells (RBCs), epithelial cells (ECs), pus cells (PCs), and Candida albicans positive in wet mount preparation of urine or high vaginal swabs (HVS) samples for the diagnosis of candidiasis. The association of candidiasis among patients' demographics was analyzed using relative risk (RR) analysis. RESULTS: The high prevalence of candida infection was among female subjects 97.1% (831/856) compared to males 2.9% (25/856). The microscopic profiles which characterized candida infection were pus cells 96.4% (825/856), epithelial cells 98.7% (845/856), red blood cells (RBCs) 7.6% (65/856) and Candida albicans positive 63.2% (541/856). There was a lower risk of Candida infections among male patients compared to female patients RR (95% CI) = 0.061 (0.041-0.088). The sensitivity (95%) for detecting Candida albicans positive and red blood cells (0.62 (0.59-0.65)), Candida albicans positive and pus cells (0.75 (0.72-0.78)) and Candida albicans positive and epithelial cells (0.95 (0.92-0.96)) with corresponding specificity (95% CI) of 0.63 (0.60-0.67), 0.69 (0.66-0.72) and 0.74 (0.71-0.76) were detected among the high vaginal swab samples. CONCLUSION: In conclusion, the study has shown that the presence of PCs, ECs, RBCs or ratio of RBCs/ECs and RBCs/PCs in the wet mount preparation from urine or HVS can enhance microscopic diagnosis of VVC cases.

Intestinal microbiome-rheumatoid arthritis crosstalk: The therapeutic role of probiotics.

Rheumatoid arthritis (RA) is a common systemic autoimmune disease with a global health importance. It is characterized by long-term complications, progressive disability and high mortality tied to increased social-economic pressures. RA has an inflammatory microenvironment as one of the major underlying factors together with other complex processes. Although mechanisms underlying the triggering of RA remain partially elusive, microbiota interactions have been implicated. Again, significant alterations in the gut microbiome of RA patients compared to healthy individuals have intimated a chronic inflammatory response due to gut dysbiosis. Against this backdrop, myriads of studies have hinted at the prospective therapeutic role of probiotics as an adjuvant for the management of RA in the quest to correct this dysbiosis. In this article, the major gut microbiome alterations associated with RA are discussed. Subsequently, the role of the gut microbiome dysbiosis in the initiation and progression of RA is highlighted. Lastly, the effect and mechanism of action of probiotics in the amelioration of symptoms and severity of RA are also espoused. Although strain-specific, probiotic supplementation as adjuvant therapy for the management of RA is very promising and warrants more research.

Fibroblast growth factor 21 attenuates the progression of hyperuricemic nephropathy through inhibiting inflammation, fibrosis and oxidative stress.

Elevated levels of circulating fibroblast growth factor 21 (FGF21) have been reported in patients with hyperuricemia. However, the effect of FGF21 in hyperuricemic nephropathy (HN) remains unexplored. Here, we investigated the effect and mechanism of action of FGF21 on HN. HN model was induced with adenine and potassium oxysalt in wild-type C57BL/6 mice and FGF21-/- mice. For in vitro studies, human renal tubular epithelial (HK-2) cells were exposed to uric acid with/without FGF21 or ß-Klotho-siRNA. Here, we reported aggravated renal dysfunction and structural damage in the FGF21-/- mice compared to the wild-type mice. These were evident in the upsurge of inflammatory factors IL-1ß, TNF-α, IL-6, and IL-18; fibrotic markers Collagen I and α-SMA; and oxidation products ROS and MDA. However, exogenous administration of FGF21 to wild-type HN mice significantly reversed these negative effects. In terms of mechanism, FGF21 significantly inhibited NF-κB/NLRP3 and TGF-ß1/Smad3 pathways and promoted nuclear translocation of Nrf2 both in vivo and in vitro. Furthermore, the silencing of ß-Klotho was marked by the attenuation of the improved effect of FGF21 on cell damage. In conclusion, our studies revealed that exogenous FGF21 treatment significantly improved HN, which was achieved by the inhibition of inflammation, fibrosis, and oxidative stress.

Prevalence and antimicrobial resistance patterns of microbes isolated from individuals attending private diagnostic centre in Cape Coast Metropolis of Ghana.

