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Published on: August 19, 2016

The M protein of group A Streptococcus is a key virulence factor and a clinically relevant strain identification

David Metzgar1, Antonella Zampolli

  • 1Ibis Biosciences-Subsidiary of Abbott, Inc., Carlsbad, CA, USA. davidleemetzgar@yahoo.com

Virulence
|August 20, 2011
PubMed

Insights

Group A Streptococcus (GAS) M protein is key for virulence and immunity. Its variability aids in tracking GAS outbreaks and predicting disease outcomes, despite potential autoimmune links.

Area of Science:

  • Microbiology
  • Immunology
  • Epidemiology

Background:

  • The M protein is a major surface antigen of Group A Streptococcus (GAS), crucial for bacterial virulence and immune evasion.
  • It provides antiphagocytic properties essential for GAS survival in host tissues.
  • Specific M protein regions can elicit autoimmune responses, potentially leading to conditions like rheumatic heart disease.

Purpose of the Study:

  • To highlight the critical role of M protein in GAS pathogenesis and host immunity.
  • To emphasize the significance of M protein as a target for epidemiological typing and outbreak surveillance.
  • To discuss the implications of M protein's antigenic properties in autoimmune sequelae.

Main Methods:

  • Review of existing literature on M protein structure, function, and antigenicity.
  • Analysis of M protein's role in GAS virulence and immune response.
  • Evaluation of M protein typing as an epidemiological tool.

Main Results:

  • M protein is essential for GAS survival and virulence through antiphagocytic mechanisms.
  • M protein variability is central to type-specific immunity and epidemiological classification.
  • Cross-reactivity with human proteins suggests a mechanism for autoimmune disease development.

Conclusions:

  • M protein is a critical determinant of GAS virulence, immunity, and epidemiology.
  • M protein typing remains a valuable tool for tracking GAS outbreaks and assessing public health threats.
  • Understanding M protein's antigenic properties is vital for both infectious disease control and autoimmune disease research.

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