NFkB plays an important role in controlling biological processes including immune and inflammatory responses, developmental processes, cellular growth, and apoptosis. In response to various stimuli, such as stress, cytokines, free radicals, ultraviolet irradiation, and bacterial or viral antigens, NFkB is activated and translocated from cytokine to the nucleus, where NFkB binds to its response element on the promoter region and regulates a wide spectrum of gene expression. Dysfunction of NFkB activity is associated with cancer, inflammatory and autoimmune disease, and viral infection. Monitoring the NFkB activity is essential to unveil the mechanism of these diseases and conduct drug discovery.
Cells will undergo genotypic changes resulting in reduced responsiveness over time in normal cell culture conditions. Genetic instability is a biological phenomenon that occurs in all stably transfected cells. Therefore, it is critical to prepare an adequate number of frozen stocks at early passages.