Immune Characterisation of Human Local Pneumotropic Isolates of Streptococcus pneumoniae Serotype 1 and 6 as Local Vaccine Strains

Abstract

pneumoniae is one of the principle human pneumopathogen. Such pathogenicity features in man can be delineated by severity, capsule nature and yield of pure growth onto primary plate cultures. While in laboratory animal models, it accounts for; the nature of capsule serotype, shortness of time for the death end point and extent of tissue pathology. The virulent serotypes C1 and C 6 of human pneumotropic S. pneumoniae were immune characterized as vaccine strains. Capsules were separated, identified and quantified. Then dispensed as 10mg deried amounts in ampoules. On reaching specific immune priming of rabbits the ampoules dissolved in 10 mls sterile saline and each ml admixed with 1ml lanoline and injected intramuscularly per each rabbit's thigh muscles. The immune primed rabbits left for 28 days then test bleed to check for an evident immune conversion then, at the day 35 after immunization the immune rabbits were challenged with live S. pneumoniae 1x 10 to six CFU/ml., in a rate of 2 mls. The carbohydrate based capsule prototype monvalent vaccines were found as; Pure, safe, antigenic, immunogenic and immune protective to the rat of 80% for C1 and 60% for C6 serotype in rabbit models. They induced systemic humoral immune precipitins responses higher than mucosal pricipitin responses. Proinflammatory cytokine responses TNF alpha, TNF beta and IL6 and anti-inflammatory cytokine IL10 were mounted as mucosal responses higher than the systemic responses. The proved immune characteristics of these capsule serotypes were suggestive for use of these strain as vaccine strains along with other serotypes in development of the local prototype multiserotype vaccines of this pathogen.