Scientists will be able to mimic the effects of heart disease in a petri dish after identifying a new, reliable way to produce heart cells in the lab. New research published in the journal Nature Methods shows how human heart cells can be consistently produced from embryonic stem cells, creating a potentially inexhaustible source for research and drug discovery. Researchers were able to isolate the heart cells by turning them green, says David Elliot of Monash University, who co-led the work.