Enzymatically deacylated Neisseria lipopolysaccharide (LPS) inhibits murine splenocyte mitogenesis induced by LPS.
AUTOR(ES)
Erwin, A L
RESUMO
Acyloxyacyl hydrolase is a leukocyte enzyme that selectively removes the secondary acyl chains from the lipid A moiety of gram-negative bacterial lipopolysaccharides (LPS). As predicted by the reported contribution of secondary acyl chains to the bioactivities of lipid A analogs, enzymatic deacylation of Salmonella typhimurium Rc LPS substantially reduces its potency in the dermal Shwartzman reaction and in several in vitro assays that measure responses of human endothelial cells and neutrophils, whereas the potency of this LPS for inducing murine splenocyte mitogenesis is affected much less. In the experiments described here, we studied the impact of acyloxyacyl hydrolysis on the bioactivities of several LPS that differ from Salmonella LPS in carbohydrate and lipid A structures. Deacylated LPS from Escherichia coli, Haemophilus influenzae, Neisseria meningitidis, and S. typhimurium were similarly reduced in potency in the Limulus lysate test (30- to 60-fold reduction in potency relative to the corresponding mock-treated LPS), and the ability of all of these deacylated LPS to stimulate neutrophil adherence to human endothelial cells was reduced by a factor of 100 or more. For LPS from E. coli, H. influenzae, and Pseudomonas aeruginosa, the impact of deacylation on spleen cell mitogenesis was also similar to that observed for S. typhimurium LPS: deacylation reduced potency by less than 15-fold. Unexpectedly, the potency of Neisseria LPS in the murine splenocyte mitogenicity test was reduced over 100-fold by deacylation, and deacylated Neisseria LPS could block the mitogenic activity of Neisseria and Salmonella LPS. These studies indicate that the contribution of secondary acyl chains to the bioactivities of a given LPS cannot be predicted with confidence from the reported structure-activity relationships of lipid A or from the behavior of other deacylated LPS.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=257937Documentos Relacionados
- Diphosphoryl lipid A derived from lipopolysaccharide (LPS) of Rhodopseudomonas sphaeroides inhibits activation of 70Z/3 cells by LPS.
- Cytokine induction by lipopolysaccharide (LPS) corresponds to lethal toxicity and is inhibited by nontoxic Rhodobacter capsulatus LPS.
- Prolonged expression of lipopolysaccharide (LPS)-induced inflammatory genes in whole blood requires continual exposure to LPS.
- Antibiotic-Induced Lipopolysaccharide (LPS) Release from Salmonella typhi: Delay between Killing by Ceftazidime and Imipenem and Release of LPS
- Protection of mice against the lethal toxicity of a lipopolysaccharide (LPS) by immunization with anti-idiotype antibody to a monoclonal antibody to lipid A from Eikenella corrodens LPS.