The MYC oncogene family comprises regulatory genes and proto-oncogenes that encode transcription factors, involved in various cellular processes such as the cell cycle, apoptosis, DNA repair, and metabolism. Members include c-Myc (MYC), l-Myc (MYCL), and n-Myc (MYCN). c-Myc (MYC) is a basic helix-loop-helix leucine zipper (bHLHZip) transcription factor, which forms heterodimers with Max protein to bind DNA and regulate the expression of approximately 15% of genes, thereby participating in key cellular processes such as cell proliferation, apoptosis, DNA repair, and metabolism. In many cancers, c-Myc is overexpressed, leading to uncontrolled cell proliferation and tumor growth, such as in Burkitt's lymphoma where c-Myc gene rearrangement is common. Dysregulation of the MYC oncogene plays a crucial role in tumorigenesis, predominantly through transcriptional dysregulation resulting in overexpression of c-Myc protein. Alb-Cre+/MYC+ mice are generated by crossing H11-CAG-LSL-hMYC-IRES-EGFP mice (Catalog Number: C001338), which conditionally express the human c-Myc oncogene, with Alb-Cre mice that express Cre recombinase specifically in hepatocytes under the control of the Alb promoter. The Cre-mediated recombination results in the deletion of the transcriptional stop sequence (Loxp-Stop-Loxp, LSL) in H11-CAG-LSL-hMYC-IRES-EGFP mice, leading to overexpression of the MYC oncogene in the liver and subsequent carcinogenesis. This model, therefore, spontaneously develops liver cancer with an early onset.

Inhibin βE subunit (INHBE) is a member of the transforming growth factor-β (TGF-β) superfamily, highly specifically expressed in liver cells. The precursor protein of INHBE generates the inhibin β subunit after proteolytic processing. This protein is associated with various cellular processes, including cell proliferation, apoptosis, immune response, and hormone secretion. During the development of obesity and diabetes, the expression of INHBE protein inhibits the proliferation and growth of relevant cells in the pancreas and liver. Research has found a positive correlation between INHBE expression in the liver and insulin resistance and body mass index (BMI), suggesting that INHBE may be a liver factor in altering systemic metabolic status under conditions of obesity-related insulin resistance ^[1]. The studies conducted by Alnylam Pharmaceuticals and the Regeneron Genetics Center (RGC), respectively, revealed the close relationship between INHBE and fat regulation. The research demonstrated that rare loss-of-function variants in INHBE may protect the liver from the impact of inflammation, abnormal blood lipids, and type 2 diabetes by promoting healthy fat storage. Patients carrying such mutations exhibit more normal fat distribution, significantly reduced abdominal fat, improved metabolic conditions, and a decreased risk of cardiovascular diseases and type 2 diabetes ^[2-4]. These findings suggest that INHBE is a liver-specific negative regulator of fat storage. Inhibiting the expression of INHBE genes and proteins may be a potential strategy for treating metabolic disorders related to improper fat distribution and storage. Consequently, several small nucleic acid pharmaceutical companies, including Alnylam Pharmaceuticals, Arrowhead Pharmaceuticals, and Wave Life Sciences, are currently developing RNA interference (RNAi) drugs targeting INHBE to treat conditions such as obesity ^[5-7]. RNAi drugs primarily include small interfering RNA (siRNA) and antisense oligonucleotides (ASO). siRNA targets and degrades specific mRNA, while ASO binds to the target mRNA, preventing its translation or inducing its degradation, thereby inhibiting the expression of the target gene. Considering the genetic differences between humans and animals, humanizing mouse genes can accelerate the clinical development of RNAi therapies targeting human INHBE. This strain is a mouse Inhbe gene humanized model and can be used to study therapies targeting INHBE for obesity. The homozygous B6-huINHBE mice are viable and fertile. In addition, based on the independently developed TurboKnockout fusion BAC recombination technology, Cyagen can also generate hot mutation models based on this strain and provide customized services for specific mutations to meet the experimental needs in pharmacology and other fields.

