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. 2020 Jul 4;44(3):633–638. doi: 10.1007/s12639-020-01238-0

Murine cathelicidin: as a host defensive response against Leishmania major infection

Arash Asadi 1, Amir Tavakoli Kareshk 2,✉, Iraj Sharifi 1, Nima Firouzeh 1
PMCID: PMC7410999  PMID: 32801517

Abstract

Leishmaniasis is a serious global challenge with neither efficacious prophylactic vaccine nor effective and safe therapeutic measures. Cathelicidins, members of antimicrobial peptides family, are small proteins of innate immunity system, which represent a protective barrier against a number of potential pathogens in living organisms. The murine cathelicidin or cathelin-related antimicrobial peptide (CRAMP) is expressed by a variety of cells or tissues, and highly resembles to human cathelicidin (LL-37). It is naturally expressed at a low concentration in adolescent age, but extensively increases during cutaneous infections. Despite its important role, it has less been investigated in parasitic infections. Among all cells, macrophages and skin cells are the two important cells that directly have a relationship with Leishmania major parasites. The present study aimed to show whether cathelicidins protect their hosts following cutaneous leishmaniasis due to L. major parasites. Both in vitro and in vivo models of L. major infection were established by exposing of J744 cell line (murine macrophages) and BALB/c mice with the stationary phase of L. major promastigotes for 24 h and 7 days. The findings revealed that both macrophages and skin cells significantly (p < 0.05) expressed a high level of CRAMP gene and peptide after challenging with L. major parasites. Thus, our data suggest a protective role for cathelicidins against infections caused by L. major parasites. This experimental model could be considered as a novel potential vaccine candidate for planning future control strategy against human leishmaniasis.

Keywords: Cathelicidins, Antimicrobial peptides, Cathelin-related antimicrobial peptide, Leishmaniasis, Innate immunity

Introduction

Antimicrobial peptides (AMPs) have extensively been considered to describe a large number of peptides that can provide an innate immunity barrier for their hosts (Diamond et al. 2009; Gordon et al. 2005). They serve an extensive range of functions in living organisms. Due to unique features of AMPs such antibacterial activity against a board spectrum of invasive pathogens and also participate as chemotaxis elements, these compounds extensively used in treatment of infectious diseases (Cavalcante et al. 2017; Kao et al. 2016; Mello et al. 2017; Vieira-Girao et al. 2017). Dubos (1939) successfully separated the first AMPs from a soil Bacillus strain. Up to date, over 5000 peptides of this family have been described (Zhao et al. 2013). Based on their structures, they are classified into four categories: α-defensins, β-defensins, θ-defensins and cathelicidins (Bardan et al. 2004). Cathelicidins are a major group of AMPs family which have already been identified in different numbers in every living organism (10, 11). The cathelin-related antimicrobial peptide (CRAMP), the mouse strains specific cathelicidin that commonly expresses in hematopoietic cells and epithelial cells surface (Bals and Wilson 2003; Ganz 2003; Dorschner et al. 2003; Nizet and Gallo 2003; Kosciuczuk et al. 2012). Despite its anti-parasitic effects, fewer studies have been found on CRAMP involved with parasitic infections. Owing to the high importance of cathelicidins, their protective potentials should be studied among the important parasitic diseases such as leishmaniasis. To remind, the term ‘‘leishmaniasis’’ consists of series parasitic diseases caused by intracellular agents of Leishmania genus (Shaw 1994). It is a serious concern in public health for humans and has endangered about 98 developed and developing countries of the world with more than 1 billion at-risk people (Alvar et al. 2012; Hailu et al. 2016a, b). However leishmaniasis demonstrated varied clinical manifestations but generally divided into Visceral leishmaniasis (VL), cutaneous (CL) and mucocutaneous (MCL) (Hailu et al. 2016a, b; Karimkhani et al. 2017; Novoa Juiz and Redondo Lucianez 2016). CL, the most prevalent form of leishmaniasis which comprises approximately 75% of the overall reported global cases caused by L. major and L. tropica (Quinnell and Courtenay 2009). Different species of sandflies are responsible for human and animal infections (Desjeux 1996). At present, there are neither affordable and efficacious vaccine noreffective drugs against leishmaniasis. The control of numerous reservoir hosts and biological vectors are not possible (Desjeux 1996). The only first-choice drugs, antimony compounds are not effective anymore (Tavakoli et al. 2018; Tavakoli et al. 2019; Daneshvar et al. 2017, 2018). Therefore, new natural products could potentially be a valuable source of lead molecules against leishmaniasis. Hence, the present study aimed to show whether cathelicidins protect from their hosts following cutaneous leishmaniasis (CL) due to L. major parasites.

