re: #57 Timothy Watson

The American Society for Cell Biology indicates that fetal tissue was instrumental in developing the polio vaccine and other research. The NIH also points to fetal tissue as being involved in polio vaccine development.

The 1954 Nobel Prize Award Ceremony Speech also identifies human embryo research contributing to polio vaccine development.

At last, time was ripe for experiments on the poliomyelitis virus. The prospect of a favorable result could not be considered particularly bright. Other scientists had previously attacked the problem with very moderate success. It was generally held that the final word had already been said by Sabin and Olitsky who in 1936 tried to grow the virus in Maitland cultures of various tissues from chick embryos, mice, monkeys, and human embryos. Their results remained completely negative except in cultures of human embryonic brain tissue in which the virus at least seemed to maintain its activity. These findings were taken as a definitive confirmation of the accepted concept of the virus as a strictly neurotropic agent, i.e. capable of multiplying in nerve cells exclusively. Accordingly, the hopes of a practicable method for the cultivation of the poliomyelitis virus were temporarily shelved. Of all tissues, nerve tissue is the most specialized, the most exacting and consequently the most difficult to cultivate. As, at that, there seemed to be no alternative to the use of human brain tissue, the general resignation is easily understood.

In the 1940’s the belief in the neurotropism of the virus began to falter, however, and Enders, Weller and Robbins decided to repeat Sabin and Olitsky’s experiment with an improved technique. In their first experiments they used human embryonic tissue. To the great surprise of everybody except perhaps the experimenters themselves they registered a hit in their first attempt. The virus grew not only in brain tissue but equally well in cells derived from skin, muscle, and intestines. Furthermore, in connection with the multiplication of the virus, typical changes appeared in the cellular structure, finally leading to complete destruction, easily recognizable under the microscope. This observation furnished a convenient method of reading the results. Furthermore, immune serum was found to inhibit specifically the virus multiplication, the technique therefore being applicable also in immunity tests. Subsequently, Enders, Weller and Robbins found that tissues secured from operations on children as well as adults could be used to advantage; all tissues except bone and cartilage seemed to be equally suitable. Finally they tried to isolate the virus from various specimens directly in tissue cultures. This was likewise achieved. In the latter observation probably the greatest practical importance of their discoveries is to be found. The virologists finally had a tool in the same classes the culture technique of the bacteriologists.