Interleukin 17A (IL-17A) is a signature cytokine of the T helper 17 (Th17) subset of CD4+ T cells and one of the six members (IL-17A~IL-17F) of the IL-17 family. IL-17A is primarily produced by Th17 cells and can also be produced by other immune cells under certain conditions, including CD8+ T cells, γδT cells, natural killer T (NKT) cells, monocytes, neutrophils, and microglia ^[1]. IL-17A mediates downstream pathways that induce the production of inflammatory molecules, chemokines, antimicrobial peptides, and remodeling proteins, which have important effects on host defense, cell transport, immune regulation, and tissue repair, especially in inducing innate immune defense. In healthy skin, commensal microorganisms induce the production of IL-17A to provide antifungal protection. When the skin barrier is damaged, IL-17A promotes epithelial cell proliferation and can clear pathogenic factors, promoting tissue repair and wound healing ^[2]. IL-17A usually protects the body when it is acutely injured, but when a wound requires long-term healing and becomes a chronic injury, the role of IL-17A may transform into wound erosion or excessive proliferation, ultimately leading to loss of function ^[3]. IL-17A plays a key role in various infectious diseases, inflammations, autoimmune diseases, and cancers. Its high expression level is associated with chronic inflammatory diseases such as rheumatoid arthritis, psoriasis, and multiple sclerosis. Lung injury caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is largely the result of the promotion of inflammatory reactions by cytokines such as IL-17A. Dysregulation of IL-17 signaling promotes pathogenic inflammation. IL-17A has a pathogenic role in mediating the important inflammatory pathway of psoriasis. The IL-23/Th17/IL-17A pathway is a key link in its pathogenesis, and inhibiting the expression of IL-17A can effectively alleviate psoriasis ^[4]. IL-17A is also associated with the course of ankylosing spondylitis (AS), and IL-17A inhibitors can effectively treat AS ^[5]. In addition, studies have shown that IL-17A is involved in the pathogenesis of neurodegenerative diseases in the central nervous system, and its expression level is related to the severity and progression of the disease ^[3]. The IL17F gene, located on chromosome 6p12.2, is primarily expressed by activated T cells, particularly Th17 cells, as well as other immune cells like γδ T cells and some innate immune cells ^[6]. The gene encodes the interleukin-17F (IL-17F) cytokine, a disulfide-linked homodimer protein that shares significant sequence homology with IL-17A ^[7]. Functionally, IL-17F is a pro-inflammatory cytokine that binds to the IL-17RA/RC receptor complex, triggering downstream signaling pathways involving Act1 and TRAF6, leading to the induction of various cytokines (like IL-6, IL-8, GM-CSF) and chemokines, which contribute to neutrophil recruitment and inflammation in barrier tissues such as the skin, lungs, and gut ^[8]. Elevated levels or dysregulation of IL-17F have been implicated in the pathogenesis of several autoimmune and inflammatory diseases, including psoriasis, rheumatoid arthritis, inflammatory bowel disease (like Crohn's disease and ulcerative colitis), and potentially Sjögren's syndrome, highlighting its role in chronic inflammatory processes ^[7-9]. The B6-huIL17A/huIL17F mouse is a dual-gene humanized model constructed by gene-editing technology. Based on the B6-hIL-17A mouse (catalog number: C001510), the sequences from the ATG start codon to the TGA stop codon of the endogenous mouse Il17f gene were replaced with the sequences from the ATG start codon to the TAA stop codon of the human IL17F gene. This model can be used for research on the pathogenesis of various chronic inflammatory diseases, such as rheumatoid arthritis (RA), psoriasis, multiple sclerosis, and inflammatory bowel diseases (IBD) and the related therapeutic drugs, as well as for the development of IL17A/IL17F-targeted drugs.

