SFXN3 Knockout THP-1 Cell Line

The SFXN3 Knockout THP-1 Cell Line is a CRISPR/Cas9-edited knockout cell line designed for functional genomics studies of the SFXN3 gene in a human monocyte model. Utilizing CRISPR/Cas9-mediated gene disruption, this cell line provides a loss-of-function model to investigate the role of SFXN3 in one-carbon metabolism, purine and glutathione synthesis, and mitochondrial serine transport. This product is supplied as a ready-to-use cell line and serves as a valuable tool for researchers in cancer biology, immunometabolism, and mitochondrial biology.

The THP-1 cell line, derived from the peripheral blood of an acute monocytic leukemia patient, is a widely employed monocyte/macrophage model. THP-1 cells exhibit key characteristics of innate immune cells, including robust phagocytic activity, cytokine production, and responsiveness to inflammatory stimuli. Their ability to be differentiated into macrophage-like cells makes them a versatile platform for studying monocyte and macrophage biology, as well as for investigating metabolic reprogramming in the context of immune responses and leukemia pathogenesis.

SFXN3 encodes a mitochondrial serine transporter that channels serine into the mitochondrial matrix, fueling the one-carbon metabolism pathway. Within mitochondria, serine is converted by serine hydroxymethyltransferase 2 (SHMT2) into glycine and a one-carbon unit, which is subsequently processed by methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) and aldehyde dehydrogenase 1 family member L2 (ALDH1L2) to generate formate, purine precursors, and NADPH. SFXN3 activity is regulated by serine availability and by mTORC1 and MYC signaling, and its downstream products??including purine nucleotides, glutathione, and NADPH??are essential for cell proliferation and redox homeostasis. The protein interacts with SHMT2, MTHFD2, and ALDH1L2, forming a functional module that couples mitochondrial serine import to nucleotide and antioxidant synthesis.

In THP-1 monocytes, SFXN3-mediated serine import is critical for sustaining one-carbon metabolism during immune activation and proliferation. Disruption of SFXN3 is predicted to impair formate and purine synthesis, limit glutathione production, and alter NADPH regeneration, potentially compromising antioxidant defenses and cell cycle progression. This knockout model thus enables the dissection of mitochondrial substrate transport and its link to immunometabolic phenotypes, including phagocytosis, cytokine secretion, and inflammatory responses. Moreover, given the THP-1 origin from leukemic cells, the model is particularly relevant for exploring metabolic vulnerabilities in leukemia and other cancers.

The SFXN3 Knockout THP-1 Cell Line is suitable for a broad range of experimental applications, including cancer metabolism studies using LC-MS-based metabolite tracing and Seahorse respirometry to assess mitochondrial function and metabolic flux. Researchers can employ RT-qPCR and western blotting to validate downstream pathway alterations, and flow cytometry or proliferation assays to evaluate immune cell function and growth. This tool supports investigations into one-carbon metabolism, immunometabolism, and mitochondrial substrate transport, and can be used in functional genomics screens. For additional details, please contact Ascent Research.