scholarly journals Novel Assay To Characterize Neutrophil Responses to Oral Biofilms

2018 ◽  
Vol 87 (2) ◽  
Author(s):  
Morvarid Oveisi ◽  
Harold Shifman ◽  
Noah Fine ◽  
Chunxiang Sun ◽  
Naomi Glogauer ◽  
...  

ABSTRACTNeutrophils, the most numerous leukocytes, play an important role in maintaining oral health through interactions with oral microbial biofilms. Both neutrophil hyperactivity and the bacterial subversion of neutrophil responses can cause inflammation-mediated tissue damage like that seen in periodontal disease. We describe here an assay that assesses neutrophil activation responses to monospecies biofilm bacteriain vitrobased on the surface expression of cluster of differentiation (CD) markers associated with various neutrophil functions. Most of what we know about neutrophil responses to bacteria is based onin vitroassays that use planktonic bacteria and isolated/preactivated neutrophils, which makes interpretation of the neutrophil responses to bacteria a challenge. An understanding of how neutrophils differentially interact with and respond to commensal and pathogenic oral bacteria is necessary in order to further understand the neutrophil’s role in maintaining oral health and the pathogenesis of periodontal disease. In this study, a flow cytometry-basedin vitroassay was developed to characterize neutrophil activation states based on CD marker expressions in response to oral monospecies bacterial biofilms. Using this approach, changes in CD marker expressions in response to specific prominent oral commensal and pathogenic bacteria were assayed. Several functional assays, including assays for phagocytosis, production of reactive oxygen species, activation of the transcription factor Nrf2, neutrophil extracellular trap formation, and myeloperoxidase release, were also performed to correlate neutrophil function with CD marker expression. Our results demonstrate that neutrophils display bacterial species-specific responses. This assay can be used to characterize how specific biofilms alter specific neutrophil pathways associated with their activation.

2020 ◽  
Vol 16 (1) ◽  
Author(s):  
Eva Cunha ◽  
Sandra Rebelo ◽  
Carla Carneiro ◽  
Luís Tavares ◽  
Luís Miguel Carreira ◽  
...  

Abstract Background Periodontal disease (PD) in dogs is prompted by the establishment of a polymicrobial biofilm at the tooth surface and a subsequent host inflammatory response. Several strategies may be used for PD control, including dental hygiene home care procedures, like toothbrushing, special diet and chew toys that reduce dental plaque accumulation, or professional periodontal treatments. Aiming at PD control, a biogel composed by nisin and guar-gum was previously developed. This work aimed to establish an in vitro model mimicking the PD-associated biofilms and to evaluate the nisin-biogel inhibitory activity against this polymicrobial biofilm by determining its Minimum Biofilm Inhibitory (MBIC) and Eradication Concentrations (MBEC). Bacterial species tested included Neisseria zoodegmatis CCUG 52598T, Corynebacterium canis CCUG 58627T, Porphyromonas cangingivalis DSMZ VPB 4874, Peptostreptococcus canis CCUG 57081 and an Enterococcus faecalis isolate belonging to a collection of oral bacteria obtained from dogs with PD. Before establishing the biofilm, coaggregation between species was determined by optical density measurement after 2 and 24 hours. Nisin-biogel MBIC and MBEC values regarding the polymicrobial biofilm were determined using a modified version of the Calgary biofilm pin lid device, after confirming the presence of the five bacterial species by Fluorescent In Situ Hybridization. Results Only 40% of the bacterial dual suspensions were able to coaggregate at 2 hours, but all species tested exhibited a coaggregation percentage higher than 30% at 24 hours. It was possible to establish a 48 h polymicrobial biofilm model composed by the five bacterial species selected. This model was used to determine nisin-biogel MBIC (26.39 ± 5.89 µg/mL) and MBEC (62.5 ± 27.73 µg/mL) values. Conclusions Our results showed that the nisin-biogel can inhibit and eradicate PD multispecies biofilms. As this in vitro model mimics an in vivo periodontal polymicrobial biofilm, our results reinforce the potential of the application of nisin-biogel for canine PD control.


