Protection against gram-negative bacteremia and endotoxemia with human monoclonal IgM antibodies.

Abstract

Hybridomas producing human monoclonal IgM antibodies (mAbs) against bacterial lipopolysaccharide (LPS) were generated by fusion of B lymphocytes from sensitized human spleen with heteromyeloma cells. The splenocytes were from patients undergoing splenectomy during staging for Hodgkin disease after vaccination with the J5 mutant of Escherichia coli, which is deficient in 0 antigenic side chains. This deficiency exposes the core oligosaccharide, common to LPS of all Gram-negative bacteria. The mAbs cross-reacted strongly with endotoxins from a wide range of unrelated species of Gram-negative bacteria. The mAbs also gave strong protection against LPS in the dermal Shwartzman reaction and against lethal Gram-negative bacteremia in mice. Two separate sites were selected for simultaneous subcutaneous injection of 1 ml of J5 vaccine, and similar injections were repeated 48 hr later. Each milliliter of the vaccine contained 5 x 109 heat-inactivated cells of the J5 mutant of E. coli 0111. The method for preparing the vaccine is described elsewhere (4). Our previous experience with over 600 volunteers showed that vaccinations given in this fashion produced minimal side effects (4), and none were reported by the recipients in this study. They underwent staging laparotomies and splenectomies 1 week after immunization. At Feb. 4, 1984. $Deceased, Dec. 5, 1984Dec. 5, . 1790 The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

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

“…Indeed, using purified MoAb instead of crude hybridomal fluid, we could not demonstrate that HA-IA could be protective [26] in models very similar to those used by Teng et al [30]. In addition, in contrast to type-specific LPS antibodies, HA-IA did not suppress LPS-induced secretion of tumor necrosis factor in mice, a circumstance suggesting that HA-IA was not able to prevent LPS from reaching its target on macrophages [26].…”

“…Moreover, the animal models studied, the mode of challenge, and the nature of LPS or of bacteria used for challenge are parameters that all could have an impact on the protective efficacy of these preparations [29]. However, these considerations cannot explain all the discrepancies in data; varying results were sometimes obtained despite the use of similar antibodies, similar animal models, and similar bacterial or LPS challenges [8,9,26,27,30]. Therefore, it can bepostulated that additional, unknown negative or positive factors sometimes operate.…”

“…Indeed, ascitic and hybridomal fluids can contain various proteins and peptides, such as cytokines, some of which might be able to bind to LPS or to induce some tolerance to LPS in experimental animals. Most experimental studies of protection that have been reported, including those by Teng et al [30] and Young et al [33], have involved ascitic or hybridomal fluids. Experimental variability might account for important differences in survival rates noted from one experiment to another, so the reporting of only part of the experiments might introduce some element of bias [34,35].…”

“…The second MoAb, subsequently designated as HA-lA, was produced by Teng and co-workers [30] from a hybridoma obtained by fusing B lymphocytes from human spleen with heteromyeloma cells. The researchers used splenocytes taken from one patient with Hodgkin's disease who was undergoing splenectomy and who had previously been vaccinated with the J5 mutant of E. coli.…”

“…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.…”