1
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Sun J, Chen M, Hu Z, Xu N, Wang W, Ping Z, Zhu J, Sun D, Zhu Z, Li H, Ge X, Luo L, Zhou W, Bai R, Xu Z, Sheng J. Ribonuclease 4 functions as an intestinal antimicrobial protein to maintain gut microbiota and metabolite homeostasis. Nat Commun 2024; 15:5778. [PMID: 38987259 PMCID: PMC11237007 DOI: 10.1038/s41467-024-50223-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 07/03/2024] [Indexed: 07/12/2024] Open
Abstract
Antimicrobial proteins contribute to host-microbiota interactions and are associated with inflammatory bowel disease (IBD), but our understanding on antimicrobial protein diversity and functions remains incomplete. Ribonuclease 4 (Rnase4) is a potential antimicrobial protein with no known function in the intestines. Here we find that RNASE4 is expressed in intestinal epithelial cells (IEC) including Paneth and goblet cells, and is detectable in human and mouse stool. Results from Rnase4-deficient mice and recombinant protein suggest that Rnase4 kills Parasutterella to modulate intestinal microbiome, thereby enhancing indoleamine-2,3-dioxygenase 1 (IDO1) expression and subsequently kynurenic and xanthurenic acid production in IECs to reduce colitis susceptibility. Furthermore, deceased RNASE4 levels are observed in the intestinal tissues and stool from patients with IBD, correlating with increased stool Parasutterella. Our results thus implicate Rnase4 as an intestinal antimicrobial protein regulating gut microbiota and metabolite homeostasis, and as a potential diagnostic biomarker and therapeutic target for IBD.
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Affiliation(s)
- Jun Sun
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 310012, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Muxiong Chen
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Zhen Hu
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 310012, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Ningqin Xu
- Division of Health Sciences, Hangzhou Normal University, Hangzhou, 310015, China
| | - Wenguang Wang
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 310012, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Zejun Ping
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 310012, China
- Cancer Center, Zhejiang University, Hangzhou, 310058, China
| | - Jiayi Zhu
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Desen Sun
- Department of Biochemistry and Molecular Biology, and Zhejiang Key Laboratory of Pathophysiology, Medical School of Ningbo University, Ningbo, Zhejiang, 315211, China
| | - Zhehao Zhu
- College of Life Science, Zhejiang University, Hangzhou, 310058, China
| | - Hangyu Li
- College of Life Science, Zhejiang University, Hangzhou, 310058, China
| | - Xiaolong Ge
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Liang Luo
- Department of Gastroenterology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Wei Zhou
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Rongpan Bai
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.
| | - Zhengping Xu
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 310012, China.
- Cancer Center, Zhejiang University, Hangzhou, 310058, China.
| | - Jinghao Sheng
- Institute of Environmental Medicine and Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China.
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 310012, China.
- Cancer Center, Zhejiang University, Hangzhou, 310058, China.
- Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, China.
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2
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Rademacher F, Scheel A, Gläser R, Schröder L, Heinemann N, Bartels J, Gerdes S, Stölzl D, Rodriguez E, Döhner K, Weidinger S, Werfel T, Harder J. Inhibition of RNase 7 by RNase inhibitor promotes inflammation and Staphylococcus aureus growth: Implications for atopic dermatitis. Allergy 2024; 79:1573-1583. [PMID: 38641894 DOI: 10.1111/all.16125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 02/14/2024] [Accepted: 03/07/2024] [Indexed: 04/21/2024]
Abstract
BACKGROUND The antimicrobial ribonuclease RNase 7 is abundantly expressed in the epidermis of lesional skin of atopic dermatitis (AD). Host RNase inhibitor (RI) binds to RNase 7 and blocks its ribonuclease activity. This study aimed to evaluate the impact of RNase 7-RI interactions on AD. METHODS Cultured human primary keratinocytes, with siRNA-mediated downregulation of RNase 7 and RI, were stimulated with the synthetic RNA polyinosinic-polycytidylic acid (poly I:C). Induction of proinflammatory mediators was analyzed by real-time PCR and ELISA. RI expression in AD non-lesional and lesional skin biopsies and healthy controls was analyzed by real-time PCR and immunostaining. RI protein release in vivo on the AD skin surface was determined by western blot. Antimicrobial and ribonuclease assays were used to investigate the functional role of RI. RESULTS RNase 7 inhibited the RNA-induced expression of proinflammatory mediators in keratinocytes. Accordingly, downregulation of RNase 7 in keratinocytes enhanced RNA-mediated induction of proinflammatory mediators, whereas downregulation of RI had the opposite effect. RI was released by damaged keratinocytes and epidermis. In vivo expression and release of RI on the skin surface were enhanced in lesional AD skin. Rinsing solution from the surface of lesional AD skin blocked the ribonuclease activity of RNase 7. The anti-Staphylococcus aureus activity of RNase 7 was abrogated by RI. CONCLUSIONS Our data suggest a novel role of RI as a trigger factor of inflammation in AD by blocking the ribonuclease and antimicrobial activity of RNase 7, thereby enhancing RNA-mediated inflammation and S. aureus growth.
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Affiliation(s)
- Franziska Rademacher
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Annika Scheel
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Regine Gläser
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Lena Schröder
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Nina Heinemann
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Joachim Bartels
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Sascha Gerdes
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Dora Stölzl
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Elke Rodriguez
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Katinka Döhner
- Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany
- Hannover Medical School, Cluster of Excellence RESIST (EXC 2155), Hannover, Germany
| | - Stephan Weidinger
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
| | - Thomas Werfel
- Department of Dermatology and Allergy, Hannover Medical School, Hannover, Germany
- Hannover Medical School, Cluster of Excellence RESIST (EXC 2155), Hannover, Germany
| | - Jürgen Harder
- Department of Dermatology, Quincke Research Center, Kiel University, Kiel, Germany
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3
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Garnett ER, Raines RT. Emerging biological functions of ribonuclease 1 and angiogenin. Crit Rev Biochem Mol Biol 2021; 57:244-260. [PMID: 34886717 DOI: 10.1080/10409238.2021.2004577] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Pancreatic-type ribonucleases (ptRNases) are a large family of vertebrate-specific secretory endoribonucleases. These enzymes catalyze the degradation of many RNA substrates and thereby mediate a variety of biological functions. Though the homology of ptRNases has informed biochemical characterization and evolutionary analyses, the understanding of their biological roles is incomplete. Here, we review the functions of two ptRNases: RNase 1 and angiogenin. RNase 1, which is an abundant ptRNase with high catalytic activity, has newly discovered roles in inflammation and blood coagulation. Angiogenin, which promotes neovascularization, is now known to play roles in the progression of cancer and amyotrophic lateral sclerosis, as well as in the cellular stress response. Ongoing work is illuminating the biology of these and other ptRNases.