2016 ◽  
Vol 95 (13) ◽  
pp. 1487-1493 ◽  
Author(s):  
N. Hirose ◽  
R. Kitagawa ◽  
H. Kitagawa ◽  
H. Maezono ◽  
A. Mine ◽  
...  

An experimental cavity disinfectant (ACC) that is intended to be used for various direct and indirect restorations was prepared by adding an antibacterial monomer 12-methacryloyloxydodecylpyridinum bromide (MDPB) at 5% into 80% ethanol. The antibacterial effectiveness of ACC and its influences on the bonding abilities of resin cements were investigated. To examine the antibacterial activity of unpolymerized MDPB, the minimum inhibitory and bactericidal concentrations (MIC and MBC) were determined for Streptococcus mutans, Lactobacillus casei, Actinomyces naeslundii, Parvimonas micra, Enterococcus faecalis, Fusobacterium nucleatum, and Porphyromonas gingivalis. Antibacterial activities of ACC and the commercial cavity disinfectant containing 2% chlorhexidine and ethanol (CPS) were evaluated by agar disk diffusion tests through 7 bacterial species and by MIC and MBC measurement for S. mutans. The effects of ACC and CPS to kill bacteria in dentinal tubules were compared with an S. mutans–infected dentin model. Shear bond strength tests were used to examine the influences of ACC on the dentin-bonding abilities of a self-adhesive resin cement and a dual-cure resin cement used with a primer. Unpolymerized MDPB showed strong antibacterial activity against 7 oral bacteria. ACC produced inhibition zones against all bacterial species similar to CPS. For ACC and CPS, the MIC value for S. mutans was identical, and the MBC was similar with only a 1-step dilution difference (1:2). Treatment of infected dentin with ACC resulted in significantly greater bactericidal effects than CPS ( P < 0.05, analysis of variance and Tukey’s honest significant difference test). ACC showed no negative influences on the bonding abilities to dentin for both resin cements, while CPS reduced the bond strength of the self-adhesive resin cement ( P < 0.05). This study clarified that the experimental cavity disinfectant containing 5% MDPB is more effective in vitro than the commercially available chlorhexidine solution to eradicate bacteria in dentin, without causing any adverse influences on the bonding abilities of resinous luting cements.


2020 ◽  
Vol 110 (5) ◽  
pp. 989-998
Author(s):  
Cláudio M. Vrisman ◽  
Loïc Deblais ◽  
Yosra A. Helmy ◽  
Reed Johnson ◽  
Gireesh Rajashekara ◽  
...  

Plant pathogenic bacteria in the genus Erwinia cause economically important diseases, including bacterial wilt of cucurbits caused by Erwinia tracheiphila. Conventional bactericides are insufficient to control this disease. Using high-throughput screening, 464 small molecules (SMs) with either cidal or static activity at 100 µM against a cucumber strain of E. tracheiphila were identified. Among them, 20 SMs (SM1 to SM20), composed of nine distinct chemical moiety structures, were cidal to multiple E. tracheiphila strains at 100 µM. These lead SMs had low toxicity to human cells and honey bees at 100 µM. No phytotoxicity was observed on melon plants at 100 µM, except when SM12 was either mixed with Silwet L-77 and foliar sprayed or when delivered through the roots. Lead SMs did not inhibit the growth of beneficial Pseudomonas and Enterobacter species but inhibited the growth of Bacillus species. Nineteen SMs were cidal to Xanthomonas cucurbitae and showed >50% growth inhibition against Pseudomonas syringae pv. lachrymans. In addition, 19 SMs were cidal or static against Erwinia amylovora in vitro. Five SMs demonstrated potential to suppress E. tracheiphila when foliar sprayed on melon plants at 2× the minimum bactericidal concentration. Thirteen SMs reduced Et load in melon plants when delivered via roots. Temperature and light did not affect the activity of SMs. In vitro cidal activity was observed after 3 to 10 h of exposure to these five SMs. Here, we report 19 SMs that provide chemical scaffolds for future development of bactericides against plant pathogenic bacterial species.


