title: Effects on antigen-presenting cells of short-term interaction with the human host defence peptide β-defensin 2.
abstract: β-Defensins are antimicrobial peptides that exert their host-defence functions at the interface between the host and microbial biota. They display a direct, salt- and medium-sensitive cidal activity, in vitro, against a broad spectrum of bacteria and fungi, and there is increasing evidence that they also play a role in alerting and enhancing cellular components of innate and adaptive immunity. Their interaction with biological membranes plays a central role in both of these types of activities. In the present study, we have investigated the interaction of fluorescently labelled hBD2 (human β-defensin 2) with monocytes, macrophages and iDCs (immature dendritic cells), observing a differential capacity to be rapidly internalized into these cells. Complementary microscopy techniques [TEM (transmission electron microscopy), optical microscopy and IR microspectroscopy] were used to explore the functional and biological implications of these interactions on iDCs. Short-term exposure to the peptide resulted in significant alterations in membrane composition and re-organization of the endomembrane system, with the induction of degranulation. These events may be associated with the antigen-presenting activities or the chemotaxis of iDCs, which appears to occur via both CCR6 (CC chemokine receptor 6)-dependent and -independent mechanisms.
authors: Department of Life Sciences, University of Trieste, Trieste 34127, Italy.
authors: Francesca
authors: F
authors: Morgera
authors: Sabrina
authors: S
authors: Pacor
authors: Luisa
authors: L
authors: Creatti
authors: Nikolinka
authors: N
authors: Antcheva
authors: Lisa
authors: L
authors: Vaccari
authors: Alessandro
authors: A
authors: Tossi
mesh_terms: D000938:Antigen-Presenting Cells / Q000187:drug effects* / Q000276:immunology / Q000528:radiation effects; D002634:Chemotaxis, Leukocyte / Q000187:drug effects / Q000502:physiology; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology; D005434:Flow Cytometry; D006801:Humans; D007259:Infrared Rays; D018613:Microscopy, Confocal; D015591:Microspectrophotometry; D017356:Synchrotrons; D023083:beta-Defensins / Q000494:pharmacology*
chemical_list: C106641:DEFB4A protein, human; D023083:beta-Defensins