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Updated: Jun 2, 2026
07:15
Invasion of Human Cells by a Bacterial Pathogen
Published on: March 21, 2011
Integrin-mediated uptake of fibronectin-binding bacteria.
Christine Hoffmann1, Knut Ohlsen, Christof R Hauck
1Lehrstuhl Zellbiologie, Universität Konstanz, Germany.
European Journal of Cell Biology
|May 13, 2011
Summary
Staphylococcus aureus uses fibronectin-binding proteins (FnBPs) to invade host cells by engaging integrins. Cholesterol-rich microdomains and caveolin-1 influence this bacterial invasion process.
Area of Science:
- Microbiology
- Cell Biology
- Pathogenesis
Background:
- Bacterial pathogens frequently invade mammalian cells using host cell adhesion molecules, particularly integrins.
- Staphylococcus aureus employs fibronectin-binding proteins (FnBPs) to indirectly engage host cell integrins for invasion.
Purpose of the Study:
- To review the structure-function of FnBPs and their role in bacterial pathogenesis.
- To highlight recent findings on the involvement of membrane microdomains and caveolin-1 in S. aureus invasion.
Main Methods:
- Literature review focusing on structure-function relationships of FnBPs.
- Analysis of studies investigating host cell invasion mechanisms by fibronectin-binding bacteria.
Main Results:
- FnBPs are crucial for Staphylococcus aureus to bind fibronectin and subsequently engage integrins.
- Cholesterol- and sphingolipid-rich membrane microdomains play a significant role in integrin-mediated bacterial uptake.
- Caveolin-1 unexpectedly inhibits the process of integrin-initiated bacterial invasion.
Conclusions:
- Understanding S. aureus invasion via FnBPs provides a model for other fibronectin-binding pathogens.
- Mechanistic insights into this process may elucidate the regulation of integrin endocytosis.
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