Differentiation of bipotential glial precursors into oligodendrocytes is promoted by interaction with type-1 astrocytes in cerebellar cultures.

Abstract

The differentiation of bipotential precursors of oligodendrocytes (OL) and type-2 astrocytes (AS) was followed in primary cultures from 8-day postnatal rat cerebellum by labeling the cells with the antibodies LB1 (which binds to the surface disialoganglioside GD3 present in glial precur- "neuron-like" fashion (6,11), are sensitive to kainic acid (V. Gallo, R. Suergiu, C. Giovannini, and G.L., unpublished data), and express chondroitin sulfate (7). The bipotential cerebellar glial precursors pass through four distinct developmental stages during their differentiation into OL in serum-free cerebellar cultures (9). In the first stage, the cells are A2B5+ and LB1'. In the second stage, they can be stained also by the mAb 04, which binds to surface sulfatides and recognizes both immature and mature OL (12). In the third, short-lasting stage, the cells express on their surface also the well-established marker of OL, GalCer (13). In the fourth stage, however, the antigens recognized by A2B5 and LB1 are no longer detectable, and the cells remain positive for 04 and GalCer. Upon addition of FCS, the precursors maintain their ability to differentiate into type-2 AS until they are in the A2B5/LB1/04-positive stage (9). The factors responsible for the choice of the differentiation route taken by the precursor cells have not been defined. It (4,6) were resuspended in Eagle's basal medium (BME, GIBCO) supplemented with 2 mM glutamine, gentamycin (Sigma) at 0.1 mg/ml, and 10% heat-inactivated FCS (different batches from GIBCO); were seeded at 1 x 105 (low density) or 2.5 x 105 (high density) cells per cm2 onto

The inhibition of oligodendrocytic differentiation of O‐2A progenitors caused by basic fibroblast growth factor is overridden by astrocytes

“…These experiments demonstrated that the addition of a single dose of ACM, together with daily additions of 10 ng/ml of bFGF, was associated with a greater extent of oligodendrocytic differentiation after 3 days that was seen with the addition of just 0.03 ng/ml daily of bFGF alone to similar cultures of cells. It therefore seems likely to us that one aspect of the effect of astrocytes is to actively promote the differentiation of 0-2A progenitors into oligodendrocytes, as has also been suggested by other authors (Aloisi et al, 1988;Dutly and Schwab, 1991). Although it has been suggested (Dutly and Schwab, 1991) that such an effect might be mediated by insulin-like growth factor I (IGF-I), recent studies (Barres et al, 1992) have suggested that the effects on 0-2A progenitor differentiation attributed to this protein (McMorris et al, 1986) may have been due to the ability of IGF-I to promote the survival of oligodendrocytes.…”

Developmental appearance, antigenic profile, and proliferation of glial cells of the human embryonic spinal cord: An immunocytochemical study using dissociated cultured cells

“…In particular, bipotential progenitors already expressing the early oligodendroglial marker 0 4 could be largely induced to differentiate into astrocytes under the influence of GFAP-inducing serum factors (Aloisi et al, 1988;Levi et al, 1987;Trotter and Schachner, 1989). The limited number and the transient detectability of 04+/GFAP+ cells in our cultures did not allow us to establish whether these cells would eventually give rise to astrocytes or to oligodendrocytes.…”

Directed establishment of rat brain cell lines with the phenotypic characteristics of type 1 astrocytes.

“…One report (23) does describe the use of a retroviral vector carrying a temperature-sensitive mutant of the SV40 large-T-antigen gene to establish a cell line (SF11) from mouse brain that stably expresses GFAP. However, isolation of the GFAP-expressing line was a rare event (1 out of 19), and the line itself was not examined for other characteristics of type 1 astrocytes.…”

“…These are differentiated cells defined by specific morphological and phenotypic marker criteria (17). Cultures of type 1 astrocytes can be partially purified from other cell types by mechanical and/or immunological techniques (18,19). However, such cultures are still clearly heterogeneous (9,(13)(14)(15) and may not be the most useful model for investigations of functionally specialized astrocyte subsets.…”