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Affiliation(s)
- Emily R Garnett
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ronald T Raines
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
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4
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Bender K, Schwartz LL, Cohen A, Vasquez CM, Murtha MJ, Eichler T, Thomas JP, Jackson A, Spencer JD. Expression and function of human ribonuclease 4 in the kidney and urinary tract. Am J Physiol Renal Physiol 2021; 320:F972-F983. [PMID: 33818125 DOI: 10.1152/ajprenal.00592.2020] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Antimicrobial peptides are essential host defense mechanisms that prevent urinary tract infections. Recent studies have demonstrated that peptides in the ribonuclease A superfamily have antimicrobial activity against uropathogens and protect the urinary tract from uropathogenic Escherichia coli (UPEC). Little is known about the antibacterial function or expression of ribonuclease 4 (RNase 4) in the human urinary tract. Here, we show that full-length recombinant RNase 4 peptide and synthetic amino-terminal RNase 4 peptide fragment have antibacterial activity against UPEC and multidrug-resistant (MDR)-UPEC. RNASE4 transcript expression was detected in human kidney and bladder tissue using quantitative real-time PCR. Immunostaining or in situ hybridization localized RNase 4 expression to proximal tubules, principal and intercalated cells in the kidney's collecting duct, and the bladder urothelium. Urinary RNase 4 concentrations were quantified in healthy controls and females with a history of urinary tract infection. Compared with controls, urinary RNase 4 concentrations were significantly lower in females with a history of urinary tract infection. When RNase 4 was neutralized in human urine or silenced in vitro using siRNA, urinary UPEC replication or attachment to and invasion of urothelial and kidney medullary cells increased. These data show that RNase 4 has antibacterial activity against UPEC, is expressed in the human urinary tract, and can contribute to host defense against urinary tract infections.NEW & NOTEWORTHY Ribonuclease 4 (RNase 4) is a newly identified host defense peptide in the human kidney and bladder. RNase 4 kills uropathogenic Escherichia coli (UPEC) and multidrug-resistant UPEC. RNase 4 prevents invasive UPEC infection and suppressed RNase 4 expression may be a risk factor for more severe or recurrent urinary tract infection.
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Affiliation(s)
- Kristin Bender
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Abigail Wexner Research Institute at Nationwide Children's Hospital, Center for Clinical and Translational Research, Columbus, Ohio
| | - Laura L Schwartz
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Abigail Wexner Research Institute at Nationwide Children's Hospital, Center for Clinical and Translational Research, Columbus, Ohio
| | - Ariel Cohen
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The University of Toledo College of Medicine and Life Sciences, Toledo, Ohio
| | - Claudia Mosquera Vasquez
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Abigail Wexner Research Institute at Nationwide Children's Hospital, Center for Clinical and Translational Research, Columbus, Ohio
| | - Matthew J Murtha
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Ohio State University College of Medicine, Columbus, Ohio
| | - Tad Eichler
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Abigail Wexner Research Institute at Nationwide Children's Hospital, Center for Clinical and Translational Research, Columbus, Ohio
| | - Jason P Thomas
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,Division of Nephrology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio
| | - Ashley Jackson
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Abigail Wexner Research Institute at Nationwide Children's Hospital, Center for Clinical and Translational Research, Columbus, Ohio.,The Ohio State University College of Medicine, Columbus, Ohio.,Division of Nephrology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio
| | - John David Spencer
- Nephrology and Urology Research Affinity Group, Nationwide Children's Hospital, Columbus, Ohio.,The Abigail Wexner Research Institute at Nationwide Children's Hospital, Center for Clinical and Translational Research, Columbus, Ohio.,The Ohio State University College of Medicine, Columbus, Ohio.,Division of Nephrology, Department of Pediatrics, Nationwide Children's Hospital, Columbus, Ohio
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5
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Redox Active Antimicrobial Peptides in Controlling Growth of Microorganisms at Body Barriers. Antioxidants (Basel) 2021; 10:antiox10030446. [PMID: 33805777 PMCID: PMC7998263 DOI: 10.3390/antiox10030446] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/05/2021] [Accepted: 03/09/2021] [Indexed: 01/14/2023] Open
Abstract
Epithelia in the skin, gut and other environmentally exposed organs display a variety of mechanisms to control microbial communities and limit potential pathogenic microbial invasion. Naturally occurring antimicrobial proteins/peptides and their synthetic derivatives (here collectively referred to as AMPs) reinforce the antimicrobial barrier function of epithelial cells. Understanding how these AMPs are functionally regulated may be important for new therapeutic approaches to combat microbial infections. Some AMPs are subject to redox-dependent regulation. This review aims to: (i) explore cysteine-based redox active AMPs in skin and intestine; (ii) discuss casual links between various redox environments of these barrier tissues and the ability of AMPs to control cutaneous and intestinal microbes; (iii) highlight how bacteria, through intrinsic mechanisms, can influence the bactericidal potential of redox-sensitive AMPs.
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6
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Chen J, Huang X, Geng R, Zhu D, Wang W, Liu H. Ribonuclease1 contributes to the antibacterial response and immune defense in blunt snout bream (Megalobrama amblycephala). Int J Biol Macromol 2021; 172:309-320. [PMID: 33454323 DOI: 10.1016/j.ijbiomac.2021.01.066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/15/2020] [Accepted: 01/12/2021] [Indexed: 12/14/2022]
Abstract
Ribonuclease 1 (RNase1) is a vertebrate-specific enzyme that mainly performs digestive activity in herbivorous mammals. Here we used bacterial viability assays to explore its antimicrobial activity in blunt snout bream (Megalobrama amblycephala). The results showed that Ma-RNase1 rapidly killed Gram-negative and Gram-positive bacteria at micromolar concentrations. Ma-RNase1 increased the permeability of bacterial outer and inner membranes, thus reducing the integrity of bacterial cell wall and membrane. Moreover, Ma-RNase1 effectively counteracted the tissue damage and apoptosis caused by Aeromonas hydrophila infection. Quantitative real-time PCR and immunoblot analysis indicated that RNase1 mRNA and protein were up-regulated in the kidney and gut during infection. Furthermore, A. hydrophila infection significantly induced Tnf-α and Il-1β mRNA expression in liver, but not in the RNase1 pre-treatment group. In addition, a significant increase in the expression of immune-related genes (Nf-κb and Tlr4) was found in liver, kidney and gut of A. hydrophila-infected fish, while a decrease in Myd88 and Tlr4 levels was found in liver, spleen, kidney and gut in the group pre-treated with RNase1. Collectively, these data suggest that Ma-RNase1 has antimicrobial function both in vitro and in vivo, and contributes to the protective effect and immune defense of blunt snout bream.
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Affiliation(s)
- Jing Chen
- College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key laboratory of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China
| | - Xin Huang
- College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key laboratory of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China
| | - Ruijing Geng
- College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key laboratory of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China
| | - Dongmei Zhu
- College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key laboratory of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China
| | - Weimin Wang
- College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key laboratory of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China.
| | - Han Liu
- College of Fisheries, Key Lab of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education/Key laboratory of Freshwater Animal Breeding, Ministry of Agriculture and Rural Affairs, Huazhong Agricultural University, Wuhan 430070, China.
