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Determination of Biofilm Initiation on Virus-infected Cells by Bacteria and Fungi
Published on: July 6, 2016
Host-pathogen interplay of Haemophilus ducreyi
Diane M Janowicz1, Wei Li, Margaret E Bauer
1Department of Medicine, Indiana University School of Medicine, Indianapolis, Indiana 46202-5124, USA.
Current Opinion in Infectious Diseases
|November 18, 2009
Summary
Haemophilus ducreyi, a cause of chancroid, uses virulence factors to evade immune responses. Host immune cells like dendritic cells and NK cells may influence infection outcomes, impacting disease persistence.
Area of Science:
- Microbiology
- Immunology
- Dermatology
Background:
- Haemophilus ducreyi is the bacterial agent responsible for chancroid, a sexually transmitted infection primarily affecting human skin.
- During infection, H. ducreyi survives extracellularly amidst host immune cells and antibacterial factors.
- Understanding the host-pathogen interaction is crucial for explaining disease development and persistence.
Purpose of the Study:
- To review the interplay between Haemophilus ducreyi and its human host.
- To summarize virulence mechanisms employed by H. ducreyi to counteract host defenses.
- To explore the role of the host immune system in determining infection outcomes.
Main Methods:
- Review of existing literature on Haemophilus ducreyi virulence and host immune response.
- Analysis of identified virulence factors and their functions.
- Examination of immune cell involvement in H. ducreyi infections.
Main Results:
- H. ducreyi employs virulence factors like LspA proteins and DsrA for immune evasion.
- An influx transporter confers resistance to the antimicrobial peptide LL37.
- Host kinases phosphorylate LspA, potentially aiding antiphagocytic functions.
- Dendritic cells and natural killer cells are implicated in differential infection outcomes.
Conclusions:
- A human infection model reveals H. ducreyi's strategies for surviving host immune pressure.
- Innate immune components critically influence whether H. ducreyi infection is cleared or progresses to disease.
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