Objective To explore the construction of α-1,3-galactosyltransferase (GGTA1) gene-knockout (GTKO) Diannan miniature pigs and the kidney xenotransplantation from pigs to rhesus macaques, and to assess the effectiveness of GTKO pigs. Methods The GTKO Diannan miniature pigs were constructed using the CRISPR/Cas9 gene-editing system and somatic cell cloning technology. The phenotype of GTKO pigs was verified through polymerase chain reaction, Sanger sequencing and immunofluorescence staining. Flow cytometry was used to detect antigen-antibody (IgM) binding and complement-dependent cytotoxicity. Kidney xenotransplantation was performed from GTKO pigs to rhesus macaques. The humoral immunity, cellular immunity, coagulation and physiological indicators of the recipient monkeys were monitored. The function and pathological changes of the transplanted kidneys were analyzed using ultrasonography, hematoxylin-eosin staining, immunohistochemical staining and immunofluorescence staining. Results Single-guide RNA (sgRNA) targeting exon 4 of the GGTA1 gene in Diannan miniature pigs was designed. The pGL3-GGTA1-sgRNA1-GFP vector was transfected into fetal fibroblasts of Diannan miniature pigs. After puromycin selection, two cell clones, C59# and C89#, were identified as GGTA1 gene-knockout clones. These clones were expanded to form cell lines, which were used as donor cells for somatic cell nuclear transfer. The reconstructed embryos were transferred into the oviducts of trihybrid surrogate sows, resulting in 13 fetal pigs. Among them, fetuses F04 and F11 exhibited biallelic mutations in the GGTA1 gene, and F04 had a normal karyotype. Using this GTKO fetal pig for recloning and transferring the reconstructed embryos into the oviducts of trihybrid surrogate sows, seven surviving piglets were obtained, all of which did not express α-Gal epitope. The binding of IgM from the serum of rhesus monkey 20# to GTKO pig PBMC was reduced, and the survival rate of GTKO pig PBMC in the complement-dependent cytotoxicity assay was higher than that of wild-type pig. GTKO pig kidneys were harvested and perfused until completely white. After the left kidney of the recipient monkey was removed, the pig kidney was heterotopically transplanted. Following vascular anastomosis and blood flow restoration, the pig kidney rapidly turned pink without hyperacute rejection (HAR). Urine appeared in the ureter 6 minutes later, indicating successful kidney transplantation. The right kidney of the recipient was then removed. Seven days after transplantation, the transplanted kidney had good blood flow, the recipient monkey's serum creatinine level was stable, and serum potassium and cystatin C levels were effectively controlled, although they increased 10 days after transplantation. Seven days after transplantation, the levels of white blood cells, lymphocytes, monocytes and eosinophils in the recipient monkey increased, while platelet count and fibrinogen levels decreased. The activated partial thromboplastin time, thrombin time and prothrombin time remained relatively stable but later showed an upward trend. The recipient monkey survived for 10 days. At autopsy, the transplanted kidney was found to be congested, swollen and necrotic, with a small amount of IgG deposition in the renal tissue, and a large amount of IgM, complement C3c and C4d deposition, as well as CD68⁺ macrophage infiltration. Conclusions The kidneys of GTKO Diannan miniature pigs may maintain normal renal function for a certain period in rhesus macaques and effectively overcome HAR, confirming the effectiveness of GTKO pigs for xenotransplantation.

Objective To develop GTKO (α-1,3-galactosyltransferase gene-knockout, GTKO)/hCD55 (human CD55) gene-edited xenotransplant donor pigs and verify their function. Methods In this study, CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated nuclease 9), PiggyBac transposon technology and somatic cell nuclear transfer technology were used to construct GTKO/hCD55 gene-edited Diannan miniature pigs. The phenotype and function of GTKO/hCD55 pigs were analyzed by Sanger sequencing, real-time fluorescence quantitative PCR, flow cytometry, immunofluorescence, bisulfite sequencing, antigen-antibody binding assays, and complement-dependent cytotoxicity assays. Results After transfection of PX458 and PiggyBac gene editing vectors into wild-type fetal pig fibroblasts, 48 single-cell colonies were obtained through puromycin drug screening. Two single-cell colonies were selected for somatic cell nuclear transfer, resulting in two fetal pigs at 33 days of gestation. The GGTA1(α-1,3-galactosyltransferase) genotypes of fetal pig F01 were -17 bp and wild type (WT), while the GGTA1 genotypes of fetal pig F02 were -26 bp/+2 bp and -3 bp. The hCD55 mRNA expression levels of both fetal pigs were significantly higher than those of WT pigs (P＜0.01). The fetal pig F02 was selected as the donor cell source for recloning, 11 surviving piglets were obtained, all identified as GTKO/hCD55 gene-edited pigs. These pigs showed absence of α-Gal antigen expression, but weak or no expression of hCD55 was observed. Methylation analysis of the hCD55 gene's CpG island showed hypermethylation in kidney tissue lacking hCD55 expression, whereas it was not methylated or partially methylated in kidney tissue expressing hCD55. Moreover, codon optimization of the CpG island of the hCD55 gene to reduce CG content could achieve stable expression of the hCD55 gene. In addition, antigen-antibody binding experiment showed that the amount of human IgM binding to GTKO/hCD55 gene-edited pig fibroblasts was significantly lower than that of WT pigs (P＜0.01). Complement-dependent cytotoxicity experiment showed that the survival rate of fibroblasts in GTKO/hCD55 pigs was significantly higher than that in WT pigs (P＜0.01). Conclusion This study demonstrates the successful generation of GTKO/hCD55 gene-edited xenotransplant donor pigs. Methylation-induced gene silencing of the hCD55 gene can be effectively avoided by reducing the CG content of the CpG island through codon optimization. This study provides a reference for the development of xenotransplant donor pigs and guides subsequent research on xenotransplantation.

