The interplay between surfaces and soluble factors define the immunologic and angiogenic properties of myeloid dendritic cells

Herewith we studied the effect of different surfaces and soluble factors on the biology of DCs. To accomplish this, we cultured murine myeloid(m) DCs on surfaces coated with fibronectin, collagen I, gelatin, and Matrigel using poly-D-lysine and polystyrene as non-biological surfaces. Further, we cultured these cells in the presence of regular DC medium (RPMI 10% FBS) or commercially available endothelial medium (EGM-2). We determined that mDCs could be kept in culture up to 3 weeks in these conditions, but only in the presence of GM-CSF. We were able to determine that long-term DC cultures produce an array of angiogenic factors, and that some of these cultures still retain the capability to induce T cell responses.Altogether these data indicate that in order to design DC-based vaccines or treatments focused on changing the phenotype of DCs associated with diseases such as cancer or atherosclerosis, it becomes necessary to fully investigate the microenvironment in which these cells are present or will be delivered.Dendritic cells (DCs) are professional antigen presenting cells (APCs) found in peripheral tissues and in immunological organs such as thymus, bone marrow, spleen, lymph nodes and Peyer's patches [1-3]. In the mouse, DCs can be broadly divided into plasmacytoid and myeloid DCs [4]. Plasmacytoid DCs (pDCs) are characterized by the expression of B220 but no CD11b and produce large amounts of type-1 interferon in response to viral infections [5,6]. On the other hand, bone marrow-derived DCs (myeloid DCs) are present in most tissues and are characterized by coexpression of CD11c and CD11b markers. As reviewed by Breckpot et al. (2009), these DCs respond to GM-CSF and are capable of producing IL-12 in response to toll-like receptor ligands. Interestingly, DCs have been shown to possess a remarkable cellular plasticity. For example, pDCs could acquire myeloid DC characteristics under the influence of viral infection [5].In order to elicit productive T cells respo