Involvement of insulin-like growth factor binding protein-2 in activated microglia as assessed in post mortem human brain.
In vitro studies suggest that insulin-like growth factor (IGF)-I is a mitogen for microglia/macrophages. The actions of IGF-I are mediated by IGF-I receptors and modulated by IGF binding proteins (IGFBPs). The aim of this study was to investigate IGF-I receptors and IGFBPs in human microglia in normal brain white matter and active lesions of multiple sclerosis, which contain activated microglia/macrophages. Methods used were immunohistochemistry and confocal laser microscopy. IGF-I receptors were demonstrated in both resting and activated microglia. In resting conditions, microglia displayed no immunoreactivity for any of the six IGFBPs, whereas activated microglia/macrophages were immunoreactive for IGFBP-2 only. Our data suggest an important function for IGFBP-2 in IGF-I actions in activated microglia/macrophages in human brain.
Chesik
Daniel
D
Department of Neurology, University Hospital Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands.
De Keyser
Jacques
J
Wilczak
Nadine
N
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D005260:Female; D006801:Humans; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000032:analysis / Q000502:physiology*; D008297:Male; D017628:Microglia / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D017451:Receptors, Somatomedin / Q000032:analysis / Q000096:biosynthesis
D018971:Insulin-Like Growth Factor Binding Protein 2; D017451:Receptors, Somatomedin