sre-33 Antibody

Overview of IL-33 and Its Receptor System

Interleukin-33 (IL-33) is a dual-function alarmin cytokine in the IL-1 family, critical for tissue homeostasis and immune regulation . Its receptor, ST2 (IL-33R), forms a heterodimer with IL-1RAcP to activate signaling cascades in Th2 cells, ILC2s, and other immune cells . Dysregulation of the IL-33/ST2 axis is implicated in inflammatory diseases, infections, and autoimmune conditions .

Tozorakimab (MEDI3506)

• Mechanism: Dual inhibition of IL-33 signaling via ST2 and RAGE/EGFR pathways .

• Affinity: Femtomolar binding (K_D = 30 fM for IL-33^red), surpassing soluble ST2 (sST2) .

• Efficacy:

  • Inhibits IL-33-induced NF-κB signaling and cytokine release in primary human cells .

  • Reduces lung injury in murine models by neutralizing rapid IL-33 release .

Anti-IL-33 Antibody [EPR17831] (ab229698)

• Applications: Western blot (WB), IHC-P, flow cytometry .

• Specificity: Detects 15–30 kDa bands in mouse tissues (spleen, lymph nodes) .

• Validation: Knockout controls confirm specificity for IL-33 in murine models .

BD Pharmingen™ PE Anti-Human ST2 (U33-374)

• Target: IL-33 Receptor (ST2) on Th2 cells, eosinophils, and mast cells .

• Function: Blocks IL-33 binding, serving as a decoy receptor in soluble form .

Autoimmune Disease Associations

• Rheumatoid Arthritis (RA): Serum IL-33 correlates with auto-antibody positivity (RF/anti-CCP) but not treatment response :

• Systemic Lupus Erythematosus (SLE): Anti-RA33 antibodies associate with high disease activity and mucocutaneous involvement (AUC = 0.634, specificity = 92.9%) .

Therapeutic Implications

• Respiratory Diseases: IL-33 drives ILC2-mediated eosinophilia and airway hyper-responsiveness in murine models . Neutralizing antibodies reduce epithelial injury and inflammation .

• Bacterial Infections: IL-33 enhances neutrophil extracellular trap production against S. aureus and improves macrophage bactericidal activity .

Technical Comparisons of IL-33 Antibodies

Challenges and Future Directions

• Dual Signaling: IL-33 oxidation state (IL-33^red vs. IL-33^ox) requires antibodies like tozorakimab to block both ST2 and RAGE/EGFR pathways .

• Biomarker Potential: Serum IL-33 detection lacks prognostic value for biologic therapies in RA but may guide personalized approaches in SLE .