Restoration of Activity of Neutralized Biologic Agents by Removal of the Antibody with Papain

[摘要] 1. 1. It has been found that proteolytic enzymes such as crystalline pepsin, trypsin, chymotrypsin, and activated crude papain have no effect on the relatively pure coliphage. The failure of the ribonuclease to inactivate it is in accord with the finding that phage contains only 0.07 per cent of phosphorus and, therefore, probably is not a nucleoprotein.2. 2. Trypsin and chymotrypsin have been found to have no effect on phage-antibody.3. 3. Pepsin very slowly, and papain very rapidly, destroy the antiphage.4. 4. When bacteriophage is neutralized (inactivated) by specific antibody, digestion of this antibody by papain restores the phage-activity.5. 5. The length of contact of phage with antibody prior to digestion with papain has been found not to affect reactivation. On the other hand, the amount of antibody combined with phage determines the outcome of attempts at reactivation. If phage-particle is combined with just enough antibody to neutralize it, it can be reactivated, while if the phage is overneutralized it cannot be reactivated by digestion with papain.6. 6. This finding has been explained by the failure of the papain to digest the antibody-molecule completely (as distinct from destroying antibody-function), as indicated by the fact that digested reactivable, as well as unreactivable, mixtures sensitize guinea pigs to rabbit serum, while only the reactivable mixtures stimulate production of antiphage.7. 7. Botulinal toxin neutralized by antitoxin has been reactivated by papain. The resemblance to phage is even more complete in the fact that overneutralized toxin cannot be reactivated.8. 8. Free specific polysaccharide may be obtained from specific floccules by digestion with papain.9. 9. However, pneumococci, even when sensitized with excess of antibody, can infect mice if antibody is digested with papain.10. 10. The reasons for differences in reactivability of the phage- and toxin-systems on one hand and the pneumococcus on the other have been discussed.11. 11. It has been found that digested (unreactivated) overneutralized phage does not elicit the production of antiphage, and this fact is discussed in relation to the possible use of neutralized viruses for immunization.

[学科分类] 生物科学（综合）