Discovery, Function, and Therapeutic Targeting of Siglec-8

Area of Science:

• Immunology
• Cell Biology
• Allergy and Inflammation Research

Background:

• Sialic acid-binding immunoglobulin-like lectins (Siglecs) are cell surface receptors with inhibitory immune functions.
• Siglec-8 is selectively expressed on human mast cells and eosinophils, key players in allergic and inflammatory diseases.
• Engagement of Siglec-8 inhibits mast cell degranulation and induces eosinophil cell death.

Purpose of the Study:

• To review the discovery and functions of Siglec-8.
• To explore therapeutic strategies targeting Siglec-8 for immune-mediated diseases.
• To discuss the clinical development of anti-Siglec-8 antibodies.

Main Methods:

• Review of in vitro studies on Siglec-8 engagement with antibodies and ligands.
• Analysis of in vivo studies using humanized and transgenic mouse models.
• Examination of clinical trial data for AK002 (lirentelimab).

Main Results:

• In vitro and in vivo studies demonstrate Siglec-8 engagement induces eosinophil apoptosis and inhibits mast cell degranulation.
• Anti-Siglec-8 antibody administration shows anti-inflammatory effects.
• AK002 (lirentelimab) has demonstrated safety and efficacy in inhibiting mast cell activity and depleting eosinophils in clinical trials.

Conclusions:

• Siglec-8 is a promising therapeutic target for mast cell- and eosinophil-mediated diseases.
• Targeting Siglec-8 offers a novel strategy for treating allergic and inflammatory conditions.
• Further clinical development of anti-Siglec-8 therapies is warranted.