polygalacturonic-acid and Scrub-Typhus

In the Weil-Felix test, sera from patients infected with Orientia tsutsugamushi reacted with lipopolysaccharide (LPS) from Proteus mirabilis OXK strains. The O-polysaccharide of P. mirabilis OXK LPS consisted of pentasaccharide repeating units, with amidically-linked lysine residues. The lysine, linked to galacturonic residues, which plays an important role in the reaction with rabbit anti-OXK antibodies, was revealed with the aid of synthetic antigens. Using ELISA, immunoglobulin M antibodies from scrub typhus patients reacted with the O-specific polysaccharide of strain OXK LPS only. This reaction was inhibited by rabbit antibodies specific to the O-antigen of strain OXK LPS. Both human and rabbit antibodies may bind to similar epitopes on the O-polysaccharide part of P. mirabilis OXK LPS.

Topics: Acrylic Resins; Animals; Antibodies, Bacterial; Antibody Specificity; Carbohydrate Sequence; Cross Reactions; Enzyme-Linked Immunosorbent Assay; Epitopes; Haptens; Hemolytic Plaque Technique; Hexuronic Acids; Humans; Immunoglobulin M; Lysine; Molecular Sequence Data; O Antigens; Orientia tsutsugamushi; Proteus mirabilis; Rabbits; Scrub Typhus