Aims: Streptococcus pneumoniae is one the world’s foremost bacterial pathogens that cause massive global mortality and morbidity in young children and immunocompromised adults especially in developing countries. Biofilms have been increasingly recognized as an important prerequisite to disease. Individual S. pneumoniae strains differ markedly in their virulence phenotypes, but genetic heterogeneity has complicated attempts to identify any association between a given clonal lineage and propensity to cause a particular disease type. This study investigated serotype 19 S. pneumoniae from blood and ear isolates for biofilm formation capacity in relation to isolate source, pH and ferric oxide [Fe(III)] supplementation. Methodology and results: Viable count and density biofilm assays, microscopy and multi locus sequence typing (MLST) were applied to investigate biofilm formation capacity and genetic diversity of serotype 19 S. pneumoniae from blood and ear isolates. Generally, blood isolates were observed to produce more biofilms at both pH 7.4 and 6.8 compared to the ear isolates. The supplementation of Fe(III) was also found to support biofilm growth. Upon MLST typing of the isolates, marked differences in biofilm formation within the same sequence types (ST) of ST199 and ST177 was observed. This strongly indicated that strains within the same sequence type show differences in biofilm formation capacity. Conclusion, significance and impact of study This study showed that despite belonging to the same serotype, serotype 19, S. pneumoniae blood and ear isolates showed high diversity in biofilm formation ability in relation to pH and Fe(III) supplementation. Additionally, pneumococcal isolates from sequence types ST199 and ST177 also gave rise to differences in biofilm formation ability within the same sequence type (ST). The diversity of biofilm formation within serotype 19 seen in this study is significant to further inform of vaccination strategies against pneumococcal infections, in that due to variations in biofilm formation capacity within the same ST. It is possible that within serotype 19 may show variable vaccination or drug treatment responses. This also indicates that the current treatment strategy which employs specific serotype selection as for PCV14 and PCV7 pneumococcal vaccines may not produce the desired therapeutic results.
Streptococcus pneumoniae--immunology ; Biofilms--radiation effects

Background: Acute lower respiratory tract infection, mainly pneumonia, were the main reasons cause death for children under 5 years old. Objectives: Determine the isolated rate of bacteria inpatients under 5 years old with acute lower respiratory tract infection in Ha Noi and antibiotic resistance of pneumococcal isolated form patients. Subjects and method: Patients under 5 years old with acute lower respiratory tract infection in National hospital of pediatrics and Bach Mai hospital from 01/2002. Using quantitative culturedand PCR method. Results: Out of total 164 patients with lower respiratory tract infection, there were 91 diagnosed pneumonia by chest X-ray, 73 cases of acute bronchitis. 73,6% of the pneumococcal isolated were penicillin resistance (gPRSP) with different genes such as pbp 1a+2x+ab. Most of the S.pneumoniae strains were serotype 19F or 23F. There were no statistic differences by comparison charactersistics of weight, vessel, subclinical symptoms such as: dissolved oxygen level (S\xac\xacp\xac\xac\xac\xacO\xac2\xac), the amount of leucocyte in blood. However, temperature of pneumonia patients was higher than bronchitis patients, breathing of pneumonia patients was also faster than bronchitis patients. Isolated bacteria with amount \ufffd?106 cfu/ml was H.influenzae, S.pneumoniae and Moraxell catarrhalis in pneumonia group, bronchitis group was 28,8% and control group was 17,1%. Conclusion: Penicillin, erythoromycin and co-trimoxazole resistance rate of S.pneumoniaein patients with acute lower respiratory tract infection was high. Quantitative cultured method has prognostic value in diagnosis pneumonia.
Genes ; MDR/ drug effects ; immunology ; Streptococcus pneumoniae/ growth & ; development ; Anti-Bacterial Agents