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7
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Lacerda Mariano L, Ingersoll MA. The immune response to infection in the bladder. Nat Rev Urol 2020; 17:439-458. [PMID: 32661333 DOI: 10.1038/s41585-020-0350-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/09/2020] [Indexed: 12/22/2022]
Abstract
The bladder is continuously protected by passive defences such as a mucus layer, antimicrobial peptides and secretory immunoglobulins; however, these defences are occasionally overcome by invading bacteria that can induce a strong host inflammatory response in the bladder. The urothelium and resident immune cells produce additional defence molecules, cytokines and chemokines, which recruit inflammatory cells to the infected tissue. Resident and recruited immune cells act together to eradicate bacteria from the bladder and to develop lasting immune memory against infection. However, urinary tract infection (UTI) is commonly recurrent, suggesting that the induction of a memory response in the bladder is inadequate to prevent reinfection. Additionally, infection seems to induce long-lasting changes in the urothelium, which can render the tissue more susceptible to future infection. The innate immune response is well-studied in the field of UTI, but considerably less is known about how adaptive immunity develops and how repair mechanisms restore bladder homeostasis following infection. Furthermore, data demonstrate that sex-based differences in immunity affect resolution and infection can lead to tissue remodelling in the bladder following resolution of UTI. To combat the rise in antimicrobial resistance, innovative therapeutic approaches to bladder infection are currently in development. Improving our understanding of how the bladder responds to infection will support the development of improved treatments for UTI, particularly for those at risk of recurrent infection.
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Affiliation(s)
- Livia Lacerda Mariano
- Department of Immunology, Institut Pasteur, Paris, France.,Inserm, U1223, Paris, France
| | - Molly A Ingersoll
- Department of Immunology, Institut Pasteur, Paris, France. .,Inserm, U1223, Paris, France.
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8
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Becknell B, Ching C, Spencer JD. The Responses of the Ribonuclease A Superfamily to Urinary Tract Infection. Front Immunol 2019; 10:2786. [PMID: 31849967 PMCID: PMC6901906 DOI: 10.3389/fimmu.2019.02786] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 11/13/2019] [Indexed: 12/19/2022] Open
Abstract
The lower urinary tract is routinely exposed to microbes residing in the gastrointestinal tract, yet the urothelium resists invasive infections by gut microorganisms. This infection resistance is attributed to innate defenses in the bladder urothelium, kidney epithelium, and resident or circulating immune cells. In recent years, surmounting evidence suggests that these cell types produce and secrete soluble host defense peptides, including members of the Ribonuclease (RNase) A Superfamily, to combat invasive bacterial challenge. While some of these peptides, including RNase 4 and RNase 7, are abundantly produced by epithelial cells, the expression of others, like RNase 3 and RNase 6, increase at infection sites with immune cell recruitment. The objective of this mini-review is to highlight recent evidence showing the biological importance and responses of RNase A Superfamily members to infection in the kidney and bladder.
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Affiliation(s)
- Brian Becknell
- Nephrology and Urology Research Affinity Group, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Center of Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Division of Nephrology, Nationwide Children's Hospital, Columbus, OH, United States
| | - Christina Ching
- Nephrology and Urology Research Affinity Group, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Center of Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Division of Urology, Nationwide Children's Hospital, Columbus, OH, United States
| | - John David Spencer
- Nephrology and Urology Research Affinity Group, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Center of Clinical and Translational Research, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, OH, United States.,Division of Nephrology, Nationwide Children's Hospital, Columbus, OH, United States
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9
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Gotte G, Menegazzi M. Biological Activities of Secretory RNases: Focus on Their Oligomerization to Design Antitumor Drugs. Front Immunol 2019; 10:2626. [PMID: 31849926 PMCID: PMC6901985 DOI: 10.3389/fimmu.2019.02626] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/22/2019] [Indexed: 12/11/2022] Open
Abstract
Ribonucleases (RNases) are a large number of enzymes gathered into different bacterial or eukaryotic superfamilies. Bovine pancreatic RNase A, bovine seminal BS-RNase, human pancreatic RNase 1, angiogenin (RNase 5), and amphibian onconase belong to the pancreatic type superfamily, while binase and barnase are in the bacterial RNase N1/T1 family. In physiological conditions, most RNases secreted in the extracellular space counteract the undesired effects of extracellular RNAs and become protective against infections. Instead, if they enter the cell, RNases can digest intracellular RNAs, becoming cytotoxic and having advantageous effects against malignant cells. Their biological activities have been investigated either in vitro, toward a number of different cancer cell lines, or in some cases in vivo to test their potential therapeutic use. However, immunogenicity or other undesired effects have sometimes been associated with their action. Nevertheless, the use of RNases in therapy remains an appealing strategy against some still incurable tumors, such as mesothelioma, melanoma, or pancreatic cancer. The RNase inhibitor (RI) present inside almost all cells is the most efficacious sentry to counteract the ribonucleolytic action against intracellular RNAs because it forms a tight, irreversible and enzymatically inactive complex with many monomeric RNases. Therefore, dimerization or multimerization could represent a useful strategy for RNases to exert a remarkable cytotoxic activity by evading the interaction with RI by steric hindrance. Indeed, the majority of the mentioned RNases can hetero-dimerize with antibody derivatives, or even homo-dimerize or multimerize, spontaneously or artificially. This can occur through weak interactions or upon introducing covalent bonds. Immuno-RNases, in particular, are fusion proteins representing promising drugs by combining high target specificity with easy delivery in tumors. The results concerning the biological features of many RNases reported in the literature are described and discussed in this review. Furthermore, the activities displayed by some RNases forming oligomeric complexes, the mechanisms driving toward these supramolecular structures, and the biological rebounds connected are analyzed. These aspects are offered with the perspective to suggest possible efficacious therapeutic applications for RNases oligomeric derivatives that could contemporarily lack, or strongly reduce, immunogenicity and other undesired side-effects.
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Affiliation(s)
- Giovanni Gotte
- Biological Chemistry Section, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Marta Menegazzi
- Biological Chemistry Section, Department of Neuroscience, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
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10
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Rademacher F, Dreyer S, Kopfnagel V, Gläser R, Werfel T, Harder J. The Antimicrobial and Immunomodulatory Function of RNase 7 in Skin. Front Immunol 2019; 10:2553. [PMID: 31749808 PMCID: PMC6848066 DOI: 10.3389/fimmu.2019.02553] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 10/15/2019] [Indexed: 11/13/2022] Open
Abstract
The human ribonuclease RNase 7 has been originally isolated from human skin and is a member of the human RNase A superfamily. RNase 7 is constantly released by keratinocytes and accumulates on the skin surface. The expression of RNase 7 in keratinocytes can be induced by diverse stimuli such as cytokines, growth factors, and microbial factors. RNase 7 exhibits a potent broad spectrum of antimicrobial activity against various microorganisms and contributes to control bacterial growth on the skin surface. The ribonuclease and antimicrobial activity of RNase 7 can be blocked by the endogenous ribonuclease inhibitor. There is also increasing evidence that RNase 7 exerts immunomodulatory activities and may participate in antiviral defense. In this review, we discuss how these characteristics of RNase 7 contribute to innate cutaneous defense and highlight its role in skin infection and inflammation. We also speculate how a potential dysregulation of RNase 7 promotes inflammatory skin diseases and if RNase 7 may have therapeutic potential.
