p87 antigen (p87)

The p87 antigen is an 87 kDa N-linked glycoprotein that serves as a key component of the gastrointestinal innate immune system, primarily secreted by Paneth cells in the intestinal crypts (1.2.1, 3.3.1). It was originally identified using the Adnab-9 monoclonal antibody, which was developed against constituents of colorectal adenomas (1.2.3, 3.3.2). The antigen is a significant biomarker for the early detection and prognosis of various conditions, including colorectal adenomas, lung cancer, and Barrett's esophagus, as it is shed into bodily fluids such as stool, sputum, and saliva (1.1.1, 2.1.2). In clinical research, the FERAD ratio—the ratio of serum ferritin to fecal p87—is utilized to assess the activity of the innate immune system and has shown predictive value for survival and susceptibility in diseases like HIV, COVID-19, and chronic fatigue syndrome (1.2.4, 2.2.3, 3.2.4). While its primary role is diagnostic, its expression can be influenced by dietary factors such as folates and turmeric, and the Adnab-9 antibody has been proposed for potential therapeutic applications in cancer (2.1.2, 2.3.4).

Other names

p87 adenoma antigenp87 glycoproteinAdnab-9 antigenPaneth cell p87 product

Adnab-9 is a monoclonal antibody that binds to the p87 antigen for detection and potential therapeutic targeting; folates and turmeric modulate the expression and shedding levels of the antigen (2.1.2, 2.3.4, 3.1.5).