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Lyu Z, Yang P, Lei J, Zhao J. Biological Function of Antimicrobial Peptides on Suppressing Pathogens and Improving Host Immunity. Antibiotics (Basel) 2023; 12:1037. [PMID: 37370356 DOI: 10.3390/antibiotics12061037] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/04/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
The emergence of drug-resistant genes and concerns about food safety caused by the overuse of antibiotics are becoming increasingly prominent. There is an urgent need for effective alternatives to antibiotics in the fields of livestock production and human medicine. Antimicrobial peptides can effectively replace antibiotics to kill pathogens and enhance the immune functions of the host, and pathogens cannot easily produce genes that are resistant to them. The ability of antimicrobial peptides (AMPs) to kill pathogens is associated with their structure and physicochemical properties, such as their conformation, electrical charges, hydrophilicity, and hydrophobicity. AMPs regulate the activity of immunological cells and stimulate the secretion of inflammatory cytokines via the activation of the NF-κB and MAPK signaling pathways. However, there are still some limitations to the application of AMPs in the fields of livestock production and human medicine, including a restricted source base, high costs of purification and expression, and the instability of the intestines of animals and humans. This review summarizes the information on AMPs as effective antibiotic substitutes to improve the immunological functions of the host through suppressing pathogens and regulating inflammatory responses. Potential challenges for the commercial application of AMPs in animal husbandry and human medicine are discussed.
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Affiliation(s)
- Zhiqian Lyu
- Guangdong Haid Group Co., Ltd., Guangzhou 511400, China
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Pan Yang
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Jian Lei
- Guangdong Haid Group Co., Ltd., Guangzhou 511400, China
- Qingyuan Haibei BIO-TECH Co., Ltd., Qingyuan 511853, China
| | - Jinbiao Zhao
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
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2
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Zhang Q, Ul Ain Q, Schulz C, Pircher J. Role of antimicrobial peptide cathelicidin in thrombosis and thromboinflammation. Front Immunol 2023; 14:1151926. [PMID: 37090695 PMCID: PMC10114025 DOI: 10.3389/fimmu.2023.1151926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 03/24/2023] [Indexed: 04/09/2023] Open
Abstract
Thrombosis is a frequent cause of cardiovascular mortality and hospitalization. Current antithrombotic strategies, however, target both thrombosis and physiological hemostasis and thereby increase bleeding risk. In recent years the pathophysiological understanding of thrombus formation has significantly advanced and inflammation has become a crucial element. Neutrophils as most frequent immune cells in the blood and their released mediators play a key role herein. Neutrophil-derived cathelicidin next to its strong antimicrobial properties has also shown to modulates thrombosis and thus presents a potential therapeutic target. In this article we review direct and indirect (immune- and endothelial cell-mediated) effects of cathelicidin on platelets and the coagulation system. Further we discuss its implications for large vessel thrombosis and consecutive thromboinflammation as well as immunothrombosis in sepsis and COVID-19 and give an outlook for potential therapeutic prospects.
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Affiliation(s)
- Qing Zhang
- Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Ludwig-Maximilians- Universität, Munich, Germany
- Partner Site Munich Heart Alliance, DZHK (German Centre for Cardiovascular Research), Munich, Germany
| | - Qurrat Ul Ain
- Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Ludwig-Maximilians- Universität, Munich, Germany
| | - Christian Schulz
- Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Ludwig-Maximilians- Universität, Munich, Germany
- Partner Site Munich Heart Alliance, DZHK (German Centre for Cardiovascular Research), Munich, Germany
| | - Joachim Pircher
- Medizinische Klinik und Poliklinik I, Klinikum der Universität München, Ludwig-Maximilians- Universität, Munich, Germany
- Partner Site Munich Heart Alliance, DZHK (German Centre for Cardiovascular Research), Munich, Germany
- *Correspondence: Joachim Pircher,
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3
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Amagai R, Takahashi T, Terui H, Fujimura T, Yamasaki K, Aiba S, Asano Y. The Antimicrobial Peptide Cathelicidin Exerts Immunomodulatory Effects via Scavenger Receptors. Int J Mol Sci 2023; 24:ijms24010875. [PMID: 36614313 PMCID: PMC9821026 DOI: 10.3390/ijms24010875] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 12/20/2022] [Accepted: 12/21/2022] [Indexed: 01/05/2023] Open
Abstract
An active form of cathelicidin antimicrobial peptide, LL-37, has immunomodulatory and stimulatory effects, though the specific pathways are not clear. The purpose of this study was to identify the cellular pathways by which LL-37 amplifies the inflammation induced by damage-associated molecular patterns (DAMPs). We performed DNA microarray, reverse transcription polymerase chain reaction, immunoblotting, and proximity ligation assays using cultured keratinocytes treated with LL-37 and/or the DAMP poly(I:C), a synthetic double-stranded RNA. In contrast to the combination of LL-37 and poly(I:C), LL-37 alone induced genes related to biological metabolic processes such as VEGFA and PTGS2 (COX-2). Inhibition of FPR2, a known receptor for cathelicidin, partially suppressed the induction of VEGFA and PTGS2. Importantly, VEGFA and PTGS2 induced by LL-37 alone were diminished by the knockdown of scavenger receptors including SCARB1 (SR-B1), OLR1 (SR-E1), and AGER (SR-J1). Moreover, LL-37 alone, as well as the combination of LL-37 and poly(I:C), showed proximity to the scavenger receptors, indicating that LL-37 acts via scavenger receptors and intermediates between them and poly(I:C). These results showed that the broad function of cathelicidin is generally dependent on scavenger receptors. Therefore, inhibitors of scavenger receptors or non-functional mock cathelicidin peptides may serve as new anti-inflammatory and immunosuppressive agents.
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4
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Ali W, Elsahn A, Ting DSJ, Dua HS, Mohammed I. Host Defence Peptides: A Potent Alternative to Combat Antimicrobial Resistance in the Era of the COVID-19 Pandemic. Antibiotics (Basel) 2022; 11:475. [PMID: 35453226 PMCID: PMC9032040 DOI: 10.3390/antibiotics11040475] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/21/2022] [Accepted: 03/24/2022] [Indexed: 12/07/2022] Open
Abstract
One of the greatest challenges facing the medical community today is the ever-increasing trajectory of antimicrobial resistance (AMR), which is being compounded by the decrease in our antimicrobial armamentarium. From their initial discovery to the current day, antibiotics have seen an exponential increase in their usage, from medical to agricultural use. Benefits aside, this has led to an exponential increase in AMR, with the fear that over 10 million lives are predicted to be lost by 2050, according to the World Health Organisation (WHO). As such, medical researchers are turning their focus to discovering novel alternatives to antimicrobials, one being Host Defence Peptides (HDPs). These small cationic peptides have shown great efficacy in being used as an antimicrobial therapy for currently resistant microbial variants. With the sudden emergence of the SARS-CoV-2 variant and the subsequent global pandemic, the great versatility and potential use of HDPs as an alternative to conventional antibiotics in treating as well as preventing the spread of COVID-19 has been reviewed. Thus, to allow the reader to have a full understanding of the multifaceted therapeutic use of HDPs, this literature review shall cover the association between COVID-19 and AMR whilst discussing and evaluating the use of HDPs as an answer to antimicrobial resistance (AMR).
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Affiliation(s)
| | | | | | | | - Imran Mohammed
- Section of Ophthalmology, Larry A. Donoso Laboratory for Eye Research, Academic Unit of Mental Health and Clinical Neuroscience, School of Medicine, University of Nottingham, Queens Medical Centre, Eye and ENT Building, Nottingham NG7 2UH, UK; (W.A.); (A.E.); (D.S.J.T.); (H.S.D.)
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5
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Bodahl S, Cerps S, Uller L, Nilsson BO. LL-37 and Double-Stranded RNA Synergistically Upregulate Bronchial Epithelial TLR3 Involving Enhanced Import of Double-Stranded RNA and Downstream TLR3 Signaling. Biomedicines 2022; 10:biomedicines10020492. [PMID: 35203701 PMCID: PMC8962275 DOI: 10.3390/biomedicines10020492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/08/2022] [Accepted: 02/17/2022] [Indexed: 12/15/2022] Open
Abstract
The human host defense peptide LL-37 influences double-stranded RNA signaling, but this process is not well understood. Here, we investigate synergistic actions of LL-37 and synthetic double-stranded RNA (poly I:C) on toll-like receptor 3 (TLR3) expression and signaling, and examine underlying mechanisms. In bronchial epithelial BEAS-2B cells, LL-37 potentiated poly I:C-induced TLR3 mRNA and protein expression demonstrated by qPCR and Western blot, respectively. Interestingly, these effects were associated with increased uptake of rhodamine-tagged poly I:C visualized by immunocytochemistry. The LL-37/poly I:C-induced upregulation of TLR3 mRNA expression was prevented by the endosomal acidification inhibitor chloroquine, indicating involvement of downstream TLR3 signaling. The glucocorticoid dexamethasone reduced LL-37/poly I:C-induced TLR3 expression on both mRNA and protein levels, and this effect was associated with increased IκBα protein expression, suggesting that dexamethasone acts via attenuation of NF-κB activity. We conclude that LL-37 potentiates poly I:C-induced upregulation of TLR3 through a mechanism that may involve enhanced import of poly I:C and that LL-37/poly I:C-induced TLR3 expression is associated with downstream TLR3 signaling and sensitive to inhibition of NF-κB activity.
