• Journal of Yeungnam Medical Science
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• v.29 no.1
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• pp.1-8
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• 2012

Streptococcus pneumonia is a very important pathogen for children and elderly people. Two types of pneumococcal vaccines are available in the market: pneumococcal polysaccharide vaccine (PPSV) and pneumococcal conjugate vaccine (PCV). PPSVs have been used for more than 30 years, and PCVs for about 10 years. There have been many reports concerning the evaluation of the vaccines' efficacies in preventing pneumococcal diseases such as meningitis, pneumonia, and otitis media and bacteremia, but the clinical trials had been performed with different conditions, such as diverse vaccine valencies, age groups, races, target outcomes, immunological cut-off values, and follow-up periods. PPSV is recommended for elderly people and chronic disease patients such as asthma, diabetes mellitus, chronic renal failure, and hyposplenic patients. According to the data from several systemic reviews and population-based surveillances, PPSV is effective for pneumococcal pneumonia and vaccine-type bacteremia among healthy adults. Until now, however, there is insufficient evidence of the effectiveness of PPSV among high-risk adults. PCV is very effective in preventing vaccine-type invasive pneumococcal disease (IPD) among children, but its efficacy for pneumonia is very low among children. The incidence of vaccine-related or non-vaccine-type IPDs is increasing after the introduction of 7-valent PCV (PCV7) as a routine immunization for children. Recently, 10- and 13-valent PCVs have been used for children, instead of PCV7. Therefore, continuous surveillance for serotype change among pneumococcal diseases is necessary to evaluate the vaccines' efficacy.

• Journal of Korean Medical Science
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• v.33 no.51
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• pp.340.1-340.14
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• 2018

Background: Various pneumococcal vaccines have been evaluated for immunogenicity by opsonophagocytic assay (OPA). A multiplexed OPA (MOPA) for 13 pneumococcal serotypes was developed by Nahm and Burton, and expanded to 26 serotypes in 2012. The development of new conjugate vaccines with increased valence has necessitated expanded MOPAs to include these additional serotypes. In this study, we validated this expanded MOPA platform and applied to measure antibodies against 11 additional serotypes (2, 8, 9N, 10A, 11A, 12F, 15B, 17F, 20B, 22F, and 33F) in human sera. Methods: All materials, including serum, complement, bacterial master stocks, and HL-60 cells, were evaluated for assay optimization. Following optimization, the assay was validated for accuracy, specificity, and intra- and inter-assay precision with sera from adult donors following standard protocols. The assay was applied to evaluate functional antibodies of 42 sera immunized with 23-valent pneumococcal polysaccharide vaccine (PPV23). Results: The expanded MOPA platform was specific for all serotypes, with the exception of serotype 20. The assay results were highly correlated with those obtained from single-serotype OPA, indicating acceptable accuracy. The coefficients of variation were 7%-24% and 13%-39% in tests of intra- and inter-assay precision, respectively, using three quality-control samples. A MOPA that included 11 additional serotypes in the PPV23 was established and validated with respect to accuracy, specificity, and precision. The opsonic indices of immune sera were obtained using this validated assay. Conclusion: The expanded MOPA will be useful for evaluation of the immunogenicity of PPV23 and future conjugate vaccine formulations.

• Clinical and Experimental Pediatrics
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• v.48 no.5
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• pp.506-511
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• 2005

Purpose : Streptococcus pneumoniae serotype 6B and 6A are important pathogens in pneumococcal infections. It is commonly assumed that the 6B vaccines elicit antibodies cross-reacting with the 6A serotype and the cross-reactive antibodies protect against infections of 6A. To examine this assumption, we measured the opsonophagocytic capacity to serotype 6A and 6B in adults. Methods : Twenty-four adults were immunized with pneumococcal PS vaccine that contains 6B PS. Their preimmune and postimmune sera were studied for the capacity to opsonize 6B and 6A serotypes with opsonophagocytic killing assay. Results : Opsonization titers to 6B were significantly higher than those to 6A in preimmune and postimmune sera. Because significant increasesof opsonization titers were observed in adults with polysaccharide vaccines for 6A(cross-reactive) serotype as well as for 6B(vaccine) serotype, 6B PS in vaccine elicited cross-protective antibodies to 6A, but not in all cases. One adult did not have detectable levels of opsonization titers to 6A after immunization. Conclusion : Although 6B PS in pneumococcal PS vaccine elicits antibodies cross-reacting with 6A serotype in some adults, it may not occur always. This study should be extended to other age groups such as children and elderly people. The presence of the cross-protection should be directly determined in clinical trials of the pneumococcal vaccines as well as during the postlicensure monitoring surveys by serotyping the clinical isolates of pneumococci.

