scholarly journals Comparative Study of Two-Dimensional (2D) vs. Three-Dimensional (3D) Organotypic Kertatinocyte-Fibroblast Skin Models for Staphylococcus aureus (MRSA) Infection

2021 ◽  
Vol 23 (1) ◽  
pp. 299
Author(s):  
Nilakshi Barua ◽  
Lin Huang ◽  
Carmen Li ◽  
Ying Yang ◽  
Mingjing Luo ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Death ◽  
Apoptotic Index ◽  
Tunel Assay ◽  
Hacat Cells ◽  
Skin Model ◽  
Mrsa Infection ◽  
The Difference ◽  
Mrsa Strains ◽  
3D Skin

The invasion of skin tissue by Staphylococcus aureus is mediated by mechanisms that involve sequential breaching of the different stratified layers of the epidermis. Induction of cell death in keratinocytes is a measure of virulence and plays a crucial role in the infection progression. We established a 3D-organotypic keratinocyte-fibroblast co-culture model to evaluate whether a 3D-skin model is more effective in elucidating the differences in the induction of cell death by Methicillin-resistant Staphylococcus aureus (MRSA) than in comparison to 2D-HaCaT monolayers. We investigated the difference in adhesion, internalization, and the apoptotic index in HaCaT monolayers and our 3D-skin model using six strains of MRSA representing different clonal types, namely, ST8, ST30, ST59, ST22, ST45 and ST239. All the six strains exhibited internalization in HaCaT cells. Due to cell detachment, the invasion study was limited up to two and a half hours. TUNEL assay showed no significant difference in the cell death induced by the six MRSA strains in the HaCaT cells. Our 3D-skin model provided a better insight into the interactions between the MRSA strains and the human skin during the infection establishment as we could study the infection of MRSA in our skin model up to 48 h. Immunohistochemical staining together with TUNEL assay in the 3D-skin model showed co-localization of the bacteria with the apoptotic cells demonstrating the induction of apoptosis by the bacteria and revealed the variation in bacterial transmigration among the MRSA strains. The strain representing ST59 showed maximum internalization in HaCaT cells and the maximum cell death as measured by Apoptotic index in the 3D-skin model. Our results show that 3D-skin model might be more likely to imitate the physiological response of skin to MRSA infection than 2D-HaCaT monolayer keratinocyte cultures and will enhance our understanding of the difference in pathogenesis among different MRSA strains.

scholarly journals VraSR Regulatory System Contributes to the Virulence of Community-Associated Methicillin-Resistant Staphylococcus aureus (CA-MRSA) in a 3D-Skin Model and Skin Infection of Humanized Mouse Model

Biomedicines ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 35
Author(s):  
Nilakshi Barua ◽  
Ying Yang ◽  
Lin Huang ◽  
Margaret Ip
Keyword(s):  
Staphylococcus Aureus ◽  
Skin Lesion ◽  
Regulatory System ◽  
Lesion Size ◽  
Skin Model ◽  
Humanized Mouse ◽  
Humanized Mouse Model ◽  
Mrsa Infection ◽  
3D Skin

The vancomycin-resistance associated sensor/regulator, VraSR two-component regulatory-system (VraSR), regulates virulence and the response of Staphylococcus aureus (SA) to environmental stress. To investigate the role of VraSR in SA skin and soft tissue infections (SSTI), we inactivated the VraSR of a clinical CA-MRSA ST30 strain by insertional mutation in vraR gene using the TargeTron-Gene Knockout System. We constructed an organotypic keratinocyte fibroblast co-culture (3D-skin model) and a humanized mouse as SSTI infection models. In the 3D-skin model, inactivation of VraSR in the strains ST30 and USA300 showed 1-log reduction in adhesion and internalization (p < 0.001) compared to the respective wildtype. The mutant strains of ST30 (p < 0.05) and USA300-LAC (p < 0.001) also exhibited reduced apoptosis. The wildtype ST30 infection in the humanized mouse model demonstrated increased skin lesion size and bacterial burden compared to BALB/c mice (p < 0.01). The response of the humanized mouse towards the MRSA infection exhibited human similarity indicating that the humanized mouse SSTI model is more suitable for evaluating the role of virulence determinants. Inactivation of VraSR in ST30 strain resulted in decreased skin lesion size in the humanized mouse SSTI model (p < 0.05) and reduction in apoptotic index (p < 0.01) when compared with the wildtype. Our results reveal that inactivating the VraSR system may be a potent anti-virulence approach to control MRSA infection.

