CD200 and spina bifida: Knowing the exhisting neural tissue damage in utero in spina bifida and given the importance of this immune ligand-receptor system in regulating microglial expression during brain development and microglial priming; we hypothezised that spina bifida suffer a progressive astrroglial and microglial activation during gestation and the microglia priming may be related to the alteration of the CD200-CD200R system.