PA5 hOMCs phenotype and promotion of neuron outgrowth after growth on Plastic and Plastic Plus microcarrier suspension culture
RT-qPCR results (Figure 4 A and B), show the upregulation of several markers for PA5 hOMCs grown on Plastic Plus compared to cells at day 0. Fibronectin (3.5-fold), β-III tubulin (2.3-fold), KDR1 (2.9-fold) and Sox9 (2.9-fold) are upregulated for PA5 hOMCs grown on Plastic Plus microcarriers compared to PA5 hOMCs grown on Plastic microcarriers by day 7. Most importantly, p75NTR, a neurotrophic marker expressed by OECs is expressed 2.3-fold more on day 7 by PA5 hOMCs grown on Plastic Plus microcarriers compared with cells on day 0, while PA5 hOMCS grown on Plastic microcarriers maintained the same level of expression of this marker (1.0-fold) (p<0.05). Furthermore, a co-culture assay with NG108-15 cells was used as an assay indicative of the capacity of PA5 hOMCs to promote neurite outgrowth, using F7 Schwan cells as positive control and NG108-15 cell only as a negative control. Representative images used to quantify neurite outgrowth are shown in Figure 4 C. The average neurite length was 36±1.3 µm for Plastic Plus microcarriers, significantly higher (p<0.05) than the average neurite length obtained for Plastic (29.1±1.5 µm) microcarriers and the positive control (27.9±0.1 µm) (Figure 4 D). The maximum neurite length obtained for Plastic Plus was 96±7.0 µm, significantly higher (p<0.05) than the maximum neurite length obtained for Plastic microcarriers (81.8±3.2 µm) and the positive control (57.9±3.3 µm) (Figure 4 E). The average neurite per neuron was of 0.38±0.05, significantly higher (p<0.05) than the one obtained for cells grown on Plastic microcarriers (0.23±0.02) and the positive control (0.22±0.04) (Figure 4 F).