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+/hMYC-IRES-EGFP+ 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.

The Transferrin receptor (TFRC) gene encodes Transferrin Receptor 1 (TFR1), a protein that is expressed at low levels in most normal cells but shows increased expression in highly proliferative cells, such as basal epidermal cells, intestinal epithelium, and certain activated immune cells. Brain capillary endothelial cells, which constitute the blood-brain barrier (BBB), also express this receptor at high levels ^[1]. TFR1 plays a critical role in maintaining iron metabolism and homeostasis by facilitating receptor-mediated endocytosis of iron-bound transferrin (Tf) via Tf cycling, thereby promoting iron uptake ^[2]. Cellular iron deficiency can lead to apoptosis, while cellular transformation requires substantial iron to sustain proliferation, with iron overload contributing to tumor progression. The high expression of TFR1 in many tumors makes it a potential tumor marker, offering a target for therapies to inhibit tumor growth and metastasis ^[1]. Moreover, TFR1 is implicated in anemia and iron metabolism disorders. Studies have shown that elevated TFR1 expression in cardiomyocytes is associated with exacerbated inflammation in myocarditis patients ^[3]. The tau protein, a microtubule-associated protein encoded by MAPT, is primarily localized to neuronal axons and plays a critical role in microtubule stability and assembly. By binding to microtubules, the tau protein helps to maintain neuronal cell shape. Mutations in MAPT can promote tau aggregation, leading to pathological tau protein accumulation and death of glutamatergic cortical neurons ^[4]. Additionally, certain MAPT mutations can affect pre-mRNA exon splicing, altering the ratio of 3R to 4R tau protein isoforms and increasing the relative production of 4R-tau protein, which is more prone to fibril formation ^[5]. The B6-hTFRC/htau mice are a model expressing human TFRC protein and tau protein, generated by crossing B6-hTFRC(CDS) mice (Catalog No.: C001584) with B6-htau mice (Catalog No.: C001410). These mice can be used for research on neurodegenerative diseases and iron metabolism disorders, as well as for the development and preclinical evaluation of TFRC/MAPT-targeted therapeutic agents.

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 Cryopyrin protein, encoded by the NOD-like receptor family pyrin domain-containing 3 (NLRP3) gene, is a core component of the inflammasome in the innate immune system. As a member of the NOD-like receptor (NLR) family, NLRP3 is predominantly expressed in leukocytes and chondrocytes. It participates in the host defense against damage and infection by recognizing pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs) to activate immune responses ^[6]. In its inactive monomeric state, NLRP3 senses intracellular damage signals, such as abnormal protein aggregates and lipid accumulation. Upon activation, NLRP3 oligomerizes, adopting an active conformation and assembling into inflammasome complexes, subsequently activating Caspase-1 to drive the maturation and secretion of pro-inflammatory cytokines, including IL-1β and IL-18 ^[6-7]. Activated NLRP3 not only induces the release of inflammatory cytokines but also triggers lytic cell pyroptosis. The intracellular components released during pyroptosis can further amplify inflammatory signals, forming a positive feedback loop of autoinflammation. Moreover, IL-1β can exacerbate the inflammatory cascade by stimulating the production of inflammatory markers such as IL-6 and high-sensitivity C-reactive protein (hsCRP) ^[8-9]. Given NLRP3's upstream position relative to IL-1β/IL-18 and other inflammatory factors, targeting its activity can effectively block the self-reinforcing mechanism of chronic inflammation, providing a significant therapeutic strategy for inflammation-related diseases ^[10]. The potential therapeutic areas include Alzheimer’s disease, Parkinson’s disease (via neuroinflammation modulation), inflammatory bowel disease, metabolic dysfunction-associated steatohepatitis (MASH), gout, and obesity-related metabolic inflammation ^[11-12]. B6-hTL1A/hNLRP3 mice are TL1A and NLRP3 double humanized mouse models obtained by mating TL1A humanized mouse models (Catalog No. C001603) with NLRP3 humanized mouse models (Catalog No. C001616). B6-hTL1A/hNLRP3 mice express human TL1A and NLRP3 genomic sequences under the control of mouse promoters. This model is capable of reproducing human TL1A and NLRP3 and is a valuable tool for studying autoimmune diseases and inflammation-related diseases. In addition, this model also provides a powerful preclinical research platform for evaluating the efficacy and mechanism of therapeutic drugs targeting TL1A and NLRP3.