Interleukin 17A (IL-17A) is a signature cytokine of the T helper 17 (Th17) subset of CD4+ T cells and one of the six members (IL-17A~IL-17F) of the IL-17 family. IL-17A is primarily produced by Th17 cells and can also be produced by other immune cells under certain conditions, including CD8+ T cells, γδT cells, natural killer T (NKT) cells, monocytes, neutrophils, and microglia ^[1]. IL-17A mediates downstream pathways that induce the production of inflammatory molecules, chemokines, antimicrobial peptides, and remodeling proteins, which have important effects on host defense, cell transport, immune regulation, and tissue repair, especially in inducing innate immune defense. In healthy skin, commensal microorganisms induce the production of IL-17A to provide antifungal protection. When the skin barrier is damaged, IL-17A promotes epithelial cell proliferation and can clear pathogenic factors, promoting tissue repair and wound healing ^[2]. IL-17A usually protects the body when it is acutely injured, but when a wound requires long-term healing and becomes a chronic injury, the role of IL-17A may transform into wound erosion or excessive proliferation, ultimately leading to loss of function ^[3]. IL-17A plays a key role in various infectious diseases, inflammations, autoimmune diseases, and cancers. Its high expression level is associated with chronic inflammatory diseases such as rheumatoid arthritis, psoriasis, and multiple sclerosis. Lung injury caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is largely the result of the promotion of inflammatory reactions by cytokines such as IL-17A. Dysregulation of IL-17 signaling promotes pathogenic inflammation. IL-17A has a pathogenic role in mediating the important inflammatory pathway of psoriasis. The IL-23/Th17/IL-17A pathway is a key link in its pathogenesis, and inhibiting the expression of IL-17A can effectively alleviate psoriasis ^[4]. IL-17A is also associated with the course of ankylosing spondylitis (AS), and IL-17A inhibitors can effectively treat AS ^[5]. In addition, studies have shown that IL-17A is involved in the pathogenesis of neurodegenerative diseases in the central nervous system, and its expression level is related to the severity and progression of the disease ^[3]. B6-hIL-17A mice are humanized mouse models that express human IL-17A protein. They were constructed by using gene editing technology to replace the sequence encoding the endogenous extracellular domain of the mouse Il17a gene with the corresponding sequence from the human IL17A gene while retaining the mouse signal peptide. This strain can be used for mechanism research and preclinical evaluation of therapeutic drugs for various chronic inflammatory diseases such as rheumatoid arthritis, psoriasis, and multiple sclerosis. The homozygotes are viable and fertile.

The FGFR1 gene provides instructions for the synthesis of the fibroblast growth factor receptor 1, a member of the receptor tyrosine kinase (RTK) family. This protein is characterized by an extracellular region with three immunoglobulin-like domains for ligand binding, a single transmembrane segment, and an intracellular tyrosine kinase domain that triggers downstream signaling cascades like the MAPK/ERK and PI3K/AKT pathways. FGFR1 is widely expressed across diverse tissues, with particularly high levels in the developing mesoderm, skeletal system, and the central nervous system, where it is essential for the migration of gonadotropin-releasing hormone (GnRH) neurons and olfactory bulb development ^[1]. Functionally, it acts as a master regulator of cell proliferation, differentiation, and survival, playing a pivotal role in embryonic limb induction and adult tissue homeostasis ^[2]. Mutations or chromosomal aberrations in FGFR1 are linked to a diverse array of diseases: gain-of-function mutations cause craniosynostosis syndromes like Pfeiffer and Jackson-Weiss syndromes, while loss-of-function variants lead to Kallmann syndrome (characterized by delayed puberty and an absent sense of smell) ^[3]. Additionally, FGFR1 gene amplifications and rearrangements are significant oncogenic drivers in various cancers, including squamous cell lung cancer, certain breast cancers, and 8p11 myeloproliferative syndrome ^[4]. The B6-huFGFR1 mouse is a humanized model constructed through gene-editing technology, in which the mouse Fgfr1 endogenous extracellular domain genomic DNA is replaced with the human FGFR1 extracellular domain genomic DNA. This model can be used for research on craniosynostosis syndromes, Kallmann syndrome, and various cancers, as well as for screening, development, and preclinical evaluation of FGFR1-targeted therapeutics.

The IL15 gene encodes a pleiotropic four-α-helix bundle cytokine known as Interleukin-15 (IL-15), which is essential for the development, survival, and activation of immune cells, particularly Natural Killer (NK) cells and memory CD8+ T cells. Unlike many cytokines, IL-15 is primarily regulated at the post-transcriptional and translational levels rather than just transcriptionally, and it is uniquely delivered to target cells through trans-presentation, where it is shuttled to the cell surface bound to its high-affinity receptor, IL-15Rα ^[1]. The protein is widely expressed across a variety of tissues, including the placenta, skeletal muscle, kidney, lung, and heart, and is produced by both hematopoietic cells (such as monocytes, macrophages, and dendritic cells) and non-hematopoietic cells (such as epithelial cells and fibroblasts) ^[2]. Functionally, IL-15 triggers the JAK/STAT (specifically JAK1/3 and STAT3/5) and PI3K/AKT/mTOR signaling pathways to promote cellular proliferation and inhibit apoptosis by upregulating anti-apoptotic factors like BCL2 ^[3]. Because of its potent inflammatory effects, dysregulation of the IL15 gene is implicated in several pathologies: over-expression is strongly associated with autoimmune diseases like Celiac disease, Rheumatoid Arthritis, and Multiple Sclerosis, as well as certain malignancies like Adult T-cell Leukemia, while its deficiency can lead to severe immunodeficiency or impaired response to viral infections ^[4]. The B6-huIL15 mouse is a humanized model constructed through gene-editing technology, in which the region from partial intron 4 to TGA stop codon of mouse Il15 is replaced with the region from partial intron 4 to TGA stop codon of human IL15. This model can be used for research on autoimmune diseases like Celiac disease, Rheumatoid Arthritis, and Multiple Sclerosis, as well as certain malignancies like Adult T-cell Leukemia. Furthermore, it serves as a platform for the screening, development, and preclinical evaluation of IL15-targeted therapeutics.