Humans acquire infection via consuming water and food contaminated with eggs or contact with dogs.

Carnivores particularly dogs are definitive hosts in the life cycle of E. granulosus and adult worms excrete infective eggs into the environment.

Vertebrate particularly mammals acquire infection via biting of an infected female sandfly. At the first stage, the stationary phase of L. major promastigotes introduced into the skin of host. As soon as parasites inoculate, they are engulfed by macrophages where they transform into amastigote form (Handman and Bullen 2002; Schlein 1993). The amastigote forms are responsible to continue the rest of the life cycle of Leishmania parasite in sand fly vectors. Based on Leishmania life cycle, both skin and macrophage cells are considered as the most effective cells following L. major infection.

Materials and methods

Ethical approval

In this research, permission number IR.KMU.REC.1394.208 from the Ethical Review Board of Kerman University of Medical Sciences (Kerman, Iran) were received. The work was also carried out in line with the ARRIVE Guidelines for Reporting Animal Research (Kilkenny et al. 2010).

Parasite

Leishmania major promastigotes standard strain MRHO/IR/75/ER (Iranian strain) was cultured into the Roswell Park Memorial Institute medium-1640 (RPMI-1640) enriched with 10% heated fetal bovine serum (HFBS from Pastor Institute of Iran)) and 1% Penicillin/Streptomycin (Pen/Strep) antibiotics. Cultured parasites were incubated at 22 °C where slowly differentiate to metacyclic forms for the next usage.

Cell line

The Dulbecco’s Modified Eagle Medium (DMEM) (supplemented with 10% HFBS and 1% Pen/sSrep antibiotics) were used to culture J744 cell-line (murine macrophage cell-line, Pasteur Institute Tehran, Iran). The cells were maintained at 37 °C in 5% CO2.

Animals

BALB/c mice (inbred sex-age matched, 6 to 8 weeks old, weighed 20–24 g) were purchased from animal facility center of Razi Institute (Karaj, Iran). Animals were kept under appropriate conditions and handled based on standard protocols in line with the guideline of Kerman University of Medical Sciences.

In vitro model of L. major infection

Macrophages (106/well) were transferred into 24-well cell culture plates and after incubation at 37 °C for 6 h detached cells were removed by aspiration. The stationary form of L. major promastigotes (107 parasites/ml) was added to the attached-macrophages and incubated at 37 °C for 3 h; Then the free promastigotes were collected and the cells incubated at 37 °C. The infected (test) and uninfected macrophages groups (control) were incubated at 37 °C in 5% CO2 for 24 h and 7 days. After incubation, the walls contents were separately collected and centrifuged at 3000 rpm for 3 min. The supernatant fluid and cell sediments were separately collected and kept at  − 70 °C before usage.

In vivo model of L. major infection

For the experiments, 16 BALB/c mice were divided into two subgroups, test and control. The test group (n = 8 mice/group/time point) were inoculated with the stationary form of L. major promastigotes 107 parasites/ml via the subcutaneous route at the base of their tails and kept under specific conditions for 24 h and 7 days together with the untreated control group that received no parasites. Skin biopsies were taken at selected times and kept at − 70 °C until usage.

Molecular methods

RNA extraction and cDNA synthesis

RNA Purification kit (Jena Bioscience, Germany) was selected for RNA extraction from all macrophage sediments and skin biopsies at 24 h after infection. Subsequently quantified and also qualified (NanoDrop 2000 spectrophotometer Thermo Scientific, Wilmington, DE). AccuPower®RT PreMix random hexaprimer (Bioneer, Korea) used to synthesize 3 μg transcribed complementary DNA (cDNA). Briefly, 3 µg of RNA was divided in 20 µl sterile water and next added to each lyophilized tube. The flowing thermal profile was designed: 12 cycles (20 °C for30 s, 42 °C for 4 min, 55 °C for 30 s) and 95 °C for 5 min.