The evidence of rising numbers of multidrug-resistant organisms requires the implementation of effective stewardship programs. However, this should be informed by evidence-based knowledge of local antimicrobial resistance patterns. The current study aims to establish the prevalence of common pathogenic microbes including their antimicrobial susceptibility patterns and distribution in the Cape Coast Metropolis. This was a retrospective study where microbial culture and antimicrobial susceptibility records for 331 patients were reviewed from January to December 2019, at a private health centre. All data were analysed using Excel (Microsoft Office, USA), SPSS and GraphPad Prism 8 software programs. Among the samples tested, 125 (37.76%) were positive for microbes with high vaginal swab (HVS) samples recording the highest number of pathogens (44%), followed by urine (40%) and both pleural and semen samples having the least (0.3% each). Again, gram-negative isolates were more prevalent than the gram-positive isolates. The prevalence of antimicrobial resistance was very significant with isolates resistant to more than one antibiotic (P < 0.05). Escherichia coli showed the highest level of resistance, followed by Citrobacter spp. These were followed by Klebsiella spp., Staphylococcus spp., Coliforms, Pseudomonas spp., Commensals and Candida spp. The high resistance pattern suggests an inevitable catastrophe requiring continuous monitoring and implementation of effective antibiotic stewardship.

Genetics of cerebral malaria: pathogenesis, biomarkers and emerging therapeutic interventions.

BACKGROUND: Cerebral malaria (CM) is a preeminent cause of severe disease and premature deaths in Sub-Saharan Africa, where an estimated 90% of cases occur. The key features of CM are a deep, unarousable coma that persists for longer than 1 h in patients with peripheral Plasmodium falciparum and no other explanation for encephalopathy. Significant research efforts on CM in the last few decades have focused on unravelling the molecular underpinnings of the disease pathogenesis and the identification of potential targets for therapeutic or pharmacologic intervention. These efforts have been greatly aided by the generation and study of mouse models of CM, which have provided great insights into key events of CM pathogenesis, revealed an interesting interplay of host versus parasite factors that determine the progression of malaria to severe disease and exposed possible targets for therapeutic intervention in severe disease. MAIN BODY: This paper reviews our current understanding of the pathogenic and immunologic factors involved in CM. We present the current view of the roles of certain gene products e.g., the var gene, ABCA-1, ICAM-1, TNF-alpha, CD-36, PfEMP-1 and G6PD, in CM pathogenesis. We also present alterations in the blood-brain barrier as a consequence of disease proliferation as well as complicated host and parasite interactions, including the T-cell immune reaction, reduced deformation of erythrocytes and cytoadherence. We further looked at recent advances in cerebral malaria treatment interventions by emphasizing on biomarkers, new diagnostic tools and emerging therapeutic options. CONCLUSION: Finally, we discuss how the current understanding of some of these pathogenic and immunologic factors could inform the development of novel therapeutic interventions to fight CM.

Antibiotic-resistant pathogenic bacterial isolates from patients attending the outpatient department of university of Cape Coast hospital, Ghana: A retrospective study between 2013-2015.

Uropathogenic Escherichia coli (E. coli) is an important urinary tract infection (UTI) that has been associated with both complicated and uncomplicated disease conditions. The global emergence of multiple drug-resistant (MDR) and extended-spectrum ß-lactamase (ESBL) is of public health concern as the resistance limits the current treatment options. The objective of this study was to analyze the antibiotic-resistant patterns among the uropathogenic E. coli isolates at the University of Cape Coast (UCC) hospital between 2013 and 2015 as baseline data to understand the current antibiotic resistance situation within UCC and its environs. A retrospective cross-sectional study of bacteria isolates at UCC hospital from January 2013 to December 2015 were analyzed. A standard biochemical and antibiotic susceptibility tests were performed using Kirby-Bauer NCCLs modified disc diffusion technique. The network of interaction between pathogenic isolates and antibiotic resistance was performed using Cytoscape software. Statistical significance was tested using ANOVA and one-sample Wilcoxon test. The overall E. coli prevalence was 15.76% (32/203); females had the highest infection of 17.33% (26/150) compared to male subjects who had 11.32% (6/53) out of all the pathogenic infections. The E. coli prevalence among the age categories were 2/21 (9.52%), 27/154 (17.53%) and 4/21 (19.05%) among ≤20 years, 21-40 years and 41-60 years respectively. The isolated resistant pathogens exhibited different antibiotic resistance patterns. An interaction network of nodes connecting to other nodes indicating positive correlations between the pathogens and antibiotic resistance was established. Escherichia coli, Citrobacter spp, Klebsiella spp among other isolated pathogens formed higher centrality in the network of interaction with antibiotic resistance. The individual E. coli isolates showed a significant difference in the mean ± SD (95% CI) pattern of antibiotic resistance, 2.409±1.205 (1.828-2.990), χ2 = 36.68, p<0.0001. In conclusion, the study reports the interaction of E. coli isolates at UCC hospital and its antibiotic-resistant status between 2013 and 2015. This data forms the baseline information for assessing the current antibiotic status in UCC and its environs.

