Despite the clinical relevance of back pain and intervertebral disc herniation, the lack of reliable models has strained their molecular understanding. We characterized the lumbar spinal phenotype of C57BL/6 and SM/J mice during aging. Interestingly, old SM/J lumbar discs evidenced accelerated degeneration, associated with high rates of disc herniation. SM/J AF's and degenerative human's AF transcriptomic profiles showed altered immune cell, inflammation, and p53 pathways. Old SM/J mice presented increased neuronal markers in herniated discs, thicker subchondral bone, and higher sensitization to pain. Dorsal root ganglia transcriptomic studies and spinal cord analysis exhibited increased pain and neuroinflammatory markers associated with altered extracellular matrix regulation. Immune system single-cell and tissue level analysis showed distinctive T-cell and B-cell modulation and negative correlation between mechanical allodynia and INF-α, IL-1β, IL2, and IL4, respectively. This study underscores the multisystemic network behind back pain and highlights the role of genetic background and the immune system in disc herniation disease.