Antibodies to a capsular polysaccharide (PS) provide protection against Streptococcus pneumoniae which express the homologous capsular serotype, and pneumococcal vaccines are designed to induce antibodies in the capsular PS. Levels and opsonophagocytic capacity of antibodies to the capsular PS of S. pneumoniae serotype 19F were determined by sera from adults immunized with 23-valent S. pneumoniae capsular PS vaccines. Geometric means of IgG anti-19F antibody level and specific opsonic titer rise significantly after immunization. The level of anticapsular PS antibodies for S. pneumoniae 19F serotype is fairly well correlated (r2=O.63) with the opsonophagocytic activities of sera. However, 3.7% (1/27) of serum samples display strikingly less opsonophagocytic activity than expected on the basis of their antibody level. Thus, antibody level may be of general use in predicting vaccine-induced protection among adults for 19F serotype. However, the opsonic activity data suggest that antibody levels are not always indicative of functional antibody.
Adult ; Antibody Formation ; Bacterial Vaccines/immunology* ; Enzyme-Linked Immunosorbent Assay ; Human ; IgG/blood* ; Opsonins/blood* ; Phagocytosis/immunology ; Pneumococcal Infections/prevention & control* ; Pneumococcal Infections/immunology* ; Pneumococcal Vaccines ; Polysaccharides/blood ; Reference Values ; Serotyping ; Streptococcus pneumoniae/immunology ; Streptococcus pneumoniae/classification

OBJECTIVETo compare the sensitivities of two different serotypes of Streptococcus pneumoniae in acute otitis media of C57BL/6 mice.

METHODSThe middle ear cavity of C57BL/6 mice were inoculated via intratympanic injection of Streptococcus pneumoniae TIGR4 or 6B 1×10(8) CFU, and the control group were inoculated equivalent phosphate buffered solution (PBS). The incidence of mice, development of otitis media and the middle ear lavage fluid pathological changes by HE staining, as well as cell counts and cytokine levels were investigated.

RESULTSAfter inoculated with Streptococcus pneumoniae TIGR4, 6B and PBS, the survival rate of 6B group was significantly less than TIGR4 group and PBS control group (P < 0.01). Inflammatory cells in the middle ear cavity were mainly neutrophils, and the inflammatory cells recruitment in TIGR4 group were more than 6B group; The levels of IL-6 and TNF-α in the middle ear lavage fluid in TIGR4 group and 6B group were significantly increased compared with PBS control group, while the TIGR4 group were significantly increased compared with 6B group;6B group had delayed bacterial clearance in the middle ear.

CONCLUSIONThe study implied that Streptococcus pneumoniae 6B had higher pathogenicity for acute otitis media in C57BL/6 mice than TIGR4.

Acute Disease ; Animals ; Cytokines ; immunology ; Female ; Male ; Mice ; Mice, Inbred C57BL ; Otitis Media ; immunology ; microbiology ; Streptococcus pneumoniae ; classification ; pathogenicity

Streptococcus pneumoniae can asymptomatically colonize the nasopharynx and cause a diverse range of illnesses. This clinical spectrum from colonization to invasive pneumococcal disease (IPD) appears to depend on the pneumococcal capsular serotype rather than the genetic background. According to a literature review, serotypes 1, 4, 5, 7F, 8, 12F, 14, 18C, and 19A are more likely to cause IPD. Although serotypes 1 and 19A are the predominant causes of invasive pneumococcal pneumonia, serotype 14 remains one of the most common etiologic agents of non-bacteremic pneumonia in adults, even after 7-valent pneumococcal conjugate vaccine (PCV7) introduction. Serotypes 1, 3, and 19A pneumococci are likely to cause empyema and hemolytic uremic syndrome. Serotype 1 pneumococcal meningitis is prevalent in the African meningitis belt, with a high fatality rate. In contrast to the capsule type, genotype is more closely associated with antibiotic resistance. CC320/271 strains expressing serotype 19A are multidrug-resistant (MDR) and prevalent worldwide in the era of PCV7. Several clones of MDR serotype 6C pneumococci emerged, and a MDR 6D clone (ST282) has been identified in Korea. Since the pneumococcal epidemiology of capsule types varies geographically and temporally, a nationwide serosurveillance system is vital to establishing appropriate vaccination strategies for each country.
Drug Resistance, Multiple, Bacterial ; Empyema/etiology ; Hemolytic-Uremic Syndrome/etiology ; Humans ; Meningitis/etiology ; Peritonitis/etiology ; Pneumococcal Infections/complications/*immunology ; Pneumonia, Pneumococcal/immunology ; Serotyping ; Streptococcus pneumoniae/*classification/pathogenicity

