Jules Bordet

Earning his medical degree from the Université Libre de Bruxelles, Bordet worked at the Pasteur Institute in Paris under Élie Metchnikoff. In 1895, he discovered that blood serum contains two distinct anti-bacterial factors: heat-stable specific antibodies and a heat-sensitive non-specific component he named 'alexine' (now known as complement).

In 1901, Bordet founded the Pasteur Institute of Brussels. In 1906, together with Octave Gengou, he isolated the bacterium causing whooping cough (Bordetella pertussis) and developed the complement fixation test that became the basis for the Wassermann syphilis test.