Inhibition of central axon regeneration: perspective from chondroitin sulfate proteoglycans in lamprey spinal cord injury.

Background: Failure of axon regeneration after spinal cord injury （SCI） underlies the paralysis that so profoundly affects patients’ quality of life.Many factors are involved in the regeneration failure.Chondroitin sulfate proteoglycans （CSPGs）,normal constituents of the perineuronal nets in central nervous system （CNS）,are secreted at the injury site and initially were thought to act as a purely physical barrier.In the past decade,the receptor-like protein tyrosine phosphatases,protein tyrosine phosphatase sigma （PTPσ）,and leukocyte common antigen-related phosphatase （LAR）,