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6
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Galler KM, Weber M, Korkmaz Y, Widbiller M, Feuerer M. Inflammatory Response Mechanisms of the Dentine-Pulp Complex and the Periapical Tissues. Int J Mol Sci 2021; 22:ijms22031480. [PMID: 33540711 PMCID: PMC7867227 DOI: 10.3390/ijms22031480] [Citation(s) in RCA: 126] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/25/2021] [Accepted: 01/28/2021] [Indexed: 02/08/2023] Open
Abstract
The macroscopic and microscopic anatomy of the oral cavity is complex and unique in the human body. Soft-tissue structures are in close interaction with mineralized bone, but also dentine, cementum and enamel of our teeth. These are exposed to intense mechanical and chemical stress as well as to dense microbiologic colonization. Teeth are susceptible to damage, most commonly to caries, where microorganisms from the oral cavity degrade the mineralized tissues of enamel and dentine and invade the soft connective tissue at the core, the dental pulp. However, the pulp is well-equipped to sense and fend off bacteria and their products and mounts various and intricate defense mechanisms. The front rank is formed by a layer of odontoblasts, which line the pulp chamber towards the dentine. These highly specialized cells not only form mineralized tissue but exert important functions as barrier cells. They recognize pathogens early in the process, secrete antibacterial compounds and neutralize bacterial toxins, initiate the immune response and alert other key players of the host defense. As bacteria get closer to the pulp, additional cell types of the pulp, including fibroblasts, stem and immune cells, but also vascular and neuronal networks, contribute with a variety of distinct defense mechanisms, and inflammatory response mechanisms are critical for tissue homeostasis. Still, without therapeutic intervention, a deep carious lesion may lead to tissue necrosis, which allows bacteria to populate the root canal system and invade the periradicular bone via the apical foramen at the root tip. The periodontal tissues and alveolar bone react to the insult with an inflammatory response, most commonly by the formation of an apical granuloma. Healing can occur after pathogen removal, which is achieved by disinfection and obturation of the pulp space by root canal treatment. This review highlights the various mechanisms of pathogen recognition and defense of dental pulp cells and periradicular tissues, explains the different cell types involved in the immune response and discusses the mechanisms of healing and repair, pointing out the close links between inflammation and regeneration as well as between inflammation and potential malignant transformation.
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Affiliation(s)
- Kerstin M. Galler
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, 93093 Regensburg, Germany;
- Correspondence:
| | - Manuel Weber
- Department of Oral and Maxillofacial Surgery, Friedrich-Alexander University Erlangen-Nürnberg, 91054 Erlangen, Germany;
| | - Yüksel Korkmaz
- Department of Periodontology and Operative Dentistry, University of Mainz, 55131 Mainz, Germany;
| | - Matthias Widbiller
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, 93093 Regensburg, Germany;
| | - Markus Feuerer
- Department for Immunology, University Hospital Regensburg, 93053 Regensburg, Germany;
- Regensburg Center for Interventional Immunology (RCI), University Hospital Regensburg, 93053 Regensburg, Germany
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7
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Cai S, Lu C, Liu Z, Wang W, Lu S, Sun Z, Wang G. Derivatives of gecko cathelicidin-related antioxidant peptide facilitate skin wound healing. Eur J Pharmacol 2021; 890:173649. [PMID: 33049300 DOI: 10.1016/j.ejphar.2020.173649] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/05/2020] [Accepted: 10/09/2020] [Indexed: 12/28/2022]
Abstract
Cathelicidins are a class of gene-encoded multifunctional factors in host defence systems. They have recently attracted a great deal of attention as promising drug candidates. Cathelicidins are well studied in vertebrates, yet no studies have been reported concerning gecko cathelicidin. Recently, we identified a novel cathelicidin from Gekko japonicus, Gj-CATH3. Unlike most cathelicidins, Gj-CATH3 exhibits potent antioxidant activity in vitro. Unfortunately, slight toxicity and high synthesis cost restrict its application. Thus, we designed a series of Gj-CATH3 analogues for development of short peptides with improved cell selectivity. Functional analysis showed that two truncated peptides, Gj-CATH3-(38-42)-peptide and Gj-CATH3-(33-42)-peptide, exhibited excellent antioxidant activity against ABTS and DPPH free radicals. Further, cytotoxicity and hemolytic activities were observably lower compared to Gj-CATH3. Interestingly, both peptides also demonstrate significant wound healing properties in a mouse model with full-thickness skin wounds. The peptides induce HaCaT cell proliferation and prevent decreases in SOD activity and increases of MDA concentration in injured-skin tissue. This report is the first to address cathelicidin from reptilia that exhibit potent wound healing activity. Our research will enrich understanding of cathelicidin biological functions, and provide a theoretical basis for its clinical application.
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Affiliation(s)
- Shasha Cai
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China.
| | - Changao Lu
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China
| | - Zhenlei Liu
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China
| | - Wenbo Wang
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China
| | - Shuxin Lu
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China
| | - Zhaoxing Sun
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China
| | - Guannan Wang
- College of Medical Engineering & the Key Laboratory for Medical Functional Nanomaterials, Jining Medical University, Jining, 272067, China.
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8
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Bankell E, Dahl S, Gidlöf O, Svensson D, Nilsson BO. LL-37-induced caspase-independent apoptosis is associated with plasma membrane permeabilization in human osteoblast-like cells. Peptides 2021; 135:170432. [PMID: 33129893 DOI: 10.1016/j.peptides.2020.170432] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 11/20/2022]
Abstract
The host defense peptide LL-37 is active against both gram-positive and gram-negative bacteria, but it has also been shown to reduce human host cell viability. However, the mechanisms behind LL-37-induced human host cell cytotoxicity are not yet fully understood. Here, we assess if LL-37-evoked attenuation of human osteoblast-like MG63 cell viability is associated with apoptosis, and if the underlying mechanism may involve LL-37-induced plasma membrane permeabilization. MG63 cell viability and plasma membrane permeabilization were investigated by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method and by measuring lactate dehydrogenase (LDH) release, respectively. Apoptosis was assessed by the terminal deoxynucleotidyl dUTP nick end labeling (TUNEL) assay and Annexin V flow cytometry, and caspase-3 and poly (ADP-ribose) polymerase (PARP) cleavage were determined by Western blot. LL-37 (4 and 10 μM) reduced both cell number and cell viability, and these effects were associated with a pro-apoptotic effect demonstrated by positive TUNEL staining and Annexin V flow cytometry. LL-37-induced apoptosis was not coupled to either caspase-3 or PARP cleavage, suggesting that LL-37 causes caspase-independent apoptosis in MG63 cells. Both LL-37 and the well-known plasma membrane permeabilizer Triton X-100 reduced cell viability and stimulated LDH release. Triton X-100-treated cells showed positive TUNEL staining, and the detergent accumulated cells in late apoptosis/necrosis. Similar to LL-37, Triton X-100 caused no PARP cleavage. We conclude that LL-37 promotes caspase-independent apoptosis, and that this effect seems coupled to plasma membrane permeabilization in human MG63 cells.
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Affiliation(s)
- Elisabeth Bankell
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Sara Dahl
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Olof Gidlöf
- Department of Cardiology, Clinical Sciences, Lund University, Skåne University Hospital, Lund, Sweden
| | - Daniel Svensson
- Department of Experimental Medical Science, Lund University, Lund, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Solna, Sweden
| | - Bengt-Olof Nilsson
- Department of Experimental Medical Science, Lund University, Lund, Sweden.
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9
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Sheng Y, Wen L, Zheng X, Li M, Wang D, Chen S, Li R, Tang L, Zhou F. CYP2S1 might regulate proliferation and immune response of keratinocyte in psoriasis. Epigenetics 2020; 16:618-628. [PMID: 32924783 DOI: 10.1080/15592294.2020.1814486] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Psoriasis is an autoimmune skin disorder influenced by genetic, epigenetic and environmental factors. We previously found CYP2S1 intragenic DNA methylation cg19430423 site strongly hypomethylated in psoriatic skin tissues. In this study, we performed methylation loci fine-mapping to search the top signals in the entire CYP2S1 gene region, and further carried out gene expression assay, cell proliferation, apoptosis, differentiation and migration in CYP2S1 overexpressed (CYP2S1over) and silenced (siRNA) human keratinocytes. Target bisulphite conversion sequencing revealed cg19430423 and nearby two loci were the top differentially methylated loci. These three loci located within active enhancer region marked by H3K4Me1 and H3K27AC peaks. Cg19430423 might not bind with ATF1 directly. CYP2S1over repressed NHEK cell proliferation, but have no confirmed evidence on affecting migration, apoptosis and differentiation. Real-time PCR showed that CYP2S1 inhibited expression of IL1β, IL8, IL33, IL36, LL37, CXCL10 and CCL20 gene. In summary, CYP2S1 might inhibit keratinocyte proliferation, and modulate immune response through IL-8, IL-33, IL-36, CXCL-10, CCL20, thus contribute to the development of psoriasis.
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Affiliation(s)
- Yujun Sheng
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China
| | - Leilei Wen
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China
| | - Xiaodong Zheng
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China
| | - Mengqing Li
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China
| | - Dan Wang
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China
| | - Sixian Chen
- The First Clinical Medical College, Anhui Medical University, Hefei, China
| | - Ran Li
- The First Clinical Medical College, Anhui Medical University, Hefei, China
| | - Lili Tang
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China
| | - Fusheng Zhou
- Department of Dermatology, the First Affiliated Hospital, Anhui Medical University, Hefei, China.,Institute of Dermatology, Anhui Medical University, Hefei, China.,Key Laboratory of Dermatology, Anhui Medical University, Ministry of Education, Hefei, China.,State Key Laboratory Incubation Base of Dermatology, Anhui Medical University, Hefei, China.,Inflammation and Immune Mediated Diseases Laboratory, Anhui Province, Hefei, China.,Department of Biological Chemistry, School of Medicine, University of California, Irvine, CA, USA
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10
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Alford MA, Baquir B, Santana FL, Haney EF, Hancock REW. Cathelicidin Host Defense Peptides and Inflammatory Signaling: Striking a Balance. Front Microbiol 2020; 11:1902. [PMID: 32982998 PMCID: PMC7481365 DOI: 10.3389/fmicb.2020.01902] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 07/20/2020] [Indexed: 12/28/2022] Open
Abstract
Host-defense peptides (HDPs) are vital components of innate immunity in all vertebrates. While their antibacterial activity toward bacterial cells was the original focus for research, their ability to modulate immune and inflammatory processes has emerged as one of their major functions in the host and as a promising approach from which to develop novel therapeutics targeting inflammation and innate immunity. In this review, with particular emphasis on the cathelicidin family of peptides, the roles of natural HDPs are examined in managing immune activation, cellular recruitment, cytokine responses, and inflammation in response to infection, as well as their contribution(s) to various inflammatory disorders and autoimmune diseases. Furthermore, we discuss current efforts to develop synthetic HDPs as therapeutics aimed at restoring balance to immune responses that are dysregulated and contribute to disease pathologies.