scholarly journals Staphylococcus aureus Induces Hypoxia and Cellular Damage in Porcine Dermal Explants

2015 ◽  
Vol 83 (6) ◽  
pp. 2531-2541 ◽  
Author(s):  
Abdul G. Lone ◽  
Erhan Atci ◽  
Ryan Renslow ◽  
Haluk Beyenal ◽  
Susan Noh ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Cell Death ◽  
Effective Diffusion ◽  
Oxygen Demand ◽  
Shotgun Proteomics ◽  
Cellular Damage ◽  
Label Free ◽  
Content Type ◽  
Dermal Tissue ◽  
The Difference

We developed a porcine dermal explant model to determine the extent to whichStaphylococcus aureusbiofilm communities deplete oxygen, change pH, and produce damage in underlying tissue. Microelectrode measurements demonstrated that dissolved oxygen (DO) in biofilm-free dermal tissue was 4.45 ± 1.17 mg/liter, while DO levels for biofilm-infected tissue declined sharply from the surface, with no measurable oxygen detectable in the underlying dermal tissue. Magnetic resonance imaging demonstrated that biofilm-free dermal tissue had a significantly lower relative effective diffusion coefficient (0.26 ± 0.09 to 0.30 ± 0.12) than biofilm-infected dermal tissue (0.40 ± 0.12 to 0.48 ± 0.12;P< 0.0001). Thus, the difference in DO level was attributable to biofilm-induced oxygen demand rather than changes in oxygen diffusivity. Microelectrode measures showed that pH within biofilm-infected explants was more alkaline than in biofilm-free explants (8.0 ± 0.17 versus 7.5 ± 0.15, respectively;P< 0.002). Cellular and nuclear details were lost in the infected explants, consistent with cell death. Quantitative label-free shotgun proteomics demonstrated that both proapoptotic programmed cell death protein 5 and antiapoptotic macrophage migration inhibitory factor accumulated in the infected-explant spent medium, compared with uninfected-explant spent media (1,351-fold and 58-fold, respectively), consistent with the cooccurrence of apoptosis and necrosis in the explants. Biofilm-origin proteins reflected an extracellular matrix-adapted lifestyle ofS. aureus. S. aureusbiofilms deplete oxygen, increase pH, and induce cell death, all factors that contribute to impede wound healing.

scholarly journals Comparative Genomics of Vancomycin-Resistant Staphylococcus aureus Strains and Their Positions within the Clade Most Commonly Associated with Methicillin-Resistant S. aureus Hospital-Acquired Infection in the United States

mBio ◽  
2012 ◽  
Vol 3 (3) ◽  
Author(s):  
Veronica N. Kos ◽  
Christopher A. Desjardins ◽  
Allison Griggs ◽  
Gustavo Cerqueira ◽  
Andries Van Tonder ◽  
...  
Keyword(s):  
United States ◽  
Staphylococcus Aureus ◽  
The United States ◽  
Methicillin Resistant ◽  
Content Type ◽  
Mrsa Infection ◽  
Vancomycin Resistant ◽  
Foreign Dna ◽  
Mrsa Strains ◽  
Hospital Acquired

