Cargando…

The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis

SIMPLE SUMMARY: The study identified a new spliced isoform of anionic β-defensin from flounder (Paralichthys olivaceus, fBD) and examined its antibiosis, chemotaxis and modulation of phagocytosis. It also analyzed the contributions of fBD to the antimicrobial activity of extracellular traps (ETs). T...

Descripción completa

Detalles Bibliográficos
Autores principales: Hao, Xiaokai, Chi, Heng, Tang, Xiaoqian, Xing, Jing, Sheng, Xiuzhen, Zhan, Wenbin
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8698591/
https://www.ncbi.nlm.nih.gov/pubmed/34943162
http://dx.doi.org/10.3390/biology10121247
_version_ 1784620313739264000
author Hao, Xiaokai
Chi, Heng
Tang, Xiaoqian
Xing, Jing
Sheng, Xiuzhen
Zhan, Wenbin
author_facet Hao, Xiaokai
Chi, Heng
Tang, Xiaoqian
Xing, Jing
Sheng, Xiuzhen
Zhan, Wenbin
author_sort Hao, Xiaokai
collection PubMed
description SIMPLE SUMMARY: The study identified a new spliced isoform of anionic β-defensin from flounder (Paralichthys olivaceus, fBD) and examined its antibiosis, chemotaxis and modulation of phagocytosis. It also analyzed the contributions of fBD to the antimicrobial activity of extracellular traps (ETs). The analyses found that an anionic β-defensin in fish possesses strong bacteriostatic ability in line with that of cationic defensins and also plays an important role in immune response. This study provides new insights into the biological function of anionic defensins, which can serve as one of the important effectors in extracellular traps and contribute to the immune response. ABSTRACT: Most defensins are cationic antimicrobial peptides with broad-spectrum killing activity against bacteria, fungi and enveloped viruses. However, it should be recognized that there are some non-cationic β-defensins in organisms, which need to be further studied. In this study, a new spliced isoform of anionic β-defensin from flounder (Paralichthys olivaceus, fBD) was identified, and its antibiosis, chemotaxis and modulation of phagocytosis were examined. In addition, the contributions of fBD to the antimicrobial activity of extracellular traps (ETs) were also analyzed. The recombinant fBD (rfBD) could effectively inhibit the growth of Gram-positive bacteria (S. aureus, Micrococcus luteus) and Gram-negative bacteria (E. coli, V. alginolyticus, V. anguillarum). An indirect immunofluorescence assay showed that the fBD was co-localized in the extracellular traps released by the leukocytes. When the ETs were blocked with antibodies against rfBD, the proliferation of S. aureus and E. coli incubated with ETs tended to increase compared with that in the control group. In addition, the results obtained by flow cytometry showed that the rfBD could significantly chemoattract leukocytes and increase phagocytic activity in vitro. In conclusion, this study provides new insights into the biological function of anionic defensins, which can serve as one of the important effectors in extracellular traps and as a bridge between innate and adaptive immunity in teleosts.
format Online
Article
Text
id pubmed-8698591
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-86985912021-12-24 The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis Hao, Xiaokai Chi, Heng Tang, Xiaoqian Xing, Jing Sheng, Xiuzhen Zhan, Wenbin Biology (Basel) Article SIMPLE SUMMARY: The study identified a new spliced isoform of anionic β-defensin from flounder (Paralichthys olivaceus, fBD) and examined its antibiosis, chemotaxis and modulation of phagocytosis. It also analyzed the contributions of fBD to the antimicrobial activity of extracellular traps (ETs). The analyses found that an anionic β-defensin in fish possesses strong bacteriostatic ability in line with that of cationic defensins and also plays an important role in immune response. This study provides new insights into the biological function of anionic defensins, which can serve as one of the important effectors in extracellular traps and contribute to the immune response. ABSTRACT: Most defensins are cationic antimicrobial peptides with broad-spectrum killing activity against bacteria, fungi and enveloped viruses. However, it should be recognized that there are some non-cationic β-defensins in organisms, which need to be further studied. In this study, a new spliced isoform of anionic β-defensin from flounder (Paralichthys olivaceus, fBD) was identified, and its antibiosis, chemotaxis and modulation of phagocytosis were examined. In addition, the contributions of fBD to the antimicrobial activity of extracellular traps (ETs) were also analyzed. The recombinant fBD (rfBD) could effectively inhibit the growth of Gram-positive bacteria (S. aureus, Micrococcus luteus) and Gram-negative bacteria (E. coli, V. alginolyticus, V. anguillarum). An indirect immunofluorescence assay showed that the fBD was co-localized in the extracellular traps released by the leukocytes. When the ETs were blocked with antibodies against rfBD, the proliferation of S. aureus and E. coli incubated with ETs tended to increase compared with that in the control group. In addition, the results obtained by flow cytometry showed that the rfBD could significantly chemoattract leukocytes and increase phagocytic activity in vitro. In conclusion, this study provides new insights into the biological function of anionic defensins, which can serve as one of the important effectors in extracellular traps and as a bridge between innate and adaptive immunity in teleosts. MDPI 2021-11-29 /pmc/articles/PMC8698591/ /pubmed/34943162 http://dx.doi.org/10.3390/biology10121247 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Hao, Xiaokai
Chi, Heng
Tang, Xiaoqian
Xing, Jing
Sheng, Xiuzhen
Zhan, Wenbin
The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis
title The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis
title_full The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis
title_fullStr The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis
title_full_unstemmed The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis
title_short The Functions of β-Defensin in Flounder (Paralichthys olivaceus): Antibiosis, Chemotaxis and Modulation of Phagocytosis
title_sort functions of β-defensin in flounder (paralichthys olivaceus): antibiosis, chemotaxis and modulation of phagocytosis
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8698591/
https://www.ncbi.nlm.nih.gov/pubmed/34943162
http://dx.doi.org/10.3390/biology10121247
work_keys_str_mv AT haoxiaokai thefunctionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT chiheng thefunctionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT tangxiaoqian thefunctionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT xingjing thefunctionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT shengxiuzhen thefunctionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT zhanwenbin thefunctionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT haoxiaokai functionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT chiheng functionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT tangxiaoqian functionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT xingjing functionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT shengxiuzhen functionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis
AT zhanwenbin functionsofbdefensininflounderparalichthysolivaceusantibiosischemotaxisandmodulationofphagocytosis