The emergence of chloroquine-sensitive Plasmodium falciparum is influenced by selected communities in some parts of the Central Region of Ghana.

BACKGROUND: The return of chloroquine-sensitive Plasmodium falciparum in sub-Saharan Africa countries offers the opportunity for the reintroduction of chloroquine (CQ) either in combination with other drugs or as a single therapy for the management of malaria. This study assesses the influence of individual study sites on the selection of CQ sensitive P. falciparum markers in the Central region of Ghana. METHODS: Genomic DNA was extracted from an archived filter paper blood blot from Cape Coast, Elmina, Assin Fosu, and Twifo Praso using the Chelex DNA extraction method. The age metadata of the patients from whom the blood spots were taken was collected. The prevalence of CQ-sensitive markers of pfcrt K76 and pfmdr1 N86 was performed using nested PCR and RFLP. The data were analysed using Chi-square and Odd ratio. RESULTS: The overall prevalence of CQ-sensitive P. falciparum markers, pfcrt K76 and pfmdr1 N86 in the Central Region of Ghana were 142 out of 184 (77.17%) and 180 out of 184 (97.83%), respectively. The distribution of pfcrt K76 was assessed among the age groups per the individual study sites. 12 out of 33 (36.36%), 8 out of 33 (24.24%) and 6 out of 33 (18.18%) of pfcrt K76 CQ-sensitive marker were isolated from age 0 to 5 years, 16 to 30 years and 31 to 45 years old respectively at Cape Coast. Assin Fosu and Twifo Praso had the highest pfcrt K76 prevalence in 0-5 years, followed by 16-30 years and 6-15 years of age. The results showed that there was a significant prevalence of pfcrt K76 in all study sites; Cape Coast (χ2 = 26.48, p < 0.0001), Assin Fosu (χ2 = 37.67, p < 0.0001), Twifo Praso (χ2 = 32.25, p < 0.0001) and Elmina (χ2 = 17.88, p < 0.0001). Again, the likelihood to detect pfcrt K76 (OR (95% CI) was 7.105 (3.118-17.14), p < 0.0001 and pfmdr1 (2.028 (1.065-3.790), p < 0.001) among P. falciparum isolates from Cape Coast to be seven times and two times, respectively. CONCLUSION: The study showed a significant selection and expansion of chloroquine-sensitive P. falciparum markers in all the selected study areas in the Central region. This finding has a significant implication for the future treatment, management, and control of P. falciparum malaria.

Fibroblast growth factor 21: a novel long-acting hypoglycemic drug for canine diabetes.