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Affiliation(s)
| | - Sylvia Dreyer
- Division of Immunodermatology and Allergy Research, Department of Dermatology and Allergy, Hannover Medical School, Hanover, Germany
| | - Verena Kopfnagel
- Division of Immunodermatology and Allergy Research, Department of Dermatology and Allergy, Hannover Medical School, Hanover, Germany
- Hannover Unified Biobank, Hannover Medical School, Hanover, Germany
| | - Regine Gläser
- Department of Dermatology, University of Kiel, Kiel, Germany
| | - Thomas Werfel
- Division of Immunodermatology and Allergy Research, Department of Dermatology and Allergy, Hannover Medical School, Hanover, Germany
- Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hanover, Germany
| | - Jürgen Harder
- Department of Dermatology, University of Kiel, Kiel, Germany
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11
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Saxena V, Hains DS, Ketz J, Chanley M, Spencer JD, Becknell B, Pierce KR, Nelson RD, Purkerson JM, Schwartz GJ, Schwaderer AL. Cell-specific qRT-PCR of renal epithelial cells reveals a novel innate immune signature in murine collecting duct. Am J Physiol Renal Physiol 2018; 315:F812-F823. [PMID: 28468965 PMCID: PMC6230735 DOI: 10.1152/ajprenal.00512.2016] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 03/23/2017] [Accepted: 04/25/2017] [Indexed: 01/17/2023] Open
Abstract
The urinary tract is usually culture negative despite its close proximity to microbial flora. The precise mechanism by which the kidneys and urinary tract defends against infection is not well understood. The initial kidney cells to encounter ascending pathogens are the collecting tubule cells that consist of principal cells (PCs) that express aquaporin 2 (AQP2) and intercalated cells (ICs) that express vacuolar H+-ATPase (V-ATPase, B1 subunit). We have previously shown that ICs are involved with the human renal innate immune defense. Here we generated two reporter mice, VATPase B1-cre+tdT+ mice to fluorescently label ICs and AQP2-cre+tdT+ mice to fluorescently label PCs, and then performed flow sorting to enrich PCs and ICs for analysis. Isolated ICs and PCs along with proximal tubular cells were used to measure antimicrobial peptide (AMP) mRNA expression. ICs and PCs were significantly enriched for AMPs. Isolated ICs responded to uropathogenic Escherichia coli (UPEC) challenge in vitro and had higher RNase4 gene expression than control while both ICs and PCs responded to UPEC challenge in vivo by upregulating Defb1 mRNA expression. To our knowledge, this is the first report of isolating murine collecting tubule cells and performing targeted analysis for multiple classes of AMPs.
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Affiliation(s)
- Vijay Saxena
- The Research Institute at Nationwide Children's, Center for Clinical and Translational Research, Columbus, Ohio, and College of Medicine, Ohio State University , Columbus, Ohio
| | - David S Hains
- Innate Immunity Translational Research Center, Children's Foundation Research Institute at Le Bonheur Children's Hospital , Memphis, Tennessee
| | - John Ketz
- The Research Institute at Nationwide Children's, Center for Clinical and Translational Research, Columbus, Ohio, and College of Medicine, Ohio State University , Columbus, Ohio
| | - Melinda Chanley
- The Research Institute at Nationwide Children's, Center for Clinical and Translational Research, Columbus, Ohio, and College of Medicine, Ohio State University , Columbus, Ohio
| | - John D Spencer
- The Research Institute at Nationwide Children's, Center for Clinical and Translational Research, Columbus, Ohio, and College of Medicine, Ohio State University , Columbus, Ohio
| | - Brian Becknell
- The Research Institute at Nationwide Children's, Center for Clinical and Translational Research, Columbus, Ohio, and College of Medicine, Ohio State University , Columbus, Ohio
| | - Keith R Pierce
- Innate Immunity Translational Research Center, Children's Foundation Research Institute at Le Bonheur Children's Hospital , Memphis, Tennessee
| | - Raoul D Nelson
- Division of Nephrology, Department of Pediatrics, University of Utah , Salt Lake City, Utah
| | - Jeffrey M Purkerson
- University of Rochester Medical Center, School of Medicine and Dentistry , Rochester, New York
| | - George J Schwartz
- University of Rochester Medical Center, School of Medicine and Dentistry , Rochester, New York
| | - Andrew L Schwaderer
- The Research Institute at Nationwide Children's, Center for Clinical and Translational Research, Columbus, Ohio, and College of Medicine, Ohio State University , Columbus, Ohio
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12
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Tavernier Q, Bennana E, Poindessous V, Schaeffer C, Rampoldi L, Pietrancosta N, Pallet N. Regulation of IRE1 RNase activity by the Ribonuclease inhibitor 1 (RNH1). Cell Cycle 2018; 17:1901-1916. [PMID: 30109813 DOI: 10.1080/15384101.2018.1506655] [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: 10/27/2022] Open
Abstract
Adaptation to endoplasmic reticulum (ER) stress depends on the activation of the sensor inositol-requiring enzyme 1α (IRE1), an endoribonuclease that splices the mRNA of the transcription factor XBP1 (X-box-binding protein 1). To better understand the protein network that regulates the activity of the IRE1 pathway, we systematically screened the proteins that interact with IRE1 and identified a ribonuclease inhibitor called ribonuclease/angiogenin inhibitor 1 (RNH1). RNH1 is a leucine-rich repeat domains-containing protein that binds to and inhibits ribonucleases. Immunoprecipitation experiments confirmed this interaction. Docking experiments indicated that RNH1 physically interacts with IRE1 through its cytosolic RNase domain. Upon ER stress, the interaction of RNH1 with IRE1 in the ER increased at the expense of the nuclear pool of RNH1. Inhibition of RNH1 expression using siRNA mediated RNA interference upon ER stress led to an increased splicing activity of XBP1. Modulation of IRE1 RNase activity by RNH1 was recapitulated in a cell-free system, suggesting direct regulation of IRE1 by RNH. We conclude that RNH1 attenuates the activity of IRE1 by interacting with its ribonuclease domain. These findings have implications for understanding the molecular mechanism by which IRE1 signaling is attenuated upon ER stress.
