The invention provides isolated dendritic cells genetically modified to express
a selectin polypeptide, optionally treated with activated platelets or membrane
microparticles thereof. The invention also provides isolated platelet modified
dendritic cells. Methods for delivering the modified dendritic cells to peripheral
lymph nodes and methods for using the modified dendritic cells to stimulate immune
responses also are provided. Vaccine compositions containing the modified dendritic
cells also are provided.