Variations in lectin binding properties of intestinal M cells

Area of Science:

• Immunology
• Glycobiology
• Gastroenterology

Background:

• Follicle-associated epithelia (FAE) contain specialized M cells crucial for immune surveillance.
• Understanding M cell surface characteristics is vital for antigen uptake and targeted drug delivery.
• Glycoconjugate expression on M cells varies significantly between species and anatomical locations.

Purpose of the Study:

• To investigate and compare glycoconjugate expression on M cells in murine and rabbit Peyer's patches and caecal patches.
• To identify specific lectin binding patterns indicative of M cell surface glycoconjugates.
• To assess the implications of observed variations for M cell function and targeted delivery.

Main Methods:

• Application of a panel of lectins to fixed, whole tissue preparations of mouse and rabbit Peyer's and caecal patches.
• Selective binding of alpha-L-fucose-specific lectins (e.g., Ulex europaeus agglutinin I) to murine Peyer's patch M cells.
• Differential lectin binding patterns observed in rabbit caecal patch M cells and Peyer's patch enterocytes.

Main Results:

• Ulex europaeus agglutinin I selectively bound to M cells in murine Peyer's patches but not in mouse caecal patches.
• Ulex europaeus agglutinin I, wheat germ agglutinin, peanut agglutinin, and Bandeiraea simplicifolia agglutinin II showed selective binding to rabbit caecal patch M cells.
• Distinct lectin binding profiles highlight significant regional and species-specific differences in M cell surface glycoconjugates.

Conclusions:

• M cell surface glycoconjugate expression exhibits marked regional and species variation.
• These variations influence the normal antigen-sampling function of M cells.
• Findings provide insights for the rational design of particulates for transepithelial delivery via the M cell portal.