New Discoveries by Cohn Reveal Wonders of Blood

When a physician from the National Association of Military Surgeons was shown through the laboratory of the Medical School's Department of Physical Chemistry several months ago, he came out saying to friends, "As you progress from room to room, you almost expect that in the next one they will be making a jeep out of blood."

He was referring, of course, to the now world-famous experiments of Edwin J. Cohn '17, head of the Department of Physical Chemistry, who has led the way in one of Harvard's most conspicuous contributions to the war. Professor Cohn has discovered to date 20 unknown substances in human blood which have opened new vistas in plastics and military medicine.

Discovers Synthetic Membrane

Ranging from albumen to measles globulin, Professor Cohn's already long list of extractions has only recently been enlarged by two new ones, a synthetic membrane or skin used in treating burns, and a dark brown substance, with possibilities in medical use just beginning to be explored.

If one pictures a human red blood corpuscle to be the size of Soldiers Field, he can get an idea of the tremendous proportions of the task of separating human blood plasma. Remove the red and white corpuscles from the blood, and one has the plasma, composed of water and protein. Even the biggest of these protein particles would be only the length of a man's walking stick in the Harvard Stadium. At that size it would be a particle of fibrinogen, the protein which causes blood to clot and which is used in the new cures for bleeding.

Possibilities Limitless

Professor Cohn is convinced that there is no limit now in sight to the other fractions of plasma that can be used. Cohn had studied the proteins of plasma for many years when he was asked by the Office of Scientific Research and Development in 1940 to further advance his exploration. Since then, seven unique plasma fractionation plants have been built throughout the United States in collaboration with the Navy.

With the constant support of the Red Cross and the National Research Council, Cohn's researches have been an integral part of the Navy's plasma fractionation program. Actually, they are the program, since the navy from the start vested complete authority in the technological and industrial fields in Professor Cohn. Cohn is never quoted, but his colleagues say that "the number of components that may be identified remains far greater than the number of fractions that it has been convenient to separate.