ANTI-TRINITROPHENYL (TNP) ANTIBODY DETECTION BY NEUTRALIZATION OF TNP-COLIPHAGE T4

Anti-trinitrophenyl antibodies are detected by the specific neutralization of bacteriophage T4 haptenated with the picryl radical (TNP). TNP-phage neutralization by anti-TNP is compared to neutralization by anti-phage. Anti-TNP neutralized haptenated phage by two separable first order processes. The initial reaction was operative until the surviving fraction approached 0·1 at which point a second, slower, apparent first order process was detectable. Neutralization of haptenated phage by anti-phage antibody appeared to proceed by a single first order reaction and thus differed from neutralization by anti-TNP antibody. Neutralization by anti-TNP is hapten specific since anti-hapten antibody was unable to neutralize native phage and since neutralization of TNP-phage by anti-TNP was inhibited by TNP-ε{lunate}-aminocaproic acid which does not affect anti-phage antibodies. Neutralization of TNP-phage by anti-hapten also differs from neutralization of TNP-phage in the rat the former is more dependent on antigen concentration. This assay was used to detect primary 19S and 7S anti-hapten antibodies separated by sucrose gradient centrifugation and provides a means of detecting the two classes of anti-TNP antibodies at very low concentration. © 1969.