Cultivation of the Virus of Common Cold and Its Inoculation in Human Subjects

Abstract

In a series of papers Dochez 1 and his associates have presented evidence for the virus etiology of the common cold and have described experiments on the cultivation of this virus in tissue media and its inoculation into human subjects and chimpanzees. The purpose of this investigation has been to cultivate the virus of common cold and during the period of the year when the incidence of common colds is low to conduct human inoculation experiments on volunteers not subject to isolation.

The strain of common cold virus employed in these experiments was derived from a patient, “A. R.,” suffering from a cold of more than usual severity. Nasal washings were obtained on March 26th, 1931, within the first 24 hours of the onset of the cold. Ten cc. of Tyrode solution were flushed through each nostril and expelled through the mouth. These washings were promptly passed through a Seitz filter and cysteine hydrochloride added to a concentration of 1:2000. The filtered washings were introduced in 1 cc. amounts into 9 cc. hashed chick embryo tissue culture medium containing cysteine hydrochloride in a concentration of 1:2000. The culture was incubated under vaseline seal at 37°C. for 4 days. A Seitz filtrate was prepared from this first culture generation and stored under vaseline seal at 4°C. Further tissue cultures and filtrates were prepared in series as described above, the periods of incubation being from 4 to 5 days and the intermediate periods of ice-box storage of the Seitz filtrate averaging 5 to 6 days. At the present time this cold virus is in the 31st generation and has been cultivated successfully outside the body for a period of 8 months.

Attempts to induce common colds by inoculation into human volunteer subjects were carried out as follows :