We produced nine monoclonal antibodies (MAbs) directed against the West Nile virus E glycoprotein using three different immunization strategies: inactivated virus, naked DNA, and recombinant protein. Most of the MAbs bound to conformation dependent epitopes in domain III of the E protein. Four of the MAbs neutralized WNV infection and bound to the same region of domain III with high affinity. The neutralizing MAbs were obtained from mice immunized with inactivated virus alone or in combination with a DNA plasmid. In contrast, MAbs obtained by immunization with a soluble version of the E glycoprotein did not exhibit neutralizing activity. These non-neutralizing antibodies were cross-reactive with several other flaviviruses, including Saint Louis encephalitis, Japanese encephalitis, Yellow Fever and Powassan viruses. Interestingly, some non-neutralizing MAbs bound with high affinity to domains I or III, indicating that both affinity and the precise epitope recognized by an antibody are important determinants of WNV neutralization.

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All Enterobacteriaceae express a polysaccharide known as Enterobacterial Common Antigen (ECA), which is an attractive target for the development of universal acting immunotherapies. We describe here the first chemical synthesis of ECA derived oligosaccharides for the development of such therapies. A number of synthetic challenges had to be addressed including the development of concise synthetic procedures for unusual monosaccharides, the selection of appropriate orthogonal protecting groups, the development of stereoselective glycosylation protocols, appropriate timing for the introduction of carboxylic acids of ManpNAcA moieties and conditions for the reduction of multiple azido moieties. The synthetic compounds were employed to uncover immuno-dominant moieties of ECA. Furthermore, a mAb was developed that binds to ECA and can selectively recognize a wide range of intact Enterobacteriaceae.

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A relatively nonpolar unidentified phospholipid (phospholipid X), isolated from the gram-negative marine bacterium MB 45, was characterized both chromatographically and by chemical analysis. Phospholipid X was shown to be an acidic phospholipid without vicinal hydroxyl, free-amino, or amide groups. The presence of O-alkenyl groups was indicated by a positive reaction for plasmalogen. Mild alkaline methanolysis of phospholipid X yielded only glycerophosphorylglycerol as the derivative. Acetolysis produced only diacylglycerol monoacetate. Cleavage of O-alkenyl chains by methanolic hydrochloride resulted in the formation of three lyso derivatives. It was estimated that 18.2% of phospholipid X was plasmalogen. From these data, together with chromatographic comparisons with standards, infrared spectra, a molecular weight estimation, and the determination of the glycerol-phosphate-acyl ester ratio, it was concluded that phospholipid X was bisphosphatidic acid mixed with its plasmalogen analogues.