A Poliomyelitis Antiserum. ∗

Abstract

A normal sheep was bled, and no neutralizing antibodies for poliomyelitis virus were found in the blood serum in 1:1 dilutions. The animal was then injected as follows: September 8, 12, 17, and 24, 1934, 10 cc. of a suspension of equal parts of 2% poliomyelitis virus and P.C.B. filtrate intradermally; 1 October 1st and 8th, 30 cc. of a suspension of equal parts of a 2% virus combined with P.C.B. filtrate subcutaneously; October 13th, 40 cc. of a suspension made up of equal parts of a 5% virus combined with P.C.B. filtrate subcutaneously; October 23rd, November 8th and 20th, and December 8th, 50 cc. of a suspension made up of equal parts of 5% virus combined with P.C.B. filtrate subcutaneously and intramuscularly. On September 13th, there was some local induration about the injection, and on September 15th, there was a small localized abscess.

Although there was still evidence of local induration about the last injection, the animal was bled on November 20th and the serum tested. It was found that this serum, obtained only 12 days after an injection of the virus and filtrate combination, acted as an accelerator, since the disease was produced in the test animal in 3 days, and in the control in 7 days. That the serum was tested too soon after the injection was obvious from later results. The animal was not bled again until January 18, 1935, at a time when no external evidence of reaction was found in the skin or in the area over the muscles where the injections had been made.

The sheep serum was inactivated at 56°C. for 1 hour. In these experiments, the injections were all made intracerebrally under complete ether anesthesia.