Little is known about the prevalence of naturally acquired IgG antibodies to the capsular polysaccharides of Streptococcus pneumoniae (pneumococcal IgG) in Korea. In the present study, we investigated transplacental transfer and age-related levels of pneumococcal IgG to provide background seroepidemiologic data for S. pneumoniae in Korea. One hundred thirty eight sera were assayed by ELISA for IgG to pneumococcal polysaccharide capsular serotypes 14 and 19, the predominant serotypes for under 15 yr of age in Korea. The subjects were divided into 7 subgroups according to age. The cord/maternal geometric mean titer of pneumococcal were 4.47+/-5.88/5.21 +/- 5.88 for serotype 14, and 4.68 +/- 5.55/6.55 +/- 6.92 for serotype 1 9 (mean +/- standard deviation, microg/mL). After birth, the geometric mean titers of pneumococcal IgG for serotypes 14 and 19 expressed in microg/mL were 1.18+/-2.12 and 1.41+/-2.17 in the 0-6 months group, 0.27+/-0.19 and 0.69+/-0.93 in 7-12 months, 0.21+/-0.22 and 0.64+/-1.32 in 1-2 yr, 0.69+/-0.78 and 2.65+/-2.46 in 3-6 yr, 2.52+/-2.72 and 8.29+/-4.24 in 7-10 yr, respectively. In conclusion, reduced transplacental transfer and very low serum concentrations of pneumococcal IgG may contribute to the susceptibility of neonates, infants, and young children to S. pneumoniae infection.
Age Factors ; Antibodies, Bacterial/metabolism* ; Bacterial Capsules/immunology* ; Child ; Child, Preschool ; Enzyme-Linked Immunosorbent Assay ; Female ; Human ; IgG/metabolism* ; IgG/blood ; Infant ; Infant, Newborn ; Male ; Maternal-Fetal Exchange* ; Pneumococcal Vaccines/immunology ; Pregnancy ; Streptococcus pneumoniae/immunology* ; Vaccines, Conjugate/immunology

OBJECTIVETo study on the preparation of Streptococcus pneumoniae psaA DNA vaccine and to analyse the immunogenicity by the prime-boost strategy.

METHODSThe psaA gene was amplified from the genome of Streptococcus pneumoniae by PCR, and then was inserted into plasmid pVAX1 and pET28a to construct recombinant expression vectors respectively. 293T cells were transiently transfected with pVAX1-psaA, and RT-PCR analysis of total cell RNA extracts showed successful expression of psaA. BALB/c mices (n = 5) were intramuscularly injected with 100 microg psaA DNA vaccine for three times, and then boosted with 50 microg recombinant PsaA protein. The antibody response against PsaA was measured by ELISA.

RESULTSThe psaA gene was amplified and subcloned successfully. The constructed psaA DNA vaccine was confirmed by DNA sequencing, and the recombinant PsaA protein was purified by the one-step Ni(2+) affinity chromatography. Expression of the PsaA was observed in cells transfected with pVAX1-psaA. The animal experiment results showed that the anti-PsaA level of the DNA prime-protein boosting mice was higher significantly than the other groups (t = 87.518, P < 0.05).

CONCLUSIONThe psaA DNA vaccine was prepared successfully, and the immunogenicity of Streptococcus pneumoniae psaA DNA vaccine could be improved significantly by the DNA prime and protein boost strategy.

Animals ; Antibody Formation ; genetics ; Female ; Genetic Vectors ; Immunization, Secondary ; Mice ; Mice, Inbred BALB C ; Nucleic Acid Amplification Techniques ; Plasmids ; Pneumococcal Infections ; immunology ; prevention & control ; Pneumococcal Vaccines ; immunology ; Streptococcus pneumoniae ; genetics ; immunology ; Vaccines, DNA ; immunology