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Affiliation(s)
- Quentin Tavernier
- a Institut National de la Santé et de la Recherche Médicale (INSERM) U1147 , Paris , France.,b Paris Descartes University , Paris , France
| | - Evangeline Bennana
- b Paris Descartes University , Paris , France.,c 3P5 Proteomic facility, COMUE Sorbonne Paris Cité , Université Paris Descartes , Paris , France
| | - Virginie Poindessous
- a Institut National de la Santé et de la Recherche Médicale (INSERM) U1147 , Paris , France.,b Paris Descartes University , Paris , France
| | - Celine Schaeffer
- d Molecular Genetics of Renal Disorders Unit, Division of Genetics and Cell Biology , IRCCS San Raffaele Scientific Institute , Milan , Italy
| | - Luca Rampoldi
- d Molecular Genetics of Renal Disorders Unit, Division of Genetics and Cell Biology , IRCCS San Raffaele Scientific Institute , Milan , Italy
| | - Nicolas Pietrancosta
- b Paris Descartes University , Paris , France.,e Centre National pour la Recherche Scientifique (CNRS) U8601 , Paris , France.,f Team Chemistry and Biology, Modeling & Immunology for Therapy , CBMIT, 2MI Platform , Paris , France
| | - Nicolas Pallet
- a Institut National de la Santé et de la Recherche Médicale (INSERM) U1147 , Paris , France.,b Paris Descartes University , Paris , France.,g Clinical Chemistry Department , Hôpital Européen Gorges Pompidou, APHP , Paris , France.,h Plate-forme Proteomique 3P5 , Universite Paris Descartes, Sorbonne Paris Cite , Paris , France
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13
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Lu L, Li J, Moussaoui M, Boix E. Immune Modulation by Human Secreted RNases at the Extracellular Space. Front Immunol 2018; 9:1012. [PMID: 29867984 PMCID: PMC5964141 DOI: 10.3389/fimmu.2018.01012] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/23/2018] [Indexed: 12/23/2022] Open
Abstract
The ribonuclease A superfamily is a vertebrate-specific family of proteins that encompasses eight functional members in humans. The proteins are secreted by diverse innate immune cells, from blood cells to epithelial cells and their levels in our body fluids correlate with infection and inflammation processes. Recent studies ascribe a prominent role to secretory RNases in the extracellular space. Extracellular RNases endowed with immuno-modulatory and antimicrobial properties can participate in a wide variety of host defense tasks, from performing cellular housekeeping to maintaining body fluid sterility. Their expression and secretion are induced in response to a variety of injury stimuli. The secreted proteins can target damaged cells and facilitate their removal from the focus of infection or inflammation. Following tissue damage, RNases can participate in clearing RNA from cellular debris or work as signaling molecules to regulate the host response and contribute to tissue remodeling and repair. We provide here an overall perspective on the current knowledge of human RNases’ biological properties and their role in health and disease. The review also includes a brief description of other vertebrate family members and unrelated extracellular RNases that share common mechanisms of action. A better knowledge of RNase mechanism of actions and an understanding of their physiological roles should facilitate the development of novel therapeutics.
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Affiliation(s)
- Lu Lu
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Jiarui Li
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Mohammed Moussaoui
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
| | - Ester Boix
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
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14
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Zaporozhchenko IA, Ponomaryova AA, Rykova EY, Laktionov PP. The potential of circulating cell-free RNA as a cancer biomarker: challenges and opportunities. Expert Rev Mol Diagn 2018; 18:133-145. [DOI: 10.1080/14737159.2018.1425143] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Ivan A. Zaporozhchenko
- Laboratory of Molecular Medicine, Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia
- Laboratory of Biomedical Technologies, Centre of New Surgical Technologies, E.N. Meshalkin Siberian Federal Biomedical Research Center, Novosibirsk, Russia
| | - Anastasia A. Ponomaryova
- Laboratory of Immunology, Tomsk Cancer Research Institute of SB RAMS, Tomsk, Russia
- Department of Applied Physics, National Research Tomsk Polytechnic University, Tomsk, Russia
| | - Elena Yu Rykova
- Laboratory of Molecular Medicine, Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia
- Laboratory of Biomedical Technologies, Centre of New Surgical Technologies, E.N. Meshalkin Siberian Federal Biomedical Research Center, Novosibirsk, Russia
| | - Pavel P. Laktionov
- Laboratory of Molecular Medicine, Institute of Chemical Biology and Fundamental Medicine of SB RAS, Novosibirsk, Russia
- Laboratory of Biomedical Technologies, Centre of New Surgical Technologies, E.N. Meshalkin Siberian Federal Biomedical Research Center, Novosibirsk, Russia
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15
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Mohammed I, Said DG, Dua HS. Human antimicrobial peptides in ocular surface defense. Prog Retin Eye Res 2017; 61:1-22. [DOI: 10.1016/j.preteyeres.2017.03.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 03/22/2017] [Accepted: 03/27/2017] [Indexed: 01/17/2023]
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16
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Earl CC, Smith MT, Lease RA, Bundy BC. Polyvinylsulfonic acid: A Low-cost RNase inhibitor for enhanced RNA preservation and cell-free protein translation. Bioengineered 2017; 9:90-97. [PMID: 28662363 PMCID: PMC5972934 DOI: 10.1080/21655979.2017.1313648] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The effectiveness and economics of polyvinyl sulfonic acid (PVSA) as a ribonuclease inhibitor for in vitro systems is reported. PVSA was shown to inhibit RNA cleavage in the presence of RNase A as well as in the presence of Escherichia coli lysate, suggesting that PVSA can act as a broader ribonuclease inhibitor. In addition, PVSA was shown to improve the integrity of mRNA transcripts by up to 5-fold in vitro as measured by their translational viability. Improved preservation of mRNA transcripts in the presence of PVSA under common RNA storage conditions is also reported. A cost comparison with commercially available RNAse inhibitors indicates the economic practicality of PVSA which is approximately 1,700 times less expensive than commonly used ribonuclease inhibitors. PVSA can also be separated from RNA by alcohol precipitation for applications that may be sensitive to the presence of PVSA.
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Affiliation(s)
- Conner C Earl
- a Department of Chemical Engineering , Brigham Young University , Provo , UT , USA
| | - Mark T Smith
- a Department of Chemical Engineering , Brigham Young University , Provo , UT , USA
| | - Richard A Lease
- b Department of Chemical and Biomolecular Engineering , The Ohio State University , Columbus OH USA
| | - Bradley C Bundy
- a Department of Chemical Engineering , Brigham Young University , Provo , UT , USA
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17
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Koczera P, Martin L, Marx G, Schuerholz T. The Ribonuclease A Superfamily in Humans: Canonical RNases as the Buttress of Innate Immunity. Int J Mol Sci 2016; 17:ijms17081278. [PMID: 27527162 PMCID: PMC5000675 DOI: 10.3390/ijms17081278] [Citation(s) in RCA: 88] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/29/2016] [Accepted: 08/01/2016] [Indexed: 12/18/2022] Open
Abstract
In humans, the ribonuclease A (RNase A) superfamily contains eight different members that have RNase activities, and all of these members are encoded on chromosome 14. The proteins are secreted by a large variety of different tissues and cells; however, a comprehensive understanding of these proteins’ physiological roles is lacking. Different biological effects can be attributed to each protein, including antiviral, antibacterial and antifungal activities as well as cytotoxic effects against host cells and parasites. Different immunomodulatory effects have also been demonstrated. This review summarizes the available data on the human RNase A superfamily and illustrates the significant role of the eight canonical RNases in inflammation and the host defence system against infections.
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Affiliation(s)
- Patrick Koczera
- Department of Intensive Care and Intermediate Care, University Hospital Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Aachen 52074, Germany.
