Fibronectin attachment protein is necessary for efficient attachment and invasion of epithelial cells by...

Area of Science:

• Microbiology
• Cell Biology
• Immunology

Background:

• Mycobacterium avium subsp. paratuberculosis (MAP) is an important pathogen.
• Epithelial cells form a barrier against pathogens but can be entry points.
• Fibronectin (FN) is an extracellular matrix protein involved in cell adhesion and pathogen interactions.

Purpose of the Study:

• To investigate the role of fibronectin (FN) in the attachment and ingestion of Mycobacterium avium subsp. paratuberculosis (MAP) by epithelial cells.
• To determine the specific contribution of the FN attachment protein (FAP-P) in this interaction.

Main Methods:

• Utilized two epithelial cell lines (T-24 and Caco-2).
• Assessed the effect of soluble fibronectin (FN) on MAP attachment and ingestion.
• Employed peptide blocking of the FN attachment protein (FAP-P) and disruption of FAP-P expression to evaluate its role.

Main Results:

• Soluble fibronectin (FN) significantly enhanced the attachment and ingestion of MAP by epithelial cells.
• Peptide blocking of the FN attachment protein (FAP-P) effectively inhibited MAP internalization.
• Disruption of FAP-P expression markedly reduced both MAP attachment and ingestion by T-24 and Caco-2 cells.

Conclusions:

• The interaction between fibronectin (FN) and the FN attachment protein (FAP-P) is crucial for MAP attachment and entry into epithelial cells.
• FAP-P acts as a key mediator facilitating MAP's interaction with and invasion of host epithelial cells.
• Targeting the FN-FAP-P pathway could offer novel strategies for controlling MAP infections.