Attempts to Cultivate Vaccine Virus in the Growing Chick Embryo.

Abstract

The propagation of vaccine virus in the skin and cornea of susceptible animals has been supplemented by evidence of mass growth in the testicle (Noguchi 1 ) and perhaps the brain (Levaditi 2 ). Attempts to cultivate vaccine virus elsewhere than in the skin of living animals have as their objectives purification of the virus, the production of larger amounts at less cost as well as to throw light on the nature of the virus itself.

These objectives would all be reached and extended if it were possible to grow vaccine virus outside the animal body in ordinary or in tissue culture. It is the generally accepted opinion that viruses in general will increase only in the presence of living cells (Rivers, p. 13 3 ) for which they have specific affinity.

The claims of Fornet 4 and of Volpino 5 of having grown vaccine virus in serum in the presence of sugar or glycerine have not been confirmed. The addition of animal tissue to such media with positive results in the hands of Pröscher 6 and of Plotz 7 has not only been unconfirmed but is denied by Gins. 8 The remarkable results recently claimed by Maitland and Maitland, 9 who apparently obtained marked increase of the virus in a series of cultures comprising minced hen kidney, hen serum and Tyrode's solution, and grown aerobically certainly inspire repetition.

Distinct evidence of the growth of vaccine virus in tissue cultures of adult corneal epithelium (Steinhardt, Israel and Lambert 10 ; Gins 11 ) and in testicular extract (Flores Cordova 12 ) or testicular cells (Parker 13 ; Parker and Nye 14 ; Minervin and Schmerling 15 ; Haagen 16 ) has been generally accepted. Even more interesting positive results in tissue culture with embryonic rabbit and guinea pig cornea were obtained by Cracium and Oppenheimer.