Pneumococcal disease is a serious global public health problem and a leading cause of morbidity and mortality of children and adults in China. Antibiotics are commonly used to treat pneumococcal disease. However, antibiotic resistance to Streptococcus pneumoniae has become a severe problem around the world due to widespread antibiotic use. Immunoprophylaxis of pneumococcal disease with pneumococcal vaccines is therefore of great importance. In this article, we review the etiology, clinical presentation, epidemiology, and disease burden of pneumococcal disease and the vaccinology of pneumococcal vaccines. Our review is based on the Expert Consensus on Immunoprophylaxis of Pneumococcal Disease (2017 version), the Pneumococcal Vaccines WHO Position Paper (2019), and recent national and international scientific advances. This consensus article aims to provide public health and vaccination staff with appropriate evidence for pneumococcal vaccine use and to improve professional capacity for pneumococcal disease prevention and control.
Adult ; Child ; China/epidemiology* ; Consensus ; Humans ; Pneumococcal Infections/prevention & control* ; Pneumococcal Vaccines/therapeutic use* ; Streptococcus pneumoniae/immunology* ; Vaccines, Conjugate/administration & dosage*

Pneumococcal disease is one of the serious global public health problems, and an important leading cause of the morbidity and mortality of children and adults in China. Currently, antibiotics are the most choices for its clinical treatment. However, antibiotic resistance of Streptococcus pneumoniae has become a severe problem around the world due to the wide use of antibiotics. Hence, the prevention of pneumococcal disease by using pneumococcal vaccines is of great importance. In this article, we reviewed the etiology, clinic, epidemiology, disease burden of pneumococcal disease, and the vaccinology of pneumococcal vaccines, based on the Pneumococcal Vaccines WHO Position Paper (2012) and other latest evidence globally, to introduce comprehensive knowledge of pneumococcal disease, and for the purpose to improve the capacity of the professionals working on pneumococcal disease control and prevention and to provide appropriate evidences of pneumococcal vaccine applications for people who are engaged in public health and immunization vaccination.
Adult ; Child ; China/epidemiology* ; Consensus ; Humans ; Pneumococcal Infections/prevention & control* ; Pneumococcal Vaccines/administration & dosage* ; Public Health ; Streptococcus pneumoniae/immunology* ; Vaccination ; Vaccines, Conjugate/administration & dosage*

Although it is well known that pneumococcal conjugate vaccines provide cross-protection against some vaccine-related serotypes, these mechanisms are still unclear. This study was performed to investigate the role of cross-protective IgM antibodies against vaccine-related serotypes 6A, 6C, and 19A induced in children aged 12-23 months after immunization with 7-valent pneumococcal conjugate vaccine (PCV7). We obtained serum samples from 18 Korean children aged 12-23 months after a PCV7 booster immunization. The serum IgG and IgM concentrations of serotypes 6B and 19F were measured by enzyme-linked immunosorbent assay (ELISA) in serum. The opsonic indices (OIs) against vaccine serotypes 6B and 19F and vaccine-related serotypes 6A, 6C, and 19A were determined by an opsonophagocytic killing assay (OPA) in IgM-depleted and control serum. Both IgG and IgM antibodies in ELISA and opsonic indices in OPA against serotypes 6B and 19F were demonstrated in the immune serum. IgM depletion decreased the OIs against vaccine serotypes 6B (geometric means of OIs (GMIs) of 3,009 vs. 1,396, 38% reduction) and 19F (1,117 vs. 750, 36% reduction). In addition, IgM depletion markedly decreased the OIs against vaccine-related serotypes 6A (GMIs of 961 vs. 329, 70% reduction), 6C (432 vs. 185, 72% reduction), and 19A (301 vs. 166, 58% reduction). The booster immunization PCV7 induced protective antibodies in the form of both IgG and IgM isotypes. IgM antibodies contributed to eliciting cross-protection against vaccine-related serotypes as well as against vaccine serotypes.
Antibodies, Bacterial/blood ; Antibodies, Neutralizing/blood ; Enzyme-Linked Immunosorbent Assay ; Heptavalent Pneumococcal Conjugate Vaccine/*immunology ; Humans ; Immunoglobulin M/*blood ; Infant ; Pneumococcal Infections/*prevention & control ; Pneumococcal Vaccines/*immunology ; Serogroup ; Streptococcus pneumoniae/immunology