Dendritic cells (DCs) can be generated from peripheral blood mononuclear cells (PBMC) after stimulation with exogenous granulocyte-macrophage colony stimulating factor and interleukin (IL)-4. Further, extravasation of monocytes through human endothelial cells can also cause differentiation, maturation, and expression of DC-specific phenotype. However, it is unclear whether human DCs can be generated from monocytes under the influence of xenogeneic endothelial cells in the absence of exogenous cytokines. We therefore analyzed and compared the effect of human and porcine endothelial cells on the differentiation of human monocytes into DC.