Conventional PCR and electrophoresis

Conventional PCR was used to check the quality of cDNA that must be applied in real-time PCR method. Briefly, the 20 μl of reaction mixture (1 μl cDNA, 9 μl master mix, 8 μl DW, 1 μl primer forward 10 Pmol, 1 μl primer reverse 10 Pmol) was prepared and applied. The thermal profile was as follow : 95 °C for 5 min, 40 cycles (95 °C for 20 s, 58 °C for 30 s, 72 °C for 30 s). The PCR products were separately run into 1% agarose gel contained ethidium-bromide dye and virtualized using Gel duck instrument.

Quantitative real-time PCR

B2M-F (5’TTCTGGTGCTTGTCTCACTGA-3’) and B2M-R (5’CAGTATGTTCGGCTTCCCATTC-3’) were used to amplify housekeeping cDNA. CRAMP-F (5’GGCTGTGGCGGTCACTAT C-3’) and CRAMP-R (5’-GTCTAGGGACTGCTGGTTGAA-3’) were applied to amplify CRAMP cDNA. In brief, 15 μl of each reaction mixture (1 μl primer forward 2.5 Pmol, 1 μl primer reverse 2.5 Pmol, 1 μl cDNA, 7 μl SYBR Green, 5 μl DW) was prepared using SYBR Premix EX Taq2 Master Mix (Takara, Japan). Rotor GENE Q (Qiagen, Germany) and specific thermal profile (95 °C for 1 min, 40 cycles (95 °C for 15 s, 58 °C for 30 s, 72 °C for 20 s) were utilized.

Protein assay by ELISA

Supernatants collected from cell culture media were directly used, while skin biopsies were homogenized first according to Ni-NTA kit (Qiagen, Germany) and then cleared lysate applied for the assessment of CRAMP using direct enzyme-linked immunosorbent assay (ELISA) on 7 days after infection. In this method, the rate of protein has a direct relationship with the absorbance of optical density (OD). Briefly, 50 µl of supernatants and cleared lysate (containing CRAMP as antigen) were separately coated into 96-well cell culture plates, blocked and washed three times with 300 µl of PBS, pH 7.2, 0.1% Tween-20. At the next step, the plate was incubated with 100 µl diluted horseradish peroxidase-conjugated CRAMP antibody (1:200, Santacruz, California) for 1 h at 37 °C and washed again. Then, the plate was incubated with 100 µl of substrate solution for 30 min. Finally, 50 µl of stop solution was added and protein concentration was measured by ELx800 microplate reader (BioTek, USA, OD492).

Statistical analysis

Our data were exhibited as mean ± SEM and their analysis was carried out using the SPSS statistical software version 17.0 (SPSS Inc., Chicago, IL, USA). Student’s t test was applied to obtain differences between the groups. Also, p < 0.05 was considered as significant level.

Results

CRAMP expression at different stages

As compatible with a described study (Dorschner et al. 2003), we found that the skin of BALB/c mice expressed a low level of CRAMP at the adult stage due the fact that skin expresses it more at newborn period (Fig. 1).

Fig. 1.

Fig. 1

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CRAMP expression at different developmental stages: skin biopsies were taken from BALB/c mice at different stages for the detection of CRAMP gene expression in 1 day mice (white bar), 4 days mice (black bar) and adult mice (blue bar). Data was exhibited as mean ± SEM and p < 0.05 was considered as significant level

CRAMP expression following Leishmania infection

Real-time PCR was used for the detection of CRAMP gene expression, and the findings were analyzed under ΔΔCT method. In J744 cell-line, the test groups expressed a significant up-regulation of CRAMP (14.2107 ± 0.1596) compared to their control (1.0033 ± 0.009754) 24 h after infection (Fig. 2a). Findings related to animal model revealed that skin at the site of parasites inoculation expressed a significant up-regulation of CRAMP (3.8730 ± 0.1895) than those in control groups (1.006 ± 0.0245) after 24 h of post-infection (Fig. 2b).

Fig. 2.