Currently, insulin is commonly used in the clinical management of canine diabetes. However, it must be injected preprandially causing much inconvenience to the owners. Therefore, the development of long-acting hypoglycemic agents has attracted much attention in the scientific community. This study aimed to investigate the long-acting hypoglycemic effect of canine fibroblast growth factor 21 (cFGF-21) in diabetic dogs. Diabetic dogs were administered with cFGF-21, polyethylene glycol-modified cFGF-21 (PEG-cFGF-21), or insulin once a day, once every 2, 3, or 4 days subcutaneously. The results showed that cFGF-21 and PEG-cFGF-21 maintained blood glucose comparable to normal levels for 2 and 3 days respectively while insulin maintained the blood glucose for only 2 h after a single injection. After treatment with cFGF-21, oral glucose tolerance test (OGTT) was significantly improved with glycosylated hemoglobin (HbA1c) close to the normal levels. In addition, cFGF-21 significantly repaired islet ß cells, increased insulin content, and protected the pancreas from streptozotocin-induced injury. Furthermore, cFGF-21 exhibited both antioxidant and anti-inflammatory properties in the pancreas. We conclude, therefore, that cFGF-21 and PEG-cFGF-21 can maintain blood glucose comparable to normal levels for 2 and 3 days respectively after a single dose. The long-acting efficacy of cFGF-21 can be attributed to improvement in oxidative stress and the reduction of inflammation in the pancreas.

Autophagy in the control and pathogenesis of parasitic infections.

BACKGROUND: Autophagy has a crucial role in the defense against parasites. The interplay existing between host autophagy and parasites has varied outcomes due to the kind of host cell and microorganism. The presence of autophagic compartments disrupt a significant number of pathogens and are further cleared by xenophagy in an autolysosome. Another section of pathogens have the capacity to outwit the autophagic pathway to their own advantage. RESULT: To comprehend the interaction between pathogens and the host cells, it is significant to distinguish between starvation-induced autophagy and other autophagic pathways. Subversion of host autophagy by parasites is likely due to differences in cellular pathways from those of 'classical' autophagy and that they are controlled by parasites in a peculiar way. In xenophagy clearance at the intracellular level, the pathogens are first ubiquitinated before autophagy receptors acknowledgement, followed by labeling with light chain 3 (LC3) protein. The LC3 in LC3-associated phagocytosis (LAP) is added directly into vacuole membrane and functions regardless of the ULK, an initiation complex. The activation of the ULK complex composed of ATG13, FIP200 and ATG101causes the initiation of host autophagic response. Again, the recognition of PAMPs by conserved PRRs marks the first line of defense against pathogens, involving Toll-like receptors (TLRs). These all important immune-related receptors have been reported recently to regulate autophagy. CONCLUSION: In this review, we sum up recent advances in autophagy to acknowledge and understand the interplay between host and parasites, focusing on target proteins for the design of therapeutic drugs. The target host proteins on the initiation of the ULK complex and PRRs-mediated recognition of PAMPs may provide strong potential for the design of therapeutic drugs against parasitic infections.

Fibroblast Growth Factor-21 ameliorates hepatic encephalopathy by activating the STAT3-SOCS3 pathway to inhibit activated hepatic stellate cells.

Neurological dysfunction, one of the consequences of acute liver failure (ALF), and also referred to as hepatic encephalopathy (HE), contributes to mortality posing challenges for clinical management. FGF21 has been implicated in the inhibition of cognitive decline and fibrogenesis. However, the effects of FGF21 on the clinical and molecular presentations of HE has not been elucidated. HE was induced by fulminant hepatic failure using thioacetamide (TAA) in male C57BL/6J mice while controls were injected with saline. For two consecutive weeks, mice were treated intraperitoneally with FGF21 (3 mg/kg) while controls were treated with saline. Cognitive, neurological, and activity function scores were recorded. Serum, liver, and brain samples were taken for analysis of CCL5 and GABA by ELISA, and RT qPCR was used to measure the expressions of fibrotic and pro-inflammatory markers. We report significant improvement in both cognitive and neurological scores by FGF21 treatment after impairment by TAA. GABA and CCL5, key factors in the progression of HE were also significantly reduced in the treatment group. Furthermore, the expression of fibrotic markers such as TGFß and Col1 were also significantly downregulated after FGF21 treatment. TNFα and IL-6 were significantly reduced in the liver while in the brain, TNFα and IL-1 were downregulated. However, both in the liver and the brain, IL-10 was significantly upregulated. FGF21 inhibits CXCR4/CCL5 activation and upregulates the production of IL-10 in the damaged liver stimulating the production pro-inflammatory cytokines and apoptosis of hepatic stellate cells through the STAT3-SOCS3 pathway terminating the underlying fibrosis in HE.

Clearing or subverting the enemy: Role of autophagy in protozoan infections.

