[Study of protective activity of Streptococcus pneumoniae protein-containing antigen complex in homologous system].

Aim: Study protective activity of S. pneumoniae protein-containing antigen complex obtained from T3No.3 strain against infection by homologous pneumococcus strain.
Materials and Methods: S. pneumoniae T3No.3 (serotype 3) strain obtained from collection of pneumococcus strains of Mechnikov Research Institute of Vaccines and Sera was used in the study. S. pneumoniae protein-containing antigen complex was isolated by precipitation by 2 volumes of acetone of supernatant fraction of cultural medium used for pneumococcus cultivation. Molecular mass of proteins contained in S. pneumoniae antigen complex was determined by SDS electrophoresis in polyacrylamide gel. Protective activity of S. pneumoniae protein-containing antigen complex was studied in BALB/c line mice active protection experiments. Activity of mice immune sera obtained against whole-cell pneumococcus culture (T3No.3 strain) was determined in vitro by solid phase indirect EIA.
Results: The data obtained give evidence that the isolated protein-containing antigen complex from S. pneumoniae T3No.3 strain effectively protects mice from consequent infection by a homologous S. pneumoniae strain. S. pneumoniae protein-containing antigen complex sorbed on solid phase at 5 microg dose was established by using EIA to interact with homologous mice immune sera.
Conclusion: The results of the carried out studies allow to move to studies of cross-activity of S. pneumoniae protein-containing antigen complex isolated from T3No.3 strain.