Production and characterisation of mouse monoclonal antibodies reacting with the lipopolysaccharide core region of gram-negative bacilli

Abstract

Summary.Monoclonal anti bodies to the lipopolysaccharide (LPS) core region were produced by immunising mice with Escherichia coli strain J5 (chemotype Rc). One of these bound to the deepest part of the core, i.e., Lipid A, and reacted with other heatkilled but not live gram-negative bacilli, including E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. Eight other monoclonal antibodies, binding to the terminal glucose residue of Rc LPS, reacted with live cells of E. coli strains only. Thus, the 0 antigen does not necessarily render the core inaccessible to antibody. However, despite binding to live bacteria, these monoclonal antibodies neither enhanced phagocytic killing, nor protected mice from dying from gram-negative infection or endotoxaemia. It is concluded that antibodies reacting with the most immunodominant parts of the J5 core are not protective.

Antigenic and immunogenic differences in lipopolysaccharides of Escherichia coli J5 vaccine strains of different origins

“…Rc-specific mAb 4 (IgG2a) has been described previously (Appelmelk et al, 1988); it was obtained using boiled strain J5(a) cells as a vaccine.…”

“…The nonpurified mAbs were stored in small portions at -80 "C and thawed only once. The purified mAbs were stored at 4 "C. The procedures used for vaccination, and for hybridoma selection and growth have been described previously (Appelmelk et al, 1988).…”

A comparison of specificity and biological activity of polyclonal and monoclonal antibodies raised against Salmonella minnesota R595 lipopolysaccharide

“…However, results have not always been consistent (Appelmelk et al, 1988). One problem in resolving these dilemmas has been the use of heterogeneous antibody preparations.…”

“…One problem in resolving these dilemmas has been the use of heterogeneous antibody preparations. Therefore, several investigators have produced anti-core MAbs from mouse cells (Bogard et al, 1984;Dunn et al, 1985a, b;1986;Appelmelk et al, 1988) and human cells (Raubitschek et al, 1985;Teng et al, 1985;Ramachandraet al, 1988). A second problem has been that neither the mechanism by which these antisera exert their protective effects nor the epitope(s) against which they are directed have been resolved (Wolff, 1982).…”

Use of Immunoglobulins in Prevention and Treatment of Infection in Critically III Patients: Review and Critique

“…In recent years, several MoAbs have been developed that recognize various epitopes of the core region of endotoxin [30,33,[42][43][44][45][46][47][48][49][50][51][52]. Two of these MoAbs, both of the IgM class, have been tested for treatment of patients with gram-negative infections.…”