Localization of gp130 in the developing and adult mouse cerebellum

Interleukin-6 (IL-6) type cytokines show functional redundancy in the immun e, hematopoietic, and nervous system, which is believed to result from shar ing of the signal transducing receptor gp130. IL-6 type cytokines and their binding receptors have been localized in the adult cerebellum. However, th e cellular localization and developmental regulation of gp130 in the cerebe llum have not been determined. In the present study the expression pattern of gp130 in the developing and adult mouse cerebellum was investigated. At embryonic day (E)15 and E17, gp130 immunoreactivity is present primarily in fiber bundles that course from the brainstem to the cerebellum. At postnat al day (P)0, gp130 immunoreactivity first appears in the Purkinje cell laye r, external granule cell layer, and cerebellar nuclei. As Purkinje cells di fferentiate, gp130 immunoreactivity progressively extends from the cell bod y along their developing dendritic arbor. All Purkinje cells show intense g p130 immunoreactivity in their cell bodies by P7. In contrast the gp130 imm unoreactivity detected in fiber bundles at E15 and E17 is downregulated pos tnatally, and cannot be detected after P7. Granule cells show gp130 immunor eactivity at PO in the external granule cell layer and subsequently in the internal granule cell layer. Astrocytes in the white matter express gp130 a t PO, and show intense gp130 immunoreactivity between P7 and P14. As the ce rebellum matures gp130 immunoreactivity in the white matter decreases. The present description of the differential spatial and temporal distribution o f gp130 provides an initial step in defining specific cellular populations that are potential targets of IL-6 type cytokines during cerebellar ontogen y. (C) 2000 Elsevier Science B.V. All rights reserved.