Original: Ilya Ilyich Mechnikov ( ) ( also romanized Elie Metchnikoff ) ( 16 May 1845 -- 15 July 1916 ) was a Russian microbiologist best remembered for his pioneering research into the immune system .
Simplified: Ilya Ilyich Mechnikov ( May 16 , 1845 - July 16 , 1916 ) was a Russian biologist .