Migration Assays for Oligodendrocyte Precursor Cells - Methods in Molecular Biology: Extracellular Matrix Protocols - page 253

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Migration Assays
for Oligodendrocyte Precursor Cells
Emma E. Frost, Richard Milner, and Charles ffrench-Constant
1. Introduction
In the developing central nervous system (CNS), oligodendrocyte precursor
cells (OPCs) originate in discreet regions, which may be at a significant dis-
tance from their final position. These cells must, therefore, undergo extensive
migration in order to reach this final destination (1) . The regulation of OPC
migration remains to be fully elucidated, with the role of external factors such
as extracellular matrix proteins, and growth factors, as well as cell-cell inter-
actions with other neural cells currently being investigated. In order to assess
the possible regulation of OPC migration, we have refined two separate assays
that present the OPCs with putative regulatory molecules in different forms.
First, a modified Boyden chamber, used to analyze directed migration of
cells, and the role of haptotactic, as well as chemotactic stimuli, and their
potential synergy, in regulating OPC migration ( see refs. 2 and 3 ). In this assay,
cells migrate through pores in a filter, from an upper chamber containing a
high concentration of cells, to a lower chamber containing a soluble
chemoattractant. In addition the filter can be coated on the lower surface and in
the pores to form a haptotactic gradient. Second, an agarose drop assay (origi-
nally described by Varani et al. 1978 [4] ) in which cells migrate away from a
small drop containing a high concentration of cells, over an appropriate sub-
strate. In this assay cell migration is driven by the innate motility of the cells
and the high concentration of cells in the drop, and allows the analysis of
chemokinetic or random migration, in the presence or absence of haptotactic
stimuli or growth factors, ( see refs. 5 and 6 ).