Neuregulins and erbB receptor expression in adult human oligodendrocytes.
We have previously reported that neonatal rat oligodendrocytes (OLGs) express and secrete neuregulins (NRGs) (Raabe et al., 1997). This laboratory has also shown that NRGs stimulate the differentiation of neonatal rat OLGs and that these cells express the erbB receptors for NRGs (Raabe et al., 1997). In this study, we have characterized NRG expression in adult human OLG cultures isolated from the temporal lobe resection of intractable epilepsy patients. Using immunocytochemistry and Western blotting, we find that adult human OLGs contain both the alpha and beta isoforms of NRGs. In addition, Western blots show that the adult human OLGs secrete both isoforms as N-glycosylated molecules. These cells also express all four erbB receptor subtypes, and possibly an activated erbB receptor. The observation that these cells synthesize and secrete their own NRGs, and possibly express a tyrosine-phosphorylated erbB receptor, is consistent with autocrine and/or paracrine signaling. Amplification of this signaling may provide a useful mechanism to stimulate differentiation of adult human OLGs in demyelinating disease.
Deadwyler
G D
GD
Research Service, Hines VA Hospital, Hines, Illinois 60141, USA.
Pouly
S
S
Antel
J P
JP
Devries
G H
GH
D000328:Adult; D015153:Blotting, Western; D002478:Cells, Cultured; D066246:ErbB Receptors / Q000032:analysis / Q000096:biosynthesis*; D006801:Humans; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism; D020890:Neuregulin-1 / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism; D020880:Neuregulins / Q000032:analysis / Q000096:biosynthesis* / Q000378:metabolism; D009836:Oligodendroglia / Q000737:chemistry / Q000166:cytology / Q000378:metabolism*; D010766:Phosphorylation; D011498:Protein Precursors / Q000737:chemistry / Q000378:metabolism; D017434:Protein Structure, Tertiary; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis / Q000096:biosynthesis*; D014443:Tyrosine / Q000378:metabolism
D066246:ErbB Receptors; D009419:Nerve Tissue Proteins; D020890:Neuregulin-1; D020880:Neuregulins; D011498:Protein Precursors; D018719:Erb-b2 Receptor Tyrosine Kinases; D014443:Tyrosine; C094131:NRG1 protein, human; C490580:Nrg1 protein, rat