When GM-CSF was used to treat CIDP-patient sera-exposed Schwann cells, the cytokine rescued the levels of p57kip2, c-Jun, BDNF, and GDNF mRNA expression and led to an increase in NGF mRNA above both CIDP patient sera-treated and control-treated Schwann cells. Here, JUN is linked to chronic inflammatory demyelinating polyradiculoneuropathy.