Antigen‐presenting cell function of dendritic cells and macrophages in proliferative T cell responses to soluble and particulate antigens

Abstract
The capacity of dendritic cells (DC) and macrophages (MΦ) to present soluble and particulate antigen was tested in an ovalbumin (OVA)-specific T cell proliferation assay. In a comparative investigation we found that both DC and MΦ, were able to present soluble OVA, but that only MΦ, could present insolubilized OVA to T cells. DC were found to be able to present OVA in collaboration with MΦ. The failure of DC to present insolubilized OVA is probably caused by their inability to endocytose these antigens. DC appeared not to endocytose substantial amounts of soluble OVA either. In contrast to MΦ, antigen presentation by DC is not blocked by lysosomotropic drugs. Taken together, these observations suggest that DC can present soluble protein antigens without intracellular degradation.