Serum amyloid A (SAA) is the most prominent acute-phase protein in vertebrates and its role in innate immunity has been reviewed. SAA functions are located on special regions of SAA, which are highly conserved in all vertebrates. 1. The discovery of the acute-phase nature of SAA before its existence was known by experimental murine AA amyloidosis induced by septic conditions. 2. Identification of the amyloid substance and its precursor. 3. SAA changes its conformation and antigenic presentation when it is separated from HDL during the acute phase. Febrile temperatures activate SAA through the separation from HDL. There is a temperature-specific gradual separation of SAA isotypes or groups of isotypes from HDL. 4. Generic monoclonal AA antibodies mc4 and mc29 assist in elucidating selected SAAs’ vital functions (as in defense, platelet functions, female propagation and others). 5. In a murine sepsis model, the monoclonals mc4 and mc29 can cause early death while the intact SAA can prevent this. Through this, a checkpoint (“stop and go”) for survival was discovered. Generic monoclonals can also identify the life-saving structures of SAA’s vital functions and those of other acute-phase proteins. This principle is essential for the production of novel drugs against sepsis and other innate-related diseases. 6. Some remarks follow.
Part of the book: Infectious Process and Sepsis