NF-κB p65 is a ubiquitously expressed transcription factor that is a subunit of the NF-κB complex and is encoded by the RELA gene in humans.1 It is composed of an N-terminal Rel homology domain, which mediates dimerization, nuclear localization, and DNA and protein interactions, and two C-terminal transactivation domains that are subject to a variety of post-translational modifications and regulate the transcriptional activity of p65.1,2 NF-κB p65 regulates the expression of a large number of genes in response to inflammatory and environmental cues that play critical roles in innate and adaptive immunity and cellular differentiation.2 Genome-wide deletion of Rela in mice is embryonic lethal.3 Silencing of Rela induces tumor cell apoptosis in a murine Lewis lung carcinoma model, and RELA silencing in THP-1 monocytes decreases secreted levels of IL-1β and TNF-α induced by LPS.4,5 NF-κB p65 is overexpressed in the inflamed joints of patients with rheumatoid arthritis and naïve CD4 T cells isolated from the whole blood of patients with multiple sclerosis have increased phosphorylation of NF-κB p65.6,7 Cayman's NF-κB (p65) (human, recombinant) protein can be used for Western blot and ELISA applications.WARNING This product is not for human or veterinary use.