Fig. 2

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CRAMP expression in macrophages and skin cells: J744 cell-line and BALB/c mice were exposed to the stationary phase of L. major promastigotes and CRAMP expression was detected for test (white bar) and control groups (black bar) 24 h after infection. a CRAMP expression in cell culture media. b CRAMP expression in the skin of BALB/c mice. Data was shown as mean ± SEM and p ≤ 0.05 was defined as significant level

Protein assay

CRAMP gene expression occurred more in test groups; Consequently, a high concentration of CRAMP was more measured for the 7 days after infection. Based on measured protein, Leishmania-infected macrophages showed an increased level of CRAMP (1.6903 ± 0.057306) compared to control groups (0.7124 ± 0.025387) (Fig. 3a). We also observed a high release of CRAMP (0.8992 ± 0.001469) by skin cells at site of parasites inoculation relative to those in control groups (0.4447 ± 0.0159) according to the absorbance of OD assessment (Fig. 3b).

Fig. 3.

Fig. 3

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CRAMP assay: macrophagecells and BALB/c mice were exposed to the stationary phase promastigotes for 7 days. Supernatant fluid and cleared lysate prepared from cell culture media and the skin biopsies of BALB/c mice were collected from test groups (white bar) and controls (black bar) for CRAMP assay using direct ELISA method. Data was exhibited as mean ± SEM and p < 0.05 was defined as significant level

Discussion

Unlikely in nature, AMPs are an old and necessary component of innate immunity system, which find in every living thing from human to planet (DeGray et al. 2001; Zasloff 2002). They stereotypically have a wide spectrum against invasive organisms (Machado and Ottolini 2015) and provide an innate immunity inside and outside the body (Roby and Nardo 2013; Yang et al. 2015). Some cells and tissues express them (Clausen and Agner 2016). Cathelicidins are structurally different compounds known by conserved sequences (Bals and Wilson 2003). They have been identified in living organisms such as pig, mouse and human over the past decades (Agerberth et al. 1991, 1995; Gallo et al. 1997). Historically, magainin was the first anti-parasitic peptide described in parasitic fields, but other compounds were gradually discovered (Zasloff 1987, do Nascimento et al. 2015). As we know, macrophages and skin cells are the two important elements during Leishmania infection. Prior studies have revealed that these cells create the first-line immunity against leishmaniasis, which some of them have been well known. As proven, activated macrophages by interferon-gamma (IFNγ) secreted by T helper (Th)-1 can increase the expression of inducible nitric oxide (iNOS) and nitric oxide synthetase2 (NOS2) enzymes, which are necessary for the production of nitric oxide (NO) to kill intracellular parasites (Assreuy et al. 1994). Despite the presence of numerous studies at this background, some mechanisms such as AMPs have been neglected. Our study revealed that CRAMP gene is rapidly expressed by Leishmania-infected macrophages compared to intact cells (Fig. 2a). There is only one documented study at this background that has been done on human macrophage types. The data extracted from this survey shows that human macrophages type 1 express human cathelicidin or LL-37 (homologous of mouse cathelicidin or CRAMP) more than type 2 in cell media culture (Bank 2012). Another part of this work was to evaluate CRAMP expression at the site of parasite inoculation. As studies have previously shown, skin induces both physical and chemical barriers against a variety of microorganisms (Pivarcsi et al. 2005). As compatible with a previous study (Dorschner et al. 2003), we also demonstrated that CRAMP is continually expressed by skin cells in a various amount of concentrations during different developmental stages (Fig. 1a). It has been previously observed that cathelicins are induced in the skin following injury or bacterial infection (Dorschner et al. 2001). The results obtained from this survey also confirm that Leishmania infection can induce CRAMP expression in skin cells like bacterial infection (Fig. 2b). Finally, it is important to know whether CRAMP expression can be translated to its specific protein. Thus, protein assay was measured 7 days following infection. Our data revealed that host cells serve CRAMP as an immune defense response against L. major infection (Fig. 3a, b). Therefore, This experimental and preclinical model could be considered as a novel potential vaccine candidate for planning future control strategy against human leishmaniasis.

Acknowledgements

We are grateful from Kerman University of Medical Sciences, owing to finance supportive burden of this project and appreciatively the Leishmania Research Center due to use of experience and their requirements.

Authors’ contribution

All authors read and approved the final version of the manuscript.

Funding

We did not receive any grants for the publication of this study.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

To work on animals, we received permission number IR.KMU.REC.1394.208 from the Ethical Review Board of Kerman University of Medical Sciences (Kerman, Iran).