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Affiliation(s)
- Morgan A. Alford
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, BC, Canada
| | - Beverlie Baquir
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, BC, Canada
| | - Felix L. Santana
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, BC, Canada
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
| | - Evan F. Haney
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, BC, Canada
| | - Robert E. W. Hancock
- Centre for Microbial Diseases and Immunity Research, University of British Columbia, Vancouver, BC, Canada
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11
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Scheenstra MR, van Harten RM, Veldhuizen EJA, Haagsman HP, Coorens M. Cathelicidins Modulate TLR-Activation and Inflammation. Front Immunol 2020; 11:1137. [PMID: 32582207 PMCID: PMC7296178 DOI: 10.3389/fimmu.2020.01137] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Accepted: 05/11/2020] [Indexed: 12/30/2022] Open
Abstract
Cathelicidins are short cationic peptides that are part of the innate immune system. At first, these peptides were studied mostly for their direct antimicrobial killing capacity, but nowadays they are more and more appreciated for their immunomodulatory functions. In this review, we will provide a comprehensive overview of the various effects cathelicidins have on the detection of damage- and microbe-associated molecular patterns, with a special focus on their effects on Toll-like receptor (TLR) activation. We review the available literature based on TLR ligand types, which can roughly be divided into lipidic ligands, such as LPS and lipoproteins, and nucleic-acid ligands, such as RNA and DNA. For both ligand types, we describe how direct cathelicidin-ligand interactions influence TLR activation, by for instance altering ligand stability, cellular uptake and receptor interaction. In addition, we will review the more indirect mechanisms by which cathelicidins affect downstream TLR-signaling. To place all this information in a broader context, we discuss how these cathelicidin-mediated effects can have an impact on how the host responds to infectious organisms as well as how these effects play a role in the exacerbation of inflammation in auto-immune diseases. Finally, we discuss how these immunomodulatory activities can be exploited in vaccine development and cancer therapies.
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Affiliation(s)
- Maaike R Scheenstra
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, Netherlands
| | - Roel M van Harten
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, Netherlands
| | - Edwin J A Veldhuizen
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, Netherlands
| | - Henk P Haagsman
- Division of Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Utrecht University, Utrecht, Netherlands
| | - Maarten Coorens
- Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institute, Stockholm, Sweden.,Department of Clinical Microbiology, Karolinska University Laboratory, Stockholm, Sweden
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12
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Human host defense peptide LL-37 facilitates double-stranded RNA pro-inflammatory signaling through up-regulation of TLR3 expression in vascular smooth muscle cells. Inflamm Res 2020; 69:579-588. [PMID: 32221618 PMCID: PMC7200649 DOI: 10.1007/s00011-020-01340-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 02/28/2020] [Accepted: 03/16/2020] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE The importance of human host defense peptide LL-37 in vascular innate immunity is not understood. Here, we assess the impact of LL-37 on double-stranded RNA (dsRNA) signaling in human vascular smooth muscle cells. MATERIALS AND METHODS Cellular import of LL-37 and synthetic dsRNA (poly I:C) were investigated by immunocytochemistry and fluorescence imaging. Transcript and protein expression were determined by qPCR, ELISA and Western blot. Knockdown of TLR3 was performed by siRNA. RESULTS LL-37 was rapidly internalized, suggesting that it has intracellular actions. Co-stimulation with poly I:C and LL-37 enhanced pro-inflammatory IL-6 and MCP-1 transcripts several fold compared to treatment with poly I:C or LL-37 alone. Poly I:C increased IL-6 and MCP-1 protein production, and this effect was potentiated by LL-37. LL-37-induced stimulation of poly I:C signaling was not associated with enhanced import of poly I:C. Treatment with poly I:C and LL-37 in combination increased expression of dsRNA receptor TLR3 compared to stimulation with poly I:C or LL-37 alone. In TLR3 knockdown cells, treatment with poly I:C and LL-37 in combination had no effect on IL-6 and MCP-1 expression, showing loss of function. CONCLUSIONS LL-37 potentiates dsRNA-induced cytokine production through up-regulation of TLR3 expression representing a novel pro-inflammatory mechanism.
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Shahid M, Cavalcante PA, Knight CG, Barkema HW, Han B, Gao J, Cobo ER. Murine and Human Cathelicidins Contribute Differently to Hallmarks of Mastitis Induced by Pathogenic Prototheca bovis Algae. Front Cell Infect Microbiol 2020; 10:31. [PMID: 32117805 PMCID: PMC7025567 DOI: 10.3389/fcimb.2020.00031] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 01/17/2020] [Indexed: 12/12/2022] Open
Abstract
Prototheca bovis (formerly P. zopfii genotype-II) is an opportunistic, achlorophyllous alga that causes mastitis in cows and skin disease in cats and dogs, as well as cutaneous lesions in both immunocompetent and immunosuppressed humans. Antifungal medications are commonly ineffective. This study aimed to investigate innate immune responses contributed by cathelicidins to P. bovis in the mammary gland using a mastitis model in mice deficient in the sole murine cathelicidin (Camp). We determined P. bovis caused acute mastitis in mice and induced Camp gene transcription. Whereas, Camp-/- and Camp+/+ littermates had similar local algae burden, Camp+/+ mice produced more pro-inflammatory cytokines, TNF-α, and Cxcl-1. Likewise, Camp+/+ bone marrow-derived macrophages were more responsive to P. bovis, producing more TNF-α and Cxcl-1. Human cathelicidin (LL-37) exhibited a different effect against P. bovis; it had direct algicidal activity against P. bovis and lowered TNF-α, Cxcl-1, and IL-1β production in both cultured murine macrophages and mammary epithelial cells exposed to the pathogenic algae. In conclusion, cathelicidins were involved in protothecosis pathogenesis, with unique roles among the diverse peptide family. Whereas, endogenous cathelicidin (Camp) was key in mammary gland innate defense against P. bovis, human LL-37 had algicidal and immunomodulatory functions.
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Affiliation(s)
- Muhammad Shahid
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Paloma Araujo Cavalcante
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Cameron G. Knight
- Department of Veterinary Clinical and Diagnostic Sciences, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Herman W. Barkema
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
| | - Bo Han
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Jian Gao
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Eduardo R. Cobo
- Department of Production Animal Health, Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada
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Head BM, Mao R, Keynan Y, Rueda ZV. Inflammatory mediators and lung abnormalities in HIV: A systematic review. PLoS One 2019; 14:e0226347. [PMID: 31830103 PMCID: PMC6907827 DOI: 10.1371/journal.pone.0226347] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 11/25/2019] [Indexed: 12/16/2022] Open
Abstract
HIV and pneumonia infections have both been shown to negatively impact lung function. However, evidence of the role of inflammation on lung dysfunction in HIV and pneumonia co-infected individuals remains limited. We aimed to systematically review the association of inflammatory markers and lung abnormalities in HIV and pneumonia co-infected individuals. This systematic review was registered with the International Prospective Register of Systematic Reviews on August 15, 2017 (registration number CRD42017069254) and used 4 databases (Cochrane Central Register of Controlled Trials, PubMed Central, Clinical Trials.gov and Google Scholar). All clinical trial, observational, and comparative studies targeting adult (> 18 years old) populations with HIV, pneumonia, or both, that report on immune response (cytokine, chemokine, or biomarker), and lung abnormality as an outcome were eligible. Data selection, risk of bias and extraction were performed independently by 2 blinded reviewers. Due to heterogeneity among the articles, a qualitative synthesis was performed. Our search strategy identified 4454 articles of which, 7 met our inclusion criteria. All of the studies investigated the ability of circulating biomarkers to predict lung damage in HIV. None of the articles included patients with both HIV and pneumonia, nor pneumonia alone. Markers of inflammation (IL-6, TNF-α, CRP), innate defense (cathelicidin), monocyte and macrophage activation (sCD14, sCD163 and, IL-2sRα), endothelial dysfunction (ET-1) and general immune health (CD4/CD8 ratio) were associated with lung abnormalities in HIV. This review highlights the lack of available information regarding the impact of inflammatory mediators on lung function in HIV and pneumonia populations, therefore opportunities to prevent lung damage with available anti-inflammatory treatment or to investigate new ones still remain.
