Infection with Campylobacter jejuni induces tyrosine-phosphorylated proteins into INT-407 cells

Area of Science:

• Microbiology
• Cell Biology
• Infectious Diseases

Background:

• The precise mechanisms by which Campylobacter jejuni invades host intestinal epithelial cells remain largely undefined.
• Understanding bacterial internalization pathways is crucial for developing strategies to combat C. jejuni infections.

Purpose of the Study:

• To investigate the role of protein kinases in the invasion of INT-407 intestinal cells by Campylobacter jejuni.
• To identify specific host cell signaling pathways involved in C. jejuni internalization.

Main Methods:

• INT-407 cells were treated with various protein kinase inhibitors (staurosporine, tyrphostin 46, genistein) in a dose-dependent manner.
• Bacterial invasion assays were performed to quantify C. jejuni entry into treated and untreated cells.
• Western blotting was used to analyze tyrosine phosphorylation of host cell proteins following C. jejuni infection and kinase inhibitor treatment.

Main Results:

• Exposure to protein kinase inhibitors significantly reduced C. jejuni invasion of INT-407 cells.
• Genistein treatment notably decreased bacterial internalization.
• C. jejuni infection induced tyrosine phosphorylation of specific host proteins (170, 145, 90, 60, 55 kDa), which was diminished by genistein pretreatment.

Conclusions:

• Tyrosine protein kinase-dependent signaling pathways play a critical role in regulating Campylobacter jejuni internalization into intestinal epithelial cells.
• These findings elucidate a key host-pathogen interaction mechanism governing C. jejuni pathogenesis.