Footnotes

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

References

  1. Agerberth B, Lee JY, Bergman T, Carlquist M, Boman HG, Mutt V, et al. Amino acid sequence of PR-39. Eur J Biochem. 1991;202(3):849–854. doi: 10.1111/j.1432-1033.1991.tb16442.x. [DOI] [PubMed] [Google Scholar]
  2. Agerberth B, Gunne H, Odeberg J, Kogner P, Boman HG, Gudmundsson GH. FALL-39, a putative human peptide antibiotic, is cysteine-free and expressed in bone marrow and testis. Proc Natl Acad Sci. 1995;92(1):195–199. doi: 10.1073/pnas.92.1.195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Alvar J, Velez ID, Bern C, Herrero M, Desjeux P, Cano J, et al. Leishmaniasis worldwide and global estimates of its incidence. PLoS ONE. 2012;7(5):31. doi: 10.1371/journal.pone.0035671. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Assreuy J, Cunha FQ, Epperlein M, Noronha-Dutra A, O’Donnell CA, Liew FY, et al. Production of nitric oxide and superoxide by activated macrophages and killing of Leishmania major. Eur J Immunol. 1994;24(3):672–676. doi: 10.1002/eji.1830240328. [DOI] [PubMed] [Google Scholar]
  5. Bals R, Wilson J. Cathelicidins-a family of multifunctional antimicrobial peptides. Cell Mol Life Sci CMLS. 2003;60(4):711–720. doi: 10.1007/s00018-003-2186-9. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Bank E (2012) Leishmania major parasites and their interaction with human macrophages. Universitätsbibliothek Mainz
  7. Bardan A, Nizet V, Gallo RL. Antimicrobial peptides and the skin. Expert Opin Biol Ther. 2004;4(4):543–549. doi: 10.1517/14712598.4.4.543. [DOI] [PubMed] [Google Scholar]
  8. Cavalcante CS, Falcao CB, Fontenelle RO, Andreu D, Radis-Baptista G. Anti-fungal activity of Ctn[15-34], the C-terminal peptide fragment of crotalicidin, a rattlesnake venom gland cathelicidin. J Antibiot. 2017;70(3):231–237. doi: 10.1038/ja.2016.135. [DOI] [PubMed] [Google Scholar]
  9. Clausen ML, Agner T. Antimicrobial peptides, infections and the skin barrier. Curr Probl Dermatol. 2016;49:38–46. doi: 10.1159/000441543. [DOI] [PubMed] [Google Scholar]
  10. Daneshvar H, Sharifi I, Keyhani A, Tavakoli Kareshk A, Asadi A. Comparative analysis of antimicrobial peptides gene expression in susceptible/resistant mice macrophages to Leishmania major infection. Middle East J Fam Med. 2017;7(10):18. [Google Scholar]
  11. Daneshvar H, Tavakoli Kareshk A, SharifiI KA, Tavakoli Oliaee R, Asadi A, et al. Host-parasite responses outcome regulate the expression of antimicrobial peptide genes in the skin of BALB/c and C57BL/6 murine strains following Leishmania major MRHO/IR/75/ER infection. Iran J Parasitol. 2018;13(4):515–523. [PMC free article] [PubMed] [Google Scholar]
  12. DeGray G, Rajasekaran K, Smith F, Sanford J, Daniell H. Expression of an antimicrobial peptide via the chloroplast genome to control phytopathogenic bacteria and fungi. Plant Physiol. 2001;127(3):852–862. [PMC free article] [PubMed] [Google Scholar]
  13. Desjeux P. Leishmaniasis: public health aspects and control. Clin Dermatol. 1996;14(5):417–423. doi: 10.1016/0738-081x(96)00057-0. [DOI] [PubMed] [Google Scholar]
  14. Diamond G, Beckloff N, Weinberg A, Kisich KO. The roles of antimicrobial peptides in innate host defense. Curr Pharma Des. 2009;15(21):2377–2392. doi: 10.2174/138161209788682325. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Do Nascimento VV, Mello ÉO, Carvalho LP, de Melo EJ, Carvalho AO, Fernandes KV, et al. PvD1 defensin, a plant antimicrobial peptide with inhibitory activity against Leishmania amazonensis. Biosci Rep. 2015;35(5):e00248. doi: 10.1042/BSR20150060. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Dorschner RA, Pestonjamasp VK, Tamakuwala S, Ohtake T, Rudisill J, Nizet V, et al. Cutaneous injury induces the release of cathelicidin anti-microbial peptides active against group A Streptococcus. J Investig Dermatol. 2001;117(1):91–97. doi: 10.1046/j.1523-1747.2001.01340.x. [DOI] [PubMed] [Google Scholar]
