Protective activity of a glycoconjugate based on a synthetic hexasaccharide related to a fragment of capsular Streptococcus pneumoniae serotype 14 polysaccharide chain.

We studied the effects of immunization with a conjugate of carrier protein and hexasaccharide ligand related to a fragment of capsular of Str. pneumoniae serotype 14 polysaccharide chain on activation of innate and adaptive immunity. It was found that two-fold immunization with the glycoconjugate adsorbed on aluminum hydroxide significantly increased the titer of IgG antibodies to capsular polysaccharide in the blood and protected 100% mice from infection with Str. pneumoniae serotype 14. Enhanced bactericidal activity of peripheral blood lymphocytes of mice was found 4 and 24 h after the first immunization with the immobilized glycoconjugate. Adsorption of the glycoconjugate on aluminum hydroxide resulted in modification of the immune processes at the stage of activation of innate immunity and subsequent strengthening of the adaptive immunity.