29-07-08(22:08:20)
Authors:
Ferreira, I 1
Pawar, K 1
Mueller, R 2
Rivera, F 1
Caioni, M 1
Weidner, N 1
Weidner, N
Institutions:
1 Department of Neurology, University of Regensburg, Germany
2 Institute of Physical and Theoretical Chemistry, University of Regensburg, Regensburg, Germany
Title of abstract : Combining alginate-based anisotropic hydrogels and adult neural progenitor cells for spinal cord repair
Abstract text:
The injured spinal cord lacks the intrinsic capacity to regenerate its highly organized architecture essential for structural and functional recovery. We previously reported that alginate-based anisotropic capillary hydrogels (ACH) provide physical guidance thus promoting longitudinally directed axonal regrowth after spinal cord injury. The aim of the present study is to further enhance axonal regrowth into ACH by introducing cells as a “biological link” between the regrowing axon and the ACH.
Adult rat derived neural progenitor cells (NPC) were seeded on top of vertically oriented ACH and kept for 7 days in culture in either EGF/FGF-2 containing proliferation medium or 10% fetal calf serum containing differentiation medium. ACH with 3 different capillary diameters ranging from 35 to 120 μm, with and without surface modification by adding gelatine, were chosen. Seeded NPC were identified by progenitor cell marker (nestin, A2B5) or marker for mature glial cells (GFAP for astroglia, MBP for oligodendroglia) visualized with immunocytochemistry and fluorescence microscopy.
In proliferation condition, seeded NPC are found within the entire capillary length in all types of ACH expressing mainly A2B5. In differentiation condition, seeded NPC displaying oligodendroglial differentiation are detectable within ACH with small capillary diameters, whereas GFAP expressing astroglial cells are found predominantly outside of the ACH extending long processes into the capillaries. In contrast, within 120 μm ACH, both astroglial and oligodendroglial cells align along the entire capillary extent. Surface modification with gelatine appears to promote oligodendroglia differentiation. Taken together, the modification of structure and surface of biomaterials affects NPC differentiation.
