Liposomal meningococcal B vaccine enhances dendritic cell activation.

2003 NOV 5 - (NewsRx.com & NewsRx.net) -- A liposomal meningococcal B vaccine enhanced the activation of dendritic cells.

"The effect of targeting strategies for improving the interaction of liposomal PorA with dendritic cells (DCs) on the immunogenicity of PorA was investigated. PorA, a major antigen of Neisseria meningitidis, was purified and reconstituted in different types of (targeted) liposomes, i.e, by using mannose or phosphatidylserine as targeting moieties, or with positively charged liposomes," investigators in Netherlands report.

"We studied the efficiency of liposome uptake and its effect on the maturation of and interleukin 12 (IL-12) production by murine DCs," stated Carmen Arigita and collaborators at Utrecht University and the Netherlands Vaccine Institute. "Moreover, mice were immunized subcutaneously to study the localization and immunogenicity of PorA liposomes. Uptake of liposomes by DC was significantly increased for targeted liposomes and resulted in the maturation of DC, but to various degrees."

"Maturation markers (i.e., CD80, CD86, major histocompatibility complex class II, and CD40) showed enhanced expression on DC incubated with targeted PorA liposomes relative to those incubated with nontargeted PorA liposomes," reported the researchers. "Moreover, only the uptake of targeted PorA liposomes induced production of IL-12 by DC, with levels similar to those produced by lipopolysaccharide (LPS)-pulsed DCs. Mannose-targeted PorA liposomes administered subcutaneously had an increased localization in draining lymph nodes compared to nontargeted PorA liposomes. Liposomes in ...