CD20 is a surface marker protein of B-cell lymphoma, and its extracellular region is the target of specific antibodies and drugs. To obtain a cheap and easily modified specific preparation targeting CD20, we optimized the gene of CD20 extracellular region according to codon degeneracy to facilitate its expression in Escherichia coli. The optimized gene was cloned into pGEX-4T-1 vector, and the recombinant vector was transformed into E. coli BL21(DE3) for expression. The purified protein was identified by SDS-PAGE and Western blotting. Systematic evolution of ligands by exponential enrichment (SELEX) was employed to screen the ssDNA aptamer that specifically binds to the fusion protein, and the affinity of the aptamer to CD20 was detected by flow cytometry. Then, the cytotoxicity test was carried out to examine the inhibitory effect of the aptamer on B lymphoma cells. In this study, we established the prokaryotic expression method of CD20 and obtained the aptamer specifically binding to the extracellular region of CD20, which laid a foundation for the development of therapeutic drugs targeting CD20.
Humans ; Escherichia coli/metabolism* ; SELEX Aptamer Technique/methods* ; Aptamers, Nucleotide/genetics* ; Antigens, CD20/metabolism* ; Ligands

Neuronomodulation refers to the modulation of neural conduction and synaptic transmission (i.e., the conduction process involved in synaptic transmission) of excitable neurons via changes in the membrane potential in response to chemical substances, from spillover neurotransmitters to paracrine or endocrine hormones circulating in the blood. Neuronomodulation can be direct or indirect, depending on the transduction pathways from the ligand binding site to the ion pore, either on the same molecule, i.e. the ion channel, or through an intermediate step on different molecules. The major players in direct neuronomodulation are ligand-gated or voltage-gated ion channels. The key process of direct neuronomodulation is the binding and chemoactivation of ligand-gated or voltage-gated ion channels, either orthosterically or allosterically, by various ligands. Indirect neuronomodulation involves metabotropic receptor-mediated slow potentials, where steroid hormones, cytokines, and chemokines can implement these actions. Elucidating neuronomodulation is of great significance for understanding the physiological mechanisms of brain function, and the occurrence and treatment of diseases.
Ligands ; Neurons/metabolism* ; Synaptic Transmission/physiology* ; Ion Channels/metabolism* ; Hormones/metabolism*

We identified distinct senescence-related molecular subtypes and critical genes among prostate cancer (PCa) patients undergoing radical prostatectomy (RP) or radical radiotherapy (RT). We conducted all analyses using R software and its suitable packages. Twelve genes, namely, secreted frizzled-related protein 4 (SFRP4), DNA topoisomerase II alpha (TOP2A), pleiotrophin (PTN), family with sequence similarity 107 member A (FAM107A), C-X-C motif chemokine ligand 14 (CXCL14), prostate androgen-regulated mucin-like protein 1 (PARM1), leucine zipper protein 2 (LUZP2), cluster of differentiation 38 (CD38), cartilage oligomeric matrix protein (COMP), vestigial-like family member 3 (VGLL3), apolipoprotein E (APOE), and aldehyde dehydrogenase 2 family member (ALDH2), were eventually used to subtype PCa patients from The Cancer Genome Atlas (TCGA) database and GSE116918, and the molecular subtypes showed good correlations with clinical features. In terms of the tumor immune environment (TME) analysis, compared with cluster 1, cancer-associated fibroblasts (CAFs) scored significantly higher, while endothelial cells scored lower in cluster 2 in TCGA database. There was a statistically significant correlation between both CAFs and endothelial cells with biochemical recurrence (BCR)-free survival for PCa patients undergoing RP. For the GSE116918 database, cluster 2 had significantly lower levels of CAFs and tumor purity and higher levels of stromal, immune, and Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) scores than cluster 1; in addition, patients with high levels of CAFs, stromal scores, immune scores, and ESTIMATE scores and low levels of tumor purity tended to suffer from BCR. Based on the median of differentially expressed checkpoints, high expression of CD96, hepatitis A virus cellular receptor 2 (HAVCR2), and neuropilin 1 (NRP1) in GSE116918 and high expression of CD160 and tumor necrosis factor (ligand) superfamily member 18 (TNFSF18) in TCGA database were associated with a significantly higher risk of BCR than their counterparts. In conclusion, we first constructed distinct molecular subtypes and critical genes for PCa patients undergoing RP or RT from the fresh perspective of senescence.
Male ; Humans ; Endothelial Cells ; Ligands ; Prostatic Neoplasms/pathology* ; Prostate/pathology* ; Prostatectomy ; Aldehyde Dehydrogenase, Mitochondrial ; DNA-Binding Proteins ; Transcription Factors

