TI - MMP-28 as a regulator of myelination . AB - Background Matrix metalloproteinase-28 ( MMP-28 ) is a poorly understood member of the matrix metalloproteinase family . Metalloproteinases are important mediators in the development of the nervous system and can contribute to the maturation of the neural micro-environment . Results MMP-28 added to myelinating rat dorsal root ganglion ( DRG ) co cultures reduces myelination and two antibodies targeted to MMP-28 ( pAb180 and pAb183 ) are capable of binding MMP-28 and inhibiting its activity in a dose -dependent manner . Addition of 30 nM pAb180 or pAb183 to rat DRG cultures resulted in the 2.6 and 4.8 fold enhancement of myelination respectively while addition of MMP-28 to DRG co cultures resulted in enhanced MAPK , ErbB2 and ErbB3 PHOSphorylation . MMP-28 protein expression was increased within demyelinated lesions of mouse experimental autoimmune encephalitis ( EAE ) and human multiple sclerosis lesions compared to surrounding normal tissue . Conclusion MMP-28 is upregulated in conditions of demyelination in vivo , induces signaling in vitro consistent with myelination inhibition and , neutralization of MMP-28 activity can enhance myelination in vitro . These results suggest inhibition of MMP-28 may be beneficial under conditions of dysmyelination .