Spontaneous production of monocyte chemoattractant protein-1 and interleukin-8 by the human lumbar intervertebral disc

Abstract

Study design: Scoliotic and herniated human intervertebral disc tissue obtained intraoperatively was cultured, and the medium was analyzed for the production of monocyte chemoattractant protein-1 and interleukin-8.

Objectives: This study was conducted to determine whether the human intervertebral disc is capable of spontaneous production of the chemokines monocyte chemoattractant protein-1 and interleukin-8.

Summary of background data: Lumbar disc herniations undergo spontaneous regression with time. This is believed to occur via macrophage-mediated phagocytosis of herniated disc material. Monocyte chemoattractant protein-1, a chemotactic agent for macrophages, has recently been identified in rat intervertebral disc tissue.

Methods: Disc material obtained from patients undergoing surgery for scoliosis and sciatica was cultured using a serumless technique, and the medium was subsequently analyzed for levels of monocyte chemoattractant protein-1 and interleukin-8.

Results: Monocyte chemoattractant protein-1 and IL-8 were detected in both control and herniated disc specimens. Noncontained herniations produced higher levels of chemokines than those with an intact anulus.

Conclusions: Human intervertebral disc tissue is capable of spontaneously producing the proinflammatory chemokines monocyte chemoattractant protein-1 and interleukin-8. These are chemotactic for macrophages and capillaries and may explain the ingrowth of granulation tissue seen in spontaneous disc herniation resorption.