OBJECTIVES: To study the expression levels of CD4⁺NKG2D⁺ T cells and NKG2D soluble ligands, the soluble MHC class I chain-related molecules A and B (sMICA/sMICB) in the active stage and stable stage of juvenile idiopathic arthritis (JIA) and their role in the disease activity of JIA. METHODS: Nineteen children with systemic JIA and 20 children with articular JIA who were diagnosed in Children's Hospital of Chongqing Medical University from November 2019 to December 2021 were enrolled in this prospective study. Six healthy children were enrolled as the control group. After peripheral blood samples were collected, ELISA was used to measure the levels of sMICA and sMICB, and flow cytometry was used to measure the percentage of CD4⁺NKG2D⁺ T cells. Systemic Juvenile Arthritis Disease Activity Score-27 (sJADAS-27)/Juvenile Arthritis Disease Activity Score-27 (JADAS-27) was used to evaluate the disease activity in children with JIA. The Pearson correlation analysis and the receiver operating characteristic (ROC) curve were used to assess the role of CD4⁺NKG2D⁺ T cells, sMICA and sMICB in the disease activity of JIA. RESULTS: The active systemic JIA and active articular JIA groups had a significant increase in the percentage of CD4⁺NKG2D⁺ T cells compared with the control group and their corresponding inactive JIA group (P<0.05). The JIA groups had significantly higher levels of sMICA and sMICB than the control group (P<0.05), and the active articular JIA group had a significantly higher level of sMICB than the stable articular JIA group (P<0.05). In the children with JIA, the percentage of CD4⁺NKG2D⁺ T cells and the levels of sMICA and sMICB were positively correlated with sJADAS-27/JADAS-27 disease activity scores (P<0.05). The ROC curve analysis showed that sMICB had an area under the curve of 0.755 in evaluating the disease activity of JIA, with a specificity of 0.90 and a sensitivity of 0.64. CONCLUSIONS The percentage of CD4⁺NKG2D⁺ T cells and the levels of sMICA and sMICB increase in children with JIA compared with healthy children and are positively correlated with the disease activity of JIA, suggesting that CD4⁺NKG2D⁺ T cells and NKG2D ligands can be used as potential biomarkers for evaluating the disease activity of JIA.
Child ; Humans ; Arthritis, Juvenile/pathology* ; Ligands ; NK Cell Lectin-Like Receptor Subfamily K ; Prospective Studies ; T-Lymphocytes/pathology*

Proto-Oncogene Proteins c-akt/metabolism* ; Butyrates ; Ligands ; Glucose ; Receptors, G-Protein-Coupled/metabolism* ; Glycogen Synthase Kinases/metabolism* ; Glycogen Synthase Kinase 3 beta ; Phosphorylation

The development of chronic liver disease can be promoted by excessive fat accumulation, dysbiosis, viral infections and persistent inflammatory responses, which can lead to liver inflammation, fibrosis and carcinogenesis. An in-depth understanding of the etiology leading to chronic liver disease and the underlying mechanisms influencing its development can help identify potential therapeutic targets for targeted treatment. Orphan nuclear receptors (ONRs) are receptors that have no corresponding endogenous ligands to bind to them. The study of these ONRs and their biological properties has facilitated the development of synthetic ligands, which are important for investigating the effective targets for the treatment of a wide range of diseases. In recent years, it has been found that ONRs are essential for maintaining normal liver function and their dysfunction can affect a variety of liver diseases. ONRs can influence pathophysiological activities such as liver lipid metabolism, inflammatory response and cancer cell proliferation by regulating hormones/transcription factors and affecting the biological clock, oxidative stress, etc. This review focuses on the regulation of ONRs, mainly including retinoid related orphan nuclear receptors (RORs), pregnane X receptor (PXR), leukocyte cell derived chemotaxin 2 (LECT2), Nur77, and hepatocyte nuclear factor 4α (HNF4α), on the development of different types of chronic liver diseases in different ways, in order to provide useful references for the therapeutic strategies of chronic liver diseases based on the regulation of ONRs.
Humans ; Orphan Nuclear Receptors/metabolism* ; Receptors, Steroid/physiology* ; Ligands ; Liver ; Liver Diseases ; Intercellular Signaling Peptides and Proteins

