Patent ID: 7927599

Claim:
A therapeutic system comprising: (a) a housing configured to allow passage of a therapeutic agent, the housing having an interior and an exterior, the interior of the housing comprising: (i) a cell chamber, (ii) an auxiliary fluid chamber configured to house an auxiliary fluid, and (iii) an expandable chamber; the auxiliary fluid chamber being position between the cell chamber and the expandable chamber; and (b) a genetically altered chondrocyte retained within the cell chamber, the genetically altered chondrocyte modified to express a therapeutic agent; wherein the cell chamber includes a mechanism configured to allow selective release of the therapeutic agent; wherein the auxiliary fluid chamber is configured to deliver auxiliary fluid to the cell chamber; and wherein the expandable chamber includes an osmotic membrane configured to allow for the input of fluid to the expandable chamber such that auxiliary fluid is controllably introduced to the cell chamber in response to the expansion of the expandable chamber.