[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.

[Effect of strain-producer and cultivation medium on cross antigenic activity of Streptococcus pneumoniae water soluble antigens].

AIM: Production of water soluble protein-containing antigens from various strains of S. pneumoniae during cultivation in complete and semi-synthetic culture media as well as selection of strains with cross antigenic activity. MATERIALS AND METHODS: S. pneumoniae 3, 6A, 6B, 14, 10A, 18A, 19A, 19F, 23F serotype strains were cultivated in brain-heart broth and semi-synthetic medium with addition of aminopeptide for 24 hours at 37 degrees C for the production of water soluble antigens. The antigens were obtained by a method of triple water extraction from acetone dried microbial cells. Chemical composition of preparations, electrophoresis mobility of protein-containing components of preparations and cross antigenic activity in gel immune diffusion reaction by using rabbit hyperimmune sera were studied. RESULTS: In studies of 10 pneumococcus strains from various serotypes a method of microbial cell inactivation by acetone was selected that allows to produce preparations with high protein content (25.5 - 53.1%). Electrophoretic separation of the preparations revealed difference in the preparations obtained from various pneumococcus strains in the layout of major protein lines in the 8 - 95 kDa range. The most virulent and immunogenic S. pneumoniae strain that during cultivation in semi-synthetic medium was characterized by intraspecies cross antigenic activity and in gel immune diffusion reacted with all the studied sera against 3, 14, 18C, 23F serotype strains was selected. CONCLUSION: The study resulted in the selection of a technologically simple method of production of pneumococcus antigens with high protein content and showed that only 1 of the studied preparations produced from a virulent strain with poorly expressed S. pneumoniae capsule during cultivation in semi-synthetic medium has the highest cross antigenic activity.

[Strain differences of intra-species immunogenic activity of Streptococcus pneumoniae antigen components].

AIM: Study intra-species immunogenic activity of antigenic protein-polysaccharide components of S. pneumoniae. MATERIALS AND METHODS: Antigenic components of serotype 3, 6A, 6B, 14, 10A, 18A, 19A, 19F, 23F and unencapsulated S. pneumoniae strains were obtained by water extraction method. Synthetic hexasaccharide--corresponding to the structure of S. pneumoniae serotype 14 capsule polysaccharide repeated unit chain fragment was used as a reference preparation. Molecular mass of antigenic components was determined in SDS-electrophoresis. Antibody titers in blood sera of immunized mice were evaluated by solid-phase EIA method. Protective activity of preparations was studied in mice after 2 immunizations with consequent infection by virulent S. pneumoniae serotype 3 and 6B strains. RESULTS: Preparations from serotype 6A, 6B, 14, 19A, 19F, 23F strains in reaction with anti-microbial sera were characterized by cross serologic activity (IgG titers of 1200 - 12 800). The lowest serologic activity was detected in S. pneumoniae serotype 3 and unencapsulated strain preparations. Conjugate of synthetic hexasaccharide and bovine serum albumin interacted only with homologous antimicrobial sera up to titers of 600 +/- 89.4 and did not react with sera against serotypes 19A and 19E Cross serologic activity of preparations is probably determined by the presence of protein fractions that were detected in SDS-electrophoresis. This is confirmed by high intra-species cross protective activity of preparations from serotype 6B and 10 A strains that protect 90 - 100% of mice from infection by heterologous S. pneumoniae strains. CONCLUSION: Use of strains with cross antigenic and protective activity for production of immunogenic protein-containing fractions with the aim of enchanting and broadening specter of protective activity of vaccine preparations that are constructed based on capsule polysaccharides of S. pneumoniae is appropriate.

[The reactogenicity and safety of a multicomponent vaccine (VP-4) in the prevention of acute respiratory diseases in preschoolers]. / Reaktogennost' i bezopasnost' polikomponentnoi vaktsiny (VP-4) pri profilaktike ostrykh respiratornykh zabolevanii u doshkol'nikov.

The reactogenicity and safety of poly-component vaccine (VP-4), prepared from the antigens of opportunistic bacteria, in the prophylaxis of acute respiratory diseases (ARD) in children aged 2.6-6 years. The vaccine was administered intranasally in 3 administrations and orally in 6-8 administrations at intervals of 3-4 days for a period of 24 +/- 4 days. The prophylaxis of ARD with the use of VP-4 was carried out in 168 children in 4 children's preschool institutions. The control group was made up of 120 children, attending the same institutions. The study revealed that VP-4 had low reactogenicity and induced short-time systemic and local reactions (common cold, cough). The administration of VP-4 at a period of the epidemic rise on influenza and ARD morbidity did not lead to an increase in the frequency and duration of ARD in the vaccinees, as well as to the exacerbation of chronic infection and the allergization of the body.