The C5 Knockout THP-1 Cell Line is a CRISPR/Cas9-mediated C5 knockout derivative of the THP-1 human monocytic leukemia cell line. This cell line provides a stable genetic disruption of the complement component C5 gene, eliminating its expression and allowing researchers to investigate C5-dependent pathways in innate immunity and inflammation. The product is supplied as a validated, antibiotic-free cell culture ready for downstream in vitro applications.
The parental THP-1 cell line, derived from acute monocytic leukemia patient peripheral blood, is a well-established model for studying monocyte and macrophage biology. Following differentiation into macrophage-like cells, THP-1 cells recapitulate key inflammatory responses, including cytokine secretion and complement activation, making them a highly relevant host for examining C5 function in myeloid-driven immune processes.
C5 is a central component of the terminal complement cascade, cleaved by C5 convertase into C5a and C5b. C5a triggers potent pro-inflammatory signals through C5aR1 (CD88), promoting chemotaxis, NLRP3 inflammasome activation, reactive oxygen species production, and the release of IL-6, IL-8, and TNF-??. C5b initiates the sequential assembly of C6, C7, C8, and C9 into the membrane attack complex (MAC), causing cell lysis. C5 expression is regulated by upstream stimuli including LPS, TNF-??, IL-6, and IFN-?? via NF-??B and STAT3 pathways, and its cleavage is modulated by interacting factors such as C3b, complement factor B, complement factor D, and properdin.
Disruption of C5 in THP-1 cells abolishes both C5a signaling and MAC formation, creating a clean loss-of-function model for complement-dependent macrophage responses. This cell line is therefore invaluable for probing how complement dysregulation contributes to diseases like paroxysmal nocturnal hemoglobinuria, atypical hemolytic uremic syndrome, complement-mediated kidney diseases, and age-related macular degeneration, and for testing the specificity of C5-targeted therapeutics.
Research applications include mechanistic studies of complement-mediated inflammation, high-throughput screening of C5 inhibitors or anti-C5 antibodies, and modeling of terminal pathway deficiencies. Standard assays used with this knockout line include C5a ELISA, MAC deposition flow cytometry, C5a-induced chemotaxis assays, cytokine multiplex analysis, and western blotting for pathway validation. This cell line enables detailed functional dissection in a relevant macrophage system. For additional details, please contact Ascent Research.
