Vitamin-C Inhibition of Agglutinin Production

In a previous paper it was shown that ascorbic acid added to or injected simultaneously with horse serum hastens and augments specific-precipitin production in rabbits. A 10- to 30-fold increase in precipitin-titer is readily produced by optimal doses (about 50 mg) of this enzyme-activator. We have extended the study of the potentiating action of ascorbic acid to other antigens. The present paper summarizes our experimental data with bacterial vaccines and sheep erythrocytes (Forssmann antigen).

About 200 two kg rabbits were divided into groups of 6. Each group was injected intravenously with an arbitrary dose of sheep erythrocytes, or of living, heat-killed or formalin-killed suspensions of B. proteus, B. coli or B. typhosus. One minute after each injection, 3 members of each group were given an intravenous injection with 50 mg ascorbic acid dissolved in 1 cc NaCl-solution.

Very low antibody-titers were obtained as a result of these single injections. Within the limits of the experimental error ascorbic acid had only border-line effects on antibody-yield, except on the yield of specific agglutinin. In 3 groups injected with B. typhosus, for example, the yield of specific agglutinins was reduced about 50%.

In order to magnify these border-line effects, additional groups of 6 rabbits were given from 7 to 13 multiple injections with the same antigens, followed in half of the members of each group by our routine therapeutic dose (50 mg) of ascorbic acid. In addition to the erythrocytes and bacterial vaccines above tested, 3 groups of rabbits were injected with partially autolysed or'phage-lysed B. typhosus and 2 groups with staphylococcal proteins obtained by grinding staphylococci in a ball-mill. For the staphylococcal proteins used in these tests we are indebted to Dr. A. P. Krueger, of the University of California. Typical data from these multiple injections are recorded in Table I.