Objective To explore the effects of combined exposure to bisphenol A (BPA) and high-fat diet on liver lipid metabolism and hepatocyte senescence in mice, and to elucidate the potential mechanisms of the onset and development of non-alcoholic fatty liver disease (NAFLD). Methods Specific pathogen free C57BL/6J mice were randomly divided into six groups, with 10 mice with equal numbers of each sex in each group. The mice in the control group and the simple BPA group were fed with regular diet, while others four groups of mice were fed with high-fat diet. At the same time, the mice in the simple BPA group were intragastric administered with BPA at a dose of 50 μg/kg body weight, while the mice in the low-, medium- and high-dose BPA+high-fat groups were intragastric administered with BPA at doses of 5, 50 and 500 μg/kg body weight respectively. The mice in the control group and the high-fat group were intragastric administered with the same volume of corn oil once per day for 90 consecutive days. Liver tissues were subjected to hematoxylin-eosin (HE) and Oil Red O staining. Liver coefficients and lipid-stained area ratios were calculated. Serum level of total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, and the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined using an automatic biochemical analyzer. The hepatic tumor necrosis factor-α (TNF-α), interleukin (IL)-6, and IL-10 levels were quantified by enzyme-linked immunosorbent assay. The relative expression of cholesterol regulatory element binding protein 1 (SREBP1), CCAAT enhancer binding protein α, P16, and phosphorylated histone H2AX (γ-H2AX) in liver tissues was detected using Western blotting. The interaction effect of the combined exposure to BPA and high-fat diet was observed based on the result of mice in the control group, the simple high-fat group, the simple BPA group, and the medium-dose BPA group+high-fat group (the combined exposure group) using a 2×2 factorial design. The results of mice in the simple high-fat group and the low-, medium-, and high-dose BPA+high-fat groups were used to observe the effect of BPA exposure dose under high-fat diet conditions. Results i) The interactive effect of combined exposure to BPA and high fat. The HE and Oil Red O staining results indicated that the combined exposure to BPA and high-fat diet successfully established NAFLD in mice. The interactive effect of combined exposure to BPA and high-fat diet on serum ALT activity and the relative expression of P16 in the liver tissue of female mice, as well as the serum ALT and AST activities and the relative expression of SREBP1 in the liver tissue of male mice was significant (all P<0.05). Specifically, the serum ALT activity of male mice in the combined exposure group was higher than that in the simple high-fat group (P<0.05), while the ALT activity in the serum of female mice in the combined exposure group was lower than that in the simple BPA group (P<0.05). The relative expression of SREBP1 protein in the liver tissue of male mice in the combined exposure group was higher than that in the control group, the simple high-fat group, and the simple BPA group (all P<0.05). For the other indicators, there were no significant differences in the interactive effect of combined exposure to BPA and high-fat diet (all P>0.05). ii) Dose effects of BPA exposure. The HE and Oil Red O staining result showed that the degree of vacuolar steatosis in the liver of female and male mice of medium- and high-dose BPA + high-fat groups was aggravated, and the range of inflammatory cell infiltration was expanded when compared with same-sex mice in the simple high-fat group. The serum ALT activity and the fat stained area ratio, as well as the relative expression of P16 in liver tissue of female mice in high-dose BPA + high-fat group increased (all P<0.05), while the level of IL-10 in liver tissue decreased (P<0.05), compared with the female mice in simple high-fat group. The serum ALT activity, the TNF-α level in liver tissue, and the relative expression of SREBP1, P16 and γ-H2AX proteins in liver tissue of male mice in high-dose BPA + high-fat group increased (all P<0.05), while the IL-6 level in liver tissue decreased (P<0.05), compared with the male mice in simple high-fat group. For the female or male mice in the low- and medium-dose BPA + high-fat groups, only some of the above indicators showed significant changes (all P<0.05). Conclusion The combined exposure to BPA and high-fat diet has a synergistic effect on the onset and development of NAFLD. The mechanism may be related to inducing cellular senescence and modulation of lipid synthesis pathways, thereby affecting liver steatosis. The exposure dose of BPA may affect the synergistic effect.

