Diagnosis of chronic Pseudomonas aeruginosa infection in cystic fibrosis by ELISA for anti-pseudomonas LPS IgG antibodies

Abstract

An enzyme-linked immunosorbant assay (ELISA) with urease enzyme was developed with either a polyvalent pseudomonas smooth lipopolysaccharide (LPS) extract vaccine (PEV-02) or rough LPS (R-LPS) from P. aeruginosa rough mutant PAC605. Each ELISA was able to differentiate between sera from cystic fibrosis (CF) patients chronically colonized with P. aeruginosa and sera from non-colonized patients. Sera from non-colonized and intermittently colonized CF patients seldom reacted with any of the Pseudomonas LPS, whereas sera from chronically colonized CF patients reacted strongly with most of the sixteen smooth O-serotype vaccine components and with the PAC605 R-LPS, indicating the presence either of a number of different serotype specific IgG antibodies and/or IgG antibodies directed to a common antigenic component of LPS rough core. Absorption studies and immunoblot analysis demonstrated that in sera from CF patients who were chronically colonized with P. aeruginosa a significant component of the anti- P. aeruginosa antibodies is specific for the core of P. aeruginosa LPS and cross reactive with a number of serotypes of P. aeruginosa LPS.