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Affiliation(s)
- Breanne M. Head
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Ruochen Mao
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Yoav Keynan
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Zulma Vanessa Rueda
- Department of Medical Microbiology and Infectious Diseases, University of Manitoba, Winnipeg, Manitoba, Canada
- Facultad de Medicina, Universidad Pontificia Bolivariana, Medellín, Antioquia, Colombia
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15
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Aidoukovitch A, Anders E, Dahl S, Nebel D, Svensson D, Nilsson BO. The host defense peptide LL-37 is internalized by human periodontal ligament cells and prevents LPS-induced MCP-1 production. J Periodontal Res 2019; 54:662-670. [PMID: 31095741 DOI: 10.1111/jre.12667] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 03/15/2019] [Accepted: 04/20/2019] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The human host defense peptide LL-37 both shows antimicrobial effects and modulates host cell properties. Here, we assess the effects of synthesized LL-37 on lipopolysaccharide (LPS)-induced inflammation in human periodontal ligament (PDL) cells and investigates underlying mechanisms. BACKGROUND LL-37 has been detected in the periodontal tissues, but its functional importance for PDL cell innate immune responses is not known. METHODS Human PDL cells were obtained from premolars extracted on orthodontic indications. Cellular pro-inflammatory monocyte chemoattractant protein-1 (MCP-1) mRNA expression was determined using quantitative real-time RT-PCR. MCP-1 protein production was assessed by western blot and ELISA. Internalization of LL-37 by PDL cells was visualized by immunocytochemistry. Nuclear factor kappa-light-chain-enhancer of activated B-cell (NF-κB) activity was assessed by western blot of phosphorylated p65, phosphorylated p105, and IκBα proteins. Binding of LL-37 to PDL cell DNA was determined by isolation and purification of DNA and dot blot for LL-37 immunoreactivity. RESULTS Treatment with LL-37 (1 µmol/L) for 24 hours prevented LPS-induced stimulation of MCP-1 expression analyzed both on transcript and on protein levels. Stimulation with LL-37 (1 µmol/L) for 24 hours had no effect on toll-like receptor (TLR)2 and TLR4 transcript expression, suggesting that LL-37 acts downstream of the TLRs. Preincubation with LL-37 for 60 minutes followed by stimulation with LPS for 24 hours in the absence of LL-37 completely prevented LPS-evoked MCP-1 transcript expression, implying that LL-37 acts intracellularly and not via binding and neutralization of LPS. In PDL cells stimulated with LL-37 for 60 minutes, the peptide was internalized as demonstrated by immunocytochemistry, suggesting an intracellular mechanism of action. LL-37 immunoreactivity was observed both in the cytosol and in the nucleus. Downregulation of LPS-induced MCP-1 by LL-37 was not mediated by reduction in NF-κB activity as shown by unaltered expression of phosphorylated p65, phosphorylated p105, and IκBα NF-κB proteins in the presence of LL-37. Immunoreactivity for LL-37 was observed in PDL cell DNA treated with but not without 0.1 and 1 µmol/L LL-37 for 60 minutes in vitro. CONCLUSION LL-37 abolishes LPS-induced MCP-1 production in human PDL cells through an intracellular, NF-κB-independent mechanism which probably involves direct interaction between LL-37 and DNA.
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Affiliation(s)
- Alexandra Aidoukovitch
- Department of Experimental Medical Science, Lund University, Lund, Sweden.,Folktandvården Skåne, Lund, Sweden
| | - Emma Anders
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Sara Dahl
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Daniel Nebel
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Daniel Svensson
- Department of Experimental Medical Science, Lund University, Lund, Sweden.,Department of Women's and Children's Health, Karolinska Institute, Solna, Sweden
| | - Bengt-Olof Nilsson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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16
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de Miguel Catalina A, Forbrig E, Kozuch J, Nehls C, Paulowski L, Gutsmann T, Hildebrandt P, Mroginski MA. The C-Terminal VPRTES Tail of LL-37 Influences the Mode of Attachment to a Lipid Bilayer and Antimicrobial Activity. Biochemistry 2019; 58:2447-2462. [DOI: 10.1021/acs.biochem.8b01297] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Enrico Forbrig
- Department of Physical Chemistry, Institut für Chemie, Technische Universität Berlin, Berlin 10623, Germany
| | - Jacek Kozuch
- Division of Chemistry, Stanford University, Stanford, Californa 94305, United States
| | - Christian Nehls
- Biophysics Department, Forschungszentrum Borstel, Leibniz Lungenzentrum, Borstel 23845, Germany
| | - Laura Paulowski
- Biophysics Department, Forschungszentrum Borstel, Leibniz Lungenzentrum, Borstel 23845, Germany
| | - Thomas Gutsmann
- Biophysics Department, Forschungszentrum Borstel, Leibniz Lungenzentrum, Borstel 23845, Germany
| | - Peter Hildebrandt
- Department of Physical Chemistry, Institut für Chemie, Technische Universität Berlin, Berlin 10623, Germany
| | - Maria Andrea Mroginski
- Department of Physical Chemistry, Institut für Chemie, Technische Universität Berlin, Berlin 10623, Germany
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17
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Sharma P, Sharma N, Mishra P, Joseph J, Mishra DK, Garg P, Roy S. Differential Expression of Antimicrobial Peptides in Streptococcus pneumoniae Keratitis and STAT3-Dependent Expression of LL-37 by Streptococcus pneumoniae in Human Corneal Epithelial Cells. Pathogens 2019; 8:pathogens8010031. [PMID: 30845777 PMCID: PMC6470555 DOI: 10.3390/pathogens8010031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 12/15/2022] Open
Abstract
Streptococcus pneumoniae is the leading cause of bacterial keratitis in the developing world with a growing trend of acquiring resistance against various antibiotics. In the current study, we determined the expression of different antimicrobial peptides (AMPs) in response to S. pneumoniae in patients, as well as in primary and immortalized human corneal epithelial cells. We further focused on LL-37 and determined its expression in human cornea infected with S. pneumoniae and studied the killing ability of LL-37 against S. pneumoniae. The expression of AMPs was determined by quantitative PCR and the phosphorylation of signaling proteins was evaluated by immunoblot analysis. LL-37 expression was also determined by immunofluorescence and Western blot method and the killing ability of LL-37 against S. pneumoniae was determined by colony-forming units. Differential expression of antimicrobial peptides was observed in patients with S. pneumoniae keratitis. Although S. pneumoniae induced expression of the AMPs in human corneal epithelial cells (HCEC), it did not induce AMP expression in U937, a human monocyte cell line. S. pneumoniae also caused activation of nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB)and mitogen activated protein kinase (MAPK) pathways in corneal epithelial cells. LL-37 was found to be effective against both laboratory and clinical strains of S. pneumoniae. LL-37 induction by S. pneumoniae in human corneal epithelial cells was mediated by signal transducer and activator of transcription 3 (STAT3) activation, and inhibition of STAT3 activation significantly reduced LL-37 expression. Our study determines an extensive profile of AMPs expressed in the human cornea during S. pneumoniae infection, and suggests the potential of LL-37 to be developed as an alternative therapeutic intervention to fight increasing antibiotic resistance among bacteria.
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Affiliation(s)
- Prerana Sharma
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
- Department of Animal Sciences, University of Hyderabad, Hyderabad 500046, India.
| | - Natalia Sharma
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Priyasha Mishra
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Joveeta Joseph
- Jhaveri Microbiology Centre, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Dilip K Mishra
- Pathology Department, LV Prasad Eye Institute, Hyderabad 500034, India.
| | - Prashant Garg
- Tej Kohli Cornea Institute, Hyderabad 500034, India.
| | - Sanhita Roy
- Prof. Brien Holden Eye Research Center, LV Prasad Eye Institute, Hyderabad 500034, India.
- Tej Kohli Cornea Institute, Hyderabad 500034, India.
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18
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Shi N, Cai S, Gao J, Qiao X, Yang H, Wang Y, Yu H. Roles of polymorphic cathelicidins in innate immunity of soft-shell turtle, Pelodiscus sinensis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2019; 92:179-192. [PMID: 30452933 DOI: 10.1016/j.dci.2018.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Revised: 11/13/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
Cathelicidins are a class of gene-encoded immune effectors in vertebrate innate immune system. Though being extensively studied in mammals, little is known about the roles of cathelicidins in turtles, the water-dwelling vertebrates in the order Testudines. In the present study, six novel cathelicidins (Ps-CATH1-6) with different tissue and inducible expression patterns were characterized from the turtle of economic importance, Chinese soft-shell turtle (Pelodiscus sinensis). Although the structures of Ps-CATH1-6 precursors were identical with most of the other known cathelicidins, the mature peptides of Ps-CATH1-6 showed low sequence similarity with the other cathelicidins. Functional studies indicated that some of them either directly kill pathogens via inducing the permeabilization in bacterial membrane (Ps-CATH4, 6), or boost infection-resolving immunity by selectively inhibiting pro-inflammatory responses (Ps-CATH2, 4, 6) through MAPKs and NF-κB pathways. Ps-CATH2, 4, and 6, which assume the hallmark amphipathic α-helical conformations as most of the other host defense peptides, exhibit evident in vivo protection by significantly reducing the bacterial loads in bacterial infected turtles. Collectively, the discovery of novel Ps-CATHs with pleiotropic structures and functions helps elucidating the roles of cathelicidins in the Chinese softshell turtle innate immunity, and better understanding the survival strategy of Chinese softshell turtle in harsh habitat.
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Affiliation(s)
- Nannan Shi
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Shasha Cai
- School of Medical Engineering, Jining Medical University, Jining, Shandong, 272000, China
| | - Jiuxiang Gao
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Xue Qiao
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Huaixin Yang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning, 116024, China
| | - Yipeng Wang
- Department of Pharmaceutical Sciences, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China.
| | - Haining Yu
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian, Liaoning, 116024, China.
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19
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Dahl S, Anders E, Gidlöf O, Svensson D, Nilsson BO. The host defense peptide LL-37 triggers release of nucleic acids from human mast cells. Peptides 2018; 109:39-45. [PMID: 30308233 DOI: 10.1016/j.peptides.2018.10.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 09/28/2018] [Accepted: 10/05/2018] [Indexed: 12/23/2022]
Abstract
The human host defense peptide LL-37 possesses antimicrobial activity but also affects host cell function and viability. Mast cells are involved in innate immunity but no data have been presented on effects of LL-37 on human mast cell viability and export of nucleic acids. Here, we demonstrated by immunofluorescence microscopy that synthesized LL-37 was internalized by human LAD2 mast cells and detected both in cytoplasm and nucleus. Treatment with high (4 and 10 μM) but not low (1 μM) concentrations of LL-37 for 4 h reduced cell viability assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Stimulation with 10 μM LL-37 for 4 h enhanced export of nucleic acids, total protein and lactate dehydrogenase (LDH), suggesting that both nuclear and plasma membranes are permeabilized by LL-37. Although LL-37 triggered release of nucleic acids, no extracellular trap-like structures were observed by laser scanning confocal microscopy of cells incubated with the plasma membrane impermeable nucleic acid fluorophore SYTOX-Green, indicating that LL-37 promotes export of nucleic acids but not formation of extracellular traps. On the other hand, phorbol-12-myristate-13-acetate (PMA), which is a well-known inducer of extracellular traps, stimulated export of nucleic acids and also formation of extracellular trap-like structures. However, PMA had no effect on export of either total protein or LDH. Hence, LL-37 and PMA seem to stimulate export of nucleic acids from LAD2 mast cells through different pathways. In conclusion, we demonstrate that LL-37 triggers release of nucleic acids from human mast cells but not the formation of extracellular trap-like structures.