Background and Objectives: RUNX2 plays an essential role during the odontoblast differentiation of dental pulp stem cells (DPSCs). RUNX2 Exon 5 is an alternative exon and essential for RUNX2 transcriptional activity. This study aimed to investigate the regulatory mechanisms of RUNX2 exon 5 alternative splicing in human DPSCs. Methods: and Results: The regulatory motifs of RUNX2 exon 5 were analyzed using the online SpliceAid program. The alternative splicing of RUNX2 exon 5 in DPSCs during mineralization-induced differentiation was analyzed by RT-PCR. To explore the effect of splicing factor YBX1 on exon 5 alternative splicing, gaining or losing function of YBX1 was performed by transfection of YBX1 overexpression plasmid or anti-YBX1 siRNA in DPSCs. Human RUNX2 exon 5 is evolutionarily conserved and alternatively spliced in DPSCs. There are three potential YBX1 binding motifs in RUNX2 exon 5. The inclusion of RUNX2 exon 5 and YBX1 expression level increased significantly during mineralization-induced differentiation in DPSCs. Overexpression of YBX1 significantly increased the inclusion of RUNX2 exon 5 in DPSCs. In contrast, silence of YBX1 significantly reduced the inclusion of exon 5 and the corresponding RUNX2 protein expression level. Knockdown of YBX1 reduced the expression of alkaline phosphatase (ALP) and osteocalcin (OC) and the mineralization ability of DPSCs, while overexpression of YBX1 increased the expression of ALP and OC and the mineralization ability of DPSCs. Conclusions Human RUNX2 exon 5 is conserved evolutionarily and alternatively spliced in DPSCs. Splicing factor YBX1 promotes the inclusion of RUNX2 exon 5 and improves the mineralization ability of DPSCs.

Coronavirus disease 2019(COVID-19),which is caused by SARS-CoV-2,varies with regard to symptoms and mortality rates among populations.Humoral immunity plays critical roles in SARS-CoV-2 infection and recovery from COVID-19.However,differences in immune responses and clinical features among COVID-19 patients remain largely unknown.Here,we report a database for COVID-19-specific IgG/IgM immune responses and clinical parameters(named COVID-ONE-hi).COVID-ONE-hi is based on the data that contain the IgG/IgM responses to 24 full-length/truncated proteins corresponding to 20 of 28 known SARS-CoV-2 proteins and 199 spike protein peptides against 2360 serum samples collected from 783 COVID-19 patients.In addition,96 clinical parameters for the 2360 serum samples and basic information for the 783 patients are integrated into the database.Furthermore,COVID-ONE-hi provides a dashboard for defining samples and a one-click analysis pipeline for a single group or paired groups.A set of samples of interest is easily defined by adjusting the scale bars of a variety of parameters.After the"START"button is clicked,one can readily obtain a comprehensive analysis report for further interpretation.COVID-ONE-hi is freely available at www.COVID-ONE.cn.

Objective To investigate the value of intravoxel incoherent motion MR imaging (IVIM-MRI)on monitoring impairment of renal function in hydronephrosis.Methods Left hydronephrosis model of Healthy New-Zealand rabbits made by ureteral incomplete obstruction were scanned by IVIM-MRI at 4, 8, 12, and 16 weeks.The change of IVIM-MRI quantitative parameters (ADC values, D values, D* values, and f values) in left hydronephrosis kidney were observed.The correlation between these parameters and glomerular filtration rate (GFR) were evaluated.Results ADC values, D values, D* values and f values at cortex and medulla in left hydronephrosis model of rabbits decreased gradually in the progression of renal damage after 4, 8, 12, and 16 weeks.For D value, f value and ADC values, there was statistical significant difference among the group of 12 weeks, the group of 16 weeks, the control group, and the group of 4 weeks;statistical significant difference was also observed between the group of 8 weeks and the group of 16 weeks by LSD contrast.ADC values, D values, D* values, and f values were positively correlated to GFR at 4, 8, 12, and 16 weeks for left hydronephrosis model of rabbits.Conclusion IVIM-MRI could monitor impairment of renal function in hydronephrosis dynamically.