• Pediatric Infection and Vaccine
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• v.15 no.1
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• pp.1-4
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• 2008

Immunizations are among the most cost-effective and widely used public health interventions. This is a report a revision of recommendation of immunization for children by Korean Pediatric Society. Immunization. Vaccines were divided into 4 groups. 1) Vaccines that are recommended to all infants and children (BCG, hepatitis B vaccine, DTaP, Td, Polio vaccine, Japanese encephalitis vaccine, MMR, varicella vaccine, influenza vaccine [6-23 months of age], H. influenzae type b vaccine), 2) those that can be administered to all infants and children, but decision of administration is made by parents (pneumococcal conjugate vaccine, hepatitis A vaccine, influenza vaccine [healthy children ${\geq}24$ months of age], rotavirus vaccine, human papilloma virus vaccine), 3) those that should be given to high risk group (pneumococcal polysaccharide vaccine [high risk patients ${\geq}24$ months of age], influenza vaccine [high risk patients ${\geq}24$ months of age], typhoid vaccine), and 4) those administered for control of outbreaks or prevention of emerging infectious diseases. Immunization schedule recommended by Korean Pediatric Society in 2008 is presented.

• Clinical and Experimental Pediatrics
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• v.56 no.7
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• pp.286-290
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• 2013

Purpose: Although chronic and recurrent rhinosinusitis is prevalent in children, little is known about its causes. Here, we investigated the humoral immunity in children with chronic or recurrent rhinosinusitis. Methods: We examined 16 children attending the outpatient clinic at the CHA Bundang Medical Center including 11 boys and 5 girls, aged 3-11 years (mean age, 5.6 years), who had rhinosinusitis for >3 months or >3 times per year. The complete blood count with differential and total serum concentrations of Immunoglobulin (Ig) E, IgA, IgD, IgM, IgG, and IgG subclasses ($IgG_1$, $IgG_2$, $IgG_3$, and $IgG_4$) of all children were measured. All subjects received 23-polysaccharide pneumococcal vaccination (PPV), and the levels of antibodies to 5 serologic types (4, 6B, 14, 18C, and 23F) of pneumococcal capsular polysaccharide antigens were measured before and after vaccination. Post-PPV antibody titers ${\geq}0.35{\mu}g/mL$ or with a ${\geq}4$-fold increase were considered as positive responses. Results: The titers of IgG, IgA, IgD, and IgM were within normal range in all 16 children, whereas the total IgE concentration was higher than normal in 2 children. $IgG_1$ deficiency was observed in 1 patient and $IgG_3$ deficiency in 3. After PPV, 1 patient failed to respond to all 5 serologic types, 2 failed to respond to 4 serologic types, and 2 failed to respond to 3 serologic types. Conclusion: Clinicians should consider the evaluation of humoral immune functions in children with chronic or recurrent rhinosinusitis who do not respond to prolonged antibiotic treatment.

• Pediatric Infection and Vaccine
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• v.22 no.2
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• pp.97-105
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• 2015

Purpose: Serotyping pneumococcal isolates is important to monitor efficacy of pneumococcal vaccines. Because of difficulties of typing pnueumocci, a multiplex bead-based (multibead) serotyping assay was recently introduced. The aim of this study is to establish a new multibead serotyping assay and to apply this method to analyze clinical isolates of pneumococci in Korea. Methods: To establish the multibead serotyping assay, six key reagents were transferred from University of Alabama at Birmingham (UAB) to Ewha Center for Vaccine Evaluation and Study (ECVES): bead set coated with polysaccharide and monoclonal antibody pool were used in one multiplex inhibition-type immunoassay and 2 bead sets coated DNA probe and 2 primer pools were used in two multiplex PCR-based assays. After multibead serotyping assay was set up, 75 test samples of pneumococci were analyzed whether ECVES is able to identify serotype correctly. After confirming the performance, serotyping assay was applied to identify serotypes of 528 clinical isolates of pneumococci collected from 3 different hospitals. Results: After establishment of the multibead pneumococcal serotyping assay system at ECVES, 75 test samples were analyzed. There was no discrepancy of serotypes of 75 test samples between the results assigned at UAB and those at ECVES. The serotypes of 528 pneumococci isolated from patients or healthy subjects were determined in 94.3% of isolates (498/528). Conclusions: The multibead pneumococcal serotyping assay can be successfully established in Korea. With this method, surveillance of serotypes of pneumococci isolated from patients as well as healthy subjects could be studied.