The protozoan parasites are evolutionarily divergent, unicellular eukaryotic pathogens representing one of the essential sources of parasitic diseases. These parasites significantly affect the economy and cause public health burdens globally. Protozoan parasites share many cellular features and pathways with their respective host cells. This includes autophagy, a process responsible for self-degradation of the cell's components. There is conservation of the central structural and functional machinery for autophagy in most of the eukaryotic phyla, however, Plasmodium and Toxoplasma possess a decreased number of recognizable autophagy-related proteins (ATG). Plasmodium noticeably lacks clear orthologs of the initiating kinase ATG1/ULK1/2, and both Plasmodium and Toxoplasma lack proteins involved in the nucleation of autophagosomes. These organisms have essential apicoplast, a plastid-like non-photosynthetic organelle, which is an adaptation that is used in penetrating the host cell. Furthermore, available evidence suggests that Leishmania, an intracellular protozoan parasite, induces autophagy in macrophages. The autophagic pathway in Trypanosoma cruzi is activated during metacyclogenesis, a process responsible for the infective forms of parasites. Therefore, numerous pathogens have developed strategies to impair the autophagic mechanism in phagocytes. Regulating autophagy is essential to maintain cellular health as adjustments in the autophagy pathway have been linked to the progression of several physiological and pathological conditions in humans. In this review, we report current advances in autophagy in parasites and their host cells, focusing on the ramifications of these studies in the design of potential anti-protozoan therapeutics.

ART Regimen and Other Sociodemographics Do Not Affect Cytokine Expression in HIV Patients in Ghana.

BACKGROUND: HIV infection is marked by the production of cytokines by infected cells and cells of the immune system. Variations in the levels of cytokine in HIV-infected individuals significantly impact the role of the immune system with the possibility to affect the course of HIV disease by either exacerbating or suppressing HIV replication. AIM: The study sought to investigate the effect of sociodemographic indices, clinical laboratory parameters, and ART regimen on Th1, Th2, and Th17 cytokines in HIV patients. MATERIALS AND METHODS: A total of two hundred (200) HIV patients on either the first or second line of ART were recruited into the study. Sociodemographic indices were collected using researcher-administered questionnaires. Serum concentrations of two major immune-promoting cytokines, IL-12 and IFN-γ, and immune-suppressive cytokines, IL-10 and IL-17, were measured using enzyme-linked immunosorbent assay (ELISA). T-test and chi-square were used to compare mean scores, while correlation (Pearson's correlation) and linear regression analyses were also performed with the statistical significance set at p < 0.05. RESULTS: The mean age of the participants was (45.54 ± 0.7846) years with a greater proportion (84.5%) between 31 and 60 years. The mean interferon-gamma (INF-γ), interleukin- (IL-) 10, interleukin-12, and interleukin-17 were estimated to be 349.9 ± 8.391 pg/ml, 19.32 ± 0.4593 pg/ml, 19.23 ± 0.3960 pg/ml, and 24.6 ± 0.6207 pg/ml, respectively. Although INF-γ and IL-17 levels were relatively higher in males compared to females, it was vice versa for IL-10 and IL-12. However, none of these was statistically significant. Again, no significant difference was observed among all the cytokines stratified by the duration of ART, stage of HIV, and smoking status. Most importantly, stratification by either first- or second-line ART regimens recorded no significant difference in cytokine levels. Age significantly correlated inversely with IFN-γ (r = -0.27, p ≤ 0.001), IL-10 (r = -0.24, p ≤ 0.001), and IL-12 (r = -0.18, p=0.01) while duration on ART significantly correlated inversely with IFN-γ (r = -0.16, p=0.02). CD4 counts at 6 months and 12 months on ART correlated inversely with IL-17 (r = -0.17, p=0.02) and plasma viral load at 1 year (r = -0.22, p ≤ 0.001), respectively. A positive correlation was observed between IFN-γ and IL-12 (r = -0.84, p ≤ 0.001) and IL-17 (r = -0.50, p ≤ 0.001). This positive trend was repeated between IL-10 and IL-12 (r = -0.92, p ≤ 0.001) and IL-17 (r = -0.61, p ≤ 0.001). CONCLUSION: The levels of IFN-γ, IL-12, IL-17, and IL-10 are not significantly affected by sociodemographics and ART regimen. This observation shows that no significant difference was observed in cytokine levels stratified by ART regiments. This means that both regimens are effective in the suppression of disease progression.

