Abstract: Provided are compositions and methods of making a hydrogel-forming composition comprising decellularized porcine nucleus pulposus tissue that is solubilized and supplemented with collagen, then neutralized and thermally gelled in the presence of genipin. The hydrogel-forming composition may be injected into a joint or surrounding tissue of a subject having pain or inflammation. The pain or inflammation may be caused by degeneration of the intervertebral disc (IVD), wherein administration of the hydrogel-forming composition into the IVD may restore the lost disc volume and alleviate the pain and inflammation.