CD4 and intervertebral disk degenerative disorder: Although the etiology of IDD is considered to be multifactorial, ranging from genetic predisposition and ageing to lifestyle, this condition is characterized by extracellular matrix degradation and excessive cell apoptosis, attributed to inflammation with the recruitment of immune cells such as CD4+, CD8+ T-cells, T-regs, neutrophils, macrophages, and mast cells and inflammatory cytokines including IL-1β and TNF-α.