Skin Sensitivity and Antibody Production upon Administration of Normal and Immune Serum in Rabbits

Abstract

In studies upon the antibody response in human subjects following administration of serum, Tuft and Ramsdell 1 , 2 have noted that normal serum is weakly antigenic and immune serum highly antigenic, as indicated in tests made for precipitins, skin sensitivity, anaphylactic antibodies and transferable human and guinea pig skin sensitizing antibodies. Administration of normal horse serum was followed by serum sickness however, identical in its clinical characteristics and about as frequently as was produced by the injection of immune serum.

Since it is possible to produce in the rabbit, upon injection of a single large dose of normal or immune serum, a condition closely resembling or identical with serum sickness in man, 3 an attempt was made to compare the antigenicity (as measured by precipitin response and appearance of skin sensitivity) of normal horse serum with that of immune serum, as produced by a single subscapular injection in this species. Three animals were injected with pooled normal horse serum, 5 with the pseudoglobulin fraction of this normal horse serum, 3 with immune serum (collected from the same horses after immunization with diphtheria toxin and containing 1700 units of diphtheria antitoxin per cc.) and 5 with the pseudoglobulin fraction derived from this immune serum. Serum sickness occurred only in some of the animals receiving 75 mg. or more of serum nitrogen per kilo of body weight, and with about the same incidence and severity in those receiving normal serum as in those receiving immune serum. Skin sensitivity and precipitin production resulting from these injections are given in Table I. Skin tests were made by intradermal injection of 0.1 cc. amounts of various dilutions of normal and immune sera or the pseudoglobulin fractions of these sera in the cases of those animals receiving a single large dose of pseudoglobulin fraction. Tests were made for precipitin content of rabbit serum against normal and immune horse sera, or their pseudoglobulin fractions in those cases where the animals received a single large dose of pseudoglobulin.

The results indicate that under these conditions skin sensitivity and precipitin production occur in the rabbit and to practically the same extent whether normal or immune serum is used as the antigen.