- Department for Experimental Molecular Imaging, University Hospital RWTH Aachen and Helmholtz Institute for Biomedical Engineering, RWTH Aachen University, Aachen 52074, Germany.
| | - Lukas Martin
- Department of Intensive Care and Intermediate Care, University Hospital Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Aachen 52074, Germany.
| | - Gernot Marx
- Department of Intensive Care and Intermediate Care, University Hospital Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Aachen 52074, Germany.
| | - Tobias Schuerholz
- Department of Intensive Care and Intermediate Care, University Hospital Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Aachen 52074, Germany.
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18
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Eichler TE, Becknell B, Easterling RS, Ingraham SE, Cohen DM, Schwaderer AL, Hains DS, Li B, Cohen A, Metheny J, Tridandapani S, Spencer JD. Insulin and the phosphatidylinositol 3-kinase signaling pathway regulate Ribonuclease 7 expression in the human urinary tract. Kidney Int 2016; 90:568-79. [PMID: 27401534 DOI: 10.1016/j.kint.2016.04.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/12/2016] [Accepted: 04/28/2016] [Indexed: 10/21/2022]
Abstract
Diabetes mellitus is a systemic disease associated with a deficiency of insulin production or action. Diabetic patients have an increased susceptibility to infection with the urinary tract being the most common site. Recent studies suggest that Ribonuclease 7 (RNase 7) is a potent antimicrobial peptide that plays an important role in protecting the urinary tract from bacterial insult. Because the impact of diabetes on RNase 7 expression and function are unknown, we investigated the effects of insulin on RNase 7 using human urine specimens. The urinary RNase 7 concentrations were measured in healthy control patients and insulin-deficient type 1 diabetics before and after starting insulin therapy. Compared with controls, diabetic patients had suppressed urinary RNase 7 concentrations, which increased with insulin. Using primary human urothelial cells, the mechanisms by which insulin stimulates RNase 7 synthesis were next explored. Insulin induced RNase 7 production via the phosphatidylinositide 3-kinase signaling pathway (PI3K/AKT) to shield urothelial cells from uropathogenic E. coli. In contrast, uropathogenic E. coli suppressed PI3K/AKT activity and RNase 7 production. Thus, insulin and PI3K/AKT signaling are essential for RNase 7 expression and increased infection risks in diabetic patients may be secondary to suppressed RNase 7 production. Our data may provide unique insight into novel urinary tract infection therapeutic strategies in at-risk populations.
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Affiliation(s)
- Tad E Eichler
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Brian Becknell
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - Robert S Easterling
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; University of Toledo College of Medicine and Life Sciences, Toledo, Ohio, USA
| | - Susan E Ingraham
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - Daniel M Cohen
- Division of Emergency Medicine, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - Andrew L Schwaderer
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA
| | - David S Hains
- Innate Immunity Translational Research Center, Department of Pediatrics, Children's Foundation Research Institute at Le Bonheur Children's Hospital, Memphis, Tennessee, USA
| | - Birong Li
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Ariel Cohen
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Jackie Metheny
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA
| | - Susheela Tridandapani
- Department of Internal Medicine, Comprehensive Cancer Center, The Ohio State University James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA; Department of Molecular Virology, Immunology, and Medical Genetics, Comprehensive Cancer Center, The Ohio State University James Cancer Hospital and Richard J. Solove Research Institute, Columbus, Ohio, USA
| | - John David Spencer
- Center for Clinical and Translational Research, Department of Pediatrics, The Research Institute at Nationwide Children's, Columbus, Ohio, USA; Division of Nephrology, Department of Pediatrics, Nationwide Children's, Columbus, Ohio, USA.
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19
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Salazar VA, Arranz-Trullén J, Navarro S, Blanco JA, Sánchez D, Moussaoui M, Boix E. Exploring the mechanisms of action of human secretory RNase 3 and RNase 7 against Candida albicans. Microbiologyopen 2016; 5:830-845. [PMID: 27277554 PMCID: PMC5061719 DOI: 10.1002/mbo3.373] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Revised: 03/30/2016] [Accepted: 04/04/2016] [Indexed: 12/17/2022] Open
Abstract
Human antimicrobial RNases, which belong to the vertebrate RNase A superfamily and are secreted upon infection, display a wide spectrum of antipathogen activities. In this work, we examined the antifungal activity of the eosinophil RNase 3 and the skin-derived RNase 7, two proteins expressed by innate cell types that are directly involved in the host defense against fungal infection. Candida albicans has been selected as a suitable working model for testing RNase activities toward a eukaryotic pathogen. We explored the distinct levels of action of both RNases on yeast by combining cell viability and membrane model assays together with protein labeling and confocal microscopy. Site-directed mutagenesis was applied to ablate either the protein active site or the key anchoring region for cell binding. This is the first integrated study that highlights the RNases' dual mechanism of action. Along with an overall membrane-destabilization process, the RNases could internalize and target cellular RNA. The data support the contribution of the enzymatic activity for the antipathogen action of both antimicrobial proteins, which can be envisaged as suitable templates for the development of novel antifungal drugs. We suggest that both human RNases work as multitasking antimicrobial proteins that provide a first line immune barrier.
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Affiliation(s)
- Vivian A Salazar
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain
| | - Javier Arranz-Trullén
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain
| | - Susanna Navarro
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain.,Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain
| | - Jose A Blanco
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain
| | - Daniel Sánchez
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain
| | - Mohammed Moussaoui
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain
| | - Ester Boix
- Department of Biochemistry and Molecular Biology, Faculty of Biosciences, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, E-08193, Spain.
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20
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Rademacher F, Simanski M, Harder J. RNase 7 in Cutaneous Defense. Int J Mol Sci 2016; 17:560. [PMID: 27089327 PMCID: PMC4849016 DOI: 10.3390/ijms17040560] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/07/2016] [Accepted: 04/08/2016] [Indexed: 02/07/2023] Open
Abstract
RNase 7 belongs to the RNase A superfamily and exhibits a broad spectrum of antimicrobial activity against various microorganisms. RNase 7 is expressed in human skin, and expression in keratinocytes can be induced by cytokines and microbes. These properties suggest that RNase 7 participates in innate cutaneous defense. In this review, we provide an overview about the role of RNase 7 in cutaneous defense with focus on the molecular mechanism of the antimicrobial activity of RNase 7, the regulation of RNase 7 expression, and the role of RNase 7 in skin diseases.
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Affiliation(s)
| | - Maren Simanski
- Department of Dermatology, University of Kiel, 24105 Kiel, Germany.
| | - Jürgen Harder
- Department of Dermatology, University of Kiel, 24105 Kiel, Germany.
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21
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Becknell B, Spencer JD. A Review of Ribonuclease 7's Structure, Regulation, and Contributions to Host Defense. Int J Mol Sci 2016; 17:423. [PMID: 27011175 PMCID: PMC4813274 DOI: 10.3390/ijms17030423] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 03/16/2016] [Accepted: 03/18/2016] [Indexed: 01/24/2023] Open
Abstract
The Ribonuclease A Superfamily is composed of a group of structurally similar peptides that are secreted by immune cells and epithelial tissues. Several members of the Ribonuclease A Superfamily demonstrate antimicrobial activity, and it has been suggested that some of these ribonucleases play an essential role in host defense. Ribonuclease 7 (RNase 7) is an epithelial-derived secreted peptide with potent broad-spectrum antimicrobial activity. This review summarizes the published literature on RNase 7’s antimicrobial properties, structure, regulation, and contributions to host defense. In doing so, we conclude by highlighting key knowledge gaps that must be investigated to completely understand the potential of developing RNase 7 as a novel therapeutic for human infectious diseases.
