<i>emm</i> Typing of Group A Streptococcus Clinical Isolates: Identification of Dominant Types for Throat and Skin Isolates

Tanaka, Daisuke; Gyobu, Yotaku; Kodama, Hirohide; Isobe, Junko; Hosorogi, Shiho; Hiramoto, Yuko; Karasawa, Tadahiro; Nakamura, Shinichi

doi:10.1111/j.1348-0421.2002.tb02715.x

Cited by 29 publications

(22 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The number of distinct emm/st types, 78, detected among the present collection of GAS strains is much higher than has been found in several emm typing reports from other countries, where larger numbers of isolates collected over a longer period of time were screened (5,12,16,31,35,39). In Japan only 29 emm/st types were detected among 906 clinical isolates collected from 1990 to 1999 (35).…”

Section: Discussionmentioning

confidence: 41%

See 1 more Smart Citation

M Protein Gene ( emm Type) Analysis of Group A Beta-Hemolytic Streptococci from Ethiopia Reveals Unique Patterns

Tewodros

Kronvall

2005

J Clin Microbiol

View full text Add to dashboard Cite

The genetic diversity of group A streptococcal (GAS) isolates obtained in 1990 from Ethiopian children with various streptococcal diseases was studied by using emm gene sequence analysis. A total of 217 GAS isolates were included: 155 and 62 isolates from throat and skin, respectively. A total of 78 different emm/st types were detected among the 217 isolates. Of these, 166 (76.5%) belonged to 52 validated reference emm types, 26 (11.9%) belonged to 16 already recognized sequence types (st types) and 25 (11.5%) belonged to 10 undocumented new sequence types. Resistance to tetracycline (148 of 217) was not correlated to emm type. Isolation rate of the classical rheumatogenic and nephritogenic strains was low from cases of acute rheumatic fever (ARF) and acute glomerulonephritis (AGN), respectively. Instead, the recently discovered st types were overrepresented among isolates from patients with ARF (3 of 7) and AGN (9 of 16) (P < 0.01) compared to isolates from subjects with tonsillitis and from healthy carriers (10 of 57 and 16 of 90, respectively). In contrast to rheumatogenic strains from the temperate regions, more than half of the isolates from ARF (four of seven) carried the genetic marker for skin preference, emm pattern D, although most of them (six of seven) were isolated from throat. Of 57 tonsillitis-associated isolates, 16 (28%) belonged to emm pattern D compared to <1% in temperate regions. As in other reports emm patterns A to C were strongly associated with throat, whereas emm pattern D did not correlate to skin. This first large-scale emm typing report from Africa has demonstrated a heterogeneous GAS population and contrasting nature of GAS epidemiology in the region.Accurate identification and typing of group A hemolytic streptococci (GAS) is an essential part of epidemiological and pathogenetic studies of streptococcal diseases. A serotyping system based on antigenic variation of a surface exposed M protein and developed by Rebecca Lancefield has been in use since 1928. Although additional serotyping systems, the T and OF typing, were developed as valuable and practical substitutes, the M typing system was considered the gold standard. However, a limited supply of antisera and the high nontypeability rate among isolates, in particular those from the tropics, challenged its continued usage. In recent years, several molecular typing systems have been reported as alternatives for M typing (4,19,25). Most of the knowledge that has been accumulated concerning GAS epidemiology is based on M typing system; hence, a molecular system that correlates with this system has practical significance. The emm typing system (4, 25) which is based on sequence analysis of PCR products of the N-terminal hypervariable region of the M protein gene, concurs with M serotyping almost 1:1 (17). In addition to its simplicity, this typing system has allowed the detection of several previously unknown GAS types from different geographic regions (5,24,32,36).

show abstract

Section: Discussionmentioning

confidence: 41%

“…In Japan only 29 emm/st types were detected among 906 clinical isolates collected from 1990 to 1999 (35). In Mexico, only 31 emm types were detected among 423 isolates collected from symptomatic pharyngeal specimens from 1991 to 2000 (16).…”

Section: Discussionmentioning

confidence: 99%

M Protein Gene ( emm Type) Analysis of Group A Beta-Hemolytic Streptococci from Ethiopia Reveals Unique Patterns

