Immunochemical Investigations of Cell Surface Antigens of Anaerobic Bacteria.
Abstract
Bacterial lipopolysacchrides were extracted from Bacteroides fragilis subspecies fragilis. These lipopolysaccharides were found to lack 2-keto-3-desoxyoctonate and heptose, sugars which make up part of the inner core of most bacterial endotoxins. Over 98% of the lipid portion of this material could easily be removed with chloroform-methanol and alcohol, a finding which indicates a loose association between the polysaccharide and lipid moieties. The lipopolysaccharides caused gelation of the Limulus lysate at a concentration significantly higher than that for the endotoxin of Salmonella typhi. None of these extracts were found to be lethal in 10-day of chick embryos at doses of 200 ug per egg, wherease the endotoxin of Neisseria meningitidis was lethal at 1.2 ug per egg. The local Scwartzman reaction could not be induced at levels of up to 1,000 ug per rabbit, whereas a (control) endotoxin of Salmonella typhi induced this phenomenon at 3 ug per rabbit. Intact oxygen-killed B. fragilis failed to provoke the local Scwartzman reaction at doses of 2,500 ug. These results indicate that B. fragilis has a lipopolysaccharide different from that of most gram-negative bacteria. Although it retains some of the chemical and biologic properties of classical endotoxin, it seems to lack others. This observation may have significant clinical implications. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1976
- Accession Number
- ADA103150
Entities
People
- Dennis L Kasper
Organizations
- Harvard Medical School