Streptococcus Pyogenes Antibodies, Proteins & ELISA Kits

Streptococcus pyogenes or group A Streptococcus (GAS) is a well known human-specific bacterial pathogen that is responsible for a wide range of human diseases. These diseases range from mild infections such as pharyngitis, to life-threatening invasive infections including streptococcal toxic shock syndrome.

S. pyogenes causes three different types of disease; tissue invasion (pyogenic) diseases are caused by streptococcus directly invading the tissue and causing damage, toxigenic diseases are caused by the exotoxin coming from the bacteria, and immunogenic diseases which are caused by the host immune response. S. pyogenes has enzymes and toxins that contribute to its virulence, namely, streptolysin O enzyme and erythrogenic exotoxin A. The M protein of this bacterium mediates its adherence to keratinocytes. In addition, this protein functions in immune evasion, especially in phagocytosis and the complement system.

The hyaluronic-acid-binding protein CD44 functions in the specific recognition of the hyaluronic acid capsular polysaccharide of S. pyogenes. Subsequently, S. pyogenes attaches to human skin epithelial or pharyngeal cells.  

CD46, or membrane cofactor protein (MCP), is a transmembrane glycoprotein located on the surface of keratinocytes. The M protein directly binds to MCP. However, mutant M proteins lacking the C repeat domain did not bind MCP. This suggests that recognition of MCP is vital for streptococcus to adhere to keratinocytes.

Fibronectin is a high-molecular weight glycoprotein that exists as a fibrillar polymer in the ECM and as a soluble protein in plasma. This adhesive glycoprotein is a primary target of streptococcal adhesion which connects bacterial adhesion molecules to integrin receptors on the cell surface. S. pyogenes strains express ~11 fibronectin-binding adhesins.

The cellular receptors primarily responsible for fibronectin binding protein-mediated internalisation of S. pyogenes are integrins. Integrins are transmembrane receptors that facilitate binding to the ECM. Integrins are capable of fibronectin binding.

Extracellular enzymes from S. pyogenes are vital for its pathogenesis. SpeB or streptococcal pyrogenic exotoxin B, is one of the most studied enzymes. SpeB acts as a proteolytic factor that cleaves E-cadherin. This occurs within the extracellular domain, in the region neighbouring calcium-binding sites. Increased levels of active SpeB result in increased cleavage of E-cadherin.

Angiostatin is a human Pg-derived angiogenesis inhibitor. As demonstrated through X-ray crystallography, angiostatin complexes to VEK-30, a peptide from the S. pyogenes surface protein. Thus, providing a model of the interaction between streptococcal-derived pathogenic proteins and Pg.

Epithelial Cell Adhesion Molecule (EPCAM) is a transmembrane glycoprotein which promotes transcription factor-mediated pluripotency reprogramming. A significant increase in EPCAM was noted in endothelial cells upon infection with S. pyogenes.

The PDGF protein is composed of two subunits, an A and a B chain. The PDGF-AB isoform functions as a chemotactic agent for inflammatory cells. PDGF-AB levels were elevated significantly in the presence of S. pyogenes.

S. pyogenes is recognized by TLRs which signal through MyD88, triggering a signaling cascade. As a result, the expression of cytokines IFN-Beta, TNF, IL-12 and IL-6 are activated. In addition, TLRs also signal through TIR domain-containing adaptor protein (TIRAP) and TIR-domain-containing adapter-inducing interferon-B (TRIF). TLR9 stimulates nitric oxide (NO) production, thus killing S. pyogenes. TLR13 recognizes S. pyogenes rRNA and as a result, functions in the activation of innate immune responses.

Dendritic cells (DCs) are a primary source of S. pyogenes-elicited IL-12 which stimulates NK cells to generate IFN-Gamma. Many other cytokines and chemokines are produced by DCs upon exposure to S. pyogenes. These include IL-1B and CXCL1. IL-1B is induced by S. pyogenes in an NLRP3-dependent manner.

Recent studies have identified a significant contribution of IL-17-producing Th17 cells to the clearance of S. pyogenes in a mouse model of pharyngitis. It is assumed that the presence of neutrophils in infected tissues is significantly enhanced by IL-17-mediated neutrophil expansion. In addition, mice deficient in the CCL2 chemokine receptor CCR2 displayed a moderate increase in susceptibility to S. pyogenes.

• Measure up to 24 analytes by Flow Cytometry
• Only 15μL of sample required
• Pre-mixed panels for Human, Mouse, Rat & Non-Human Primate
• Create your own custom panel

Immunometabolism plays a key role in human health and disease. It describes the series of changes that occur within the intracellular metabolic pathways of immune cells during activation.

Streptococcaceae, including S. pyogenes, use glycolysis for energy production. Lactic acid is the metabolic end product. For S. pyogenes, catabolism of arginine via the arginine deiminase (ADI) pathway provides protection against acid stress and supplements energy production. Arginine expression is enhanced in mouse models of S. pyogenes infection, suggesting an important role in vivo. In S. pyogenes, fatty acid biosynthesis machinery is highly conserved, it involves the FASII-containing multi-enzyme complex.

Assay Genie provides Glycolysis, Arginase and Fatty Acid Oxidation immunometabolism assay kits that would support Streptococcus Pyogenes research.

The best studied and most widely used animal model for S. pyogenes research is the murine subcutaneous ulcer model. The success of this model is attributed to its ability to reproduce core features of S. pyogenes diseases. A variant of this model has been developed using rats with the intention to expand the number of streptococcal strains available for investigation. There is great demand to develop non-human primate models of S. pyogenes-related diseases. When compared with rodent models, NHPs present with more similar development and immune responses to humans.

Assay Genie offers a wide range of animal model ELISA kits with the potential to support the advancing field of Streptococcus Pyogenes research.