Bacterial Toxins as Pathogen Weapons Against Phagocytes
Ana do Vale1, Didier Cabanes2, Sandra Sousa2
1Host Interaction and Response, Instituto de Investigação e Inovação em Saúde, Universidade do PortoPorto, Portugal; Group of Fish Immunology and Vaccinology, Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal.
Frontiers in Microbiology
|February 13, 2016
Summary
Bacterial toxins disable key immune cells like macrophages and neutrophils. This review explores how these toxins, from Gram-positive and Gram-negative bacteria, disrupt host defenses and promote infection.
Area of Science:
- Microbiology
- Immunology
- Toxicology
Background:
- Bacterial toxins are crucial virulence factors.
- They manipulate host cell functions to facilitate infection.
- Some toxins specifically target innate immune cells, impairing host defense.
Purpose of the Study:
- To review bacterial toxins that act extracellularly.
- To focus on toxins affecting macrophages and neutrophils.
- To discuss mechanisms of immune cell manipulation and host outcomes.
Main Methods:
- Literature review of bacterial toxins.
- Focus on toxins from Gram-positive and Gram-negative bacteria.
- Analysis of toxins targeting extracellularly and impacting innate immunity.
Main Results:
- Extracellular bacterial toxins impair macrophage and neutrophil function.
- Toxins employ diverse strategies including cell signaling manipulation and cell death induction.
- Mechanisms involve direct cytoplasmic membrane damage or enzymatic modification of eukaryotic targets.
Conclusions:
- Bacterial toxins significantly compromise innate immunity by targeting phagocytic cells.
- Understanding these toxins is key to comprehending pathogen dissemination and disease progression.
- This review highlights the critical role of extracellular toxins in bacterial pathogenesis.
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