Inhibition of antibody formation by receptor cross‐linking: the molecular characteristics of inhibitory haptenated polymers

Previous studies from this laboratory have reported on the characteristics of a molecule which make it inhibitory. These findings were based on studies using the T cell‐independent haptenated polymer, 2,4‐dinitrophenyl‐polyacrylamide (DNP‐PA). The present study was undertaken to determine whether the same molecular properties which defined the inhibitory potentials of DNP‐PA were characteristic of other haptenated polymers as well. The molecules studied here consisted of a series of five diverse fluoresceinated polymers with varying molecular mass and hapten valence. In agreement with the previous findings on DNP‐PA, definable molecular forms of fluoresceinated dextrans, Ficolls, polyacrylamides, carboxymethyl celluloses and polyvinyl alcohols were each found to be capable of inhibiting the anti‐fluorescein response to immunogenic forms of haptenated polymers of either the same or different carrier chemistry. This inhibitory ability was relatively independent of the chemical composition and conformation of the carrier polymer. These studies allow some logical generalizations to be made as to which quantitative molecular properties of haptenated type 2 T cell‐independent antigens determine whether they will be stimulatory or inhibitory of an anti‐hapten immune response.