Tewodros

Kronvall

2005

J Clin Microbiol

View full text Add to dashboard Cite

show abstract

“…The 5Ј ends of emm genes are highly heterogeneous and encode the serotype specificity used for the M typing system developed by Lancefield in 1928. Since, in 1995, Beall et al demonstrated the usefulness of emm gene sequence analysis for the routine typing of GAS (5), few studies have used this typing method for monitoring S. pyogenes diversity (4,5,8,9,27).…”

mentioning

confidence: 99%

Survey of emm Gene Sequences from Pharyngeal Streptococcus pyogenes Isolates Collected in Spain and Their Relationship with Erythromycin Susceptibility

et al. 2003

View full text Add to dashboard Cite

We conducted a nationwide survey of the variable 5 emm (M protein gene) sequences from 614 pharyngeal Streptococcus pyogenes isolates susceptible (299 isolates) and resistant (315 isolates) to erythromycin that were isolated in Spain from 1996 to 1999. Almost 98% of these isolates had emm sequences in agreement with previously recorded M antigen association. We only identified a new 5 emm sequence in 17 isolates. Nine different emm types accounted for 85% of the S. pyogenes isolates susceptible to erythromycin. By contrast, only 3 emm types accounted for 70% of the erythromycin-resistant isolates. Further characterization of these isolates by ribotyping and pulsed-field gel electrophoresis indicated that high frequency of erythromycin resistance in Spain is due to few clones.

show abstract

“…We observed that M42 and M48 were not only different from previously reported M types in India, but also from the other Asian countries such as Japan, Taiwan, and Hong Kong, where M28 and M12 were reported to predominate [37][38][39]. In contrast to these countries, the most common serotype in Australia was M14, in Italy M12, in Spain M4, and in Germany and the United States, M1 prevailed, followed by M12 [2,12,20,[40][41][42].…”

Section: Discussionmentioning

confidence: 49%

Molecular epidemiology and virulence characteristics of prevalent group A streptococci recovered from patients in northern India

Arya

Sharma

Mehta

et al. 2014

J Infect Dev Ctries

View full text Add to dashboard Cite

Introduction: In this study, the prevalence of M types of Group A Streptococcus (GAS) in North India, invasive behavior of prevalent M types, and inflammatory immune response by host cells were studied. Methodology: A total of 1,047 clinical samples were collected between 2004 and 2010. Confirmation of GAS was determined by serotyping and M types were identified by emm gene sequencing. The most prevalent serotypes were selected to study their invasive behavior and inflammatory immune response under different temperatures and salt concentrations in A549 and HEp-2 cells. Results: Ninety-two isolates were identified as GAS of which 17 were M types with 18.5% heterogeneity. The most prevalent M types were M1 (21.73%) and M49 (8.7%), respectively. M1 and M49 were used to study virulence potential and inflammatory immune responses. The efficiency of cell infection decreased with increased temperature for both M types, increasing with lowering temperatures compared to the uninfected control (37°C). As salt concentration was increased, cell infection efficiency was lowered with some exceptions; the infection efficiency of M1 strain in A549 cells with 0.6 M NaCl was 50 fold higher (p ≤ 0.03). Significantly increased production of IL-6 and IL-8 was observed in both cell lines infected with GAS and when grown under different environmental conditions compared to uninfected cell lines. Conclusions: This study determined the prevalence of different M types in North India and showed that environmental conditions can regulate cell infection by GAS . This information may influence the selection of GAS serotypes used in vaccine development.

show abstract

emm Typing of Group A Streptococcus Clinical Isolates: Identification of Dominant Types for Throat and Skin Isolates

Cited by 29 publications

References 21 publications

M Protein Gene ( emm Type) Analysis of Group A Beta-Hemolytic Streptococci from Ethiopia Reveals Unique Patterns

M Protein Gene ( emm Type) Analysis of Group A Beta-Hemolytic Streptococci from Ethiopia Reveals Unique Patterns

Survey of emm Gene Sequences from Pharyngeal Streptococcus pyogenes Isolates Collected in Spain and Their Relationship with Erythromycin Susceptibility

Molecular epidemiology and virulence characteristics of prevalent group A streptococci recovered from patients in northern India

Contact Info

Product

Resources

About