Flagelin 22 is primarily used in immunological research and vaccine development due to its role as a potent immunostimulant. It is often employed as an adjuvant to enhance the immune response to vaccines, particularly in the development of vaccines targeting bacterial infections. Additionally, Flagelin 22 is utilized in studies focused on understanding the innate immune system, as it can activate toll-like receptor 5 (TLR5), a key component in the body's defense mechanism against pathogens. Its ability to trigger strong immune responses makes it valuable in both therapeutic and experimental settings aimed at improving immune system modulation and efficacy.