Antimicrobial peptides and atopic dermatitis

Our skin is constantly challenged by microbes but is rarely infected.

How is that possible?

Cutaneous production of antimicrobial peptides (AMPs) is a primary system for protection. Antimicrobial peptides (AMP) are ubiquitous cationic proteins that play a role in innate immunity.

Cathelicidins are unique AMPs that protect the skin through 2 pathways:

- antimicrobial activity
- cytokine release, inflammation, angiogenesis, and reepithelialization

Cathelicidin dysfunction may be a central factor in the pathogenesis of several cutaneous diseases:

- atopic dermatitis - cathelicidin is suppressed. AMPs are decreased under the influence of TH2 cells. Atopic dermatitis patients are susceptible to Staphylococcus aureus due to a decrease in AMP. S. aureus (enterotoxins), M sympodialis, and allergens are trigger factors of atopic dermatitis - they stimulate dendritic cells (JACI, 2012).

- rosacea - cathelicidin is abnormally processed to induce inflammation

- psoriasis - cathelicidin converts self-DNA to stimulate an autoinflammatory cascade

Vitamin D3 is as a major factor involved in the regulation of cathelicidin.

Therapies targeting cathelicidin and other AMPs might be beneficial in inflammatory skin diseases.



Atopic Dermatitis Treatment - Illustrated (click here for full size image).

References:

Antimicrobial peptides and the skin immune defense system. Schauber J, Gallo RL. J Allergy Clin Immunol. 2009 Sep;124(3S2):R13-R18.
Extracellular vesicles derived from Staphylococcus aureus induce atopic dermatitis-like skin inflammation http://goo.gl/Evqr
Image source: The modes of action by Antimicrobial peptides. Wikipedia, Ymahn, Creative Commons Attribution-ShareAlike 3.0 License.

No comments:

Post a Comment

Blog Widget by LinkWithin