Given our data demonstrating common expression of genes with this pathway (Ccl5, Ccr5, Cfl1) that overlap with those induced by IL-4, mechanistic studies aimed at understanding the role of Ccl5/Ccr5 signaling within macrophages, the specific functions of this macrophage subset, and the downstream effects on disc degeneration are warranted. This evidence concerns the gene CCR5 and intervertebral disk degenerative disorder.