TNF-like ligand 1A (TL1A), also known as TNF superfamily member 15 (TNFSF15), is a member of the tumor necrosis factor (TNF) family encoded by the TNFSF15 gene in humans. TL1A acts as a ligand for death receptor 3 (DR3) and decoy receptor 3 (DcR3), providing a stimulatory signal for downstream pathways. It regulates the proliferation, activation, and apoptosis of effector cells, as well as cytokine and chemokine production. TL1A is expressed in various immune cells, including monocytes, macrophages, dendritic cells, and T cells, as well as in non-immune cells such as synovial fibroblasts and endothelial cells. It plays a crucial role in modulating immune responses by promoting the differentiation and survival of T cells, particularly Th17 cells involved in inflammatory processes ^[1]. TL1A enhances IL-2 responses in anti-CD3/CD28-stimulated T cells and synergizes with IL-12 and IL-18 to augment IFN-γ release in human T and NK cells, biasing T cell differentiation toward a Th1 phenotype ^[2]. Dysregulation of TL1A expression is implicated in autoimmune diseases, including inflammatory bowel disease (IBD), rheumatoid arthritis (RA), primary biliary cholangitis (PBC), systemic lupus erythematosus (SLE), and ankylosing spondylitis (AS) ^[1]. TL1A has emerged as a promising therapeutic target, with ongoing research focused on developing monoclonal antibodies and other biologics to neutralize TL1A and reduce inflammation in autoimmune disorders. Clinical trial results suggest that TL1A inhibition can be used in the treatment of various autoimmune diseases, particularly IBD ^[3-5]. The B6-hTL1A(TNFSF15) mouse is a humanized model constructed by replacing the mouse Tnfsf15 gene in situ with the human TNFSF15 gene using gene editing technology, in which the mouse Tnfsf15 endogenous extracellular domain will be replaced with the human TNFSF15 extracellular domain. The homozygous B6-hTL1A(TNFSF15) mice are viable and fertile, and can be used for studies on T cell differentiation and survival, immune response regulation, and pathogenesis of autoimmune diseases, as well as for TL1A-targeted drug development.

Neonatal Fc receptor (FcRn) is a cell surface receptor protein that binds to the Fc region of IgG antibodies. It is structurally similar to MHC class I molecules and comprises an α-chain and β2-microglobulin (β2M). The α-chain of the FcRn receptor is encoded by the Fcγ receptor and transporter (FCGRT) gene, while β2-microglobulin is encoded by the β-2-microglobulin (B2M) gene. FcRn is expressed widely on epithelial cells, endothelial cells, and hematopoietic cells, and is found in various tissues and organs, including the intestine, placenta, kidney, and liver ^[1-2]. IgG antibodies are the most abundant immunoglobulins in human serum (about 75%), and play an important role in the immune response by defending against pathogens and toxins. Compared to other immunoglobulins, IgG has a high circulating level, a longer half-life, and the ability to be transferred from mother to offspring. These properties are closely related to its interaction with FcRn. FcRn binds to the Fc region of IgG, preventing IgG molecules from being degraded by lysosomes. This prolongs the in vivo half-life of IgG and is involved in the transport, maintenance, and distribution metabolism of IgG. In addition, the specific transport process of IgG from the mother to the fetus to provide the fetus with short-term passive immunity is also mediated by FcRn ^[1-2]. In addition to its protective role, IgG autoantibodies are also associated with many pathological conditions. Therefore, novel FcRn blocking therapies are an effective strategy to reduce the circulating levels of pathogenic IgG autoantibodies and to reduce IgG-mediated diseases. In addition, many drugs also utilize FcRn's protective mechanism for IgG by fusing or conjugating with the Fc portion of IgG to prolong its serum half-life and improve its pharmacokinetics. The FCGRT gene encodes the α-chain of the FcRn protein, and its homologous genes are present in most mammals. This model is a humanized FcRn mouse, in which the sequence encoding the extracellular domain of the endogenous protein in the mouse Fcgrt gene has been replaced by the corresponding sequence in the human FCGRT gene. B6-hFcRn(Extra) mice are therefore useful for in vivo studies of IgG, screening of IgG antibody drug candidates, and evaluating the pharmacology, efficacy, and pharmacokinetics of drugs. The homozygous mice are viable and fertile.

