Preparation of liposomal vancomycin and intracellular killing of meticillin-resistant Staphylococcus aureus (MRSA)

Pumerantz, Andrew S.; Muppidi, Krishna; Agnihotri, Sunil A.; Guerra, Carlos; Venketaraman, Vishwanath; Wang, Jeffrey; Betageri, Guru V.

doi:10.1016/j.ijantimicag.2010.10.011

Cited by 86 publications

(74 citation statements)

References 26 publications

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“…S. aureus can survive inside neutrophils (50) and alveolar macrophages (13) and persist in phagolysosomes for 3 to 4 days before escaping into the cytoplasm, resulting in host cell lysis and dissemination (24). We recently confirmed earlier observations indicating that, compared to the standard formulation, conventional liposome encapsulation enhances vancomycin intracellular killing of MRSA (33,35). The present report demonstrates that, compared to the standard formulation, liposome encapsulation increases vancomycin distribution into lung, liver, and spleen tissue while decreasing accumulation within kidneys.…”

Section: Discussionsupporting

confidence: 69%

“…Retrospective analysis from two multinational, prospective, randomized, double-blind studies revealed that the clinical cure rate for vancomycin treatment of documented MRSA pneumonia was 36% compared to 59% for linezolid (52). Inherent pharmacokinetic limitations such as slow, time-dependent killing and poor penetration into lung tissue and alveolar macrophages (10,23,26,30,33,35,43,47) have been blamed for high rates of vancomycin failure (28). Nevertheless, vancomycin is the comparator drug for randomized, double-blind, prospective trials evaluating novel agents (e.g., telavancin) for treatment of hospitalacquired pneumonia due to MRSA (38).…”

Section: Discussionmentioning

confidence: 99%

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PEGylated Liposome Encapsulation Increases the Lung Tissue Concentration of Vancomycin

Muppidi

Wang

Betageri

et al. 2011

Antimicrob Agents Chemother

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Section: Discussionsupporting

confidence: 69%

Section: Discussionmentioning

confidence: 99%

PEGylated Liposome Encapsulation Increases the Lung Tissue Concentration of Vancomycin

Muppidi

Wang

Betageri

et al. 2011

Antimicrob Agents Chemother

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“…Pumerantz et al (16) claimed that No produced by alveolar macrophages play a major microbicide role against S. aureus. According to Sasaki et al (22) , the expression of induced nitric oxyde synthase is initiated 3h after S. aureus infection.…”

Section: Discussionmentioning

confidence: 99%

Immunological parameters of macrophages infected by methicillin resistant/sensitive Staphylococcus aureus

Morais¹,

Costa²,

Almeida³

et al. 2013

J. Bras. Patol. Med. Lab.

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Introduction: Could changes in Staphylococcus aureus cellular walls, which are commonly associated with multidrug resistance phenotype, influence their immune evasion mechanisms? Objective: To evaluate the microbicide response and survival of alveolar macrophages after in vitro infection with methicillin-sensitive and methicillin-resistant Staphylococcus aureus. Material and methods: We used 20 adult, male, albino, Wistar rats. The alveolar macrophage samples were obtained after tracheostomy and bronchoalveolar lavage. The alveolar macrophages were cultured in the proportion of 1:1 cells/ml Roswell Park Memorial Institute (RPMI) medium/well and isolated by plate adhesion. For the assessment of immunological parameters, four systems were established: negative control, positive control, methicillin sensitive S. aureus (MSSA) and methicillin resistant S. aureus (MRSA). Results: When comparing MRSA and MSSA systems, there was no significant difference as to adhesion and phagocytosis rates, superoxide anion production and macrophage viability. By analyzing the kinetics of nitric oxide production, after 4 to 10 hours of cellular culture incubation, there was lower average production of this radical in the MRSA system when compared to MSSA. However, after 12 hours, no differences were detected between both systems. Conclusion: It is claimed that methicillin resistance may be a factor that influences the bacteria's ability to escape from macrophage microbicide response. Although the results of some immunological parameters were similar in the surveyed systems, the oscillations occurred during the production of nitric oxide may contribute significantly to the survival of Staphylococcus aureus.

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“…The positively charged liposomal formulation was composed of DDAB, DPPC, and cholesterol in a ratio of 4:2:1; the negatively charged liposomal formulation was composed of DCP, DPPC, and cholesterol in a ratio of 4:2:1; and the uncharged liposomal formulation was composed of DPPC and cholesterol in a ratio of 6:1. The liposomal formulations were prepared by the dehydration-rehydration method (60,61). Briefly, the lipids were dissolved in the chloroform-methanol solution (2:1 [vol/vol]).…”

mentioning

confidence: 99%

Efficacy and Safety of Liposomal Clarithromycin and Its Effect on Pseudomonas aeruginosa Virulence Factors

Alhajlan

Alhariri

Omri

2013

Antimicrob Agents Chemother

115

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We investigated the efficacy and safety of liposomal clarithromycin formulations with different surface charges against clinical isolates of Pseudomonas aeruginosa from the lungs of cystic fibrosis (CF) patients. The liposomal clarithromycin formulations were prepared by the dehydration-rehydration method, and their sizes were measured using the dynamic-light-scattering technique. Encapsulation efficiency was determined by microbiological assay, and the stabilities of the formulations in biological fluid were evaluated for a period of 48 h. The MICs and minimum bactericidal concentrations (MBCs) of free and liposomal formulations were determined with P. aeruginosa strains isolated from CF patients. Liposomal clarithromycin activity against biofilm-forming P. aeruginosa was compared to that of free antibiotic using the Calgary Biofilm Device (CBD). The effects of subinhibitory concentrations of free and liposomal clarithromycin on bacterial virulence factors and motility on agar were investigated on clinical isolates of P. aeruginosa. The cytotoxicities of the liposome preparations and free drug were evaluated on a pulmonary epithelial cell line (A549). The average diameter of the formulations was >222 nm, with encapsulation efficiencies ranging from 5.7% to 30.4%. The liposomes retained more than 70% of their drug content during the 48-h time period. The highly resistant strains of P. aeruginosa became susceptible to liposome-encapsulated clarithromycin (MIC, 256 mg/liter versus 8 mg/liter; P < 0.001). Liposomal clarithromycin reduced the bacterial growth within the biofilm by 3 to 4 log units (P < 0.001), significantly attenuated virulence factor production, and reduced bacterial twitching, swarming, and swimming motilities. The clarithromycin-entrapped liposomes were less cytotoxic than the free drug (P < 0.001). These data indicate that our novel formulations could be a useful strategy to enhance the efficacy of clarithromycin against resistant P. aeruginosa strains that commonly affect individuals with cystic fibrosis.

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Preparation of liposomal vancomycin and intracellular killing of meticillin-resistant Staphylococcus aureus (MRSA)

Cited by 86 publications

References 26 publications

PEGylated Liposome Encapsulation Increases the Lung Tissue Concentration of Vancomycin

PEGylated Liposome Encapsulation Increases the Lung Tissue Concentration of Vancomycin

Immunological parameters of macrophages infected by methicillin resistant/sensitive Staphylococcus aureus

Efficacy and Safety of Liposomal Clarithromycin and Its Effect on Pseudomonas aeruginosa Virulence Factors

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