Use and reliability of multiplex bead-based assays (Luminex) at Containment Level 4

Pathogenesis of Rift Valley Fever Virus in a BALB/c Mouse Model Is Affected by Virus Culture Conditions and Sex of the Animals

Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic pathogen causing disease in livestock and humans. Whilst initially restricted to the African continent, recent spread to the Arabian Peninsula has highlighted the likelihood of entry into new regions. Due to the absence of a regulatory-approved human vaccine, work is ongoing to develop and assess countermeasures. As such, small animal models play a pivotal role in providing information on disease pathogenesis and elucidating which intervention strategies confer protection. To develop and establish the BALB/c mouse model, we challenged mice with RVFV grown from two separate cell lines: one derived from mosquitoes (C6/36) and the other mammalian derived (Vero E6). Following infection, we assessed the clinical course of disease progression at days 1 and 3 post-challenge and evaluated viral tropism and immune analytes. The results demonstrated that RVFV infection was affected by the cell line used to propagate the challenge virus, with those grown in insect cells resulting in a more rapid disease progression. The lowest dose that caused uniform severe disease remained the same across both virus preparations. In addition, to demonstrate reproducibility, the lowest dose was used for a subsequent infection study using male and female animals. The results further demonstrated that male mice succumbed to infection more rapidly than their female counterparts. Our results establish an RVFV mouse model and key parameters that affect the course of disease progression in BALB/c mice.

Analgecine protects against cerebral ischemia-reperfusion through apoptosis inhibition and anti-neuroinflammation in rats

Stroke influence the quality of life of patients and leave big public health issues as acute cerebrovascular disease all over the world. Analgecine (AGC) relieves pain and accelerates repair of nerve injury. This current study aims to observe the pharmacological effects and related mechanisms of AGC in cerebral ischemic stroke among middle cerebral artery ischemia-reperfusion (MCAO) rats. After seven days of AGC administration, motor function was enhanced as evidenced by the prehensile traction test. Morphological ameliorations were observed by immunohistochemistry analysis. The protein expression levels of HSP70, Bcl-2, Bax, TRAF-6, MyD88, BDNF, NGF, pCREB, CREB, pTrkB, TrkB, pAKT and AKT were estimated by western blot. Meanwhile, AGC alleviated MCAO-induced inflammation chiefly by decreasing inflammatory cytokines in rat brain tissues. These results above suggested that MCAO-caused brain infarction was obviously alleviated by AGC. The immunohistochemistry data showed that AGC reduced neuronal injury and apoptosis, and inhibited microglia and astrocytes activation. The protein results suggested the expression of apoptosis-relevant proteins decreased among AGC treated groups and the neurotrophin related proteins were obviously enhanced by CREB/BDNF/TrkB/AKT and HSP70/Bcl-2/Bax pathways. Collectively, the results demonstrated that AGC primarily promoted neuro-nutrition, reduced the injury of nerve apoptosis and ameliorated neuroinflammation. In summary, AGC played a neuroprotective role, which had provided reliable evidence for AGC to be a potential drug in treating stroke.

Impact of Viral Decontamination Method on Cytokine Profile of COVID-19 Patients

COVID-19 related morbidity and mortality have been often attributed to an exaggerated immune response. The role of cytokines and chemokines in COVID-19 and their contributions to illness severity are known, and thus their profiling from patient bronchoalveolar lavage (BAL) samples would help in understanding the disease progression. To date, limited studies have been performed on COVID-19 BAL samples, as the manipulation of such specimens (potentially containing live viruses) requires several laboratorial precautions, such as personnel training and special equipment, a requirement that not all laboratories can fulfil. Here, we assessed two fast and easily applicable methods (ultrafiltration and ultraviolet-C irradiation) for their impact on viral load removal or inactivation, respectively and on cytokine profiles preservation. Eight samples of BAL fluids from SARS-CoV2 patients with high viral load were tested. For both methods, complete removal was confirmed by lack of viral replication in Vero E6 cells and by RT-qPCR. Although both methods showed to remove completely the active SARS-CoV2 viral load, only UVC treatment has little or no quantitative effect on total cytokines/chemokines measurements, however cytokines profile and relative ratios are preserved or minimally altered when compared data obtained by the two different decontamination methods. Sample preparation and manipulation can greatly affect the analytical results; therefore, understanding if changes occurred after sample processing is of outmost importance for reliable data and can be useful to improve clinical practice.

Tetrahydroxy stilbene glycoside attenuates acetaminophen-induced hepatotoxicity by UHPLC-Q-TOF/MS-based metabolomics and multivariate data analysis

Tetrahydroxy stilbene glycoside (TSG) is a main active compound in Polygonum multiflorum. Acetaminophen (APAP) is a well-known analgesic and antipyretic drug. It is considered to be safe within a therapeutic range, in case of acute intoxication hepatotoxicity occurs. This present study aims to observe TSG-provided alleviation on APAP-induced hepatoxicity in C57BL/6 mice. APAP performs extensive necrosis and dissolves nucleus suggesting liver damage from hepatic histopathology. Serum alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and alkaline phosphatase analysis and liver histological evaluation showed that TSG reduced the hepatotoxicity induced by a toxic dose of APAP. Moreover, TSG alone had no hepatotoxicity. TSG eliminated hepatic glutathione depletion and cysteine adducts formation. It also reduced the expression of interleukin-10 and lowered the production of reactive oxygen species in liver tissues. Luminex was used to detect cytokine production in different groups. Herein, we used an untargeted metabolomics approach by performing ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry on treated mice to identify metabolic disruptions under APAP and TSG. Major alterations were observed for purine metabolism, amino acid metabolism, and fatty acid metabolism. These data provide metabolic evidence and biomarkers in the liver that the ABC transporters, Glycine serine and threonine metabolism, and Choline metabolism in cancer changed the most. These targets of metabolites have the potential to improve our understanding of homeostatic. Meanwhile, these metabolites revealed that TSG can alleviate inflammation caused by APAP and promote the activity of intrinsic antioxidants. In summary, TSG can regulate lipid metabolism, promote the production of antioxidant enzymes, and decrease the inflammatory response.