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Affiliation(s)
- Sara Dahl
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Emma Anders
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Olof Gidlöf
- Department of Cardiology, Clinical Sciences, Lund University, Skåne University Hospital, Lund, Sweden
| | - Daniel Svensson
- Department of Experimental Medical Science, Lund University, Lund, Sweden; Department of Women's and Children's Health, Karolinska Institute, Solna, Sweden
| | - Bengt-Olof Nilsson
- Department of Experimental Medical Science, Lund University, Lund, Sweden.
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20
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Lee MW, Lee EY, Wong GCL. What Can Pleiotropic Proteins in Innate Immunity Teach Us about Bioconjugation and Molecular Design? Bioconjug Chem 2018; 29:2127-2139. [PMID: 29771496 DOI: 10.1021/acs.bioconjchem.8b00176] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A common bioengineering strategy to add function to a given molecule is by conjugation of a new moiety onto that molecule. Adding multiple functions in this way becomes increasingly challenging and leads to composite molecules with larger molecular weights. In this review, we attempt to gain a new perspective by looking at this problem in reverse, by examining nature's strategies of multiplexing different functions into the same pleiotropic molecule using emerging analysis techniques such as machine learning. We concentrate on examples from the innate immune system, which employs a finite repertoire of molecules for a broad range of tasks. An improved understanding of how diverse functions are multiplexed into a single molecule can inspire new approaches for the deterministic design of multifunctional molecules.
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21
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Svensson D, Aidoukovitch A, Anders E, Agerberth B, Andersson F, Ekblad E, Ericson D, Nebel D, Voss U, Nilsson BO. The host defense peptide LL-37 is detected in human parotid and submandibular/sublingual saliva and expressed in glandular neutrophils. Eur J Oral Sci 2018; 126:93-100. [PMID: 29424090 DOI: 10.1111/eos.12407] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The human host defense peptide, LL-37, is an important player in the first line of defense against invading microorganisms. LL-37 and its precursor, hCAP18, have been detected in unstimulated whole saliva but no reports showing hCAP18/LL-37 in isolated, parotid, and/or submandibular/sublingual saliva have been presented. Here, we measured the levels of hCAP18/LL-37 in human parotid and submandibular/sublingual saliva and investigated the expression of hCAP18/LL-37 in parotid and submandibular gland tissue. Parotid and submandibular/sublingual saliva was collected from healthy volunteers, and the levels of hCAP18/LL-37 in saliva were analyzed by dot blot, ELISA, and western blotting. Cellular expression of hCAP18/LL-37 in human parotid and submandibular glands was investigated by immunohistochemistry. Immunoreactivity for hCAP18/LL-37 was detected in both parotid and submandibular/sublingual saliva of all individuals. The concentration of hCAP18/LL-37 was similar in parotid and submandibular/sublingual saliva, and was determined by densitometric scanning of each dot and normalization to the total protein concentration of each sample, and by ELISA. Double immunohistochemistry revealed that intravascular neutrophils of both parotid and submandibular glands express hCAP18/LL-37. For the first time, we demonstrate hCAP18/LL-37 in isolated human parotid and submandibular/sublingual saliva and expression of hCAP18/LL-37 in glandular intravascular neutrophils, indicating that neutrophils of the major salivary glands contribute to the LL-37 content of whole saliva.
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Affiliation(s)
- Daniel Svensson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Alexandra Aidoukovitch
- Department of Experimental Medical Science, Lund University, Lund, Sweden.,Folktandvården Skåne, Malmö, Sweden
| | - Emma Anders
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Birgitta Agerberth
- Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institute, Karolinska University Hospital, Huddinge, Sweden
| | - Fredrik Andersson
- Regional Laboratories Region Skåne, Department of Pathology, Skåne University Hospital Lund, Lund, Sweden
| | - Eva Ekblad
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Dan Ericson
- Department of Cariology, Faculty of Odontology, Malmö University, Malmö, Sweden
| | - Daniel Nebel
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Ulrikke Voss
- Department of Experimental Medical Science, Lund University, Lund, Sweden
| | - Bengt-Olof Nilsson
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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22
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Coorens M, Schneider VAF, de Groot AM, van Dijk A, Meijerink M, Wells JM, Scheenstra MR, Veldhuizen EJA, Haagsman HP. Cathelicidins Inhibit Escherichia coli-Induced TLR2 and TLR4 Activation in a Viability-Dependent Manner. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2017; 199:1418-1428. [PMID: 28710255 PMCID: PMC5544931 DOI: 10.4049/jimmunol.1602164] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 06/09/2017] [Indexed: 11/19/2022]
Abstract
Activation of the immune system needs to be tightly regulated to provide protection against infections and, at the same time, to prevent excessive inflammation to limit collateral damage to the host. This tight regulation includes regulating the activation of TLRs, which are key players in the recognition of invading microbes. A group of short cationic antimicrobial peptides, called cathelicidins, have previously been shown to modulate TLR activation by synthetic or purified TLR ligands and may play an important role in the regulation of inflammation during infections. However, little is known about how these cathelicidins affect TLR activation in the context of complete and viable bacteria. In this article, we show that chicken cathelicidin-2 kills Escherichia coli in an immunogenically silent fashion. Our results show that chicken cathelicidin-2 kills E. coli by permeabilizing the bacterial inner membrane and subsequently binds the outer membrane-derived lipoproteins and LPS to inhibit TLR2 and TLR4 activation, respectively. In addition, other cathelicidins, including human, mouse, pig, and dog cathelicidins, which lack antimicrobial activity under cell culture conditions, only inhibit macrophage activation by nonviable E. coli In total, this study shows that cathelicidins do not affect immune activation by viable bacteria and only inhibit inflammation when bacterial viability is lost. Therefore, cathelicidins provide a novel mechanism by which the immune system can discriminate between viable and nonviable Gram-negative bacteria to tune the immune response, thereby limiting collateral damage to the host and the risk for sepsis.
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Affiliation(s)
- Maarten Coorens
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands
| | - Viktoria A F Schneider
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands
| | - A Marit de Groot
- Division of Immunology, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands; and
| | - Albert van Dijk
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands
| | - Marjolein Meijerink
- Host Microbe Interactomics Group, Department of Animal Sciences, Wageningen University, 6700 AH Wageningen, the Netherlands
| | - Jerry M Wells
- Host Microbe Interactomics Group, Department of Animal Sciences, Wageningen University, 6700 AH Wageningen, the Netherlands
| | - Maaike R Scheenstra
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands
| | - Edwin J A Veldhuizen
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands
| | - Henk P Haagsman
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, the Netherlands;
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23
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Pradhan B, Guha D, Murmu KC, Sur A, Ray P, Das D, Aich P. Comparative efficacy analysis of anti-microbial peptides, LL-37 and indolicidin upon conjugation with CNT, in human monocytes. J Nanobiotechnology 2017; 15:44. [PMID: 28606090 PMCID: PMC5469186 DOI: 10.1186/s12951-017-0278-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 06/02/2017] [Indexed: 01/23/2023] Open
Abstract
BACKGROUND Antimicrobial peptides (AMPs) have the potential to serve as an alternative to antibiotic. AMPs usually exert bactericidal activity via direct killing of microbial pathogens. Reports have proposed that by harnessing innate immune activation, AMPs can regulate pathogen invasion and may control infection. It has been reported that AMPs could be utilized to activate the innate mucosal immune response in order to eliminate pathogenic infections. This way of controlling pathogen infection, by activating host immunity, confers the potential to the select AMPs to alleviate the problem of antibiotic resistance. Among various AMPs tested LL-37 and indolicidin, showed promise to be potential candidates for eliciting enhanced host innate immune responses. LL-37 and indolicidin had exhibited substantial innate immune activation in both human and murine macrophages. Dosage for each of the AMPs, however, was high with adverse side effects. RESULTS In this study, we reported that upon conjugation with carbon nanotubes (CNT), each AMP remained biologically functional at a concentration that was 1000-fold less than the dosage required for free AMP to remain active in the cells. CONCLUSIONS Current study also revealed that while indolicidin induced signalling events mediated through the TNFRSF1A pathway in THP1 cells, followed by activation of NFκB and c-JUN pathways, treatment of cells with LL-37 induced signalling events by activating IL1R, with subsequent activation of NFκB and NFAT2. Thp1 cells, primed with CNT conjugated LL-37 or indolicidin, are protected against Salmonella typhimurium infection at 16 h post challenge.
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Affiliation(s)
- Biswaranjan Pradhan
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India
| | - Dipanjan Guha
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India
| | - Krushna Chandra Murmu
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India
| | - Abhinav Sur
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India
| | - Pratikshya Ray
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India
| | - Debashmita Das
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India
| | - Palok Aich
- School of Biological Sciences, National Institute of Science Education and Research (NISER), HBNI, P.O. Bhimpur-Padanpur, Khurdha, Jatni, Odisha, 752050, India.
