Active Immunization in Human Cases with the Polysaccharide of Pneumococcus Type I

Abstract

Tillett and Francis 1 , 2 showed that patients suffering with pneumonia who were injected intracutaneously with small amounts of pneumococcus polysaccharide of the homologous and heterologous types, showed after some time antibodies not only against the infecting type of organism but against the other types. In explanation they suggested that probably the injections of the heterologous polysaccharides produced antibodies.

Finland and Sutliff 3 confirmed these findings and in addition 4 showed in humans with histories free of recent infection antibody production following the intracutaneous injection of protein-free type specific polysaccharides of either Type I, II, or III Pneumo-cocei.

The present study deals with antibody response following intracutaneous injection of a type specific polysaccharide of Pneumococ-cus Type I prepared according to the method of Heidelberger, Sia and Kendall. 5 Using the same dose as that used by Tillett and Francis 1 in their work on cutaneous reaction to pneumococcus polysaccharides during lobar pneumonia, 0.1 ce. of a 1:10,000 dilution or 0.01 mg., 10 normal human subjects without recent infection were given 5 weekly intradermal injections of Pneumococcus Type I polysaccharide SSS Pn. I F. The cutaneous reactions varied greatly in intensity in different individuals, positive reactions being elicited in a percentage of these subjects contrary to the findings of the aforementioned workers, who observed positive reaction with very few exceptions only in pneumonia patients at time of crisis and after. Maximum reaction consisted of a bright rash-like erythema 40×50 mm. with pseudopods and itching, appearing within 5 to 15 minutes of injection and followed by marked swelling and tenderness and a central area of redness, reaching its height within 2 hours and gradually diminishing. Intermediate reactions were those of varying degree of erythema and wheal formation and finally clear-cut negative results were observed.