2019 ◽  
Vol 10 (2) ◽  
pp. 1049-1053 ◽  
Author(s):  
Geetha RV ◽  
John Rozar Raj B ◽  
Lakshmi Thangavelu

To conduct a study regarding the antibacterial activity of essential oils against bacteria causing Caries. Essential oils are distillates of the volatile compounds of a plant’s secondary metabolism and may act as photoprotective agents. Their curative effect has been known since antiquity. It is based on a variety of pharmacological properties which are specific for each plant species. The mouth contains a variety of oral bacteria, but only a few species of bacteria are believed to cause dental caries. Antibacterial activity of the three essential oils, Rosemary oil, Holy basil oil, Thyme oil was screened against Streptococcus mutans, using disc diffusion technique. The rosemary oil was more effective against Streptococcus mutans with a zone of inhibition of 52 mm diameter (at concentration 200 µl), Rosemary oil showed a zone of inhibition of 44 mm diameter and with thyme oil, the zone diameter was 30 mm. The results of this study showed that the essential oils at different concentrations exhibited antibacterial activity against the bacterial species tested.


2017 ◽  
Vol 1 (11) ◽  
pp. 662-668 ◽  
Author(s):  
Yuyan Shen ◽  
Hong Hong ◽  
Panjamaporn Sangwung ◽  
Stephanie Lapping ◽  
Lalitha Nayak ◽  
...  

Key Points KLF4 deficiency impairs neutrophil function in vitro and in vivo. This is the first demonstration that KLF4 plays a crucial role in neutrophils.


2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Bishnu P. Marasini ◽  
Pankaj Baral ◽  
Pratibha Aryal ◽  
Kashi R. Ghimire ◽  
Sanjiv Neupane ◽  
...  

The worldwide increase of multidrug resistance in both community- and health-care associated bacterial infections has impaired the current antimicrobial therapy, warranting the search for other alternatives. We aimed to find thein vitroantibacterial activity of ethanolic extracts of 16 different traditionally used medicinal plants of Nepal against 13 clinical and 2 reference bacterial species using microbroth dilution method. The evaluated plants species were found to exert a range ofin vitrogrowth inhibitory action against the tested bacterial species, andCynodon dactylonwas found to exhibit moderate inhibitory action against 13 bacterial species including methicillin-resistantStaphylococcus aureus, imipenem-resistantPseudomonas aeruginosa, multidrug-resistantSalmonella typhi, andS. typhimurium. The minimum inhibitory concentration (MIC) values of tested ethanolic extracts were found from 31 to >25,000 μg/mL. Notably, ethanolic extracts ofCinnamomum camphora, Curculigo orchioides, andCurcuma longaexhibited the highest antibacterial activity againstS. pyogeneswith a MIC of 49, 49, and 195 μg/mL, respectively; whereas chloroform fraction ofCynodon dactylonexhibited best antibacterial activity againstS. aureuswith a MIC of 31 μg/mL. Among all,C. dactylon, C. camphora, C. orchioides, andC. longaplant extracts displayed a potential antibacterial activity of MIC < 100 μg/mL.


2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
León Francisco Espinosa-Cristóbal ◽  
Carolina Holguín-Meráz ◽  
Erasto Armando Zaragoza-Contreras ◽  
Rita Elizabeth Martínez-Martínez ◽  
Alejandro Donohue-Cornejo ◽  
...  