The IL31RA gene encodes the interleukin-31 receptor subunit alpha, a type I cytokine receptor that serves as a critical mediator in neuroimmune communication. The protein typically functions as a heterodimer by associating with the oncostatin M receptor (OSMRβ) to form the functional IL-31 receptor complex, which triggers intracellular signaling through the JAK/STAT (primarily STAT3), PI3K/AKT, and MAPK pathways ^[1]. While the gene is expressed at low levels across various tissues, including the testis, thymus, and bone marrow, it is highly localized and functionally significant in CD14+ monocytes, macrophages, keratinocytes, and a specific subset of dorsal root ganglia (DRG) neurons. In these tissues, IL31RA plays a pivotal role in mediating pruritus (itching) and regulating skin immunity and inflammation ^[2]. Genetically, dysregulation of the IL31RA pathway is heavily implicated in the pathogenesis of inflammatory and pruritic diseases such as atopic dermatitis, prurigo nodularis, allergic asthma, and certain cutaneous T-cell lymphomas, making it a major therapeutic target for monoclonal antibodies like nemolizumab ^[3]. The B6-hIL31RA mouse is a humanized model constructed through gene-editing technology, in which the sequences from aa.19 to partial intron 4 of mouse Il31ra were deleted, and the human IL31RA extracellular domain-mouse Il31ra transmembrane-cytoplasmic domain-3’UTR of mouse Il31ra WPRE-BGH pA cassette was inserted downstream of mouse Il31ra signal peptide. This model can be used for research on inflammatory and pruritic diseases such as atopic dermatitis, prurigo nodularis, allergic asthma, and certain cutaneous T-cell lymphomas, as well as for screening, development, and preclinical evaluation of IL31RA-targeted therapeutics.

The SLC16A1 gene encodes the Monocarboxylate Transporter 1 (MCT1) protein, a vital proton-coupled symporter that facilitates the rapid transmembrane movement of metabolic substrates, including lactate, pyruvate, and ketone bodies (acetoacetate and β-hydroxybutyrate). This gene is ubiquitously expressed across nearly all human tissues to maintain energy balance and pH homeostasis, with notably high levels labeled in the heart, oxidative skeletal muscle fibers, erythrocytes (red blood cells), and the brain (specifically in oligodendrocytes and the blood-brain barrier), while being uniquely "disallowed" or suppressed in normal pancreatic beta-cells to prevent inappropriate insulin release ^[1]. Functionally, MCT1 is central to the "lactate shuttle" mechanism, allowing tissues to coordinate metabolic fuel exchange by facilitating either the influx or efflux of substrates depending on the concentration gradient and proton motive force ^[2]. Mutations in SLC16A1 are clinically linked to Erythrocyte Lactate Transporter Defect, which causes exercise-induced muscle cramping and fatigue, and Monocarboxylate Transporter 1 Deficiency, a rare disorder characterized by recurrent episodes of severe ketoacidosis and vomiting triggered by fasting or infection ^[3]. Conversely, gain-of-function mutations in the gene's promoter lead to familial hyperinsulinemia type 7 (HHF7), where exercise triggers excessive insulin secretion, while its widespread overexpression in various cancers (such as melanoma and lung cancer) supports the Warburg effect by managing lactate efflux to prevent intracellular acidification and fueling tumor progression ^[4]. The B6-huSLC16A1 mouse is a humanized model constructed through gene-editing technology, in which the sequences from the ATG start codon to the TGA stop codon of the endogenous mouse Slc16a1 gene are replaced with the sequences from the ATG start codon to the TGA stop codon of the human SLC16A1 gene. This model can be used for research on diseases such as Erythrocyte Lactate Transporter Defect, Monocarboxylate Transporter 1 Deficiency, familial hyperinsulinemia type 7 (HHF7), and various cancers, as well as for screening, development, and preclinical evaluation of SLC16A1-targeted therapeutics.