1.Low-dose rituximab improves progression in early-stage medium-to-high-risk membranous nephropathy:an exploratory study
Qiuyu XU ; Sanxi AI ; Gangan WANG ; Chunyu JIA ; Jiahui WANG ; Ke ZHENG ; Yan QIN ; Gang CHEN ; Xuemei LI
Chinese Journal of Clinical Pharmacology and Therapeutics 2024;29(7):744-751
Membranous nephropathy(MN)is the predominant cause of primary nephrotic syn-drome(NS)among adults.The identification of PLA2R as target antigen has brought about a pro-found transformation in the management of MN,offering a basis for the utilization of B-cell deplet-ing agents such as rituximab(RTX).The question of whether early intervention targeting antibodies can effectively impede the progression of MN,contrib-uting to enhanced disease control and long-term renal outcomes for patients,remains further explo-ration.We analyzed demographic data,laboratory parameters,and renal involvement in 13 patients with PLA2R antibody-related MN who received at least one RTX treatment at our center from Octo-ber 2019 to March 2023.Early-stage medium-to-high-risk MN was defined as baseline or admission anti-PLA2R antibody levels exceeding 50 RU/mL,ex-cluding patients who already presented with ne-phrotic syndrome at baseline.The median duration of MN at the initiation of the first RTX treatment was 4.1 months(IQR 1-7.7),and the median follow-up time after RTX therapy was 27 months(IQR 23-45).All patients had commenced renin-angiotensin system inhibitors before receiving RTX.Following RTX therapy,none of the 13 patients progressed to NS during the follow-up period,and 12 patients achieved complete or partial remission at the 2-year follow-up or the last visit.No deaths,severe infections,or other serious adverse reactions oc-curred during the follow-up period.In conclusion,RTX demonstrates favorable efficacy and safety in early-stage,medium-to-high-risk MN patients.Initi-ating antibody clearance therapy in these patients may be beneficial for long-term disease control and distant renal outcomes.
2.Optimizations of an ELISA-like high-throughput screening assay for the discovery of β-catenin/TCF4 interaction antagonists.
Zhenghao FU ; Gangan YAN ; Xiaohong ZHU ; Xiaoping LIU ; Yunyu CHEN
Chinese Journal of Biotechnology 2021;37(8):2878-2889
In canonical Wnt/β-catenin signaling pathway, β-catenin/TCF4 (T-cell factor 4) interaction plays an important role in the pathogenesis and development of non-small cell lung cancer (NSCLC), and it is tightly associated with the proliferation, chemoresistance, recurrence and metastasis of NSCLC. Therefore, suppressing β-catenin/TCF4 interaction in Wnt/β-catenin signaling pathway would be a new therapeutic avenue against NSCLC metastasis. In this study, considering the principle of enzyme-linked immunosorbent assay (ELISA), an optimized high-throughput screening (HTS) assay was developed for the discovery of β-catenin/TCF4 interaction antagonists. Subsequently, this ELISA-like screening assay was performed using 2 μg/mL GST-TCF4 βBD and 0.5 μg/mL β-catenin, then a high Z' factor of 0.83 was achieved. A pilot screening of a natural product library using this ELISA-like screening assay identified plumbagin as a potential β-catenin/TCF4 interaction antagonist. Plumbagin remarkably inhibited the proliferation of A549, H1299, MCF7 and SW480 cell lines. More importantly, plumbagin significantly suppressed the β-catenin-responsive transcription in TOPFlash assay. In short, this newly developed ELISA-like screening assay will be vital for the rapid screening of novel Wnt inhibitors targeting β-catenin/TCF4 interaction, and this interaction is a potential anticancer target of plumbagin in vitro.
Carcinoma, Non-Small-Cell Lung
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Cell Line, Tumor
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Enzyme-Linked Immunosorbent Assay
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High-Throughput Screening Assays
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Humans
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Lung Neoplasms
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Transcription Factor 4/genetics*
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beta Catenin/genetics*
3.Optimization of expression conditions and determination the proteolytic activity of codon-optimized SARS-CoV-2 main protease in Escherichia coli.
Yunyu CHEN ; Zhenghao FU ; Gangan YAN ; Yuan LIN ; Xiaoping LIU
Chinese Journal of Biotechnology 2021;37(4):1334-1345
The main protease (Mpro) of SARS-CoV-2 is a highly conserved and mutation-resistant coronaviral enzyme, which plays a pivotal role in viral replication, making it an ideal target for the development of novel broad-spectrum anti-coronaviral drugs. In this study, a codon-optimized Mpro gene was cloned into pET-21a and pET-28a expression vectors. The recombinant plasmids were transformed into E. coli Rosetta(DE3) competent cells and the expression conditions were optimized. The highly expressed recombinant proteins, Mpro and Mpro-28, were purified by HisTrapTM chelating column and its proteolytic activity was determined by a fluorescence resonance energy transfer (FRET) assay. The FRET assay showed that Mpro exhibits a desirable proteolytic activity (25 000 U/mg), with Km and kcat values of 11.68 μmol/L and 0.037/s, respectively. The specific activity of Mpro is 25 times that of Mpro-28, a fusion protein carrying a polyhistidine tag at the N and C termini, indicating additional residues at the N terminus of Mpro, but not at the C terminus, are detrimental to its proteolytic activity. The preparation of active SARS-CoV-2 Mpro through codon-optimization strategy might facilitate the development of the rapid screening assays for the discovery of broad-spectrum anti-coronaviral drugs targeting Mpro.
COVID-19
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Codon/genetics*
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Cysteine Endopeptidases/genetics*
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Escherichia coli/genetics*
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Humans
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Peptide Hydrolases
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SARS-CoV-2
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Viral Nonstructural Proteins/genetics*