Is Pasteurella tularensis Lipopolysaccharide an Endotoxin
Abstract
Pasteurella tularensis cell wall or lipopolysaccharide (LPS), unlike Salmonella enteritidis LPS, is nontoxic for mice previously sensitized by enterotoxin B. Studies in normal mice challenged with P. tularensis 425, a strain of intermediate virulence, demonstrated that P. tularensis LPS, like S. enteritidis LPS, can increase host resistance with resultant reduction in disease severity and mortality. In contrast to S. enteritidis LPS, P. tularensis LPS administration to tularemia-immunized mice 24 hours after challenge with highly virulent P. tularensis SCHU S4 resulted in little or no reduction in resistance. The LPS of each species enhanced resistance of nonimmunized mice to SCHU S4 challenge with LPS was inoculated 24 or 72 hours before infection. However, in immunized mice, the enhancement of host resistance was significant only when mice were treated with S. enteritidis LPS before infection. Therefore, P. tularensis LPS as an endotoxin is unusual among the endotoxins of gram- negative bacteria, and further study of methods of extraction and structural identification may lead to a better understanding of the origins of the varied activities within this complex molecule and of LPS endotoxins in general.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1970
- Accession Number
- AD0864723
Entities
People
- Maurice L. Guss