A method of assaying wound healing can include: growing cells on the matrix in the first flow channel; introducing an agent that removes the matrix from the junction; introducing a matrix material into the second flow channel so as to form the second matrix in the second flow channel and junction; and detecting cellular migration into the junction onto the second matrix. The agent that removes the matrix can include a biomolecule or chemical agent. The method can include removing cells in the matrix in the junction before introducing the matrix material into the second flow channel. A bioactive agent can be introduced into the junction to determine if it modulates cellular migration and/or clot formation into the intersection openings of tissue and vascular channels.