ABSTRACTMethicillin-resistantStaphylococcus aureus(MRSA) strains are leading causes of hospital-acquired infections in the United States, and clonal cluster 5 (CC5) is the predominant lineage responsible for these infections. Since 2002, there have been 12 cases of vancomycin-resistantS. aureus(VRSA) infection in the United States—all CC5 strains. To understand this genetic background and what distinguishes it from other lineages, we generated and analyzed high-quality draft genome sequences for all available VRSA strains. Sequence comparisons show unambiguously that each strain independently acquired Tn1546and that all VRSA strains last shared a common ancestor over 50 years ago, well before the occurrence of vancomycin resistance in this species. In contrast to existing hypotheses on what predisposes this lineage to acquire Tn1546, the barrier posed by restriction systems appears to be intact in most VRSA strains. However, VRSA (and other CC5) strains were found to possess a constellation of traits that appears to be optimized for proliferation in precisely the types of polymicrobic infection where transfer could occur. They lack a bacteriocin operon that would be predicted to limit the occurrence of non-CC5 strains in mixed infection and harbor a cluster of unique superantigens and lipoproteins to confound host immunity. A frameshift indprA, which in other microbes influences uptake of foreign DNA, may also make this lineage conducive to foreign DNA acquisition.IMPORTANCEInvasive methicillin-resistantStaphylococcus aureus(MRSA) infection now ranks among the leading causes of death in the United States. Vancomycin is a key last-line bactericidal drug for treating these infections. However, since 2002, vancomycin resistance has entered this species. Of the now 12 cases of vancomycin-resistantS. aureus(VRSA), each was believed to represent a new acquisition of the vancomycin-resistant transposon Tn1546from enterococcal donors. All acquisitions of Tn1546so far have occurred in MRSA strains of the clonal cluster 5 genetic background, the most common hospital lineage causing hospital-acquired MRSA infection. To understand the nature of these strains, we determined and examined the nucleotide sequences of the genomes of all available VRSA. Genome comparison identified candidate features that position strains of this lineage well for acquiring resistance to antibiotics in mixed infection.

scholarly journals Potensi Ekstrak Atuna racemosa sebagai Anti - Methicillin Resistant Staphylococcus aureus (MRSA)

2017 ◽  
Vol 35 (2) ◽  
pp. 260
Author(s):  
Siti Isrina Oktavia Salasia ◽  
Novra Arya Sandi ◽  
Fajar Budi Lestari ◽  
Verda Farida ◽  
Nurbani Aziz
Keyword(s):  
Staphylococcus Aureus ◽  
Meca Gene ◽  
New Drugs ◽  
Diffusion Test ◽  
Methicillin Resistant ◽  
Causative Agents ◽  
Mrsa Infection ◽  
Polymerase Chain ◽  
Mrsa Strains ◽  
Multiple Antibiotics

Staphylococcus aureus is one of the major causative agents of mastitis in animals and a variety of human diseases such as septicemia, endocarditis, arthritis dan osteomyelitis. Infection of Methicillin-resistant S. aureus (MRSA) has been widely reported and these strains are usually resistant to multiple antibiotics. The purpose of this study was to evaluate the potential of Atuna racemosa, as an alternative herbal medicine against MRSA infection. The MRSA strains were isolated from human and confirmed based on their resistant to various antibiotics and analyzing of the mecA gene by polymerase chain reaction (PCR). Atuna racemosa originated from Ambon, Maluku, Indonesia, were extracted using 70% ethanol. The activities of the Atuna racemosa extract against MRSA were performed by diffusion disc agar and dilussion agar tests. The results showed that Atuna racemosa extract has the barrier effect of MRSA growth at a concentration of 5% in the diffusion test and at a concentration of 7% in the dilution test. Atuna racemosa could be used as an alternative new drugs with dose of 0.07 g/ml (7%) against MRSA which is multi-resistant to many antibiotics. 

scholarly journals Staphylococcus aureus in poultry, with special emphasis on methicillin-resistant strain infection: A comprehensive review from one health perspective

2021 ◽  
pp. 257-267
Author(s):  
Wafaa A. Abd El-Ghany
Keyword(s):  
Staphylococcus Aureus ◽  
Prevention And Control ◽  
Close Contact ◽  
Control Strategies ◽  
Infected Individual ◽  
Surface Proteins ◽  
Methicillin Resistant ◽  
Mrsa Infection ◽  
Mrsa Strains ◽  
And Control

