SARS-CoV-2 causes human BBB injury and neuroinflammation indirectly in a linked organ chip platform

COVID-19 is a multi-system disease affecting many organs outside of the lungs, and patients generally develop varying degrees of neurological symptoms. Whereas, the pathogenesis underlying these neurological manifestations remains elusive. Although in vitro models and animal models are widely used in studies of SARS-CoV-2 infection, human organ models that can reflect the pathological alterations in a multi-organ context are still lacking. In this study, we propose a new strategy to probe the effects of SARS-CoV-2 on human brains in a linked alveolus-BBB organ chip platform. The new multi-organ platform allows to recapitulate the essential features of human alveolar-capillary barrier and blood-brain barrier in a microfluidic condition by co-culturing the organ-specific cells. The results reveal direct SARS-CoV-2 exposure has no obvious effects on BBB chip alone. While, infusion of endothelial medium from infected alveolus chips can cause BBB dysfunction and neuroinflammation on the linked chip platform, including brain endothelium disruption, glial cell activation and inflammatory cytokines release. These new findings suggest that SARS-CoV-2 could induce neuropathological alterations, which might not result from direct viral infection through hematogenous route, but rather likely from systemic inflammation following lung infection. This work provides a new strategy to study the virus-host interaction and neuropathology at an organ-organ context, which is not easily obtained by other in vitro models. This will facilitate to understand the neurological pathogenesis in SARS-CoV-2 and accelerate the development of new therapeutics. SUMMARYO_LIA linked human alveolus-BBB chip platform is established to explore the influences of SARS-CoV-2 on human brains in an organ-organ context. C_LIO_LISARS-CoV-2 infection could induce BBB injury and neuroinflammation. C_LIO_LIThe neuropathological changes are caused by SARS-CoV-2 indirectly, which might be mediated by systemic inflammation following lung infection, but probably not by direct viral neuroinvasion. C_LI

Modeling SARS-CoV-2 infection in vitro with a human intestine-on-chip device

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) has given rise to a global pandemic. The gastrointestinal symptoms of some COVID-19 patients are underestimated. There is an urgent need to develop physiologically relevant model that can accurately reflect human response to viral infection. Here, we report the creation of a biomimetic human intestine infection model on a chip system that allows to recapitulate the intestinal injury and immune response induced by SARS-CoV-2, for the first time. The microengineered intestine-on-chip device contains human intestinal epithelium (co-cultured human intestinal epithelial Caco-2 cells and mucin secreting HT-29 cells) lined in upper channel and vascular endothelium (human umbilical vein endothelial cells, HUVECs) in a parallel lower channel under fluidic flow condition, sandwiched by a porous PDMS membrane coated with extracellular matrix (ECM). At day 3 post-infection of SARS-CoV-2, the intestine epithelium showed high susceptibility to viral infection and obvious morphological changes with destruction of intestinal villus, dispersed distribution of mucus secreting cells and reduced expression of tight junction (E-cadherin), indicating the destruction of mucous layer and the integrity of intestinal barrier caused by virus. Moreover, the endothelium exhibited abnormal cell morphology with disrupted expression of adherent junction protein (VE-cadherin). Transcriptional analysis revealed the abnormal RNA and protein metabolism, as well as activated immune responses in both epithelial and endothelial cells after viral infection (e.g., up-regulated cytokine genes, TNF signaling and NF-kappa B signaling-related genes). This bioengineered in vitro model system can mirror the human relevant pathophysiology and response to viral infection at the organ level, which is not possible in existing in vitro culture systems. It may provide a promising tool to accelerate our understanding of COVID-19 and devising novel therapies.

A human disease model of SARS-CoV-2-induced lung injury and immune responses with a microengineered organ chip

Coronavirus disease 2019 (COVID-19) is a global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that seriously endangers human health. There is an urgent need to build physiological relevant human models for deep understanding the complex organ-level disease processes and facilitating effective therapeutics for COVID-19. Here, we first report the use of microengineered alveolus chip to create a human disease model of lung injury and immune responses induced by native SARS-CoV-2 at organ-level. This biomimetic system is able to reconstitute the key features of human alveolar-capillary barrier by co-culture of alveolar epithelial and microvascular endothelial cells under microfluidic flow. The epithelial cells on chip showed higher susceptibility to SARS-CoV-2 infection than endothelial cells identified by viral spike protein expression. Transcriptional analysis showed distinct responses of two cell types to SARS-CoV-2 infection, including activated type I interferon (IFN-I) signaling pathway in epithelium and activated JAK-STAT signaling pathway in endothelium. Notably, in the presence of circulating immune cells, a series of alveolar pathological changes were observed, including the detachment of endothelial cells, recruitment of immune cells, and increased production of inflammatory cytokines (IL-6, IL-8, IL-1{beta} and TNF-). These new findings revealed a crucial role of immune cells in mediating lung injury and exacerbated inflammation. Treatment with antiviral compound remdesivir could suppress viral copy and alleviate the disruption of alveolar barrier integrity induced by viral infection. This bioengineered human organ chip system can closely mirror human-relevant lung pathogenesis and immune responses to SARS-CoV-2 infection, not possible by other in vitro models, which provides a promising and alternative platform for COVID-19 research and preclinical trials.

