S-type LPS represents the wild-type (wt) form of bacterial LPS. Highly water soluble including buffers containing divalent ions. Potent immunostimulatory agent. High dependancy for soluble or membrane-bound CD14 or soluble LPS binding protein (LBP). LPS of choice for experimental in vivo applications.

R-type LPS represents the mutant form of bacterial LPS. Variable solubility in certain buffers containing divalent ions. Extremely potent immunostimulatory agent. Low dependancy for soluble or membrane-bound CD14 or soluble LPS binding protein (LBP). LPS of choice for experimental in vitro (cellular assays) applications.