The mononuclear phagocyte cell system includes monocytes, macrophages anddendritic cells which are important cells in order to recognize, ingest, destroyand also present part of a pathogen to T-lymphocytes in order to activate theadaptive immune system. Dendritic cells (DCs) stand out in their ability tostimulate T-lymphocytes and are also believed to be important to keeptolerance for “self-antigens”.Therefore DCs are of interest for use in immunotherapy studies. However inmost such studies to date, DC-like cells have been used, so called monocytederived dendritic cells (moDCs).The aim of this thesis was to investigate the early events following in vitroactivation of highly purified human DCs. In the first study we observed thatthe production of IL-8 and down regulation of CD128b preceded surfaceexpression of MHC class II and CD40, 80 and 86. We have in the followingstudies used and demonstrated the practical use of zeolite particles as ligandcarriers with the purpose to study the uptake mechanisms deployed byphagocytes. We show the advantage of using zeolite particles, due to theirability to bind various types of ligands i.e. proteins, oligonucleotides,lipophilic, and hydrophobic molecules. In addition, we have adsorbed biomolecules in sequential steps, which demonstrates the potential of coadsorbing ligands e.g. for targeting a specific endosomal compartmenttogether with molecules sensing the endosomal microenvironment.Coating zeolite particles with different biomolecules might provide furtherunderstanding of mechanisms involved in antigen sorting into endocyticcompartments.