In:
Journal of Leukocyte Biology, Oxford University Press (OUP), Vol. 89, No. 2 ( 2010-11-17), p. 283-290
Abstract:
Mammalian defensins are cationic, antimicrobial peptides that play a central role in innate immunity. The peptides are composed of three structural subfamilies: α-, β-, and θ-defensins. θ-Defensins are macrocyclic octadecapeptides expressed only in Old World monkeys and Orangutans and are produced by the pair-wise, head-to-tail splicing of nonapeptides derived from their respective precursors. The existence of three active θ-defensin genes predicts that six different RTDs (1–6) are produced in this species. In this study, we isolated and quantified RTDs 1–6 from the neutrophils of 10 rhesus monkeys. RTD-1 was the most abundant θ-defensin, constituting ∼50% of the RTD content; total RTD content varied by as much as threefold between animals. All peptides tested were microbicidal at ∼1 μM concentrations. The contribution of θ-defensins to macaque neutrophil antimicrobial activity was assessed by analyzing the microbicidal properties of neutrophil granule extracts after neutralizing θ-defensin content with a specific antibody. θ-Defensin neutralization markedly reduced microbicidal activities of the corresponding extracts. Macaque neutrophil granule extracts had significantly greater microbicidal activity than those of human neutrophils, which lack θ-defensins. Supplementation of human granule extracts with RTD-1 markedly increased the microbicidal activity of these preparations, further demonstrating a prominent microbicidal role for θ-defensins.
Type of Medium:
Online Resource
ISSN:
0741-5400
,
1938-3673
Language:
English
Publisher:
Oxford University Press (OUP)
Publication Date:
2010
detail.hit.zdb_id:
2026833-6
SSG:
12
