(2005)[15] observed that non-myelinated or myelinated Schwann cells in contact with an injured axon enter cell cycle thus leading to proliferation. Observed time duration for Schwann cell divisions were approximately 3 days after injury.[16] Possible sources of proliferation signal are attributed to the ErbB2 receptors and the ErbB3 receptors. This proliferation could further enhance the myelin cleaning rates and plays an essential role in regeneration of axons observed in PNS.