In vivo macrophage recruitment by murine intervertebral disc cells

An in vivo murine experiment was conducted to measure the capacities of via ble intervertebral disc cells to recruit inflammatory cells. The objective was to determine whether compounds secreted from viable cells induce inflam mation or whether inflammation in disc herniation simply requires exposure to structural cell or matrix components. Three tissue preparations were ins erted into the right lower peritoneal cavity of male mice: tissue with viab le annulus fibrosus and nucleus pulposus cells, tissue with viable annulus fibrosus cells. or devitalized annulus fibrosus and nucleus pulposus tissue . Controls included sham-operated and nonoperated groups. Mice were killed 1, 2, or 7 days after surgery. Macrophage recruitment occurred after exposu re to viable disc tissue but not after exposure to devitalized disc compone nts: recruitment increased over time, Viable disc cells play a role in the etiology of inflammation in disc herniation.