Charles Philippe Leblond


Charles Philippe Leblond : biography

February 5, 1910 – April 10, 2007


Early days

CP Leblond was born in Lille, France, in 1910, the son of a building contractor who died when Leblond was only 10 years old, leaving his mother to raise four boys on her own. A brilliant student, Leblond debated becoming a film producer, an architect or a scientist. In the end, he decided on science, and enrolled in Medicine at the University of Paris. He was fascinated by his first course in histology and decided to pursue this field as a career.

Leblond obtained his M.D. degree from the University of Paris in 1934. His doctoral thesis described the histochemical localizion of ascorbic acid, which he found to predominate in steroid-secreting cells.A. Giroud et C.P. Leblond. Etude histochimique de la vitamine C dans la glande surrénale. Arch. Anat. microse. 1934, 30, 105 129. This study led him, with a Rockefeller postdoctoral fellowship in hand, to the endocrinology-orientated Department of Anatomy at Yale University in 1935, where he carried out studies on factors influencing maternal behavior..C.P. Leblond. Extra hormonal factors in maternal behavior. Proc. Soc. Exp. Biol. Med. 1938, 38, 66 70. It was here that he met his wife Gertrude Sternschus, to whom he was married for 64 years.

In 1937, Leblond joined the Laboratoire de Synthese Atomique in Paris which was involved in preparing radioactive isotopes for use in investigating the fate of various molecules in biological processes. Under the guidance of Antoine Lacassagne, Leblond injected radioiodine-128, into a rat and found that the label promptly accumulated in the thyroid gland, presumably incorporated into the thyroid hormone precursor thyroglobulin.C.P. Leblond et P. Sue. Passage de l’iode radioactif (1128) dans la thyroide stimulée par l’hormone thyréotrope de l’hypophyse. C.R. Soc. Biol. 1940, 133, 543. To localize this label more precisely within the thyroid tissue, Leblond attempted to use the novel technique of autoradiography.

Unfortunately, Leblond’s first attempt to use autoradiography failed, the reason being that the radioiodine-128 isotope, with its extremely short half-life (25 minutes), disintegrated so quickly that too little radioactivity remained to be detected by the photographic emulsion.

Development of autoradiography

In 1941, Leblond moved to McGill University as a lecturer in histology, and quickly rose to assistant (1943), associate (1946), and then full professor of anatomy (1948). He served as the chair of the Department of Anatomy from 1957–1974.

At McGill, Leblond used the newly-available radioiodine-131 with a half-life of 8 days, to repeat his autoradiographic experiment on thyroid tissue. With this method, the resolving power was less than 100 µm, but nonetheless he was able to localize the radioactivity to specific thyroid [follicles].C.P. Leblond. Extra hormonal factors in maternal behavior. Proc. Soc. Exp. Biol. Med. 1938, 38, 66 70.

Leblond’s early career at McGill was interrupted by World War II, during which he served in the Free French Forces. He was dispatched first to Rio de Janeiro, then to London, where he conducted medical exams of would-be soldiers.

"In 1946, after returning to Montreal from service with the Free French Forces, it was clear to me that the crude technique previously used for radioautography had to be improved".Leblond CP. The time dimension in cell biology. FASEB J. 1995 Sep;9(12): 1234-8. In collaboration with Leonard Bélanger, Leblond worked on increasing the resolution of the autoradiographic technique. They were advised by physicist Pierre Demers to melt the emulsion from Eastman Kodak lantern slides, paint it directly on the sections, and then develop the emulsion while it was still attached to the histologic sections. This resulted in a tenfold improvement in resolution.F. Bélanger and C.P. Leblond. A method for locating radioactive elements in tissues by covering histological sections with a photographic emulsion. Endocrinology 1946, 39, 386 400. Subsequently, Leblond and his colleagues developed a technique in which the histologic slides were dipped directly into liquid emulsion.C.P. Leblond and J. Gross. Thyroglobulin formation in the thyroid follicle visualized by the "coated autograph" technique. Endocrinology 1948, 43, 306 324. The use of thinner sections and emulsion coats led to further advances in resolution, and the introduction of tritium was a technical milestone.