Intelectin-2 is a broad-spectrum antimicrobial lectin

Area of Science:

• Microbiology
• Immunology
• Biochemistry

Background:

• Mammals maintain native microbiota at colonization sites.
• Lectins at mucosal barriers influence microbial populations, but their roles are often unclear.
• Intelectins are found in chordates, but their functions remain poorly characterized.

Purpose of the Study:

• To investigate the functional roles of mammalian intelectin-2 (mItln2 and hItln2) at mucosal barriers.
• To determine the mechanisms by which intelectins interact with mammalian and microbial components.
• To elucidate the antimicrobial and defensive functions of intelectin-2 in mucosal immunity.

Main Methods:

• Carbohydrate recognition assays to assess binding to mucins and microbial glycans.
• Microbial interaction studies with native microbial communities and isolates.
• Viability assays to determine the impact of intelectin binding on microbial cells.
• Calcium-dependency studies for glycan binding.

Main Results:

• Mouse intelectin-2 (mItln2) and human intelectin-2 (hItln2) engage and crosslink mucins through carbohydrate recognition.
• Both lectins recognize and bind to various microbes, including gram-positive and gram-negative bacteria.
• Intelectin binding to microbes leads to a loss of viability, while human cells remain unaffected.
• Glycan binding is calcium-coordinated, enabling interaction with both host and microbial carbohydrate residues.

Conclusions:

• Mammalian intelectin-2 plays a critical antimicrobial role in mucosal defense.
• Intelectin-2 functions both offensively (microbial killing) and defensively (mucus crosslinking).
• These dual roles are essential for regulating microbial colonization at mucosal surfaces.