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Svensson D, Nebel D, Voss U, Ekblad E, Nilsson BO. Vitamin D-induced up-regulation of human keratinocyte cathelicidin anti-microbial peptide expression involves retinoid X receptor α. Cell Tissue Res 2016; 366:353-362. [PMID: 27357804 DOI: 10.1007/s00441-016-2449-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 05/20/2016] [Indexed: 01/07/2023]
Abstract
The biologically active form of vitamin D, 1α,25-dihydroxyvitamin D3 (1,25D3), has been reported to positively regulate the human cathelicidin anti-microbial peptide (CAMP) gene coding for LL-37, but the mechanisms are not completely understood. We have determined the expression of CAMP, vitamin D receptor (VDR), and the retinoid X receptor (RXR) isoforms in human skin and gingival tissue biopsies and investigated the signaling pathways involved in 1,25D3-induced upregulation of CAMP. Human skin and gingival biopsies exhibited few VDR-immunoreactive cells within the stratum basale, whereas rat colon enterocytes (positive control) possessed abundant VDR immunoreactivity. Nuclear VDR immunoreactivity was demonstrated in human skin keratinocytes (HaCaT cells). Gene analysis revealed that human skin biopsies expressed higher levels of both CAMP and RXRα mRNA than human gingival biopsies, whereas VDR and RXRβ transcript levels were similar in skin and gingiva. In HaCaT cells, treatment with 1,25D3 (5 nM and 1 μM) for 4 and 24 h up-regulated CAMP mRNA several fold, and treatment with 1,25D3 for 24 h increased protein expression of the pro-form of LL-37 (hCAP-18) by about 13 times. The 1,25D3-evoked stimulation of HaCaT CAMP expression was associated with attenuated VDR mRNA and protein expression. Treatment with RXRα short interfering RNA reversed the 1,25D3-induced CAMP expression in HaCaT cells, showing that RXRα is involved in the up-regulation of CAMP by 1,25D3. We conclude that the 1,25D3-evoked stimulation of CAMP expression in human skin keratinocytes is dependent on RXRα but is not associated with the up-regulation of VDR expression.
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Affiliation(s)
- Daniel Svensson
- Department of Experimental Medical Science, Lund University, BMC D12, SE-221 84, Lund, Sweden
| | - Daniel Nebel
- Department of Experimental Medical Science, Lund University, BMC D12, SE-221 84, Lund, Sweden
| | - Ulrikke Voss
- Department of Experimental Medical Science, Lund University, BMC D12, SE-221 84, Lund, Sweden
| | - Eva Ekblad
- Department of Experimental Medical Science, Lund University, BMC D12, SE-221 84, Lund, Sweden
| | - Bengt-Olof Nilsson
- Department of Experimental Medical Science, Lund University, BMC D12, SE-221 84, Lund, Sweden.
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Vitamin D3 modulates the innate immune response through regulation of the hCAP-18/LL-37 gene expression and cytokine production. Inflamm Res 2015; 65:25-32. [DOI: 10.1007/s00011-015-0884-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Revised: 09/11/2015] [Accepted: 09/24/2015] [Indexed: 01/05/2023] Open
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Xu Y, Zhang T, Xu Q, Han Z, Liang S, Shao Y, Ma D, Liu S. Differential modulation of avian β-defensin and Toll-like receptor expression in chickens infected with infectious bronchitis virus. Appl Microbiol Biotechnol 2015; 99:9011-24. [PMID: 26142390 PMCID: PMC7080159 DOI: 10.1007/s00253-015-6786-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Revised: 06/14/2015] [Accepted: 06/19/2015] [Indexed: 12/20/2022]
Abstract
The host innate immune response either clears invading viruses or allows the adaptive immune system to establish an effective antiviral response. In this study, both pathogenic (passage 3, P3) and attenuated (P110) infectious bronchitis virus (IBV) strains were used to study the immune responses of chicken to IBV infection. Expression of avian β-defensins (AvBDs) and Toll-like receptors (TLRs) in 16 tissues of chicken were compared at 7 days PI. The results showed that P3 infection upregulated the expression of AvBDs, including AvBD2, 4, 5, 6, 9, and 12, while P110 infection downregulated the expression of AvBDs, including AvBD3, 4, 5, 6, and 9 in most tissues. Meanwhile, the expression level of several TLRs showed a general trend of upregulation in the tissues of P3-infected chickens, while they were downregulated in the tissues of P110-infected chickens. The result suggested that compared with the P110 strain, the P3 strain induced a more pronounced host innate immune response. Furthermore, we observed that recombinant AvBDs (including 2, 6, and 12) demonstrated obvious anti-viral activity against IBV in vitro. Our findings contribute to the proposal that IBV infection induces an increase in the messenger RNA (mRNA) expression of some AvBDs and TLRs, which suggests that AvBDs may play significant roles in the resistance of chickens to IBV replication.
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Affiliation(s)
- Yang Xu
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Tingting Zhang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Qianqian Xu
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Zongxi Han
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001, People's Republic of China
| | - Shuling Liang
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Yuhao Shao
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001, People's Republic of China
| | - Deying Ma
- College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Shengwang Liu
- Division of Avian Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001, People's Republic of China.
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Bacterial flagellin induces IL-6 expression in human basophils. Mol Immunol 2015; 65:168-76. [PMID: 25660969 DOI: 10.1016/j.molimm.2015.01.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/16/2015] [Accepted: 01/19/2015] [Indexed: 01/13/2023]
Abstract
Binding of allergen to IgE on basophils positively affects allergic inflammation by releasing inflammatory mediators. Recently, basophils were shown to express pattern-recognition receptors, such as toll-like receptors (TLRs), for recognizing microbe-associated molecular patterns (MAMPs) that are independent of allergen-IgE binding. In this study, we investigated whether MAMP alone can induce IL-6 production in a human basophil cell line, KU812. Stimulation with flagellin in the absence of allergen-IgE association induced IL-6 expression in KU812 cells, while stimulation with lipoteichoic acid, peptidoglycan, or poly I:C did not under the same condition. Flagellin-induced IL-6 expression was also observed in human primary basophils. Flow cytometric analysis showed that KU812 cells expressed flagellin-recognizing TLR5 both on the cell surface and in the cytoplasm while TLR2 and TLR3 were observed only in the cytoplasm. We further demonstrated that although flagellin augmented the phosphorylation of mitogen-activated protein kinases including p38 kinase, ERK, and JNK, flagellin-induced IL-6 production was attenuated by inhibitors for p38 kinase and ERK, but not by JNK inhibitors. In addition, flagellin enhanced phosphorylation of signaling molecules including CREB, PKCδ, and AKT. The inhibitors for PKA and PKC also showed inhibitory effects. Interestingly, flagellin-induced IL-6 production was further enhanced by pretreatment with inhibitors for PI3K, implying that PI3K negatively affects the flagellin-induced IL-6 production. Furthermore, DNA binding activities of NF-κB, AP-1, and CREB, which play pivotal roles in the induction of IL-6 gene expression, were increased by flagellin. These results suggest that flagellin alone is sufficient to induce IL-6 gene expression via TLR5 signaling pathways in human basophils.
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Lim R, Barker G, Lappas M. Human cathelicidin antimicrobial protein 18 (hCAP18/LL-37) is increased in foetal membranes and myometrium after spontaneous labour and delivery. J Reprod Immunol 2014; 107:31-42. [PMID: 25435436 DOI: 10.1016/j.jri.2014.10.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 10/15/2014] [Accepted: 10/17/2014] [Indexed: 01/01/2023]
Abstract
Infection and/or inflammation are most commonly associated with preterm birth. Studies have shown that antimicrobial peptides can modulate the inflammatory response in non-gestational tissues; the human cathelicidin hCAP18 (and its active component LL-37) has such anti-microbial and immunomodulatory properties. The aim of this study was to determine the effect of human labour on hCAP18 expression in foetal membranes and myometrium, and to determine the effect of the synthetic LL-37 peptide on pro-inflammatory and pro-labour mediators in foetal membranes and myometrium. The localisation and expression of hCAP18 in non-labouring and labouring tissues was determined by immunohistochemistry and Western blot, respectively. Tissue explants were used to determine the effect of LL-37 on pro-labour mediators. hCAP18 was localised to the amnion epithelium, cytotrophoblasts and decidua in the foetal membranes, and in the longitudinal and transverse muscle fibres of the myometrium. Additional hCAP18 staining was present in leukocytes. In foetal membranes and myometrium, human labour was associated with significantly higher hCAP18 protein expression. Treatment of foetal membranes and myometrium with LL-37 significantly induced the expression and secretion of the pro-inflammatory cytokines IL-6 and TNF-α, and the chemokines IL-8 and MCP-1. LL-37 also induced expression of MMP-9 mRNA and pro MMP-9 expression in foetal membranes. Co-treatment with BAY 11-7082 was associated with a decrease in LL-37-induced pro-inflammatory cytokine expression. Moreover, inhibition of MyD88 in myometrial cells decreased LL-37-induced pro-inflammatory cytokine expression and release. LL-37 also significantly increased NF-κB transcriptional activity. In conclusion, hCAP18/LL-37 induces pro-inflammatory and pro-labour mediators, via the MyD88/NF-κB pathway.
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Affiliation(s)
- Ratana Lim
- Mercy Perinatal Research Centre, Mercy Hospital for Women, Heidelberg, Victoria, Australia; Obstetrics, Nutrition and Endocrinology Group, Department of Obstetrics and Gynaecology, University of Melbourne, Victoria, Australia
| | - Gillian Barker
- Mercy Perinatal Research Centre, Mercy Hospital for Women, Heidelberg, Victoria, Australia; Obstetrics, Nutrition and Endocrinology Group, Department of Obstetrics and Gynaecology, University of Melbourne, Victoria, Australia
| | - Martha Lappas
- Mercy Perinatal Research Centre, Mercy Hospital for Women, Heidelberg, Victoria, Australia; Obstetrics, Nutrition and Endocrinology Group, Department of Obstetrics and Gynaecology, University of Melbourne, Victoria, Australia.