The Transferrin receptor (TFRC) gene encodes Transferrin Receptor 1 (TFR1), a protein that is expressed at low levels in most normal cells but shows increased expression in highly proliferative cells, such as basal epidermal cells, intestinal epithelium, and certain activated immune cells. Brain capillary endothelial cells, which constitute the blood-brain barrier (BBB), also express this receptor at high levels ^[1]. TFR1 plays a critical role in maintaining iron metabolism and homeostasis by facilitating receptor-mediated endocytosis of iron-bound transferrin (Tf) via Tf cycling, thereby promoting iron uptake ^[2]. Cellular iron deficiency can lead to apoptosis, while cellular transformation requires substantial iron to sustain proliferation, with iron overload contributing to tumor progression. The high expression of TFR1 in many tumors makes it a potential tumor marker, offering a target for therapies to inhibit tumor growth and metastasis ^[1]. Moreover, TFR1 is implicated in anemia and iron metabolism disorders. Studies have shown that elevated TFR1 expression in cardiomyocytes is associated with exacerbated inflammation in myocarditis patients ^[3]. As a target for antibody-mediated cancer therapy, TFR1 can be leveraged through two approaches: one involves the use of antibodies conjugated to anti-cancer drugs, which are indirectly internalized via receptor-mediated endocytosis; the other employs antibodies that directly disrupt receptor function or induce Fc effector functions such as antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), or complement-dependent cytotoxicity (CDC). Various clinical drugs targeting TFR1 are currently under development, including antisense oligonucleotides (ASOs), antibody-drug conjugates (ADCs), and antibody-oligonucleotide conjugates, applicable to diseases such as cancer, anemia, and neurodegenerative disorders. Research indicates that enhancing antibody transport across the blood-brain barrier via TFR1, by forming specific bispecific antibodies with anti-β-amyloid antibodies, can improve therapeutic outcomes in Alzheimer's patients ^[4-5]. As research progresses, TFR1 is expected to become an effective clinical target for multiple diseases and a synergistic target for drug delivery across the blood-brain barrier (BBB). The tau protein, a microtubule-associated protein encoded by MAPT, is primarily localized to neuronal axons and plays a critical role in microtubule stability and assembly. By binding to microtubules, the tau protein helps to maintain neuronal cell shape. Mutations in MAPT can promote tau aggregation, leading to pathological tau protein accumulation and death of glutamatergic cortical neurons ^[6]. Additionally, certain MAPT mutations can affect pre-mRNA exon splicing, altering the ratio of 3R to 4R tau protein isoforms and increasing the relative production of 4R-tau protein, which is more prone to fibril formation ^[7-8]. The B6-huTFRC/htau mouse is a dual-gene humanized model obtained by mating B6-huTFRC mice (catalog number: C001860) with B6-htau mice (catalog number: C001410). This model can be used for research on neurodegenerative diseases and iron metabolism diseases, as well as pre-clinical studies of TFRC/MAPT-targeted therapeutic drugs.

The B6-Uox KO/huXDH mice are humanized disease models obtained by mating Uox KO mice (catalog No.: C001232) with B6-huXDH mice (catalog No.: C001586). This model is suitable for studying the pathological mechanisms of hyperuricemia and gout, and provides an ideal preclinical research platform for the development of novel xanthine oxidase inhibitors and small nucleic acid therapies. It is worth noting that heterozygous Uox KO mice can survive and are fertile, while homozygous Uox KO mice require drugs such as Allopurinol to maintain their survival after birth.

The B6-huTFRC/huACVR2B mouse is a dual-gene humanized model obtained by mating B6-huTFRC mice (catalog No.: C001860) with B6-huACVR2B mice (catalog No.: C001904). This model can be used in the research of muscle atrophy and growth regulation, tumorigenesis and development, reproduction and gonadal function, iron metabolism diseases, and neurodegenerative diseases, and it helps with the development of TFRC/ACVR2B-targeted drugs and preclinical pharmacological and efficacy evaluations.