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Affiliation(s)
- Brian Becknell
- Center for Clinical and Translational Research, The Research Institute at Nationwide Children's, Columbus, OH 43205, USA.
- Division of Pediatric Nephrology, Nationwide Children's, Columbus, OH 43205, USA.
| | - John David Spencer
- Center for Clinical and Translational Research, The Research Institute at Nationwide Children's, Columbus, OH 43205, USA.
- Division of Pediatric Nephrology, Nationwide Children's, Columbus, OH 43205, USA.
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22
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Abstract
Urinary tract infections (UTIs), including pyelonephritis, are among the most common and serious infections encountered in nephrology practice. UTI risk is increased in selected patient populations with renal and urinary tract disorders. As the prevalence of antibiotic-resistant uropathogens increases, novel and alternative treatment options will be needed to reduce UTI-associated morbidity. Discoveries over the past decade demonstrate a fundamental role for the innate immune system in protecting the urothelium from bacterial challenge. Antimicrobial peptides, an integral component of this urothelial innate immune system, demonstrate potent bactericidal activity toward uropathogens and might represent a novel class of UTI therapeutics. The urothelium of the bladder and the renal epithelium secrete antimicrobial peptides into the urinary stream. In the kidney, intercalated cells--a cell-type involved in acid-base homeostasis--have been shown to be an important source of antimicrobial peptides. Intercalated cells have therefore become the focus of new investigations to explore their function during pyelonephritis and their role in maintaining urinary tract sterility. This Review provides an overview of UTI pathogenesis in the upper and lower urinary tract. We describe the role of intercalated cells and the innate immune response in preventing UTI, specifically highlighting the role of antimicrobial peptides in maintaining urinary tract sterility.
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23
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Purkerson JM, Schwaderer AL, Nakamori A, Schwartz GJ. Distinct α-intercalated cell morphology and its modification by acidosis define regions of the collecting duct. Am J Physiol Renal Physiol 2015; 309:F464-73. [PMID: 26084929 DOI: 10.1152/ajprenal.00161.2015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 06/12/2015] [Indexed: 01/27/2023] Open
Abstract
During metabolic acidosis, the cortical collecting duct (CCD) of the rabbit reverses the polarity of bicarbonate flux from net secretion to net absorption, and this is accomplished by increasing the proton secretory rate by α-intercalated cells (ICs) and decreasing bicarbonate secretion by β-ICs. To better characterize dynamic changes in H(+)-secreting α-ICs, we examined their morphology in collecting ducts microdissected from kidneys of normal, acidotic, and recovering rabbits. α-ICs in defined axial regions varied in number and basolateral anion exchanger (AE)1 morphology, which likely reflects their relative activity and function along the collecting duct. Upon transition from CCD to outer medullary collecting duct from the outer stripe to the inner stripe, the number of α-ICs increases from 11.0 ± 1.2 to 15.4 ± 1.11 and to 32.0 ± 1.3 cells/200 μm, respectively. In the CCD, the basolateral structure defined by AE1 typically exhibited a pyramidal or conical shape, whereas in the medulla the morphology was elongated and shallow, resulting in a more rectangular shape. Furthermore, acidosis reversibly induced α-ICs in the CCD to acquire a more rectangular morphology concomitant with a transition from diffusely cytoplasmic to increased basolateral surface distribution of AE1 and apical polarization of B1-V-ATPase. The latter results are consistent with the supposition that morphological adaptation from the pyramidal to rectangular shape reflects a transition toward a more "active" configuration. In addition, α-ICs in the outer medullary collecting duct from the outer stripe exhibited cellular morphology strikingly similar to dendritic cells that may reflect a newly defined ancillary function in immune defense of the kidney.
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Affiliation(s)
- Jeffrey M Purkerson
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - Andrew L Schwaderer
- Department of Pediatrics and Nationwide Children's Hospital, The Ohio State University, Columbus, Ohio
| | - Aya Nakamori
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
| | - George J Schwartz
- Department of Pediatrics, University of Rochester Medical Center, Rochester, New York; and
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24
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Azroyan A, Cortez-Retamozo V, Bouley R, Liberman R, Ruan YC, Kiselev E, Jacobson KA, Pittet MJ, Brown D, Breton S. Renal intercalated cells sense and mediate inflammation via the P2Y14 receptor. PLoS One 2015; 10:e0121419. [PMID: 25799465 PMCID: PMC4370445 DOI: 10.1371/journal.pone.0121419] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 02/01/2015] [Indexed: 12/31/2022] Open
Abstract
Uncontrolled inflammation is one of the leading causes of kidney failure. Pro-inflammatory responses can occur in the absence of infection, a process called sterile inflammation. Here we show that the purinergic receptor P2Y14 (GPR105) is specifically and highly expressed in collecting duct intercalated cells (ICs) and mediates sterile inflammation in the kidney. P2Y14 is activated by UDP-glucose, a damage-associated molecular pattern molecule (DAMP) released by injured cells. We found that UDP-glucose increases pro-inflammatory chemokine expression in ICs as well as MDCK-C11 cells, and UDP-glucose activates the MEK1/2-ERK1/2 pathway in MDCK-C11 cells. These effects were prevented following inhibition of P2Y14 with the small molecule PPTN. Tail vein injection of mice with UDP-glucose induced the recruitment of neutrophils to the renal medulla. This study identifies ICs as novel sensors, mediators and effectors of inflammation in the kidney via P2Y14.
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Affiliation(s)
- Anie Azroyan
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Membrane Biology/Nephrology Division, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Virna Cortez-Retamozo
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Richard Bouley
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Membrane Biology/Nephrology Division, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Rachel Liberman
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Membrane Biology/Nephrology Division, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ye Chun Ruan
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Membrane Biology/Nephrology Division, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Evgeny Kiselev
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kenneth A. Jacobson
- Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Mikael J. Pittet
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Dennis Brown
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Membrane Biology/Nephrology Division, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
| | - Sylvie Breton
- Center for Systems Biology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Membrane Biology/Nephrology Division, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts, United States of America
- * E-mail:
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25
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Ribonucleases 6 and 7 have antimicrobial function in the human and murine urinary tract. Kidney Int 2014; 87:151-61. [PMID: 25075772 PMCID: PMC4281292 DOI: 10.1038/ki.2014.268] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/23/2014] [Accepted: 06/12/2014] [Indexed: 02/06/2023]
Abstract
Recent evidence suggests antimicrobial peptides protect the urinary tract from infection. Ribonuclease 7 (RNase 7), a member of the RNase A superfamily, is a potent epithelial-derived protein that maintains human urinary tract sterility. RNase 7 expression is restricted to primates, limiting evaluation of its antimicrobial activity in vivo. Here we identified Ribonuclease 6 (RNase 6) as the RNase A Superfamily member present in humans and mice that is most conserved at the amino acid level relative to RNase 7. Like RNase 7, recombinant human and murine RNase 6 has potent antimicrobial activity against uropathogens. Quantitative real-time PCR and immunoblot analysis indicate that RNase 6 mRNA and protein are up-regulated in the human and murine urinary tract during infection. Immunostaining located RNase 6 to resident and infiltrating monocytes, macrophages, and neutrophils. Uropathogenic E. coli induces RNase 6 peptide expression in human CD14+ monocytes and murine bone marrow derived macrophages. Thus, RNase 6 is an inducible, myeloid-derived protein with markedly different expression from the epithelial-derived RNase 7 but with equally potent antimicrobial activity. Our studies suggest RNase 6 serves as an evolutionarily conserved antimicrobial peptide that participates in the maintenance of urinary tract sterility.
