Current methods for capsular typing of Streptococcus pneumoniae

Jauneikaite, Elita; Tocheva, Anna S.; Jefferies, Johanna M.C.; Gladstone, Rebecca A.; Faust, Saul N; Christodoulides, Myron; Hibberd, Martin L.; Clarke, Stuart C.

doi:10.1016/j.mimet.2015.03.006

Cited by 75 publications

(71 citation statements)

References 94 publications

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“…However, with the developments of vaccination and the resulting serotype shift, serotyping of pneumococci has returned to the forefront of clinical interest. As long as pneumococcal vaccines are based on PS capsules, there will be a need for methods to determine capsular types (202)(203)(204)(205). A serotyping system should ideally detect all the known pneumococcal serotypes and then distinguish each serotype; however, in view of potentially vast capsular diversity, one needs to consider how much resolution a serotyping system needs and adjust analytical demands accordingly.…”

Section: Analytical Approaches To Serotyping Pneumococcimentioning

confidence: 99%

Pneumococcal Capsules and Their Types: Past, Present, and Future

et al. 2015

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SUMMARY Streptococcus pneumoniae (the pneumococcus) is an important human pathogen. Its virulence is largely due to its polysaccharide capsule, which shields it from the host immune system, and because of this, the capsule has been extensively studied. Studies of the capsule led to the identification of DNA as the genetic material, identification of many different capsular serotypes, and identification of the serotype-specific nature of protection by adaptive immunity. Recent studies have led to the determination of capsular polysaccharide structures for many serotypes using advanced analytical technologies, complete elucidation of genetic basis for the capsular types, and the development of highly effective pneumococcal conjugate vaccines. Conjugate vaccine use has altered the serotype distribution by either serotype replacement or switching, and this has increased the need to serotype pneumococci. Due to great advances in molecular technologies and our understanding of the pneumococcal genome, molecular approaches have become powerful tools to predict pneumococcal serotypes. In addition, more-precise and -efficient serotyping methods that directly detect polysaccharide structures are emerging. These improvements in our capabilities will greatly enhance future investigations of pneumococcal epidemiology and diseases and the biology of colonization and innate immunity to pneumococcal capsules.

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Section: Analytical Approaches To Serotyping Pneumococcimentioning

confidence: 99%

Pneumococcal Capsules and Their Types: Past, Present, and Future

et al. 2015

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“…Furthermore, this method of typing requires the recovery of a viable pneumococcal culture and thus precludes cases where an isolate is not obtained-for example, when antimicrobial treatment has been administered prior to specimen collection (13,14), or in cases of noninvasive disease. The development of pneumococcal capsular typing methods using a number of techniques, such as specific enzyme-linked immunosorbent assay (ELISA), competitive enzyme immunoassay (EIA), multiplex immunoassay (MIA), single and multiplex PCRs, and capsular sequence typing (CST) (15)(16)(17)(18)(19)(20)(21), has contributed to serogroup/serotype surveillance of invasive and noninvasive PD, particularly when an isolate is unavailable, by their direct application to clinical specimens.…”

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confidence: 99%

Development of an Extended-Specificity Multiplex Immunoassay for Detection of Streptococcus pneumoniae Serotype-Specific Antigen in Urine by Use of Human Monoclonal Antibodies

Eletu

Sheppard

Thomas

et al. 2017

Clin Vaccine Immunol

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Current pneumococcal vaccines cover the 10 to 23 most common serotypes of the 92 presently described. However, with the increased usage of pneumococcal-serotype-based vaccines, the risk of serotype replacement and an increase in disease caused by nonvaccine serotypes remains. Serotype surveillance of pneumococcal infections relies heavily on culture techniques, which are known to be insensitive, particularly in cases of noninvasive disease. Pneumococcal-serotypespecific urine assays offer an alternative method of serotyping for both invasive and noninvasive disease. However, the assays described previously cover mainly conjugate vaccine serotypes, give little information about circulating nonvaccine serotypes, and are currently available only in one or two specialist laboratories. Our laboratory has developed a Luminex-based extended-range antigen capture assay to detect pneumococcal-serotype-specific antigens in urine samples. The assay targets 24 distinct serotypes/serogroups plus the cell wall polysaccharide (CWP) and some cross-reactive serotypes. We report that the assay is capable of detecting all the targeted serotypes and the CWP at 0.1 ng/ml, while some serotypes are detected at concentrations as low as 0.3 pg/ml. The analytical serotype specificity was determined to be 98.4% using a panel of polysaccharide-negative urine specimens spiked with nonpneumococcal bacterial antigens. We also report clinical sensitivities of 96.2% and specificities of 89.9% established using a panel of urine specimens from patients diagnosed with community-acquired pneumonia or pneumococcal disease. This assay can be extended for testing other clinical samples and has the potential to greatly improve serotype-specific surveillance in the many cases of pneumococcal disease in which a culture is never obtained.KEYWORDS diagnostics, immunization, monoclonal antibodies, pneumococcus, surveillance studies D espite being vaccine preventable, Streptococcus pneumoniae (pneumococcus) remains a major cause of morbidity and mortality worldwide. Pneumococcal disease (PD) includes both invasive and noninvasive disease. The former includes bacteremia and meningitis; the latter, nonbacteremic pneumonia, sinusitis, and acute otitis media. To date, 97 "serotypes" of pneumococcus have been reported (1); however, some of these show only genotypic differences and produce the same polysaccharide structures (2). Ninety-two serotypes are currently described by the Danish system using commercial typing sera from SSI Diagnostica AG (Hillerød, Denmark). These serotypes differ in

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“…The tedious determination of bacterial serotypes is being overcome by the recent advancement of typing methods [145,146]. Especially for pneumococci, encapsulated by more than 90 PS varieties, fast and specific sero- as well as resistance typing is critical to deciding on the treatment of the infection.…”

Section: Bacterial Genomics and Proteomics (Sero- And Resistance-tmentioning

confidence: 99%

From Immunologically Archaic to Neoteric Glycovaccines

Cavallari

Libero

2017

Vaccines

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Polysaccharides (PS) are present in the outermost surface of bacteria and readily come in contact with immune cells. They interact with specific antibodies, which in turn confer protection from infections. Vaccines with PS from pneumococci, meningococci, Haemophilus influenzae type b, and Salmonella typhi may be protective, although with the important constraint of failing to generate permanent immunological memory. This limitation has in part been circumvented by conjugating glycovaccines to proteins that stimulate T helper cells and facilitate the establishment of immunological memory. Currently, protection evoked by conjugated PS vaccines lasts for a few years. The same approach failed with PS from staphylococci, Streptococcus agalactiae, and Klebsiella. All those germs cause severe infections in humans and often develop resistance to antibiotic therapy. Thereby, prevention is of increasing importance to better control outbreaks. As only 23 of more than 90 pneumococcal serotypes and 4 of 13 clinically relevant Neisseria meningitidis serogroups are covered by available vaccines there is still tremendous clinical need for PS vaccines. This review focuses on glycovaccines and the immunological mechanisms for their success or failure. We discuss recent advances that may facilitate generation of high affinity anti-PS antibodies and confer specific immunity and long-lasting protection.

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Current methods for capsular typing of Streptococcus pneumoniae

Cited by 75 publications

References 94 publications

Pneumococcal Capsules and Their Types: Past, Present, and Future

Pneumococcal Capsules and Their Types: Past, Present, and Future

Development of an Extended-Specificity Multiplex Immunoassay for Detection of Streptococcus pneumoniae Serotype-Specific Antigen in Urine by Use of Human Monoclonal Antibodies

From Immunologically Archaic to Neoteric Glycovaccines

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