The TGFB1 gene encodes transforming growth factor β1 (TGF-β1), a member of the TGF-β superfamily and a multifunctional secreted cytokine. It participates in a variety of physiological and pathological processes by precisely regulating cell proliferation, differentiation, apoptosis, and the synthesis and deposition of the extracellular matrix (ECM). TGF-β1 plays a critical regulatory role in maintaining embryonic development, wound healing, tissue homeostasis, angiogenesis, extracellular matrix remodeling, skeletal development, and immune system balance ^[1]. This cytokine is widely expressed in multiple tissues and cell types, with relatively high expression levels in the spleen, bone marrow, platelets, and smooth muscle tissues. Its expression is enhanced or enriched in platelets, megakaryocytes, fibroblasts, and immune cells (such as eosinophils and T cells) ^[2]. Studies have shown that aberrant expression of the TGFB1 gene is closely associated with the occurrence and progression of various human diseases, including fibrosis, inflammation, tumors, and Camurati-Engelmann disease (characterized by bone hyperostosis) ^[3]. It serves as an important therapeutic target in the fields of oncology, fibrotic diseases, and autoimmune disorders. Dysregulation of the TGF-β signaling pathway is closely linked to multiple cancers, in which the loss of TGF-β-mediated growth inhibitory function represents a key mechanism underlying the tumorigenesis of colorectal cancer, pancreatic cancer, and others. Meanwhile, in the tumor microenvironment, TGF-β1 acts as a potent immunosuppressive cytokine that participates in the co-regulation of immune checkpoint expression, thereby promoting tumor immune evasion ^[4-5]. As a core pro-fibrotic cytokine, TGF-β1 drives the fibrotic process in multiple organs, including the liver, lung, and kidney, through mechanisms such as activating fibroblasts or myofibroblasts, promoting ECM deposition and remodeling, and inhibiting ECM degradation ^[6-7]. Furthermore, TGF-β1 plays a central protective role in autoimmune diseases; its expression deficiency, secretion impairment, receptor signaling defects, or cell-type-specific functional loss can all lead to disruption of immune tolerance and drive the onset and progression of autoimmune diseases ^[8-9]. The huTGFB1 mouse is a humanized model constructed using gene editing technology. The sequence from the start codon to downstream of the mouse Tgfb1 3' UTR was replaced with the sequence from the start codon to downstream of the human TGFB1 3' UTR. The huTGFB1 mice can be utilized to investigate the development and progression of TGF-β1-mediated diseases, including tumors, fibrosis, and autoimmune disorders. This model facilitates the research and development of TGFB1-targeted therapeutics and supports preclinical pharmacological and pharmacodynamic evaluations.

Ndufs1 is located on chromosome 1 of mice. SgRNA and ssDNA were designed using Nuclease Technology; Ndufs1 conditional knockout mice were obtained by high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.

Gucy1b2 is located on chromosome 14 of mice. Nuclease Technology will be used to design sgRNA; Gucy1b2 knockout mice will be obtained by applying high-throughput electroporation of fertilized eggs. After sexual maturity, sperm were collected for cryopreservation.