However, addition of the human recombinant IL-1β protein to the system resulted in increased expression of caspase-1 in HNPC, suggesting that the inflammatory response experienced by HNPC in IDD could originate in a different cell type like annulus fibrosus cells or even dorsal root ganglia or infiltrated inflammatory cells such as neutrophils. The gene discussed is CASP1; the disease is intervertebral disk degenerative disorder.