Microbiology Immunology a734bee9 All are true about endotoxins except: A Lipopolysaccharides in nature B Circulated in blood C Highly antigenic D Induces IL1 and TNF High-Yield Explanation Ans. C. Highly antigenicEndotoxins are poorly antigenic and cannot be toxoided. Exotoxins are highly antigenic and can be toxoided.