Lipopolysaccharides VOLUME

Kav is the availability constant of a substance with molecular weight M, Ve is the elution volume, Vt is the total volume of the column, V0 is the void volume or the interstitial space between the beads in the bed. The void volume could not be determined by the elution volume of Blue Dextran 2000 (Pharmacia Fine Chemicals AB, Uppsala, Sweden, Mw about two million) since it would have separated in the column. We used a 0.5% lipopolysaccharide solution (Bacto Lipopolysaccharide W, Salmonella typhosa 0901 ref. nr. 3124-25, Difco Laboratories, Detroit, MI, USA) with a molecular weight of above 150,000,000, which is excluded by the gel. 

Inoculate commodity samples with a known amount of endotoxin (e.g., 10-100 ng Escherichia coli lipopolysaccharide, obtainable from several commercial sources). The endotoxin should be contained in a volume of water equal to the residual water volume following the washing procedure used prior to sterilization. 

Plate 8. Crystal structure of the outer membrane phospholipase A dimer from E. coU shown in the plane of the membrane. The top half of the molecule is located in the lipopolysaccharide monolayer facing the exterior of the cell. The phospholipid monolayer of the outer cell membrane would be located around the bottom half of the protein. Two calcium ions are shown at the active sites while Ser-144 of each active site is covalently modified with a hexadecylsulfonyl moiety represented in a ball and stick format. Structure is adapted from Ref. [12]. (See page 312 in this volume.)... 

A recently published fast-DC protocol, stimulating monocytes for only 2 days ex vivo in the presence of IFN-y and lipopolysaccharide (LPS), reported tumour-peptide-specific responses (to Her/2b) and decreased tumour volumes in vaccinated breast cancer patients [47], the mechanism being dependent on a delayed IL-12 burst. Alternatively, maturation can be induced in vivo following administration of the antigen-loaded DC with systemically applied antibodies cross-linking stimulatory molecules on DC, such as anti-CD40 antibody [48]. 

C.R.H. Raetz, Bacterial lipopolysaccharides a remarkable family of bioactive macro-amphiphiles, in Escherichia coli and Salmonella, Cellular and Molecular Biology, 2nd Edition, Volume I, Edited by F.C. Neidhardt, 19%, American Society for Microbiology, Washington,... 

---