DIFFERENTIATION OF OLIGODENDROCYTE OCCURS IN CONTACT WITH ASTROCYTE

We have generated stage-specific oligodendrocytes, which are identifie d as immature oligodendrocytes by the expression of specific markers. These cells were generated by using 3 types of intrinsic and extrinsic factors for influencing the characteristics of oligodendrocyte-lineag e cells, The factors included 10% serum in the medium to induce cell p roliferation, bFGF in serum-free medium to increase survival and induc e differentiation, and 0.25% trypsin to remove nonoligo dendrocyte lin eage cells. We have also demonstrated that it is possible to supply a huge amount of homogeneous populations of stage-specific immature olig odendrocytes after 35 days' culture. The maturation of these cells is controlled by interacting with astrocytes in vitro, resulting in the e xpression of MBP isoforms (14.0 and 18.5 kDa) that may participate in mature oligodendrocyte membrane compaction. (C) 1998 Wiley-Liss, Inc.