Staphylococcus aureus is a Gram-positive coccus normally present on the skin and internal organs of animals, birds, and humans. Under certain conditions, S. aureus could produce septicemia and affection of the skin, joints, and heart, as well as sepsis and death. The pathogenicity of S. aureus is associated with the presence of some virulent surface proteins and the production of some virulent toxins and enzymes. This pathogen is considered one of the most important and worldwide foodborne causes as it is incriminated in most cases of food poisoning. The hazardous use of antibiotics in the veterinary field leads to the development of multidrug-resistant S. aureus strains that can be transmitted to humans. The incidence of methicillin-resistant S. aureus (MRSA) strains has increased globally. These resistant strains have been detected in live animals, poultry, and humans. In addition, retail animal products, especially those of avian origin, are considered the main source of MRSA strains that can be easily transmitted to humans. MRSA infection is regarded as nosocomial or occupational. Humans get infected with MRSA strains through improper handling or preparation of contaminated animals or poultry carcasses or improper cooking with contaminated meat. Live birds also can transmit MRSA to close-contact workers in poultry farms. Transmission of MRSA infection in hospitals is from an infected individual to a healthy one. Prevention and control of MRSA are based on the application of hygienic measures in farms as well as proper processing, handling, and cooking of retail poultry products. The cooperation between veterinary and human practitioners is a must to avoid the possibility of zoonotic transmission. Accordingly, this review focused on the sources and transmission of MRSA infection, virulence and resistance factors, incidence and prevalence in poultry and different products, antibiotic resistance, and prevention and control strategies.

scholarly journals Commercially Distributed Meat as a Potential Vehicle for Community-Acquired Methicillin-Resistant Staphylococcus aureus

2012 ◽  
Vol 78 (8) ◽  
pp. 2797-2802 ◽  
Author(s):  
Kikuyo Ogata ◽  
Hiroshi Narimatsu ◽  
Masahiro Suzuki ◽  
Wataru Higuchi ◽  
Tatsuo Yamamoto ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Drug Susceptibility ◽  
Methicillin Resistant ◽  
Content Type ◽  
Reading Frame ◽  
Type Iv ◽  
Mrsa Infection ◽  
Stool Samples ◽  
Mrsa Strains ◽  
Meat Samples

ABSTRACTThe incidence of community-acquired methicillin-resistantStaphylococcus aureus(CA-MRSA) infection has been increasing; however, the sources of infection remain unclear. Therefore, we investigated the involvement of meat as a possible mediator of CA-MRSA infection. We examined the distribution of MRSA strains in commercially distributed raw meat samples (n= 197) and diarrheal stool samples of outpatients (n= 1,287) that were collected in Oita Prefecture, Japan, between 2003 and 2009 for routine legal inspections. Fourteen MRSA strains were isolated from three meat and 11 stool samples. Among these, seven isolates from three meat and four stool samples exhibited the same epidemiological marker profiles [coagulase type III, staphylococcal enterotoxin C, staphylococcal chromosomal cassettemec(SCCmec) type IV, ST8,spatype 606 (t1767), and toxic shock syndrome toxin-1 (TSST-1) producing type]. Furthermore, of the seven strains, three isolates from two meat samples and one stool sample collected in 2007 exhibited completely identical characteristics with respect to phage open reading frame (ORF) typing, pulsed-field gel electrophoresis, and drug susceptibility profiles. The results suggest that commercially distributed meat could play a role in the prevalence of CA-MRSA in the community.

scholarly journals Multidrug and Mupirocin Resistance in Environmental Methicillin-Resistant Staphylococcus aureus (MRSA) Isolates from Homes of People Diagnosed with Community-Onset MRSA Infection

2017 ◽  
Vol 83 (22) ◽  
Author(s):  
J. H. Shahbazian ◽  
P. D. Hahn ◽  
S. Ludwig ◽  
J. Ferguson ◽  
P. Baron ◽  
...  
Keyword(s):  
Risk Factors ◽  
Staphylococcus Aureus ◽  
Health Risk ◽  
Home Environment ◽  
One Health ◽  
Increased Risk ◽  
Mrsa Infection ◽  
Mupirocin Resistance ◽  
Mrsa Strains ◽  
Community Onset