  17. Dorschner RA, Lin KH, Murakami M, Gallo RL. Neonatal skin in mice and humans expresses increased levels of antimicrobial peptides: innate immunity during development of the adaptive response. Pediatr Res. 2003;53(4):566–572. doi: 10.1203/01.PDR.0000057205.64451.B7. [DOI] [PubMed] [Google Scholar]
  18. Dubos RJ. Studies on a bactericidal agent extracted from a soil bacillus: I. Preparation of the agent. Its activity in vitro. J Exp Med. 1939;70(1):1. doi: 10.1084/jem.70.1.1. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Gallo RL, Kim KJ, Bernfield M, Kozak CA, Zanetti M, Merluzzi L, et al. Identification of CRAMP, a cathelin-related antimicrobial peptide expressed in the embryonic and adult mouse. J Biol Chem. 1997;272(20):13088–13093. doi: 10.1074/jbc.272.20.13088. [DOI] [PubMed] [Google Scholar]
  20. Ganz T. Defensins: antimicrobial peptides of innate immunity. Nat Rev Immunol. 2003;3(9):710–720. doi: 10.1038/nri1180. [DOI] [PubMed] [Google Scholar]
  21. Gordon YJ, Romanowski EG, McDermott AM. A review of antimicrobial peptides and their therapeutic potential as anti-infective drugs. Curr Eye Res. 2005;30(7):505–515. doi: 10.1080/02713680590968637. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Hailu A, Dagne DA, Boelaert M (2016a) Leishmaniasis. Negl Trop Dis-Sub-Saharan Africa. Springer, pp 87–112
  23. Hailu T, Yimer M, Mulu W, Abera B. Challenges in visceral leishmaniasis control and elimination in the developing countries: a review. J Vector Borne Dis. 2016;53(3):193–198. [PubMed] [Google Scholar]
  24. Handman E, Bullen DV. Interaction of Leishmania with the host macrophage. Trends Parasitol. 2002;18(8):332–334. doi: 10.1016/s1471-4922(02)02352-8. [DOI] [PubMed] [Google Scholar]
  25. Kao C, Lin X, Yi G, Zhang Y, Rowe-Magnus DA, Bush K. Cathelicidin antimicrobial peptides with reduced activation of toll-like receptor signaling have potent bactericidal activity against colistin-resistant bacteria. MBio. 2016;7(5):01418-16. doi: 10.1128/mBio.01418-16. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Karimkhani C, Wanga V, Naghavi P, Dellavalle RP, Naghavi M. Global burden of cutaneous leishmaniasis. Lancet Infect Dis. 2017;17(3):264. doi: 10.1016/s1473-3099(16)30217-1. [DOI] [PubMed] [Google Scholar]
  27. Kilkenny C, Browne WJ, Cuthill IC, Emerson M, Altman DG. Improving bioscience research reporting: the ARRIVE guidelines for reporting animal research. PLoS Biol. 2010;8(6):e1000412. doi: 10.1371/journal.pbio.1000412. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Kosciuczuk EM, Lisowski P, Jarczak J, Strzalkowska N, Jozwik A, Horbanczuk J, et al. Cathelicidins: family of antimicrobial peptides: a review. Mol Biol Rep. 2012;39(12):10957–10970. doi: 10.1007/s11033-012-1997-x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Machado LR, Ottolini B. An evolutionary history of defensins: a role for copy number variation in maximizing host innate and adaptive immune responses. Front Immunol. 2015;6:115. doi: 10.3389/fimmu.2015.00115. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Mello CP, Lima DB, Menezes RR, Bandeira IC, Tessarolo LD, Sampaio TL, et al. Evaluation of the antichagasic activity of batroxicidin, a cathelicidin-related antimicrobial peptide found in Bothrops atrox venom gland. Toxicon. 2017;130:56–62. doi: 10.1016/j.toxicon.2017.02.031. [DOI] [PubMed] [Google Scholar]