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26
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Paragas N, Kulkarni R, Werth M, Schmidt-Ott KM, Forster C, Deng R, Zhang Q, Singer E, Klose AD, Shen TH, Francis KP, Ray S, Vijayakumar S, Seward S, Bovino ME, Xu K, Takabe Y, Amaral FE, Mohan S, Wax R, Corbin K, Sanna-Cherchi S, Mori K, Johnson L, Nickolas T, D'Agati V, Lin CS, Qiu A, Al-Awqati Q, Ratner AJ, Barasch J. α-Intercalated cells defend the urinary system from bacterial infection. J Clin Invest 2014; 124:2963-76. [PMID: 24937428 DOI: 10.1172/jci71630] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 04/24/2014] [Indexed: 12/22/2022] Open
Abstract
α-Intercalated cells (A-ICs) within the collecting duct of the kidney are critical for acid-base homeostasis. Here, we have shown that A-ICs also serve as both sentinels and effectors in the defense against urinary infections. In a murine urinary tract infection model, A-ICs bound uropathogenic E. coli and responded by acidifying the urine and secreting the bacteriostatic protein lipocalin 2 (LCN2; also known as NGAL). A-IC-dependent LCN2 secretion required TLR4, as mice expressing an LPS-insensitive form of TLR4 expressed reduced levels of LCN2. The presence of LCN2 in urine was both necessary and sufficient to control the urinary tract infection through iron sequestration, even in the harsh condition of urine acidification. In mice lacking A-ICs, both urinary LCN2 and urinary acidification were reduced, and consequently bacterial clearance was limited. Together these results indicate that A-ICs, which are known to regulate acid-base metabolism, are also critical for urinary defense against pathogenic bacteria. They respond to both cystitis and pyelonephritis by delivering bacteriostatic chemical agents to the lower urinary system.
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27
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Lomax JE, Bianchetti CM, Chang A, Phillips GN, Fox BG, Raines RT. Functional evolution of ribonuclease inhibitor: insights from birds and reptiles. J Mol Biol 2014; 426:3041-56. [PMID: 24941155 DOI: 10.1016/j.jmb.2014.06.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 06/02/2014] [Accepted: 06/10/2014] [Indexed: 01/28/2023]
Abstract
Ribonuclease inhibitor (RI) is a conserved protein of the mammalian cytosol. RI binds with high affinity to diverse secretory ribonucleases (RNases) and inhibits their enzymatic activity. Although secretory RNases are found in all vertebrates, the existence of a non-mammalian RI has been uncertain. Here, we report on the identification and characterization of RI homologs from chicken and anole lizard. These proteins bind to RNases from multiple species but exhibit much greater affinity for their cognate RNases than for mammalian RNases. To reveal the basis for this differential affinity, we determined the crystal structure of mouse, bovine, and chicken RI·RNase complexes to a resolution of 2.20, 2.21, and 1.92Å, respectively. A combination of structural, computational, and bioinformatic analyses enabled the identification of two residues that appear to contribute to the differential affinity for RNases. We also found marked differences in oxidative instability between mammalian and non-mammalian RIs, indicating evolution toward greater oxygen sensitivity in RIs from mammalian species. Taken together, our results illuminate the structural and functional evolution of RI, along with its dynamic role in vertebrate biology.
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Affiliation(s)
- Jo E Lomax
- Graduate Program in Cellular and Molecular Biology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | | | - Aram Chang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - George N Phillips
- Department of Biochemistry and Cell Biology and Department of Chemistry, Rice University, Houston, TX 77251, USA
| | - Brian G Fox
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Ronald T Raines
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA; Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA.
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28
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Wang G. Human antimicrobial peptides and proteins. Pharmaceuticals (Basel) 2014; 7:545-94. [PMID: 24828484 PMCID: PMC4035769 DOI: 10.3390/ph7050545] [Citation(s) in RCA: 337] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/15/2014] [Accepted: 04/29/2014] [Indexed: 12/11/2022] Open
Abstract
As the key components of innate immunity, human host defense antimicrobial peptides and proteins (AMPs) play a critical role in warding off invading microbial pathogens. In addition, AMPs can possess other biological functions such as apoptosis, wound healing, and immune modulation. This article provides an overview on the identification, activity, 3D structure, and mechanism of action of human AMPs selected from the antimicrobial peptide database. Over 100 such peptides have been identified from a variety of tissues and epithelial surfaces, including skin, eyes, ears, mouths, gut, immune, nervous and urinary systems. These peptides vary from 10 to 150 amino acids with a net charge between -3 and +20 and a hydrophobic content below 60%. The sequence diversity enables human AMPs to adopt various 3D structures and to attack pathogens by different mechanisms. While α-defensin HD-6 can self-assemble on the bacterial surface into nanonets to entangle bacteria, both HNP-1 and β-defensin hBD-3 are able to block cell wall biosynthesis by binding to lipid II. Lysozyme is well-characterized to cleave bacterial cell wall polysaccharides but can also kill bacteria by a non-catalytic mechanism. The two hydrophobic domains in the long amphipathic α-helix of human cathelicidin LL-37 lays the basis for binding and disrupting the curved anionic bacterial membrane surfaces by forming pores or via the carpet model. Furthermore, dermcidin may serve as ion channel by forming a long helix-bundle structure. In addition, the C-type lectin RegIIIα can initially recognize bacterial peptidoglycans followed by pore formation in the membrane. Finally, histatin 5 and GAPDH(2-32) can enter microbial cells to exert their effects. It appears that granulysin enters cells and kills intracellular pathogens with the aid of pore-forming perforin. This arsenal of human defense proteins not only keeps us healthy but also inspires the development of a new generation of personalized medicine to combat drug-resistant superbugs, fungi, viruses, parasites, or cancer. Alternatively, multiple factors (e.g., albumin, arginine, butyrate, calcium, cyclic AMP, isoleucine, short-chain fatty acids, UV B light, vitamin D, and zinc) are able to induce the expression of antimicrobial peptides, opening new avenues to the development of anti-infectious drugs.
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Affiliation(s)
- 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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