ABSTRACT Patients with community-onset (CO) methicillin-resistant Staphylococcus aureus (MRSA) infections contribute to MRSA contamination of the home environment and may be reexposed to MRSA strains from this reservoir. This study evaluates One Health risk factors, which focus on the relationship between humans, animals, and the environment, for the increased prevalence of multiple antimicrobial-resistant MRSA isolates in the home environment. During a trial of patients with CO-MRSA infection, MRSA was isolated from the household environment at the baseline and 3 months later, following randomization of patients and household members to mupirocin-based decolonization therapy or an education control group. Up to two environmental MRSA isolates collected at each visit were tested. MRSA isolates were identified in 68% (65/95) of homes at the baseline (n = 104 isolates) and 51% (33/65) of homes 3 months later (n = 56 isolates). The rates of multidrug resistance (MDR) were 61% among isolates collected at the baseline and 55% among isolates collected at the visit 3 months later. At the baseline, 100% (14/14) of MRSA isolates from rural homes were MDR. While antimicrobial use by humans or pets was associated with an increased risk for the isolation of MDR MRSA from the environment, clindamycin use was not associated with an increased risk for the isolation of MDR MRSA. Incident low-level mupirocin-resistant MRSA strains were isolated at 3 months from 2 (5%) of 39 homes that were randomized to mupirocin treatment but none of the control homes. Among patients recently treated for a CO-MRSA infection, MRSA and MDR MRSA were common contaminants in the home environment. This study contributes to evidence that occupant use of antimicrobial drugs, except for clindamycin, is associated with MDR MRSA in the home environmental reservoir. (This study has been registered at ClinicalTrials.gov under registration no. NCT00966446.) IMPORTANCE MRSA is a common bacterial agent implicated in skin and soft tissue infections (SSTIs) in both community and health care settings. Patients with CO-MRSA infections contribute to environmental MRSA contamination in these settings and may be reexposed to MRSA strains from these reservoirs. People interact with natural and built environments; therefore, understanding the relationships between humans and animals as well as the characteristics of environmental reservoirs is important to advance strategies to combat antimicrobial resistance. Household interactions may influence the frequency and duration of exposure, which in turn may impact the duration of MRSA colonization or the probability for recurrent colonization and infection. Therefore, MRSA contamination of the home environment may contribute to human and animal recolonization and decolonization treatment failure. The aim of this study was to evaluate One Health risk factors that may be amenable to intervention and may influence the recovery of MDR and mupirocin resistance in CO-MRSA isolates.

scholarly journals Frequencies and Antimicrobial Susceptibility of Methicillin-Resistant Staphylococcus aureus (MRSA) Isolated from Horses in South Korea

2018 ◽  
Vol 12 (1) ◽  
pp. 148-155
Author(s):  
Seoung-Kyoon Choi ◽  
Ji-Yong Hwang ◽  
Chul-Song Park ◽  
Gil-Jae Cho
Keyword(s):  
Staphylococcus Aureus ◽  
South Korea ◽  
Antimicrobial Susceptibility ◽  
Test Method ◽  
Methicillin Resistant ◽  
Treatment And Prevention ◽  
Horse Riding ◽  
Horse Farms ◽  
Mrsa Infection ◽  
Mrsa Strains

Background:Methicillin-ResistantStaphylococcus Aureus(MRSA) has become one of the most prevalent pathogens in animals and humans giving rise to various diseases. MRSA infection in horses and transmission between horses and humans have dramatically increased recently.Objective:This study investigated the isolation frequency and antimicrobial susceptibility of MRSA isolated from horses in South Korea.Method:Screening of the MRSA isolates was conducted by conventional methods and multiplex Polymerase Chain Reaction (PCR). Minimum Inhibitory Concentration (MIC) of oxacillin was determined by the broth microdilution test method. Overall antibiogram was obtained by disk diffusion susceptibility test. All antimicrobial tests were conducted in accordance with the Clinical and Laboratory Standards Institute (CLSI) guidelines.Results:S. aureuswas isolated from 116 (19.46%) of 596 horses tested. Of the 116S. aureusisolates, 52 (8.72%) strains were identified as MRSA by multiplex PCR. Among the 52 MRSA strains, 24 (46.15%) and 28 (53.85%) were oxacillin-resistant MRSA (OR-MRSA) and oxacillin-susceptible MRSA (OS-MRSA), respectively. OR-MRSA showed the highest susceptibility to florfenicol (100.00%), followed by doxycycline (95.83%), cefepime (91.67%), tetracycline (75.00%), and trimethoprim/sulphamethoxazole (70.83%). OS-MRSA showed the highest susceptibility to florfenicol (100.00%) and trimethoprim/sulphamethoxazole (100.00%), followed by cefoxitin (96.43%), ciprofloxacin (92.86%), enrofloxacin (92.86%), lincomycin + spectinomycin (89.29%), cefuroxime (89.29%), and cefonicid (89.29%).Conclusion:This study may facilitate treatment and prevention of MRSA infections and further benefit not only horses, but also people related with horse farms, horse riding clubs and animal hospitals.

