Induction of death receptor CD95 and co-stimulatory molecules CD80 and CD86 by meningococcal capsular polysaccharide-loaded vaccine nanoparticles

AAPS J. 2014 Sep;16(5):986-93. doi: 10.1208/s12248-014-9635-2. Epub 2014 Jul 1.

Abstract

Neisseria meningitidis is a leading cause of bacterial meningitis and sepsis, and its capsular polysaccharides (CPS) are a major virulence factor in meningococcal infections and form the basis for serogroup designation and protective vaccines. We formulated a novel nanovaccine containing meningococcal CPS as an antigen encapsulated in albumin-based nanoparticles (NPs) that does not require chemical conjugation to a protein carrier. These nanoparticles are taken up by antigen-presenting cells and act as antigen depot by slowly releasing the antigen. In this study, we determined the ability of CPS-loaded vaccine nanoparticles to induce co-stimulatory molecules, namely CD80, CD86, and CD95 that impact effective antigen presentation. Co-stimulatory molecule gene induction and surface expression on macrophages and dendritic cells pulsed with meningococcal CPS-loaded nanoparticles were investigated using gene array and flow cytometry methods. Meningococcal CPS-loaded NP significantly induced the surface protein expression of CD80 and CD86, markers of dendritic cell maturation, in human THP-1 macrophages and in murine dendritic cells DC2.4 in a dose-dependent manner. The massive upregulation was also observed at the gene expression. However, high dose of CPS-loaded NP, but not empty NP, induced the expression of death receptor CD95 (Fas) leading to reduced TNF-α release and reduction in cell viability. The data suggest that high expression of CD95 may lead to death of antigen-presenting cells and consequently suboptimal immune responses to vaccine. The CPS-loaded NP induces the expression of co-stimulatory molecules and acts as antigen depot and can spare antigen dose, highly desirable criteria for vaccine formulations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • B7-1 Antigen / genetics
  • B7-1 Antigen / metabolism*
  • B7-2 Antigen / genetics
  • B7-2 Antigen / metabolism*
  • Cell Line
  • Cell Survival / drug effects
  • Chemistry, Pharmaceutical
  • Dendritic Cells / drug effects*
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism
  • Dose-Response Relationship, Drug
  • Humans
  • Macrophages / drug effects
  • Macrophages / immunology
  • Macrophages / metabolism
  • Meningococcal Vaccines / chemistry
  • Meningococcal Vaccines / immunology
  • Meningococcal Vaccines / pharmacology*
  • Mice
  • Nanoparticles*
  • Nanotechnology
  • Neisseria meningitidis / immunology*
  • Nitric Oxide / metabolism
  • Polysaccharides, Bacterial / chemistry
  • Polysaccharides, Bacterial / immunology
  • Polysaccharides, Bacterial / pharmacology*
  • RNA, Messenger / metabolism
  • Serum Albumin, Bovine / chemistry
  • Technology, Pharmaceutical / methods
  • Tumor Necrosis Factor-alpha / metabolism
  • Up-Regulation
  • fas Receptor / genetics
  • fas Receptor / metabolism*

Substances

  • B7-1 Antigen
  • B7-2 Antigen
  • CD86 protein, human
  • Cd86 protein, mouse
  • FAS protein, human
  • Fas protein, mouse
  • Meningococcal Vaccines
  • Polysaccharides, Bacterial
  • RNA, Messenger
  • Tumor Necrosis Factor-alpha
  • fas Receptor
  • Serum Albumin, Bovine
  • Nitric Oxide