| 1. |
- Jena, Prajna, et al.
(författare)
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Azurophil Granule Proteins Constitute the Major Mycobactericidal Proteins in Human Neutrophils and Enhance the Killing of Mycobacteria in Macrophages
- 2012
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:12
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Tidskriftsartikel (refereegranskat)abstract
- Pathogenic mycobacteria reside in, and are in turn controlled by, macrophages. However, emerging data suggest that neutrophils also play a critical role in innate immunity to tuberculosis, presumably by their different antibacterial granule proteins. In this study, we purified neutrophil azurophil and specific granules and systematically analyzed the antimycobacterial activity of some purified azurophil and specific granule proteins against M. smegmatis, M. bovis-BCG and M. tuberculosis H37Rv. Using gel overlay and colony forming unit assays we showed that the defensin-depleted azurophil granule proteins (AZP) were more active against mycobacteria compared to other granule proteins and cytosolic proteins. The proteins showing antimycobacterial activity were identified by MALDI-TOF mass spectrometry. Electron microscopic studies demonstrate that the AZP disintegrate bacterial cell membrane resulting in killing of mycobacteria. Exogenous addition of AZP to murine macrophage RAW 264.7, THP-1 and peripheral blood monocyte-derived macrophages significantly reduced the intracellular survival of mycobacteria without exhibiting cytotoxic activity on macrophages. Immunofluorescence studies showed that macrophages actively endocytose neutrophil granular proteins. Treatment with AZP resulted in increase in co-localization of BCG containing phagosomes with lysosomes but not in increase of autophagy. These data demonstrate that neutrophil azurophil proteins may play an important role in controlling intracellular survival of mycobacteria in macrophages. Citation: Jena P, Mohanty S, Mohanty T, Kallert S, Morgelin M, et al. (2012) Azurophil Granule Proteins Constitute the Major Mycobactericidal Proteins in Human Neutrophils and Enhance the Killing of Mycobacteria in Macrophages. PLoS ONE 7(12): e50345. doi:10.1371/journal.pone.0050345
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| 2. |
- Fan, Yanmiao, et al.
(författare)
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Dendritic Hydrogels Induce Immune Modulation in Human Keratinocytes and Effectively Eradicate Bacterial Pathogens
- 2021
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Ingår i: Journal of the American Chemical Society. - : American Chemical Society (ACS). - 0002-7863 .- 1520-5126. ; 143:41, s. 17180-17190
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Tidskriftsartikel (refereegranskat)abstract
- Infections caused by antibiotic-resistant bacteria are globally a major threat, leading to high mortality rates and increased economic burden. Novel treatment strategies are therefore urgently needed by healthcare providers to protect people. Biomaterials that have inherent antibacterial properties and do not require the use of antibiotics present an attractive and feasible avenue to achieve this goal. Herein, we demonstrate the effect of a new class of cationic hydrogels based on amino-functional hyperbranched dendritic-linear-dendritic copolymers (HBDLDs) exhibiting excellent antimicrobial activity toward a wide range of clinical Gram-positive and Gram-negative bacteria, including drug-resistant strains isolated from wounds. Intriguingly, the hydrogels can induce the expression of the antimicrobial peptides RNase 7 and psoriasin, promoting host-mediated bacterial killing in human keratinocytes (HaCaT). Moreover, treatment with the hydrogels decreased the proinflammatory cytokine IL-1 beta, reactive nitrogen species (NO), and mitochondrial reactive oxygen species (ROS) in S. aureus-infected HaCaT cells, conjunctively resulting in reduced inflammation.
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| 3. |
- Fan, Yanmiao, et al.