Proteolysis targeting chimera (PROTAC) refers to heterobifunctional small molecules that can simultaneously bind an E3 ubiquitin ligase and a target protein, enabling specific degradation of the target protein with the aid of the ubiquitin proteasome system. At present, most PROTAC drugs are in the clinical trial stage, and the ligands are mainly non-covalent compounds. PROTAC drugs have the advantage of overcoming drug resistance and degrading "undruggable" target proteins, but non-covalent ligands could lead to the hook effect that undermines drug efficacy. With its own advantages, covalent ligands can avoid the occurrence of this phenomenon, which is of great help to the development of PROTAC. This review summarizes the progress in preclinical and clinical research and application of PROTAC molecules targeting three different classes of protein targets, including intranuclear, transmembrane, and cytosolic proteins. We also offer perspective discussions to provide research ideas and references for the future development of PROTAC.
Proteolysis ; Proteolysis Targeting Chimera ; Proteasome Endopeptidase Complex/metabolism* ; Ubiquitin-Protein Ligases/metabolism* ; Proteins/metabolism* ; Ligands

In this study, the authors cloned a glycosyltransferase gene PpUGT2 from Paris polyphylla var. yunnanensis with the ORF length of 1 773 bp and encoding 590 amino acids. The phylogenetic tree revealed that PpUGT2 belonged to the UGT80A subfamily and was named as UGT80A49 by the UDP-glycosyltransferase(UGT) Nomenclature Committee. The expression vector pET28a-PpUGT2 was constructed, and enzyme catalytic reaction in vitro was conducted via inducing protein expression and extraction. With UDP-glucose as sugar donor and diosgenin and pennogenin as substrates, the protein was found with the ability to catalyze the C-3 hydroxyl β-glycosylation of diosgenin and pennogenin. To further explore its catalytic characteristic, 15 substrates including steroids and triterpenes were selected and PpUGT2 showed its activity towards the C-17 position of sterol testosterone with UDP-glucose as sugar donor. Homology modelling and molecule docking of PpUGT2 with substrates predicted the key residues interacting with ligands. The re-levant residues of PpUGT2-ligand binding model were scanned to calculate the corresponding mutants, and the optimized mutants were obtained according to the changes in binding affinity of the ligand with protein and the surrounding residues within 5.0 Å of ligands, which had reference value for design of the mutants. This study laid a foundation for further exploring the biosynthetic pathway of polyphyllin as well as the structure of sterol glycosyltransferases.
Ligands ; Glycosyltransferases/genetics* ; Sterols ; Phylogeny ; Ascomycota ; Liliaceae/chemistry* ; Melanthiaceae ; Diosgenin ; Sugars ; Glucose ; Uridine Diphosphate