Protective Effects of Insulin-glucose on Myocardium in Patients Receiving Combined Cardiac Valve Re-placement under Cardiopulmonary Bypass / 中国药房

OBJECTIVE:To investigate the protective effects of insulin-glucose on myocardium in patients receiving cardiac valve replacement under cardiopulmonary bypass. METHODS:Totally 120 patients receiving combined cardiac valve replacement under cardiopulmonary bypass were divided into control group and observation group according to random number table,with 60 cases in each group. All patients were given routine operation. Control group was given Thomas cardioplegia and oxygenated blood with a ratio of 1:4(V:V)to protect myocardium at 4 ℃. Besides that,the observation group was additionally given Insulin injec-tion 10 IU/L and Glucose injection 10 g/L added into Thomas cardioplegia at 4 ℃ to protect myocardium. The levels of plasma brain natriuretic peptide(BNP)and cardiac troponinⅠ(cTnⅠ)before anesthesia induction(T0),at the end of cardiopulmonary by-pass(T1),12 h(T2),24 h(T3),48 h(T4),and 72 h(T5)after surgery,the rate of recovery of automatic heartbeat after opening aor-ta,the application of vasoactive agent(dopamine)at T1 and the occurrence of postoperative complications were observed and com-pared between 2 groups. RESULTS:At T0,there was no statistical significance in the levels of plasma BNP and cTnⅠ between 2 groups(P>0.05). The levels of plasma BNP and cTnⅠin 2 groups at T1-5 were significantly higher than T0,with statistical signifi-cance(P0.05). The dos-age of dopamine (at T1) and the incidence of complications in observation group were statistically lower than control group,with statistical significance(P<0.05). No severe ADR was found in 2 groups during or after surgery. CONCLUSIONS:Insulin-glucose can alleviate myocardial damage, reduce the dosage of vasoactive agent and the incidence of postoperative complications in pa-tients receiving combined cardiac valve replacement under cardiopulmonary bypass with significant protective effect on myocardium with good safety.

Expression and identification of the ADF-linker-3-1E gene of Eimeria acervulina of chicken.

Coccidiosis is a widely distributed disease with higher mortality and morbidity, which is caused by several species of protozoan parasites belonging to the genus Eimeria and recognized as a serious challenge for the poultry industry. This research was conducted to construct the recombinant plasmid pET32a(+)-ADF-linker-3-1E of Eimeria acervulina (E. acervulina) of the chicken and test the bioactivity of the ADF-linker-3-1E protein. The ADF-linker-3-1E gene of E. acervulina of the chicken was cloned by splicing by overlap extension by the polymerase chain reaction (SOE-PCR) and then inserted into the pET32a(+) to construct the recombinant plasmid pET32a(+)-ADF-linker-3-1E. The recombinant plasmid was transformed into Escherichia coli Rosetta (DE3) competent cells and then induced by IPTG (0.6 mmol/L). The expressed product in the culture medium was identified by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The bioactivity of the ADF-linker-3-1E protein was tested by Western blotting. The result showed that the amplified ADF-linker-3-1E gene was about 1346 bp. The PCR amplification with the recombinant plasmid pET-32a(+)-ADF-linker-3-1E as a template resulted in a special band of 1346 bp. The digested products resulted in two fragments of 1346 bp target fragment and 5.9 kb pET-32a(+)-vector fragment. The results indicated that the ADF-linker3-1E gene was successfully inserted into the pET-32a(+)-vector. The expressed products in the culture medium resulted in a single band of approximately 54.8 kDa by SDS-PAGE. Western blotting analysis indicated that the recombinant protein could be reacted specifically with His-Tag(2A8) Mouse mAb. This study indicated that the ADF-linker-3-1E protein with good bioactivity was successfully obtained, which laid a foundation for the exploitation of the nuclear vaccine by using the ADF-linker-3-1E protein.

Relationship Between Thyroid Hormone and Atrial Fibrillation Prevalence in Patients With Chronic Heart Failure / 中国循环杂志

Objective: To investigate the impact of thyroid hormone on atrial ifbrillation (AF) prevalence in patients with chronic heart failure (CHF). Methods: A total of 322 non-valvular heart disease CHF patients treated in our hospital from 2011-0-01 to 2012-10-01 were retrospectively studied. Based on previous history and the ECG at admission, the patients were divided into 2 groups: AF group,n=187 and Sinus rhythm group,n=135. The proifle of serum levels of free thyroxine (FT4), free triiodothyronine (FT3), hyroid stimulating hormone (TSH) and LDL-C were examined within 24 hours of admission; 12 lead ECG and echocardiography were conducted to analyze the related factor for AF occurrence. Results: Compared with Sinus rhythm group, AF group had increased FT4 level as 14.52 (12.74, 15.85) pmol/L vs 13.11 (11.68, 14.85) pmol/L,P Conclusion: High serum level of FT4 may increase the risk AF occurrence in CHF patients.

Interventional effects of emodin on transforming growth factor-beta1/integrin-linked kinase signal way in interleukin-1beta-induced transdifferentiation of rat tubular epithelial-myofibroblasts / 中西医结合学报

To study the effects of transforming growth factor-beta1/integrin-linked kinase (TGF-beta1/ILK) signal way in interleukin-1beta (IL-1beta)-induced rat tubular epithelial-myofibroblast transdifferentiation (TEMT), and to investigate whether emodin inhibits IL-1beta-induced TEMT through the TGF-beta1/ILK signal way-dependent mechanism.