TISSUE RECONSTRUCTION FROM DISSOCL\TED CELLS 



215 







' •!# 



4 * 



•x-i-- 



k^'" . &. 





-2J> 







Figure 12. Histological sections through neural-retina cell aggregates compounded of 

 chick embryonic cells (a), mouse embryonic cells (c), and intermingled cells from 

 both (b) . The mouse-cell nuclei are larger and stain darker. 





# 





« 



4 > 





t;*7^'^**^* 



.-»'» 



1.- 





# * 





t 



♦ « b 





<? 



Figure 13. a. Chick cartilage-forming cells; b. mouse cartilage-forming cells; c. section 

 through a composite aggregate, showing chimeric cartilage. 



tested. Cells from two different tissues— one tissue from chick embryos, 

 the other from mouse (heterologous-heterotypic combinations ) —were 

 mixed and compounded in rotating cultures. In all such combinations 

 the cells from each tissue invariably became grouped separately. Al- 

 though in early aggregates the cells were completely interspersed 

 without recognizable order, in 24 hours they were found grouped and 

 arranged in distinct regions. For example, in composite aggregates 

 compounded of chick kidney cells and mouse cartilage-forming cells. 



