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Zhao, H.-Y.

Publications and source records attributed to Zhao, H.-Y..

5 recordsLinked to original sources

Specific Pathogen Free Ten Gene-Edited Pig Donor for Xenotransplantation

Xenotransplantation has entered the clinical phase to fulfill the global organ shortage. However, recent clinical studies revealed that the xenograft from current gene-edited (GE) pigs still poses the risk of immune rejection, and biosafety concerns. In this study, we successfully constructed a large batch of 10- (GTKO/CMAHKO/ {beta}4GalNT2KO/hCD46/hCD55/hCD59/hTBM/hEPCR/hCD39/hCD47) GE cloned (GEC) donor pigs by utilizing gene editing and somatic cell cloning technology, and successfully obtained F1 generation. Phenotypic characterization of 10-GEC pigs showed the deletion of three xenoantigens along with expression of seven human transgenes in various tissues. Digital droplet polymerase chain reaction, and whole genome sequencing indicated 2 copies of hCD46/hCD55/hCD59/hTBM/hCD39 and 1 copy of hEPCR/hCD47 in pig genome without significant off-target and damage to the porcine own functional genes. The validation results showed that 10-GEC pigs effectively inhibited the attacks of human antibodies, complement, and macrophages on porcine endothelial cells and alleviated the coagulation abnormalities between pigs and humans. 10-GEC pigs were negative for all zoonotic pathogens (48) including cytomegalovirus, except streptococcal infections. Kidney, heart, and liver xenografts from these 10-GE pigs were transplanted to non-human primates (NHP), which started working normally without hyperacute rejection. Among them, the heart and liver transplant recipient died without resuscitation due to unexpected interruption of oxygen supply, while the 2 kidney transplant recipients survived for 23 and 16 days, respectively. Pathological analysis showed that 10-GE pig kidney xenografts showed mesenchymal congestion, and fibrosis, cellular hyperplasia, with minor antibody and complement deposition, and significantly reduced the infiltration of CD68+ macrophage. In summary, we successfully produced a group of specific pathogen free GEC donor pigs that effectively mitigated immune rejection upon multi-organ transplantation to NHP.

immunology↗

Production of four-gene (GTKO/hCD55/hTBM/hCD39)-edited donor pigs and kidney xenotransplantation

BackgroundThe number of multigene-modified donor pigs for xenotransplantation is increasing with the advent of gene editing technologies. However, which gene combination is suitable for which organ transplantation remains unclear. MethodsIn this study, we utilized CRISPR/Cas9 gene editing technology, PiggyBac transposon system and somatic cell cloning to construct GTKO/hCD55/hTBM/hCD39 four-gene-edited cloned (GEC) pigs and performed kidney transplantation from pig to rhesus monkey to evaluate the effectiveness of these GEC pigs. ResultsFirst, 107 cell colonies were obtained through drug selection, of which 7 were 4-GE colonies. Two colonies were selected for somatic cell nuclear transfer, resulting in 7 fetuses, of which 4 were GGTA1 biallelic knockout. Both fetuses had higher expression of hCD55, hTBM and hCD39. Therefore, these two fetuses were selected for two consecutive rounds of cloning, resulting in a total of 97 live piglets. After phenotype identification, the GGTA1 gene of these pigs was inactivated, and hCD55, hTBM and hCD39 were expressed in cells and multiple tissues. Furthermore, the numbers of monkey IgM and IgG binding to the peripheral blood mononuclear cells (PBMCs) of the 4-GEC pigs were markedly reduced. Moreover, 4-GEC porcine PBMCs had greater survival rates than those from wild-type pigs through complement-mediated cytolysis assays. In pig-to-monkey kidney xenotransplantation, the kidney xenograft successfully survived for 11 days. All physiological and biochemical indicators were normal, and no hyperacute rejection or coagulation abnormalities were found after transplantation. ConclusionThese results indicate that the GTKO/hCD55/hTBM/hCD39 four-gene modification effectively alleviates immune rejection, and the pig kidney can functionally support the recipient monkeys life.

genetics↗

Production and functional verification of 8-gene (GGTA1, CMAH, β4GalNT2, hCD46, hCD55, hCD59, hTBM, hCD39)-edited donor pigs for xenotransplantation

