Abstract: A transplant/implant device for delivering at least one predetermined biologically active compound to a human or animal host system or for another biological function in the host system is produced by genetically engineering vital chondrocytes or mixing chondrocytes with another type of native or genetically engineered cells or mixing chondrocytes with artificial particles having a size comparable to the size of cells or combining at least two of the named steps of engineering or mixing and by subjecting the chondrocytes or the mixture comprising the chondrocytes to three dimensional culture conditions for in vitro production of cartilaginous tissue whereby the cells and/or the artificial particles are immobilized in the cartilaginous tissue. The chondrocytes produce and maintain the cartilaginous tissue and the chondrocytes themselves or cells of another cell type immobilized in the cartilaginous tissue are able to produce and secrete the at least one predetermined compound.