Studies on the Nature of the Viricidal Antibodies in Anti-Poliomyelitis Serum. ∗

Abstract

That poliomyelitis convalescent serum, whether of human or monkey origin, possesses viricidal properties demonstrable in vitro is a well established fact (Levaditi and Landsteiner, 1 Flexner and Lewis, 2 Netter and Levaditi, 3 and many others). The nature of the antibodies responsible for the inactivation of the virus has not been determined. While the results of several investigators (Lebredo and Recio, 4 Neustaedter and Banzhaf 5 ) suggest that they may be cytolytic or bactericidal (complement fixing) in nature, others (Wollstein, 6 Gay and Lucas, 7 Römer and Joseph 8 ) have been entirely unable to elicit evidence of specific antibodies of this type. Because of the difference in the results reported, particularly when considered in the light of the ultrafiltrable nature of the virus (Krueger and Schultz 9 ), a careful study has been undertaken to determine, if possible, the exact nature of the antibodies formed against this virus. The work has been carried out with both human and monkey convalescent serum.

No difficulty has been experienced in demonstrating viricidal antibodies in convalescent sera tested in vitro in the customary manner. No evidence of the presence of specific complement fixing and precipitating antibodies for the virus could, however, be elicited in any of these sera. These results harmonize with those in earlier work on vaccinia, rabies, herpes and the bacteriophage (Schultz et al 10 ). To determine further the relationship of the antibodies responsible for the inactivation of the virus, tests were carried out to determine whether neutral serum-virus mixtures are dissociable, and whether time is a factor in the inactivation of virus by immune serum. The results have been in the affirmative.