(författare)
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Nanogel encapsulated hydrogels as advanced wound dressings for the controlled delivery of antibiotics
- 2021
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Ingår i: Advanced Functional Materials. - : Wiley. - 1616-301X .- 1616-3028. ; 31
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Tidskriftsartikel (refereegranskat)abstract
- Biocompatible and degradable dual-delivery gel systems based on hyperbrancheddendritic−linear−dendritic copolymers (HBDLDs) is herein conceptualizedand accomplished via thiol-ene click chemistry. The elasticity of thehydrogels is tunable by varying the lengths of PEG (2, 6, 10 kDa) or the dryweight percentages (20, 30, 40 wt%), and are found to be between 2–14.7 kPa,comparable to human skin. The co-delivery of antibiotics is achieved, wherethe hydrophilic drug novobiocin sodium salt (NB) is entrapped within thehydrophilic hydrogel, while the hydrophobic antibiotic ciprofloxacin (CIP) isencapsulated within the dendritic nanogels (DNGs) with hydrophobic cores(DNGs-CIP). The DNGs-CIP with drug loading capacity of 2.83 wt% are thenphysically entrapped within the hybrid hydrogels through UV curing. Thehybrid hydrogels enabled the quick release of NB and prolonged released ofCIP. In vitro cell infection assays showed that the antibiotic-loaded hybridhydrogels are able to treat bacterial infections with significant bacterialreduction. Hybrid hydrogel band aids are fabricated and exhibited betterantibacterial activity compared with commercial antimicrobial band aids.Remarkably, most hydrogels and hybrid hydrogels showed enhanced humandermal cell proliferation and could be degraded into non-toxic constituents,showing great promise as wound dressing materials.
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| 4. |
- Fan, Yanmiao, et al.
(författare)
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Scalable Dendritic Hydrogels Targeting Drug-Resistant Skin Pathogens and the Immunomodulation Activity in Keratinocytes
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Microbial infections caused by antibiotic-resistant bacteria are a major threat to humans, associated with a high mortality and for the society increased economic burden. To address this, a series of cationic hydrogels based on amino-functional hyperbranched dendritic−linear−dendritic copolymers (HBDLDs) were formed easily within 1 min through interactions between the amino-terminated HBDLDs and di(N-hydroxysuccinimide ester) functionalized polyethylene glycol (PEG). The hydrogels exhibited excellent inherent antimicrobial activity towards a wide range of Gram-positive and Gram-negative clinical bacteria including drug-resistant strains, isolated from wounds. In vitro cell infection assays showed that the hydrogels were able to significantly reduce cell infections caused by different strains, with the highest killing efficacy of 96% towards S. aureus. The hydrogels also inhibited the initiation of E. coli biofilm formation. Remarkably, the hydrogels induced the expression of the antimicrobial peptides, RNase 7 and psoriasin, in keratinocytes (HaCaT) which suggests that the hydrogels are likely able to promote host-mediated bacterial killing. The expression of pro-inflammatory cytokine IL-1β, reactive nitrogen species (NO) and mitochondrial reactive oxygen species (ROS) in S. aureus-infected HaCaT cells were reduced after the treatment with the hydrogels. The hydrogels degraded within 24 h, showing great promise for treating skin infections and reducing inflammation.
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| 5. |
- Kerr White, John, et al.
(författare)
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A Synthetic Cyclized Antimicrobial Peptide with Potent Effects against Drug-Resistant Skin Pathogens
- 2023
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Ingår i: ACS - Infectious Diseases. - : American Chemical Society (ACS). - 2373-8227. ; 9:5, s. 1056-1063
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Tidskriftsartikel (refereegranskat)abstract
- Dermal infections requiring treatment are usually treated with conventional antibiotics, but the rise of bacterial resistance to first-line antibiotics warrants alternative therapeutics. Here, we report that a backbone-cyclized antimicrobial peptide, CD4-PP, designed from the human host defense peptide LL-37, has strong direct antibacterial effects on antibiotic sensitive as well as resistant-type strains and clinical isolates of common skin pathogens in the low (<2) μM range. In addition, it influences innate immunity in keratinocytes, and treatment with CD4-PP is able to clear bacterial infections in infected keratinocytes. Additionally, CD4-PP treatment significantly reduces the wound area in a lawn of keratinocytes infected with MRSA. In conclusion, CD4-PP has the potential to serve as a future drug treating wounds infected with antibiotic-resistant bacteria.
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| 6. |
- Li, Fengyang, et al.