OBJECTIVES: This study aims to investigate the genome-wide DNA methylation and transcriptome expression profiles of peripheral blood mononuclear cells (PBMCs) in patients with systemic sclerosis (SSc) with interstitial lung disease (ILD), and to analyze the effects of DNA methylation on Wnt/β-catenin and chemokine signaling pathways. METHODS: PBMCs were collected from 19 patients with SSc (SSc group) and 18 healthy persons (control group). Among SSc patients, there were 10 patients with ILD (SSc with ILD subgroup) and 9 patients without ILD (SSc without ILD subgroup). The genome-wide DNA methylation and gene expression level were analyzed by using Illumina 450K methylation chip and Illumina HT-12 v4.0 gene expression profiling chip. The effect of DNA methylation on Wnt/β-catenin and chemokine signal pathways was investigated. RESULTS: Genome-wide DNA methylation analysis identified 71 hypermethylated CpG sites and 98 hypomethylated CpG sites in the SSc with ILD subgroup compared with the SSc without ILD subgroup. Transcriptome analysis distinguished 164 upregulated genes and 191 downregulated genes in the SSc with ILD subgroup as compared with the SSc without ILD subgroup. In PBMCs of the SSc group, 35 genes in Wnt/β-catenin signaling pathway were hypomethylated, while frizzled-1 (FZD1), mitogen-activated protein kinase 9 (MAPK9), mothers against DPP homolog 2 (SMAD2), transcription factor 7-like 2 (TCF7L2), and wingless-type MMTV integration site family, member 5B (WNT5B) mRNA expressions were upregulated as compared with the control group (all P<0.05). Compared with the SSc without ILD subgroup, the mRNA expressions of dickkopf homolog 2 (DKK2), FZD1, MAPK9 were upregulated in the SSc with ILD subgroup, but the differences were not statistically significant (all P>0.05). In PBMCs of the SSc group, 38 genes in chemokine signaling pathway were hypomethylated, while β-arrestin 1 (ARRB1), C-X-C motif chemokine ligand 10 (CXCL10), C-X-C motif chemokine ligand 16 (CXCL16), FGR, and neutrophil cytosolic factor 1C (NCF1C) mRNA expressions were upregulated as compared with the control group (all P<0.05). Compared with the SSc without ILD subgroup, the mRNA expressions of ARRB1, CXCL10, CXCL16 were upregulated in the SSc with ILD subgroup, but the differences were not statistically significant (all P>0.05). CONCLUSIONS There are differences in DNA methylation and transcriptome profiles between SSc with ILD and SSc without ILD. The expression levels of multiple genes in Wnt/β- catenin and chemokine signaling pathways are upregulated, which might be associatea with the pathogenesis of SSc.
Humans ; DNA Methylation ; Transcriptome ; beta Catenin ; Leukocytes, Mononuclear ; Ligands ; DNA ; RNA, Messenger/genetics*

OBJECTIVE: To compare the consistency of programmed cell death 1-ligand 1 (PD-L1, clone E1L3N, 22C3, SP263) in different immunohistochemical staining methods. METHODS: The first step was to select the optimal process: The PD-L1(clone E1L3N) antibody recommended process, self-built process ①, self-built process ② and self-built process ③ were used to perform immunohistochemical staining in 5 cases of tonsil tissue. The quality of all slides was scored by expert pathologists (0-6 points). The process with the highest score was selected. The second step was to compare the consistency between the optimal procedure and the two standard procedures. Thirty-two cases of lung non-small cell carcinoma diagnosed by pathology in Peking University First Hospital in the past two years were randomly selected. The 32 cases were stained in parallel with the SP263 and 22C3 standard procedures, and all stained slides were scored by specialized pathologists for tumor proportion score (TPS). The scoring results were grouped according to < 1%, ≥1% to < 10%, ≥10% to < 50%, and ≥50%. The consistency of PD-L1 detection antibody clone E1L3N and 22C3, E1L3N and SP263 staining results was analyzed. RESULTS: Tonsil stained slides scores (0-6 points) were as follows: The recommended protocol was 5, 5, 5, 5 and 5. The self-built process ① was 5, 6, 6, 5 and 6. The self-built process ② was 4, 4, 4, 4 and 4.The self-built process ③ was 3, 3, 3, 3 and 3. The self-built process ① was the best with the highest score. The TPSs of 32 non small cell lung carcinoma (NSCLC) cases were as follows: Of self-built process ①, 6 cases were lower than 1%, 5 cases were from 1% to 10%, 10 cases were from 10% to 50%, and 11 cases were higher than 50%; of 22C3 standard procedure, 5 cases were lower than 1%, 3 cases were from 1% to 10%, 13 cases were from 10% to 50%, 11 cases were higher than 50%; of SP263 standard procedure, 7 cases were lower than 1%, 4 cases were from 1% to 10%, 11 cases were from 10% to 50%, 10 cases were higher than 50%. The results of the consistency test were as follows: The κ value for self-built process ① and 22C3 standard procedure was 0.736 (P < 0.001), the agreement was good; the κ value for self-built process ① and SP263 standard procedure was 0.914 (P < 0.001), the agreement was very good. CONCLUSION The immunostaining using PD-L1(E1L3N) with validated self-built staining protocol ① by Ventana Benchmark GX platform can obtain high quality of slides, and the TPSs based on these slides are in good agreement with 22C3 and SP263 standard procedures.
Humans ; Carcinoma, Non-Small-Cell Lung ; Lung Neoplasms/pathology* ; Immunohistochemistry ; B7-H1 Antigen/metabolism* ; Ligands ; Antibodies ; Staining and Labeling ; Apoptosis