Defensins – an Important Component of Natural Immunity in Defense against Infection
Authors:
Z. Kuchynková 1; H. Pácová 1,2
Authors place of work:
Klinika otorinolaryngologie a chirurgie hlavy a krku 1. LF UK a FN Motol
Katedra otolaryngologie IPVZ, Praha
; přednosta prof. MUDr. J. Betka, DrSc.
Ústav pro histologii a embryologii, 1. LF UK, Praha
1; přednosta doc. MUDr. P. Hach, DrSc.
2
Published in the journal:
Otorinolaryngol Foniatr, 57, 2008, No. 1, pp. 36-39.
Category:
Comprehensive Reports
Summary
Defensins are antimicrobial and immunomodulation peptides, which are the important part of natural immunity. The authors briefly characterize natural immunity, chemical structure and function of defensins. The review deals preferentially with human defensins on respiratory mucous membranes and their effects on bacteria, mainly on gram-negative Staphylococcus aureus.
Defensins exert a direct destructive effect on bacterial wall, but they possess an immunomodulation effect as well. Human defensins are divided according to their structure to alpha, beta 1, beta 2, beta 3 and beta 4. Alpha defensins are in granulocytes, in mucosa of urogenital and intestinal tract. Beta defensins are in all epithelial tissues. In the epithelium of respiratory pathways beta defensins 1 are produced constitutively and beta defensins 2 and 3 are induced as a response to infection agents.
Some bacteria can modify their wall and thereby become less sensitive to defensins. In the bacteria Staphylococcus aureus the genes Dlt and Mrpf were found responsible for modification of teichoic acid and phosphatidylglycerol in the membrane in such a way that it decreases attractiveness of the bacteria for the positively charged defensins. Defects in these genes caused increased sensitivity of this bacterium to defensins.
New knowledge of antibacterial peptides helps us to understand better infectious diseases and offers new perspectives in the therapy of these diseases.
Key words:
defensins, respiratory tract, Staphylococcus aureus.
Zdroje
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Štítky
Audiology Paediatric ENT ENT (Otorhinolaryngology)Článok vyšiel v časopise
Otorhinolaryngology and Phoniatrics
2008 Číslo 1
Najčítanejšie v tomto čísle
- Evaluation of Hearing and Speech Treatment by Means of Phonological Awareness Test and Dichotic Tests
- Defensins – an Important Component of Natural Immunity in Defense against Infection
- Evaluation of Dysphagia, Treatment Possibilities of the Patient with Dysphagia at the ENT Departments in the Czech and Slovak Republics
- Cleft Defects and Their Role in the Origin of Chronic Otitis in Older Children and Adolescents