(författare)
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Patatin-like phospholipase CapV in Escherichia coli-morphological and physiological effects of one amino acid substitution
- 2022
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Ingår i: npj Biofilms and Microbiomes. - : Springer Science and Business Media LLC. - 2055-5008. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- In rod-shaped bacteria, morphological plasticity occurs in response to stress, which blocks cell division to promote filamentation. We demonstrate here that overexpression of the patatin-like phospholipase variant CapV(Q329R), but not CapV, causes pronounced sulA-independent pyridoxine-inhibited cell filamentation in the Escherichia coli K-12-derivative MG1655 associated with restriction of flagella production and swimming motility. Conserved amino acids in canonical patatin-like phospholipase A motifs, but not the nucleophilic serine, are required to mediate CapV(Q329R) phenotypes. Furthermore, CapV(Q329R) production substantially alters the lipidome and colony morphotype including rdar biofilm formation with modulation of the production of the biofilm activator CsgD, and affects additional bacterial traits such as the efficiency of phage infection and antimicrobial susceptibility. Moreover, genetically diverse commensal and pathogenic E. coli strains and Salmonella typhimurium responded with cell filamentation and modulation in colony morphotype formation to CapV(Q329R) expression. In conclusion, this work identifies the CapV variant CapV(Q329R) as a pleiotropic regulator, emphasizes a scaffold function for patatin-like phospholipases, and highlights the impact of the substitution of a single conserved amino acid for protein functionality and alteration of host physiology.
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| 7. |
- Mohanty, Soumitra, et al.
(författare)
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A mycobacterial phosphoribosyltransferase promotes bacillary survival by inhibiting oxidative stress and autophagy pathways in macrophages and zebrafish.
- 2015
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Ingår i: Journal of Biological Chemistry. - 1083-351X. ; 290:21, s. 13321-13343
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Tidskriftsartikel (refereegranskat)abstract
- Mycobacterium tuberculosis (Mtb) employs various strategies to modulate host immune responses to facilitate its persistence in macrophages. The Mtb cell wall contains numerous glycoproteins with unknown role in pathogenesis. Here, by using concavalinA and LC-MS analysis we identified a novel mannosylated glycoprotein phosphoribosyl- transferase, encoded by the Rv3242c, from Mtb cell walls. Homology modeling, bioinformatic analyses and assay of phosphoribosyltransferase activity measurement in Mycobacterium smegmatis expressing recombinant Rv3242c (MsmRv3242c) confirmed the mass spectrometry data. Using Mycobacterium marinum-zebrafish and the surrogate MsmRv3242c infection models, we proved that phosphoribosyltransferase is involved in mycobacterial virulence. Histological and infection assays showed that M. marinum mimG mutant, an Rv3242c orthologue in a pathogenic M. marinum strain, was strongly attenuated in adult zebrafish and also survived less in macrophages. In contrast, infection with wild-type and the complemented ∆mimG:Rv3242c M. marinum strains showed prominent pathological features such as severe emaciation, skin lesions, hemorrhaging, and more zebrafish death. Similarly, recombinant MsmRv3242c bacteria showed increased invasion in non-phagocytic epithelial cells and longer intracellular survival in macrophages as compared to wild-type and vector control M. smegmatis strains. Further mechanistic studies revealed that the Rv3242c and mimG mediated enhancement of intramacrophagic survival was due to inhibition of autophagy, reactive oxygen species and reduced activities of superoxide dismutase and catalase enzymes. Infection with MsmRv3242c also activated the MAPK pathway, NF-κB and inflammatory cytokines. In summary, we show that a novel mycobacterial mannosylated phosphoribosyltransferase acts as a virulence and immunomodulatory factors, suggesting that it may constitute a novel target for antimycobacterial drugs.
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| 8. |
- Mohanty, Soumitra, et al.
