The Chlamydia trachomatis LPS, or lipopolysaccharide, is a major surface component of the pathogen that causes chlamydia infection. This lipid-polysaccharide macromolecule is built onto the outer membrane of the bacterium, providing structural integrity as well as offering some protection from chemicals. Lipopolysaccharides typically induce stress responses from binding with immune cell receptors. Inhibition of C. trachomatis LPS by antibodies and polymyxin B has shown reduced infectivity. Chlamydia LPS has a genus-specific epitope, Kdo trisaccharide, used in immunological detection.