Interactions of proteoliposomes from serogroup BNeisseria meningitidiswith bone marrow-derived dendritic cells and macrophages: adjuvant effects and antigen delivery

Exposure to proteoliposomes from serogroup BNeisseria meningitidis(PL) induced up-regulation of MHC-II, MHC-I, CD40, CD80 and CD86 expression on the surface of murine bone marrow-derived dendritic cells (DC). CD40, CD80 and CD86 were up-regulated on bone marrow-derived macrophages (M[phi]) upon stimulation with PL. Both DC and M[phi] released TNFα, but only DC produced IL12(p70) in response to PL. A small increase in the expression of MHC-II, CD40 and CD86, as well as production of IL12(p70), was observed on the cell surface of DC, but not M[phi] from LPS-non-responder C3H/HeJ after exposure to PL. DC, but not M[phi], incubated with PL containing ovalbumin (PL-OVA) presented OVA-specific peptides to CD4+and CD8+OVA-specific T-cell hybridomas. These data clearly indicate that PL exert an immunomodulatory effect on DC and M[phi], with some contribution of non-LPS components besides the main role of LPS. The work also shows the potential of PL as a general system to deliver antigens to DC for presentation to CD4+and CD8+T-cells.