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Gawron K, Bereta G, Nowakowska Z, Lazarz-Bartyzel K, Lazarz M, Szmigielski B, Mizgalska D, Buda A, Koziel J, Oruba Z, Chomyszyn-Gajewska M, Potempa J. Peptidylarginine deiminase from Porphyromonas gingivalis contributes to infection of gingival fibroblasts and induction of prostaglandin E2 -signaling pathway. Mol Oral Microbiol 2014; 29:321-32. [PMID: 25176110 DOI: 10.1111/omi.12081] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/23/2014] [Indexed: 12/27/2022]
Abstract
Porphyromonas gingivalis (P. gingivalis) expres-ses the enzyme peptidylarginine deiminase (PPAD), which has a strong preference for C-terminal arginines. Due to the combined activity of PPAD and Arg-specific gingipains, P. gingivalis on the cell surface is highly citrullinated. To investigate the contribution of PPAD to the interaction of P. gingivalis with primary human gingival fibroblasts (PHGF) and P. gingivalis-induced synthesis of prostaglandin E2 (PGE2 ), PHGF were infected with wild-type P. gingivalis ATCC 33277, an isogenic PPAD-knockout strain (∆ppad) or a mutated strain (C351A) expressing an inactive enzyme in which the catalytic cysteine has been mutated to alanine (PPAD(C351A) ). Cells were infected in medium containing the mutants alone or in medium supplemented with purified, active PPAD. PHGF infection was assessed by colony-forming assay, microscopic analysis and flow cytometry. Expression of cyclo-oxygenase 2 (COX-2) and microsomal PGE synthase-1 (mPGES-1), key factors in the prostaglandin synthesis pathway, was examined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), while PGE2 synthesis was evaluated by enzyme immunoassay. PHGF were infected more efficiently by wild-type P. gingivalis than by the ∆ppad strain, which correlated with strong induction of COX-2 and mPGES-1 expression by wild-type P. gingivalis, but not by the PPAD activity-null mutant strains (Δppad and C351A). The impaired ability of the Δppad strain to adhere to and/or invade PHGF and both Δppad and C351A to stimulate the PGE2 -synthesis pathway was fully restored by the addition of purified PPAD. The latter effect was strongly inhibited by aspirin. Collectively, our results implicate PPAD activity, but not PPAD itself, as an important factor for gingival fibroblast infection and activation of PGE2 synthesis, the latter of which may strongly contribute to bone resorption and eventual tooth loss.
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Affiliation(s)
- K Gawron
- Microbiology Department, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
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Host defense peptides: front-line immunomodulators. Trends Immunol 2014; 35:443-50. [DOI: 10.1016/j.it.2014.07.004] [Citation(s) in RCA: 349] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 07/10/2014] [Accepted: 07/11/2014] [Indexed: 12/30/2022]
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High-quality 3D structures shine light on antibacterial, anti-biofilm and antiviral activities of human cathelicidin LL-37 and its fragments. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:2160-72. [PMID: 24463069 DOI: 10.1016/j.bbamem.2014.01.016] [Citation(s) in RCA: 123] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 12/26/2013] [Accepted: 01/10/2014] [Indexed: 01/07/2023]
Abstract
Host defense antimicrobial peptides are key components of human innate immunity that plays an indispensible role in human health. While there are multiple copies of cathelicidin genes in horses, cattle, pigs, and sheep, only one cathelicidin gene is found in humans. Interestingly, this single cathelicidin gene can be processed into different forms of antimicrobial peptides. LL-37, the most commonly studied form, is not only antimicrobial but also possesses other functional roles such as chemotaxis, apoptosis, wound healing, immune modulation, and cancer metastasis. This article reviews recent advances made in structural and biophysical studies of human LL-37 and its fragments, which serve as a basis to understand their antibacterial, anti-biofilm and antiviral activities. High-quality structures were made possible by using improved 2D NMR methods for peptide fragments and 3D NMR spectroscopy for intact LL-37. The two hydrophobic domains in the long amphipathic helix (residues 2-31) of LL-37 separated by a hydrophilic residue serine 9 explain its cooperative binding to bacterial lipopolysaccharides (LPS). Both aromatic rings (F5, F6, F17, and F27) and interfacial basic amino acids of LL-37 directly interact with anionic phosphatidylglycerols (PG). Although the peptide sequences reported in the literature vary slightly, there is a consensus that the central helix of LL-37 is essential for disrupting superbugs (e.g., MRSA), bacterial biofilms, and viruses such as human immunodeficiency virus 1 (HIV-1) and respiratory syncytial virus (RSV). In the central helix, the central arginine R23 is of particular importance in binding to bacterial membranes or DNA. Mapping the functional roles of the cationic amino acids of the major antimicrobial region of LL-37 provides a basis for designing antimicrobial peptides with desired properties. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova.
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SPINK9 stimulates metalloprotease/EGFR-dependent keratinocyte migration via purinergic receptor activation. J Invest Dermatol 2014; 134:1645-1654. [PMID: 24441102 DOI: 10.1038/jid.2014.23] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 12/10/2013] [Indexed: 02/06/2023]
Abstract
Serine protease inhibitors of the Kazal-type 9 (SPINK9) is a keratinocyte-derived cationic peptide that is found most abundantly in the upper layers of the palmar-plantar epidermis. In vitro, the peptide displays the capacity to inhibit specifically kallikrein-related peptidase 5 (KLK5). Here, we report that cells expressing SPINK9 secrete the peptide constitutively. Recombinant SPINK9 (rSPINK9) provoked transactivation of the EGFR in human keratinocytes, resulting in efficient downstream triggering of cell migration. Transactivation occurred via functional upregulation of a disintegrin and metalloproteases (ADAMs), as evidenced by suppression with a metalloproteinase inhibitor and an EGFR-blocking antibody. SPINK9 preparations isolated from human skin also displayed EGFR-transactivating capacity. The classical purinergic receptor antagonists oxidized ATP and pyridoxalphosphate-6-azophenyl-2',4',-disulfonic acid effectively suppressed EGFR transactivation by rSPINK9, indicating that in analogy to what has recently been reported for the cationic antimicrobial peptides cathelicidin LL-37 and bee venom melittin, purinergic receptors have an essential bridging role in promoting the upregulation of ADAM function by the cationic peptide. SPINK9 could represent an example of how a cationic peptide may subserve multiple and interrelated functions that contribute to the maintenance of the physical and immunological barrier of the skin.
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Kahlenberg JM, Kaplan MJ. Little peptide, big effects: the role of LL-37 in inflammation and autoimmune disease. THE JOURNAL OF IMMUNOLOGY 2014; 191:4895-901. [PMID: 24185823 DOI: 10.4049/jimmunol.1302005] [Citation(s) in RCA: 287] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The innate immune system utilizes many approaches for defense against invading microorganisms, including complement-mediated lysis, engulfment, formation of neutrophil extracellular traps, and release of antimicrobial peptides. Although classically thought to be driven by adaptive immunity, the development of autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus is increasingly associated with dysregulated innate immune pathways. An emerging theme within this literature is the contribution of antimicrobial peptides to the development of autoimmune disorders. This is best exemplified in atopic dermatitis and psoriasis where the defensins and the single human cathelicidin, LL-37, may contribute to disease. Furthermore, in the past few years, a role for LL-37 has emerged in the pathogenesis of systemic lupus erythematosus, rheumatoid arthritis, atherosclerosis, and possibly other diseases. In this review, we discuss the role of LL-37 and its murine ortholog, mCRAMP, in the modulation of immune and inflammatory pathways and their effects on autoimmune and inflammatory diseases.
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Affiliation(s)
- J Michelle Kahlenberg
- Division of Rheumatology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
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Antimicrobial peptides. Pharmaceuticals (Basel) 2013; 6:1543-75. [PMID: 24287494 PMCID: PMC3873676 DOI: 10.3390/ph6121543] [Citation(s) in RCA: 835] [Impact Index Per Article: 75.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 11/21/2013] [Accepted: 11/25/2013] [Indexed: 12/20/2022] Open
Abstract
The rapid increase in drug-resistant infections has presented a serious challenge to antimicrobial therapies. The failure of the most potent antibiotics to kill “superbugs” emphasizes the urgent need to develop other control agents. Here we review the history and new development of antimicrobial peptides (AMPs), a growing class of natural and synthetic peptides with a wide spectrum of targets including viruses, bacteria, fungi, and parasites. We summarize the major types of AMPs, their modes of action, and the common mechanisms of AMP resistance. In addition, we discuss the principles for designing effective AMPs and the potential of using AMPs to control biofilms (multicellular structures of bacteria embedded in extracellular matrixes) and persister cells (dormant phenotypic variants of bacterial cells that are highly tolerant to antibiotics).
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Ma Y, Zhao Y, Walker RK, Berkowitz GA. Molecular steps in the immune signaling pathway evoked by plant elicitor peptides: Ca2+-dependent protein kinases, nitric oxide, and reactive oxygen species are downstream from the early Ca2+ signal. PLANT PHYSIOLOGY 2013; 163:1459-71. [PMID: 24019427 PMCID: PMC3813664 DOI: 10.1104/pp.113.226068] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Endogenous plant elicitor peptides (Peps) can act to facilitate immune signaling and pathogen defense responses. Binding of these peptides to the Arabidopsis (Arabidopsis thaliana) plasma membrane-localized Pep receptors (PEPRs) leads to cytosolic Ca(2+) elevation, an early event in a signaling cascade that activates immune responses. This immune response includes the amplification of signaling evoked by direct perception of pathogen-associated molecular patterns by plant cells under assault. Work included in this report further characterizes the Pep immune response and identifies new molecular steps in the signal transduction cascade. The PEPR coreceptor BRASSINOSTEROID-INSENSITIVE1 Associated Kinase1 contributes to generation of the Pep-activated Ca(2+) signal and leads to increased defense gene expression and resistance to a virulent bacterial pathogen. Ca(2+)-dependent protein kinases (CPKs) decode the Ca(2+) signal, also facilitating defense gene expression and enhanced resistance to the pathogen. Nitric oxide and reduced nicotinamide adenine dinucleotide phosphate oxidase-dependent reactive oxygen species generation (due to the function of Respiratory Burst Oxidase Homolog proteins D and F) are also involved downstream from the Ca(2+) signal in the Pep immune defense signal transduction cascade, as is the case with BRASSINOSTEROID-INSENSITIVE1 Associated Kinase1 and CPK5, CPK6, and CPK11. These steps of the pathogen defense response are required for maximal Pep immune activation that limits growth of a virulent bacterial pathogen in the plant. We find a synergism between function of the PEPR and Flagellin Sensing2 receptors in terms of both nitric oxide and reactive oxygen species generation. Presented results are also consistent with the involvement of the secondary messenger cyclic GMP and a cyclic GMP-activated Ca(2+)-conducting channel in the Pep immune signaling pathway.