scholarly journals Methicillin-Resistant Staphylococcus aureus spa Type t002 Outbreak in Horses and Staff at a Veterinary Teaching Hospital after Its Presumed Introduction by a Veterinarian

2015 ◽  
Vol 53 (9) ◽  
pp. 2827-2831 ◽  
Author(s):  
Amir Steinman ◽  
Samira Masarwa ◽  
Sharon Tirosh-Levy ◽  
Dan Gleser ◽  
Gal Kelmer ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Teaching Hospital ◽  
Large Animal ◽  
Prevalence Survey ◽  
Methicillin Resistant ◽  
Content Type ◽  
Staff Members ◽  
Cross Transmission ◽  
Mrsa Infection ◽  
Mrsa Strains

Methicillin-resistantStaphylococcus aureus(MRSA) infection and colonization, involving MRSA strains which differ from common human health care-associated clones, have become serious emerging conditions in equine veterinary hospitals. In 2010, MRSAspatype t535 caused an outbreak involving both horses and personnel in a veterinary teaching hospital in Israel. Since then, surveillance continued, and occasional MRSA isolation occurred. Two years later, MRSA of anotherspatype, t002, was isolated from a veterinarian and, 3 weeks later, from a horse. The appearance ofspatype t002, a common clone in human medicine in Israel, among both personnel and horses, prompted a point-prevalence survey of hospital personnel and hospitalized horses. Fifty-nine staff members (n= 16 equine;n= 43, other) and 14 horses were screened. Ten of 59 staff members (16.9%) and 7 of 14 horses (50%) were MRSA carriers. Among the staff, 44% of large animal department (LAD) personnel, compared with only 7% of non-LAD personnel, were carriers. Isolates from all horses and from 9 of 10 personnel were found to be of MRSAspatype t002. This clone was later isolated from an infected postoperative wound in a hospitalized horse. Measures were taken to contain transmission between horses and personnel, as was done in the previous outbreak, resulting in reduction of transmission and, finally, cessation of cross-transmission between horses and personnel.

Changing epidemiology of methicillin-resistantStaphylococcus aureusin Alberta, Canada: population-based surveillance, 2005–2008

2010 ◽  
Vol 139 (7) ◽  
pp. 1009-1018 ◽  
Author(s):  
J. KIM ◽  
C. FERRATO ◽  
G. R. GOLDING ◽  
M. R. MULVEY ◽  
K. A. SIMMONDS ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Antimicrobial Susceptibility ◽  
Population Based ◽  
Age Group ◽  
Prospective Surveillance ◽  
Methicillin Resistant ◽  
Source Of Infection ◽  
Mrsa Infection ◽  
Mrsa Strains ◽  
Predominant Strain

SUMMARYIncreasing prevalence of methicillin-resistantStaphylococcus aureus(MRSA) has been reported in Canada. We report the results of a prospective surveillance of MRSA infections in Alberta over a consecutive 3-year period. A total of 8910 unique clinical MRSA isolates was analysed from July 2005 to June 2008. The incidence of MRSA infection increased over the study period and was highest in males, age group ⩾85 years, and the Calgary Area. CMRSA10 (USA300) and CMRSA2 (USA100/800) were the most common PFGE strain types, representing 53·0% and 27·9% of all isolates, respectively. Significant differences were noted between MRSA strains in the source of infection and antimicrobial susceptibility. The incidence of MRSA infection in Alberta has nearly doubled in the last 3 years; this is attributed to the emergence of CMRSA10 as the predominant strain.

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