An amended history of tissue culture: Concerning Harrison, Burrows, Mall, and Carrel.

The origin of tissue culture is commonly dated to 1907 and credited to Ross Harrison at Hopkins Medical School. But an unpublished letter from the 1942 offers a different interpretation and gives priority to Montrose Burrows with important contributions for the development of cell culture by Franklin Mall at Hopkins and Alexis Carrel at the Rockefeller Institute in New York City. The early development of tissue culture is reviewed and its applications in modern biology and medicine are briefly outlined.