The dental plaque is an oral microbiome hardly associated to be the etiological agent of dental caries and periodontal disease which are still considered serious health public problems. Silver nanoparticles (AgNPs) have demonstrated to have good antimicrobial properties affecting a wide variety of microorganisms, including oral bacteria; however, there is no scientific information that has evaluated the antimicrobial effect of AgNPs against clinical oral biofilms associated with dental caries and periodontal disease. The aim of this study was to determine the antimicrobial and substantivity effects of AgNPs in oral biofilms isolated clinically from patients with dental caries and periodontal disease. Sixty-seven young and young-adult subjects with dental caries and periodontal disease were clinically sampled through the collection of subgingival dental plaque. The inhibitory effect of AgNPs was performed with standard microbiological assays by triplicate using two sizes of particle. Polymerase chain reaction (PCR) assay was used to identify the presence of specific bacterial species. All AgNPs showed an inhibitory effect for all oral biofilms for any age and, generally, any gender (p>0.05); however, the effectiveness of the antimicrobial and substantivity effects was related to particle size, time, and gender (p<0.05). The identified microorganisms were S. mutans, S. sobrinus, S. sanguinis, S. gordonii, S. oralis, P. gingivalis, T. forsythia, and P. intermedia. The AgNPs could be considered as a potential antimicrobial agent for the control and prevention of dental caries and periodontal disease.


1973 ◽  
Vol 19 (8) ◽  
pp. 973-981 ◽  
Author(s):  
T. Gadbois ◽  
J. De Repentigny ◽  
L. G. Mathieu

We have studied aspects of interbacterial ecology with nutritionally dependent Staphylococcus aureus strains; they were grown in association with Pseudomonas aeruginosa in systems of mixed cultures and infections in vitro in a semisynthetic medium and in vivo in mouse peritoneal cavity and rabbit skin. In mixed cultures and in P. aeruginosa culture filtrates, thymine and tryptophan deficiencies in staphylococci were partly overcome. This is probably because P. aeruginosa supplied the essential metabolites required to ensure growth; however, other metabolic activities could also be involved. Other experiments showed that the sensitivity of thymineless staphylococci to nucleoside inhibitions was alleviated. In mixed infections with P. aeruginosa, the S. aureus thymineless strain has shown a greater ability to survive in the peritoneal cavity of mice than when injected alone, even when one species was injected after the other with different doses of bacteria. The examination of the liquid from the peritoneal cavity of infected mice by fluorescence microscopy after fluorochroming with acridine orange or auramine O has revealed that Pseudomonas endotoxin seems to damage leucocytes and consequently reduces the phagocytosis of Staphylococcus cells.Necrosis in rabbit skin was mainly due to S. aureus when both species were injected together intradermally; the thymineless strain was less harmful than the parent strain.It seems that survival and even growth of nutritionally dependent strains of a bacterial species can be favored by the metabolic activities of another species in mixed cultures and infections, in this instance S. aureus by P. aeruginosa. This phenomenon among others could be a determinant of bacterial pathogenicity for nutritionally dependent pathogenic bacteria; thus associated organisms could determine the effective pathogenicity of nutritionally dependent bacteria by contributing essential nutrilites at the site where infection is initiated.


Life Sciences ◽  
2003 ◽  
Vol 73 (12) ◽  
pp. 1527-1535 ◽  
Author(s):  
Tesfaye Belay ◽  
Hernan Aviles ◽  
Monique Vance ◽  
Kimberly Fountain ◽  
Gerald Sonnenfeld

2003 ◽  
Vol 47 (10) ◽  
pp. 3349-3351 ◽  
Author(s):  
Giuseppantonio Maisetta ◽  
Giovanna Batoni ◽  
Semih Esin ◽  
Filippo Luperini ◽  
Manuela Pardini ◽  
...  

ABSTRACT The in vitro activities of human β-defensin 3 (hBD-3) alone or combined with lysozyme, metronidazole, amoxicillin, and chlorhexidine were investigated with the oral bacteria Streptococcus mutans, Streptococcus sanguinis, Streptococcus sobrinus, Lactobacillus acidophilus, Actinobacillus actinomycetemcomitans, and Porphyromonas gingivalis. hBD-3 showed bactericidal activity against all of the bacterial species tested. The bactericidal effect was enhanced when the peptide was used in combination with the antimicrobial agents mentioned above.


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