The effects of immunization to L-asparaginase on antitumor and enzymatic activity.

摘要: Summary BALB/c mice were immunized with Escherichia coli l-asparaginase and tested for the presence of hemagglutination antibody (HA) to enzyme. Mice then grouped according whether they immune (HA titer, >4) or non-HA responders (negative HA titer). In vivo antitumor activity against P-1798 (an l-asparaginase-sensitive lymphoma) was in both groups, as well control (never before exposed l-asparaginase). l-Asparaginase inactive tumor but equally active animals. Another experiment compared derived from E. enzyme Erwinia carotovora (which does not cross-react immunologically received about same benefit did mice. separate studies, blood samples immune, responder, by vitro assays levels l-asparagine at various time intervals up 120 hr following a single i.v. injection l-asparaginase. Most cleared plasma 30 min after consequently had rapid return circulation l-asparagine. animals, detectable over 48 injection, remained absent circulation. These studies relate humoral loss enzymatic suggest that, animals without HA, is intact.