The Clinical Importance of the Mercury Problem in Artisanal Small-Scale Gold Mining.

Artisanal small-scale mining is widely operated in various countries serving as a livelihood to many rural communities. However, it is a significant source of environmental mercury contamination which affects human health. Amalgamation and amalgam smelting, two significant steps in the artisanal small-scale mining operations generate lots of mercury vapors, leading to chronic exposure among miners. Thus, this article seeks to provide a topical review of recent findings on organ damage and metabolic disorders among mercury-exposed artisanal small-scale miners with emphasis on the contributing factors such as personal protective equipment usage and artisanal small-scale gold mining-specific occupational activities. Also, insights into the effect of mercury intoxication and mechanisms of action on organ and metabolic systems among exposed individuals are provided.

Ameliorative effects of a fusion protein dual targeting interleukin 17A and tumor necrosis factor α on imiquimod-induced psoriasis in mice.

In recent decades, biological agents such as tumor necrosis factor-α (TNF-α) inhibitors, have revolutionized the treatment of psoriasis. However, inhibition of a single cytokine may not achieve satisfactory therapeutic results. It is against this background that this research was undertaken to investigate the anti-psoriatic effect of a novel fusion protein (DTF) dual targeting TNF-α and interleukin-17 A (IL-17 A). Imiquimod (IMQ) was topically applied to the skin of mice to develop psoriasis-like skin and treated with etanercept or different doses of DTF. Results showed that DTF treatment (1 mg/kg, 3 mg/kg, 5 mg/kg) significantly attenuated IMQ-induced typical psoriasis-like inflammation, severity score, and epidermis thickening in a dose-dependent manner, and was again more efficient than etanercept (3 mg/kg) in alleviating all these parameters at the same dose. Furthermore, DTF was more potent than etanercept in suppressing the expression of inflammatory factors (IL-17 A, IL-6, IL-1ß, IL-23, IL-22 and IL-12) in the serum, spleen and psoriasis-like skin compared with etanercept at the same dose. In addition, DTF was more efficient than etanercept in reducing the expression of keratins, decreasing the mRNA expression of Ly-6 G and Ly-6C, and enhancing the expression of filaggrin and caspase 14 in IMQ-induced psoriasis-like skin. We conclude that DTF alleviates IMQ-induced psoriasis by attenuating inflammatory cascades, reducing keratinocytes proliferation and improving epidermal barrier function through suppressing TNF-α and IL-17 A signal pathways. These data suggest that DTF has potential to be a novel therapeutic candidate for psoriasis.

A novel fusion protein attenuates collagen-induced arthritis by targeting interleukin 17A and tumor necrosis factor α.

This study was undertaken to generate a novel dual targeting fusion protein (DTF), targeting tumor necrosis factor α (TNF-α) and interleukin 17A (IL-17A), and determine its anti-arthritis properties in vitro and in vivo. DTF consisted of an anti-IL-17A single chain variable fragment, a soluble TNF receptor 1, and an Fc fragment. Both clinical and histopathological evaluations suggest that DTF and etanercept can ameliorate collagen induced arthritis. However, the arthritis severity score of DTF-treated mice was lower than that of etanercept-treated mice. In addition, DTF was more potent than etanercept in decreasing the ratio of RANKL/OPG in the serum and rebalancing the population ratio of Treg/Th17 cells in the spleens. In vitro, IL-17A and TNF-α had synergistic effects in inducing the expression of inflammatory cytokines in fibroblast-like synoviocyte from RA patients (RA-FLS), human leukemia (THP-1), and rheumatoid synovial fibroblast (MH7A). IL-17A and TNF-α also had synergistic effects in inducing proliferation and migration of MH7A cells. However, we observed that DTF was more efficient than etanercept in suppressing these synergistic effects. Our results demonstrate that DTF is highly efficient in the treatment of arthritis and has the potential to overcome the limited therapeutic responses obtained with single cytokine neutralization.