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Duplantier AJ, van Hoek ML. The Human Cathelicidin Antimicrobial Peptide LL-37 as a Potential Treatment for Polymicrobial Infected Wounds. Front Immunol 2013; 4:143. [PMID: 23840194 PMCID: PMC3699762 DOI: 10.3389/fimmu.2013.00143] [Citation(s) in RCA: 158] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2013] [Accepted: 05/28/2013] [Indexed: 12/30/2022] Open
Abstract
Diabetic patients often have ulcers on their lower-limbs that are infected by multiple biofilm-forming genera of bacteria, and the elimination of the biofilm has proven highly successful in resolving such wounds in patients. To that end, antimicrobial peptides have shown potential as a new anti-biofilm approach. The single human cathelicidin peptide LL-37 has been shown to have antimicrobial and anti-biofilm activity against multiple Gram-positive and Gram-negative human pathogens, and have wound-healing effects on the host. The combination of the anti-biofilm effect and wound-healing properties of LL-37 may make it highly effective in resolving polymicrobially infected wounds when topically applied. Such a peptide or its derivatives could be a platform from which to develop new therapeutic strategies to treat biofilm-mediated infections of wounds. This review summarizes known mechanisms that regulate the endogenous levels of LL-37 and discusses the anti-biofilm, antibacterial, and immunological effects of deficient vs. excessive concentrations of LL-37 within the wound environment. Here, we review recent advances in understanding the therapeutic potential of this peptide and other clinically advanced peptides as a potential topical treatment for polymicrobial infected wounds.
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Affiliation(s)
- Allen J Duplantier
- National Center for Biodefense and Infectious Diseases, George Mason University , Manassas, VA , USA
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Säll J, Carlsson M, Gidlöf O, Holm A, Humlén J, Ohman J, Svensson D, Nilsson BO, Jönsson D. The antimicrobial peptide LL-37 alters human osteoblast Ca2+ handling and induces Ca2+-independent apoptosis. J Innate Immun 2013; 5:290-300. [PMID: 23406612 DOI: 10.1159/000346587] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Accepted: 12/17/2012] [Indexed: 11/19/2022] Open
Abstract
The human antimicrobial peptide cathelicidin LL-37 has, besides its antimicrobial properties, also been shown to regulate apoptosis in a cell type-specific manner. Mechanisms involved in LL-37-regulated apoptotic signaling are not identified. Here, we show that LL-37 reduces the human osteoblast-like MG63 cell number and cell viability in the micromolar concentration range with an IC50 value of about 5 µM. Treatment with 4 µM LL-37 increased the number of annexin V-positive cells and stimulated activation of caspase 3 showing that LL-37 promotes apoptosis. Treatment with 4 µM LL-37 caused an acute and sustained rise in intracellular Ca(2+) concentration assessed by laser-scanning confocal microscopy of Fluo-4-AM-loaded MG63 cells. LL-37 increased Ca(2+) also in the presence of the respective L- and T-type voltage-sensitive Ca(2+) channel blockers nifedipine and NiCl2. LL-37 had no effect on Ca(2+) in cells incubated with Ca(2+)-free solution. LL-37 (4 and 8 µM) reduced the MG63 cell number both in the presence and absence of Ca(2+) in the medium. In conclusion, LL-37 reduces the osteoblast cell number by promoting apoptosis, and furthermore, LL-37 stimulates Ca(2+) inflow via a mechanism independent of voltage-sensitive Ca(2+) channels. Interestingly, LL-37-induced lowering of the cell number seems to be mediated via a mechanism independent of Ca(2+).
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Affiliation(s)
- Johanna Säll
- Department of Experimental Medical Science, Lund University, Lund, Sweden
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39
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Mishra B, Epand RF, Epand RM, Wang G. Structural location determines functional roles of the basic amino acids of KR-12, the smallest antimicrobial peptide from human cathelicidin LL-37. RSC Adv 2013. [PMID: 24307932 DOI: 10.1039/c3ra42599a] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cationic antimicrobial peptides are recognized templates for developing a new generation of antimicrobials to combat superbugs. Human cathelicidin LL-37 is an essential host defense molecule in human innate immunity. Previously, we identified KR-12 as the smallest antibacterial peptide of LL-37. KR-12 has a narrow activity spectrum since it is active against Gram-negative Escherichia coli but not Gram-positive Staphylococcus aureus. The functional roles of the basic amino acids of KR-12, however, have not yet been elucidated. An alanine scan of cationic amino acids of KR-12 provided evidence for their distinct roles in the activities of the peptides. Bacterial killing and membrane permeation experiments indicate that the R23A and K25A mutants, as well as the lysine-to-arginine mutant, were more potent than KR-12. Another three cationic residues (K18, R19, and R29) of KR-12, which are located in the hydrophilic face of the amphiphathic helix, appeared to be more important in clustering anionic lipids or hemolysis than R23 and K25 in the interfacial region. While the loss of interfacial R23 or K25 reduced peptide helicity, underscoring its important role in membrane binding, the overall increase in peptide activity of KR-12 could be ascribed to the increased peptide hydrophobicity that outweighed the role of basic charge in this case. In contrast, the mutations of interfacial R23 or K25 reduced peptide bactericidal activity of GF-17, an overlapping, more hydrophobic and potent peptide also derived from LL-37. Thus, the hydrophobic context of the peptide determines whether an alanine substitution of an interfacial basic residue increases or decreases membrane permeation and peptide activity.
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Affiliation(s)
- Biswajit Mishra
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, 986495 Nebraska Medical Center, Omaha, NE 68198-6495, USA
| | - Raquel F Epand
- Biochemistry and Biomedical Sciences, McMaster University Health Sciences Centre, Hamilton, Ontario, L8S 4K1, Canada
| | - Richard M Epand
- Biochemistry and Biomedical Sciences, McMaster University Health Sciences Centre, Hamilton, Ontario, L8S 4K1, Canada
| | - Guangshun Wang
- Department of Pathology and Microbiology, College of Medicine, University of Nebraska Medical Center, 986495 Nebraska Medical Center, Omaha, NE 68198-6495, USA
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40
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A comprehensive summary of LL-37, the factotum human cathelicidin peptide. Cell Immunol 2012; 280:22-35. [PMID: 23246832 DOI: 10.1016/j.cellimm.2012.11.009] [Citation(s) in RCA: 400] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 11/09/2012] [Accepted: 11/15/2012] [Indexed: 01/01/2023]
Abstract
Cathelicidins are a group of antimicrobial peptides. Since their discovery, it has become clear that they are an exceptional class of peptides, with some members having pleiotropic effects. Not only do they possess an antibacterial, antifungal and antiviral function, they also show a chemotactic and immunostimulatory/-modulatory effect. Moreover, they are capable of inducing wound healing, angiogenesis and modulating apoptosis. Recent insights even indicate for a role of these peptides in cancer. This review provides a comprehensive summary of the most recent and relevant insights concerning the human cathelicidin LL-37.
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41
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Barabas N, Röhrl J, Holler E, Hehlgans T. Beta-defensins activate macrophages and synergize in pro-inflammatory cytokine expression induced by TLR ligands. Immunobiology 2012; 218:1005-11. [PMID: 23332217 DOI: 10.1016/j.imbio.2012.11.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/21/2012] [Accepted: 11/22/2012] [Indexed: 11/19/2022]
Abstract
Our previous studies indicated that mouse beta defensin 14 (mBD14, Defb14), a newly identified member of the beta-defensin super family, interacts with the chemokine receptors CCR2 and CCR6. In this study we report that pre-stimulation of primary mouse macrophages with mBD14 results in a synergistic, enhanced expression of pro-inflammatory cytokines and chemokines induced by TLR ligand re-stimulation. Experiments using specific inhibitors of G(i)-protein-coupled receptor signaling provide evidence that this effect seems to be mediated by a G(i)-protein-coupled receptor expressed on bone marrow derived macrophages. However, using primary macrophages derived from CCR6- and CCR2-deficient mice clearly demonstrated that the enhanced pro-inflammatory cytokine and chemokine expression is independent of the chemokine receptors CCR6 and CCR2. Additionally, signaling pathway analysis indicated that mBD14 is capable of inducing MAPK ERK1/2 phosphorylation and the induction of CD86 and F4/80 expression in bone marrow-derived macrophages after mBD14 stimulation. Collectively, our data indicate that β-defensins activate primary macrophages and enhance pro-inflammatory responses by using G(i)PCRs in order to support inflammatory reactions induced by TLR ligands.
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Affiliation(s)
- Nicola Barabas
- Institute of Immunology, University of Regensburg, 93053 Regensburg, Germany
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42
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Abstract
During embryonic development, the skin, the largest organ of the human body, and nervous system are both derived from the neuroectoderm. Consequently, several key factors and mechanisms that influence and control central or peripheral nervous system activities are also present and hence involved in various regulatory mechanisms of the skin. Apparently, this is the case for the ion and non-ion selective channels as well. Therefore, in this review, we shall focus on delineating the regulatory roles of the channels in skin physiology and pathophysiology. First, we introduce key cutaneous functions and major characteristics of the channels in question. Then, we systematically detail the involvement of a multitude of channels in such skin processes (e.g. skin barrier formation, maintenance, and repair, immune mechanisms, exocrine secretion) which are mostly defined by cutaneous non-neuronal cell populations. Finally, we close by summarizing data suggesting that selected channels are also involved in skin diseases such as e.g. atopic dermatitis, psoriasis, non-melanoma cancers and malignant melanoma, genetic and autoimmune diseases, etc., as well as in skin ageing.
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Affiliation(s)
- Attila Oláh
- DE-MTA Lendület Cellular Physiology Research Group, Department of Physiology, University of Debrecen, Medical and Health Science Center, Research Center for Molecular Medicine, Nagyerdei krt. 98, H-4032, Debrecen, Hungary
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