  31. Nizet V, Gallo RL. Cathelicidins and innate defense against invasive bacterial infection. Scand J Infect Dis. 2003;35(9):670–676. doi: 10.1080/00365540310015629. [DOI] [PubMed] [Google Scholar]
  32. Novoa Juiz V, Redondo Lucianez R. Mucocutaneous leishmaniasis. Acta Otorrinolaringol Esp. 2016;67(6):16. doi: 10.1016/j.otorri.2015.11.004. [DOI] [PubMed] [Google Scholar]
  33. Pivarcsi A, Nagy I, Kemeny L. Innate immunity in the skin: how keratinocytes fight against pathogens. Curr Immunol Rev. 2005;1(1):29–42. [Google Scholar]
  34. Quinnell RJ, Courtenay O. Transmission, reservoir hosts and control of zoonotic visceral leishmaniasis. Parasitology. 2009;136(14):1915–1934. doi: 10.1017/S0031182009991156. [DOI] [PubMed] [Google Scholar]
  35. Roby KD, Nardo AD. Innate immunity and the role of the antimicrobial peptide cathelicidin in inflammatory skin disease. Drug Discov Today Dis Mech. 2013;10(3–4):e79–e82. doi: 10.1016/j.ddmec.2013.01.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Schlein Y. Leishmania and sandflies: interactions in the life cycle and transmission. Parasitol Today. 1993;9(7):255–258. doi: 10.1016/0169-4758(93)90070-v. [DOI] [PubMed] [Google Scholar]
  37. Shaw JJ. Taxonomy of the genus Leishmania: present and future trends and their implications. Memórias do Instituto Oswaldo Cruz. 1994;89(3):471–478. doi: 10.1590/s0074-02761994000300033. [DOI] [PubMed] [Google Scholar]
  38. Tavakoli OR, Sharifi I, Afkar A, Tavakoli Kareshk A, Asadi A, et al. Unresponsiveness to meglumine antimoniate in anthroponotic cutaneous leishmaniasis field isolates: analysis of resistance biomarkers by gene expression profiling. Trop Med Int Health. 2018;23(6):622–633. doi: 10.1111/tmi.13062. [DOI] [PubMed] [Google Scholar]
  39. Tavakoli OR, Sharifi I, Afkar A, Jafarzadeh A, Tavakoli Kareshk A, et al. Differential expression of TLRs 2, 4, 9, iNOS and TNF-α and arginase activity in peripheral blood monocytes from glucantime unresponsive and responsive patients with anthroponotic cutaneous leishmaniasis caused by Leishmania tropica. Microb Pathog. 2019;126:368–378. doi: 10.1016/j.micpath.2018.11.004. [DOI] [PubMed] [Google Scholar]
  40. Vieira-Girao PR, Falcao CB, Rocha IR, Lucena HM, Costa FH, Radis-Baptista G. Antiviral activity of Ctn[15-34], a cathelicidin-derived eicosapeptide, against infectious myonecrosis virus in litopenaeus vannamei primary hemocyte cultures. Food Environ Virol. 2017;16(10):017–9285. doi: 10.1007/s12560-017-9285-5. [DOI] [PubMed] [Google Scholar]
  41. Yang YM, Guo YF, Zhang HS, Sun TY. Antimicrobial peptide LL-37 circulating levels in chronic obstructive pulmonary disease patients with high risk of frequent exacerbations. J Thorac Dis. 2015;7(4):740–745. doi: 10.3978/j.issn.2072-1439.2015.04.33. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Zasloff M. Magainins, a class of antimicrobial peptides from Xenopus skin: isolation, characterization of two active forms, and partial cDNA sequence of a precursor. Proc Natl Acad Sci. 1987;84(15):5449–5453. doi: 10.1073/pnas.84.15.5449. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Zasloff M. Antimicrobial peptides of multicellular organisms. Nature. 2002;415(6870):389–395. doi: 10.1038/415389a. [DOI] [PubMed] [Google Scholar]
  44. Zhao X, Wu H, Lu H, Li G, Huang Q. LAMP: a database linking antimicrobial peptides. PLoS ONE. 2013;8(6):e66557. doi: 10.1371/journal.pone.0066557. [DOI] [PMC free article] [PubMed] [Google Scholar]

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