10-07-08(0:53:18)
Authors:
Knerlich-Lukoschus F, v. d. Ropp-Brenner B, Mehdorn HM, Held-Feindt J
Institutions:
Klinik für Neurochirurgie, UK S-H, Campus Kiel, Schittenhelmstrasse 10, D-24105 Kiel
Title of abstract : Chemokine Expression in the White Matter Spinal Cord Precursor Niche after Spinal Cord Contusion Injury in Adult Rats.
Abstract text:
Identification of mediators determining progenitor niches is a pre-requisite to stem cell therapy after spinal cord injury (SCI). To further identify chemokines/-receptors as potential modulators of progenitor cells, a subset of these molecules were investigated in parallel with Nestin, 3CB2, BLBP expression, and cell proliferation after experimental SCI.
Impact lesions were applied via Infinite-Horizon-Impactor. Controls received laminectomy without lesion (n=10). Rats were sacrificed 2d (n=5), 7d (n=5), 14d (n=5), and 42d (n=5) after SCI. Immunohistochemistry (IHC) and real time RT-PCR was performed for CCL2/CCR2, CCL3/CCR1, SDF-1/CXCR4. Double IHC with cell markers for astrocytes (GFAP), microglia (CD11b), macrophages (ED-1), oligodendroglia (CNPase), neurons (MAP-2, NF150), early developed cells (Nestin), and radial glia (BLBP; 3CB2) were performed. NG2 was used as a progenitor marker. BrdU labelling was performed and quantified for each time-point.
In the white matter CCL2/CCL3 were induced on post-operative day (DPO) 7, peaking on DPO 42, co-expressing 3CB2, BLBP, Nestin and partially GFAP. Their receptors were induced during the later time-course co-expressing mainly 3CB2 and BLBP. SDF-1 was induced on DPO 7 peaking on DPO 14 and co-expressing GFAP and CNPase. CXCR4 was induced on DPO 14 and 42, co-expressing mainly GFAP. After SCI BrdU labelling significantly increased in the white matter compared to control animals. BrdU was co-expressed predominantly with NG2.
Chemokines/-receptors exhibited individual time-dependent expression patterns after SCI. Especially CCL3/CCR1 and CCL2/CCR2 were co-expressed in radial glia and co-localized with proliferating NG2+ cells in the white matter precursor niche making them promising candidates for further investigations.