Tetrahydroxy stilbene glycoside alleviated inflammatory damage by mitophagy via AMPK related PINK1/Parkin signaling pathway

Alzheimer's disease (AD) is an irreversible neurodegenerative brain disorder with complex pathogenesis. The fibrillar peptide β-amyloid (Aβ) has a chief function in the pathogenesis of AD. Emerging evidence has indicated that there is a tight relationship between inflammation, mitochondrial dysfunction and Aβ formation. 2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside (TSG) is one of the main active components extracted from Polygonum multiflorum. Recent research corroborated the beneficial roles of TSG in alleviating the learning and memory of AD models. Unfortunately, the underlying mechanism of TSG remains poorly elucidated. The purpose of the present study was to investigate the effects of TSG on LPS/ATP and Aβ_25-35-induced inflammation in microglia and neurons and its underlying molecular mechanisms. Our results found that treatment with TSG significantly attenuated the secretion of inflammatory cytokines, reduced NLRP3 inflammasome, and regulated mitophagy. TSG efficiently alleviated LPS-induced inflammatory response by inhibiting the NLRP3 signaling pathway both in microglia and neuron. Meanwhile, TSG promoted autophagy involved in the AMPK/PINK1/Parkin signaling pathway, which may contribute to the protective activity. Additional mechanistic investigations to evaluate the dependence of the neuroprotective role of TSG on PINK1 revealed that a lack of PINK1 inhibited autophagy, especially mitophagy in microglia. Importantly, knockdown of PINK1 or Parkin by siRNA or CRISPR/Cas9 system abolished the protective effects of TSG. In conclusion, these phenomena suggested that TSG prevented LPS/ATP and Aβ-induced inflammation via AMPK/PINK1/Parkin-dependent enhancement of mitophagy. We found the neuroprotective effect of TSG, suggesting it may be beneficial for AD prevention and treatment by suppressing the activation of inflammation.

[Multiplex analysis on the luminex platform in complex estimation of cardiovascular biomarker dynamics in patients with acute myocardial infarction.]

The multimarker approach more accurately reflects the key mechanisms of pathogenesis and biochemical interactions, compared with the use of individual indicators. It is a reason of steadily growing interest in the development and use of various combinations of biomarkers in assessing the prognosis and stratification of cardiovascular risk in patients with a wide range of cardiological profiles. Multiplex analysis technology on the Luminex platform is the best tool for the simultaneous quantitative determination of a complex of different biomarkers in a single. Using the MILLIPLEX^® MAP Human Cardiovascular Disease Panel, a multiplefold increase of FABP, Troponin I, CK-MB, BNP, Nt-proBNP, BNP in the first 24 hours after MI, decreasing in 6 months with a high degree of confidence, was shown. There were no differences in the content of LIGHT between the stages of observation, as well as in comparison with the reference range. The content of LIGHT on the first day of MI showed strong positive associations with markers of damage of myocardium and myocardial stress. On the first day of MI, a significant increase in the content of ESM-1, decreasing in 6 months after MI to the reference values was found. Strong positive associations of ESM-1 with Troponin I and BNP levels were established. A significant increase of proinflammatory cytokine OSM on the first day of MI, decreasing in the late post-infarction period to reference values was shown. Correlation analysis revealed direct relationships of OSM with Troponin I, CK-MB, Nt-proBNP and BNP. The use of the MILLIPLEX^® MAP Human Cardiovascular Disease Panel 1 diagnostic multimarker panel allowed for the simultaneous quantitative analysis of 11 biochemical parameters, associated with inflammation, atherogenesis, endothelial dysfunction, ischemia and myocardial necrosis. The results can be used to improve the effectiveness of complex diagnostics in patients with primary myocardial infarction with ST segment elevation.

Lineage-dependent differences of Zika virus infection in a susceptible mouse model are associated with different profiles of cytokines, chemokines, growth factors and acute phase proteins

Zika virus (ZIKV) is phylogenetically divided into two lineages comprising African (ZIKV^AF) and Asian (ZIKV^AS) genotypes. In the type-I interferon receptor deficient mouse model, ZIKV^AF causes severe disease with all mice meeting humane endpoints with doses as low as 10 plaque-forming units (pfu) whereas a much milder infection is seen after challenge with ZIKV^AS, including with doses as high as 10⁶ pfu. Using this mouse model, the elucidation of cytokine, chemokine, growth factor and acute phase protein responses over the course of infection were studied to determine whether these analytes contributed to the stark difference in clinical outcome. Results demonstrated some significant differences, with the ZIKV^AF infection being associated with increases in a higher number of biomarkers than ZIKV^AS. When low (10 pfu) and high (10⁶ pfu) challenge doses were compared, animals given the lower virus inoculum showed a wider range of responses, indicating a different disease progression compared to those challenged with high doses. These results aid with elucidating the different outcomes with the two lineages of ZIKV and with future work to assess pathogenicity of virus infection.