Abstract COVID-19 pathogen SARS-CoV-2 has infected hundreds of millions and caused over 5 million deaths to date. Although multiple vaccines are available, breakthrough infections occur especially by emerging variants. Effective therapeutic options such as monoclonal antibodies (mAbs) are still critical. Here, we report the development, cryo-EM structures, and functional analyses of mAbs that potently neutralize SARS-CoV-2 variants of concern. By high-throughput single cell sequencing of B cells from spike receptor binding domain (RBD) immunized animals, we identified two highly potent SARS-CoV-2 neutralizing mAb clones that have single-digit nanomolar affinity and low-picomolar avidity, and generated a bispecific antibody. Lead antibodies showed strong inhibitory activity against historical SARS-CoV-2 and several emerging variants of concern. We solved several cryo-EM structures at ∼3 Å resolution of these neutralizing antibodies in complex with prefusion spike trimer ectodomain, and revealed distinct epitopes, binding patterns, and conformations. The lead clones also showed potent efficacy in vivo against authentic SARS-CoV-2 in both prophylactic and therapeutic settings. We also generated and characterized a humanized antibody to facilitate translation and drug development. The humanized clone also has strong potency against both the original virus and the B.1.617.2 Delta variant. These mAbs expand the repertoire of therapeutics against SARS-CoV-2 and emerging variants.
Peritoneal fibrosis (PF) is a common complication in patients receiving long-term peritoneal dialysis, which results in damage to peritoneal functions. Epithelial-mesenchymal transition (EMT) is a key step in the early pathogenesis of PF. Increasing evidence has shown that signal transducer and activator of transcription 3 (STAT3) signaling pathway is involved in EMT and tissue fibrosis by interacting with distinct EMT-inducing molecules, including transforming growth factor (TGF)-β and advanced glycation end products (AGEs). This study investigated the involvement of STAT3 in the PF process.We used high glucose-treated human peritoneal mesothelial cell line HMrSV5 as an in vitro model to expose the peritoneal mesothelial cells to high-glucose dialysate. Expression of EMT markers was detected by qRT-PCR. Accumulation of methylglyoxal (MGO) and AGEs in the culture supernatant were measured by enzyme-linked immunosorbent assay. Phosphorylation of STAT3 was assessed by Western blot.Results showed that high glucose upregulated TGF-β, increased the productions of MGO and AGEs, and induced EMT in HMrSV5 cells. High glucose also activated the STAT3 pathway. STAT3 inhibitor reduced the high glucose-induced EMT, via reducing TGF-β expression and repressing the accumulation of MGO and AGEs.Our results revealed a critical role for STAT3 signaling in high glucose-induced EMT in HMrSV5 cells, and suggested that inhibition of STAT3 might be a treatment for high glucose-induced fibrogenesis in PF.
Podocyte injury plays central roles in proteinuria and kidney dysfunction, therefore, identifying specific biomarker to evaluate earlier podocyte injury is highly desirable. Podocyte-secreted angiopoietin-like-4 (Angptl4) mediates proteinuria in different types of podocytopathy. In the present study, we established an experimental minimal change disease (MCD) rat model, induced by adriamycin (ADR) and resulted in definite podocyte injury, to identify the dynamic changes in Angptl4 expression. We also investigated the direct effects of tacrolimus on Angptl4 and podocyte repair. We determined that the glomerular Angptl4 expression was rapidly upregulated and reached a peak earlier than desmin, an injured podocyte marker, in the ADR rats. Furthermore, this upregulation occurred prior to heavy proteinuria and was accompanied by increased urinary Angptl4. We observed that the Angptl4 upregulation occurred only when podocyte was mainly damaged since we didn't observe little Angptl4 upregulation in MsPGN patients. In addition, we observed the glomerular Angptl4 mainly located in injured podocytes rather than normal podocytes. Moreover, we found that tacrolimus treatment significantly promoted podocyte repair and reduced glomerular and urinary Angptl4 expression at an earlier stage with a significant serum Angptl4 upregulation. And similar results were confirmed in MCD patients. In conclusion, this study represents the first investigation to demonstrate that Angptl4 can predict podocyte injury at earlier stages in MCD and the identification of earlier podocyte injury biomarkers could facilitate the prompt diagnosis and treatment of patients with podocytopathy, as well as determination of the prognosis and treatment efficacy in these diseases.
Language is both social phenomenon and cultural phenomenon. Analyzing the popular terms in the aspect of social culture is helpful to recognize the close relationship between language variation and social background. In this way,we can understand the orbit of modern Chinese language development from various angles. It is because of its abundant meaning of social culture which very posses that the term very is becoming popular . That' s to say very embodys social concept, cultural disposition, aesthetic standards and values.
A dynamic relationship exists between transportation and macroeconomic systems during economic development.Evolving transportation system leads to evolution of economic structure,accessibility of transportation facilitates spatial integration of macroeconomy.This paper first presents basic ideas and models of DEA.Transportation and macroeconomy systems were considered as an input-output system,transportation and economic indexes in Zhuhai were applied to the DEA model to analyze the dynamic coordination between transportation and economy.Data indicated that that there was no complete coordination between transportation and economy from 1994 to 2008.It is suggested that Zhuhai should improve the efficiency of transportation to promote further coordination between transportation and macroeconomy.