Figure 3.

Injectable cell carriers have been used for delivery to the nucleus pulposus (NP). This carrier is mixed with cells and cross-linked in a biocompatible process for in situ cross-linking in the NP space. Cell tracking can be accomplished via luciferase, as well as by other means. Delivery by needle puncture to the anulus fibrosus and NP remains the only established method to delivery large volumes of the cells, but may be destructive to the long-term viability of the intervertebral disc. Abbreviations: LM: laminin; NHS: N-hydroxysuccinimide; PEG: polyethylene glycol.