Gene-edited pig-to-human xenotransplantation continues to make breakthroughs and is expected to enter clinic to solve the global shortage of donor organs. However, which gene combination is suitable for which organ transplantation remains unclear. In this study, we utilized CRISPR/Cas9 gene editing technology, PiggyBac transposon system and somatic cell cloning to construct GTKO/CMAHKO/{beta}4GalNT2KO/hCD46/hCD55/hCD59/hCD39/hTBM 8 gene-edited cloned (GEC) donor pigs, and performed pig to non-human primate (NHP) transplantation to evaluate the effectiveness of these GEC pigs. The multiple vectors were co-transfected into fetal fibroblasts of Diannan miniature pig with O blood type, and 25 colonies were screened out, and one of them carried GGTA1, CMAH and {beta}4GalNT2 biallelic knockout and integration of hCD46, hCD55, hCD59, hTBM and hCD39 genes, which was used as a donor cell for cloning, and a 33-day-old viable fetus was obtained. The fetus was identified and confirmed for normal karyotype and the absence of three xenogeneic antigens -Gal, Neu5Gc and Sda, and expression of hCD46, hCD55, hCD59, hTBM and hCD39 genes, then the recloning was carried out and 28 cloned piglets were obtained by natural delivery. Molecular identification at DNA, mRNA and protein levels showed that 8 gene editing (GE) was successful in these GEC piglets. Moreover, antigen-antibody binding assay and complement-dependent cytotoxicity assay demonstrated that 8GE effectively reduced the immune incompatibility and kidney xenograft survived up to 15 and 17 days into two NHPs, respectively. During this period, the recipient serum antibodies IgA and IgM, complements C3 and C4, coagulation indicators PT, APTT, TT and FIB, as well as most electrolytes and liver function indicators remained relatively stable. The 24-hour urine output and serum creatinine remained normal at a period of post-transplantation. These results indicated that the 8GEC pigs effectively alleviated immune rejection and exerted life-supporting kidney function in the recipient.

genetics↗

Unraveling the impact of hyperleptinemia on female reproduction: Insights from transgenic pig model

BackgroundInfertility is a growing global health concern affecting millions of couples worldwide. Among several factors, an extreme body weight adversely affects reproductive functions. Leptin is a well-known adipokine that serves as an endocrine signal between adiposity and fertility. However, the exact mechanisms underlying the effects of high leptin on female reproduction remain unclear. MethodsTransgenic pig overexpressing leptin (11) were produced by back cross and screened for leptin overexpression, and the growth curve, fat deposition, reproductive performance, apoptosis, serum hormones and cholesterol production, RNA sequencing, and single nucleus RNA sequencing of the leptin-overexpressed pigs and control group were evaluated. ResultsTransgenic pig overexpressing leptin (11) were obtained, which exhibited significantly reduced body weight, body size, and back fat thickness. These pigs manifested late onset of puberty (327{+/-}48.5 vs 150{+/-}6.5 days), irregular estrous behavior characterized by increased inter-estrous interval (28.1{+/-}4.2 vs 21.3 {+/-} 0.9 days), and more numbers of mating until pregnancy (at least 3 times). This reproductive impairment in leptin pigs was related to hormonal imbalances characterized by increased levels of FSH, LH, prolactin, E2, P4, and TSH, altered steroidogenesis such as increased levels of serum CE along with steroidogenic markers (STAR, CYP19A), and ovarian dysfunctions manifested by neutrophilic infiltration and low expression of caspase-3 positive cells on leptin pigs ovary. Meanwhile, bulk RNA sequencing of the ovaries also revealed neutrophilic infiltration followed by upregulation of inflammation-related genes. Further, leptin overexpression triggered immune response, suppressed follicle development and luteinization, imposing metabolism dysfunction and hormone imbalance in the ovary by single-nucleus RNA sequencing (snRNA-seq). ConclusionLow body weight in leptin overexpression pigs adversely affects reproductive performance, causing delayed puberty, irregular estrous cycles, and reduced breeding efficiency. This is linked to metabolic imbalances, increased immune response, and altered ovarian functions. This study provided a theoretical basis for the complex mechanisms underlying leptin, and infertility by employing leptin-overexpressed female pigs.

genetics↗

Extensive Mammalian Germline Genome Engineering

Xenotransplantation, specifically the use of porcine organs for human transplantation, has long been sought after as an alternative for patients suffering from organ failure. However, clinical application of this approach has been impeded by two main hurdles: 1) risk of transmission of porcine endogenous retroviruses (PERVs) and 2) molecular incompatibilities between donor pigs and humans which culminate in rejection of the graft. We previously demonstrated that all 25 copies of the PERV elements in the pig genome could be inactivated and live pigs successfully generated. In this study, we improved the scale of porcine germline editing from targeting a single repetitive locus with CRISPR to engineering 13 different genes using multiple genome engineering methods. we engineered the pig genome at 42 alleles using CRISPR-Cas9 and transposon and produced PERVKO{middle dot}3KO{middle dot}9TG pigs which carry PERV inactivation, xeno-antigen KO and 9 effective human transgenes. The engineered pigs exhibit normal physiology, fertility, and germline transmission of the edited alleles. In vitro assays demonstrated that these pigs gain significant resistance to human humoral and cell mediated damage, and coagulation dysregulations, similar to that of allotransplantation. Successful creation of PERVKO{middle dot}3KO{middle dot}9TG pigs represents a significant step forward towards safe and effective porcine xenotransplantation, which also represents a synthetic biology accomplishment of engineering novel functions in a living organism. One Sentence SummaryExtensive genome engineering is applied to modify pigs for safe and immune compatible organs for human transplantation

synthetic biology↗