Features of skin-coincubated macrophages that promote recovery from spinal cord injury.

Uncontrolled inflammation is considered to exacerbate the neuronal loss that follows spinal cord trauma. However, controlled inflammation response appears to be beneficial. Skin-coincubated macrophages injected into contused spinal cord of rats resulted in improved motor recovery and reduced spinal cyst formation. The macrophages express elevated levels of cell-surface molecules CD80, CD86, CD54 and MHC-II, markers characteristic of antigen presenting cells (APCs). Additionally, skin-coincubation elevates secretion of interleukin-1 beta (IL-1 beta) and Brain-Derived Neurotrophic Factor (BDNF), and reduces secretion of tumor necrosis factor alpha (TNF-alpha). We propose that macrophages activated by skin-coincubation bolster neuroprotective immune activity in the spinal cord, making the environment less cytotoxic and less hostile to axonal regeneration.