Results

Results

After five days of differentiation, around 20% of the embryonic stem (ES) cells differentiated into motor neurons, as demonstrated by the expression of green fluorescent protein (GFP; Fig. 1 – 2). At this point in time, the cells began to leave the cluster (neurosphere) and extend processes outward (Fig. 3 – 5). The shapes and the lengths of the processes vary from cell to cell.

When the ES cells (green) were co-cultured with chick muscle (blue), punctate alpha 1C labeling (red) was seen both within the neurosphere (Fig. 6 – 8) and within the muscle field (Fig. 9 - 14). At least some of this expression appeared to be within the muscle cells themselves (Fig. 12 – 14). The remaining expression (Fig. 9 – 11) may have been in muscle or in migrating cells originating from the neurosphere but which did not express GFP. The localization of the alpha-1 C was best seen when the images were overlaid (Fig.11, 14). There was not much obvious alpha-1 C labeling on the differentiated, green embryonic stem cells, but in Fig. 7 there seemed to be some clustering of alpha-1 C labeling around cell-shaped bodies.

In the control experiment, NCAM labeled the muscle fibres of the chick muscle magnified at 10x, 20x and 40x (Fig. 15 - 17). There was minimal alpha-1 C labeling of the chick muscle. Fig. 18 showed some red, but the labeling in the muscle tissue alone was not in the punctate pattern as seen in the co-cultures.


Figure 1 – ES cell cluster with GFP labeling the cells at 10x.10x, scale bar = 100um	Figure 2 – ES cell cluster with GFP labeling the cells at 20x.

Figure 3 – GFP labels ES cells with extensive processes at 63x. Scale bar is 10um	Figure 4 – GFP labels ES cells with extensive processes at 63x.

Figure 5 – GFP labels ES cells with extensive processes at 63x.	Figure 6 – GFP labels ES cells with processes at 40x.

Figure 7 – Same field position as figure 6; punctate alpha 1C labeling at 40xScale bar is 20um.	Figure 8 – Overlay of figures 6 and 7.

Figure 9 – Chick muscle (co-cultured with ES cells) labeled with NCAM at 63x.	Figure 10 – Same field position as figure 9; punctate alpha 1C labeling at 63x.

Figure 11 – Overlay of figures 9 and 10	Figure 12 – Chick muscle (co-cultured with ES cells) labeled with NCAM at 63x

Figure 13 – Same field position as figure 12; punctate alpha 1C labeling at 63x.	Figure 14 –Overlay of figures 12 and 13.

Figure 15 – Control; chick muscle labeled with NCAM at 10x.	Figure 16 – Control; chick muscle labeled with NCAM at 10x.

Figure 17 – Control; chick muscle labeled with NCAM at 40x.	Figure 18 – Same field position as figure 17; no punctate alpha 1C labeling.Scale bar is 20um.