Detection of antibodies to Pseudomonas aeruginosa in serum and oral fluid from patients with cystic fibrosis

Abstract

Cystic fibrosis (CF) patients who are chronically infected with Pseudomonas aeruginosa make serum antibodies to bacterial surface LPS as well as other pseudomonas antigens. This study investigated the feasibility of using oral fluid samples for the detection of pseudomonas antibodies in CF patients and compared these results with corresponding serum antibodies. Most strains of P. aeruginosa produce two forms of LPS molecule, termed A-band (described as a common antigen) and B-band (O-serotype-specific antigen), apparently bound to a common core oligosaccharide moiety. A-band LPS was demonstrated in 45 out of 49 clinical isolates of P. aeruginosa by SDS-PAGE and immunoblotting with a specific antibody. Oral fluids were collected from 17 adult CF patients, all of whom were sputum culture positive for P. aeruginosa (13 also provided serum samples), 11 primary ciliary dyskinesia (PCD) patients and 37 healthy volunteers. Antibodies to A-band LPS were detected by immunoblotting in all of the CF patients' oral fluids but 10 of the volunteer samples gave weak reactions with immunoblotting. Six of the PCD patients gave a weak reaction with A-band antibodies and only one demonstrated antibodies to core LPS. In a quantitative ELISA, 15 of the 17 CF patients' oral fluids were shown to contain antibodies to A-band LPS, whilst none of the volunteer samples contained antibodies to A-band LPS. All serum samples from the CF patients were positive by both methods. Thus this is a sensitive procedure for the detection of antibodies to A-band LPS of P. aeruginosa in oral fluid and serum from patients with CF.

Genetic and Functional Diversity of Pseudomonas aeruginosa Lipopolysaccharide

“…The strains that did not react to the mAb belong to serotypes O7, O12, O13, O14, O15, and O16 (Lam et al, 1989; Currie et al, 1995). However, a majority of clinical P. aeruginosa isolates examined since then were found to be devoid of OSA but produce CPA as the predominant surface polysaccharide antigen (Lam et al, 1989; Weisner et al, 2007). In a separate study, CPA was found to be a receptor for bacteriophage A7, indicating its significance as a cell-surface polysaccharide component of P. aeruginosa and its role in the co-evolution with temperate bacteriophages (Rivera et al, 1992).…”

Single-Nucleotide Polymorphisms Found in the migA and wbpX Glycosyltransferase Genes Account for the Intrinsic Lipopolysaccharide Defects Exhibited by Pseudomonas aeruginosa PA14

“…The strains that did not react to the MAb were of serotypes O7, O12, O13, O14, O15, and O16 (19,20). It is worth noting that the majority of clinical P. aeruginosa isolates from chronically infected cystic fibrosis patients lack OSA but produce CPA as the predominant surface polysaccharide antigen (19,21). CPA biosynthesis genes are organized into two contiguous clusters, an eight-gene operon consisting of rmd, gmd, wbpW, wzm, wzt, wbpX, wbpY, and wpbZ (pa5454-pa5449) (22)(23)(24) and a newly identified, five-gene operon, pa5455-pa5459, in PAO1 (25) (Fig.…”

Pseudomonas aeruginosa infection in patients with cystic fibrosis: scientific evidence regarding clinical impact, diagnosis, and treatment

“…Another group of authors, seeking to establish whether it would be possible to use saliva as a tool for the detection of anti-P. aeruginosa antibodies in patients with CF and in normal individuals,( 29 ) described significant titers in the oral fluids from 15 of the 17 patients with CF but in none from the healthy volunteers (LE 2b).…”

“…Outro grupo de autores procurou avaliar se seria possível utilizar a saliva como um instrumento de detecção de anticorpos anti- P. aeruginosa em pacientes com FC e em indivíduos normais,( 29 ) descrevendo títulos significativos nos fluidos orais de 15 dos 17 pacientes com FC, mas em nenhum dos voluntários sadios (NE 2b).…”