INDUCTION OF ANTI-PNEUMOCOCCAL CELL-WALL POLYSACCHARIDE ANTIBODIES BYTYPE-4 PNEUMOCOCCAL POLYSACCHARIDE-PROTEIN CONJUGATES

We have prepared polysaccharide-protein conjugates consisting of type 4 pneumococcal capsular polysaccharide (PS4) coupled to tetanus toxoid . The PS4 preparation used contained 2.5% pneumococcal cell wall polys accharide (CPs). During the conjugation process, in addition to PS4-pr otein conjugates, CPs-protein conjugates were also formed. After immun ization with PS4-protein conjugates, CPs-protein conjugates that are p resent as a contaminant induce IgG anti-CPs antibodies in mice. Pneumo coccal oligosaccharides, prepared by periodate oxidation of PS4, did n ot contain detectable amounts of CPs; hence, oligosaccharide-protein c onjugates did not induce anti-CPs antibodies.