"This undated scanning electron micrograph image made available by the National Institutes of Health and National Center for Microscopy in August 2013 shows HeLa cells. The cancerous cells, originally taken from Henrietta Lacks in 1951 without her knowledge or consent, were the first human cells that could be grown indefinitely in a laboratory. These ""HeLa"" cells have been crucial for key developments in such areas as vaccines and cancer treatments. (AP Photo/National Institutes of Health, National Center for Microscopy, Tom Deerinck)"