(författare)
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Diabetes downregulates the antimicrobial peptide psoriasin and increases E. coli burden in the urinary bladder
- 2022
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 13
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Tidskriftsartikel (refereegranskat)abstract
- Diabetes is known to increase susceptibility to infections, partly due to impaired granulocyte function and changes in the innate immunity. Here, we investigate the effect of diabetes, and high glucose on the expression of the antimicrobial peptide, psoriasin and the putative consequences for E. coli urinary tract infection. Blood, urine, and urine exfoliated cells from patients are studied. The influence of glucose and insulin is examined during hyperglycemic clamps in individuals with prediabetes and in euglycemic hyperinsulinemic clamped patients with type 1 diabetes. Important findings are confirmed in vivo in type 2 diabetic mice and verified in human uroepithelial cell lines. High glucose concentrations induce lower psoriasin levels and impair epithelial barrier function together with altering cell membrane proteins and cytoskeletal elements, resulting in increasing bacterial burden. Estradiol treatment restores the cellular function with increasing psoriasin and bacterial killing in uroepithelial cells, confirming its importance during urinary tract infection in hyperglycemia. In conclusion, our findings present the effects and underlying mechanisms of high glucose compromising innate immunity. Patients with diabetes have an increased susceptibility to infections. Here the authors show that high glucose impairs innate immunity through reduced levels of the antimicrobial peptide psoriasin and impaired epithelial barrier function, resulting in an increased risk of urinary tract infection.
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| 9. |
- Mohanty, Soumitra, et al.
(författare)
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Inhibition of COX-2 signaling favors E. coli during urinary tract infection
- 2023
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Ingår i: Journal of Inflammation. - : BioMed Central (BMC). - 1476-9255. ; 20:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: To avoid the overuse of antibiotics, non-steroidal anti-inflammatory drugs (NSAIDs), acting via cyclooxygenase (COX) inhibition, have been used to reduce pain and as an alternative treatment for uncomplicated urinary tract infections (UTIs). However, clinical studies evaluating NSAIDs versus antibiotics have reported an increased risk of acute pyelonephritis. Therefore, we hypothesized that COX inhibition could compromise the innate immune response and contribute to complications in patients with uncomplicated UTI.Results: We here demonstrate that in particular COX-2 inhibition led to decreased expression of the antimicrobial peptides psoriasin and human β-defensin-2 in human uroepithelial cells. Psoriasin expression was altered in neutrophils and macrophages. COX-2 inhibition also had impact on the inflammasome mediated IL-1β expression in response to uroepithelial E. coli infection. Further, COX-2 inhibition downregulated free radicals and the epithelial barrier protein claudin 1, favoring infectivity. In addition, conditioned media from COX-2 inhibited uroepithelial cells infected with E. coli failed to activate macrophages.Conclusions: Taken together, our data suggests an adverse innate immune effect of COX-2 inhibition on uroepithelial cells during UTI.
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| 10. |
- White, John Kerr, et al.
(författare)
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A stable cyclized antimicrobial peptide derived from LL-37 with host immunomodulatory effects and activity against uropathogens
- 2022
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Ingår i: Cellular and Molecular Life Sciences (CMLS). - : Springer Nature. - 1420-682X .- 1420-9071. ; 79:8
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Tidskriftsartikel (refereegranskat)abstract
- The increasing antibiotic resistance among uropathogenic bacteria warrants alternative therapeutic strategies. We demonstrate the potential of the synthetic peptide CD4-PP, designed by dimerization and backbone cyclization of the shortest antimicrobial region of human cathelicidin, LL-37. CD4-PP is active against clinical and type strains of common uropathogens Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa at concentrations substantially below cellular cytotoxic levels and induced membrane deformation and leakage in E. coli and P. aeruginosa. Furthermore, CD4-PP treatment prevented the formation of new biofilm and dissolved mature biofilm created by E. coli and P. aeruginosa and targeted curli amyloid in E. coli biofilms. In addition, CD4-PP also induced production of LL-37 by uroepithelial cells and increased the expression of tight junction proteins claudin-14 and occludin. During uroepithelial cell infection, CD4-PP significantly reduced uropathogen survival when treatment was given at the start of infection. Low micromolar of CD4-PP treatment initiated after 2 h was successful with all tested species, except P. aeruginosa where CD4-PP was unable to reduce survival, which could be attributed by early biofilm formation. Finally, we demonstrated that urinary catheter pieces coated with saline fluid supplemented with CD4-PP reduced the attachment of E. coli, giving it a potential clinical application.
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