The living skin equivalent as a model in vitro for ranking the toxic potential of dermal irritants

Swiderek, Mark; Nelson, Douglas L.; Ernesti, A.

doi:10.1016/0887-2333(92)90020-r

Cited by 93 publications

(36 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We propose that highly porous AgMPs can be used as an alternative to AgNPs in skin substitutes or wound dressings for infected wound sites. Future studies should investigate the cytotoxicity of nanofibers containing different concentrations of AgMPs both in vitro using skin equivalents, 34 which have many morphologic and phenotypic properties of human skin, and in vivo and assess the degradation of particles over extended durations.…”

Section: Discussionmentioning

confidence: 99%

Skin Tissue Engineering for the Infected Wound Site: Biodegradable PLA Nanofibers and a Novel Approach for Silver Ion Release Evaluated in a 3D Coculture System of Keratinocytes and Staphylococcus aureus

Mohiti-Asli

Pourdeyhimi

Loboa

2014

Tissue Engineering Part C: Methods

View full text Add to dashboard Cite

Wound infection presents a challenging and growing problem. With the increased prevalence and growth of multidrug-resistant bacteria, there is a mounting need to reduce and eliminate wound infections using methodologies that limit the ability of bacteria to evolve into further drug-resistant strains. A well-known strategy for combating bacterial infection and preventing wound sepsis is through the delivery of silver ions to the wound site. High surface area silver nanoparticles (AgNPs) allowing extensive silver ion release have therefore been explored in different wound dressings and/or skin substitutes. However, it has been recently shown that AgNPs can penetrate into the stratum corneum of skin or diffuse into the cellular plasma membrane, and may interfere with a variety of cellular mechanisms. The goal of this study was to introduce and evaluate a new type of high surface area metallic silver in the form of highly porous silver microparticles (AgMPs). Polylactic acid (PLA) nanofibers were successfully loaded with either highly porous AgMPs or AgNPs and the antimicrobial efficacy and cytotoxicity of the two silver-based wound dressings were assessed and compared. To better mimic the physiological environment in vivo where both human cells and bacteria are present, a novel coculture system combining human epidermal keratinocytes and Staphylococcus aureus bacteria was designed to simultaneously evaluate human skin cell cytotoxicity with antimicrobial efficacy in a three-dimensional environment. We found that highly porous AgMPs could be successfully incorporated in nanofibrous wound dressings, and exhibited comparable antimicrobial efficacy and cytotoxicity to AgNPs. Further, PLA nanofibers containing highly porous AgMPs exhibited steady silver ion release, at a greater rate of release, than nanofibers containing AgNPs. The replacement of AgNPs with the newly introduced AgMPs overcomes concerns regarding the use of nanoparticles and holds great promise as skin substitutes or wound dressings for infected wound sites.

show abstract

Section: Discussionmentioning

confidence: 99%

Skin Tissue Engineering for the Infected Wound Site: Biodegradable PLA Nanofibers and a Novel Approach for Silver Ion Release Evaluated in a 3D Coculture System of Keratinocytes and Staphylococcus aureus

Mohiti-Asli

Pourdeyhimi

Loboa

2014

Tissue Engineering Part C: Methods

View full text Add to dashboard Cite

show abstract

“…Given the development of these tractable models of human skin that display an unquestionable resemblance to skin in vivo, it is not surprising that these models are being productively utilized in pharmacotoxicological studies (Gay et al, 1992) and in skin grafting procedures (Boyce and Warden, 2002). Furthermore, they provide critical guidance for modeling the complexities of other human organ systems, such as the breast, in culture.…”

Section: Modeling Organs In Vitro: Organotypic Co-culturesmentioning

confidence: 99%

Modeling tissue-specific signaling and organ function in three dimensions

Schmeichel

Bissell

2003

Journal of Cell Science

535

418

View full text Add to dashboard Cite

IntroductionQualitative evaluation of the cellular complexity and structural integrity of organ biopsies has been used by pathologists for decades to gain insight into human diseases. The well-accepted correlation between tissue structure and health or disease conveys important lessons for the development of experimental models for the study of normal human biology and associated disease progression. Optimally, model design should recapitulate both the 3D organization and the differentiated function of any given organ but at the same time allow experimental intervention. By doing so, cell-based models facilitate systematic analyses that address, at the molecular level, how normal organ structure and function are maintained or how the balance is lost in cancer.Because of the ethical, technical and financial constraints inherent in research on human cells and tissues, the demand for models that faithfully parallel human form and function considerably outweighs the supply. We and others asserted more than two decades ago that development of physiologically relevant models of both rodent and human origin should recognize that organs and tissues function in a 3D environment (Elsdale and Bard, 1972;Hay and Dodson, 1973;Bissell, 1981;Ingber and Folkman, 1989). Further, that in the final analysis, the organ itself is the unit of function (Bissell and Hall, 1987). We now know that exposure of cells to the spatial constraints imposed by a 3D milieu determines how cells perceive and interpret biochemical cues from the surrounding microenvironment [e.g. the extracellular matrix, growth factors and neighboring cells (for reviews, see Roskelley et al., 1995;Bissell et al., 2002;Cunha et al., 2002;Ingber, 2002;Radisky et al., 2002)]. Furthermore, it is in this biophysical and biochemical context that cells display bona fide tissue and organ specificity.Here, we describe studies of epithelial-cell-based systems that demonstrate the importance of developing and utilizing 3D human organotypic models to understand the molecular and cellular signaling events underlying human organ biology (Fig. 1). In their most simplistic form, these models comprise homogeneous epithelial cell populations that are cultured within 3D basement-membrane-like matrices. These relatively simple 'monotypic' cell models have progressively evolved into 3D co-culture models containing multiple cell types, which approximate organ structure and function in vitro and enable systematic analyses of the molecular contributions of multiple cell types. Finally, we go on to explore how human 3D culture models are being coupled to existing technologies in the mouse to generate models in vivo that could elucidate the fundamental influence of stromal-epithelial interactions in normal organ function as well as those that perturb organ homeostasis and lead to disease. As a result of these advancements, we are equipped with a hierarchy of related models that appreciate the importance of 3D environments but vary with respect to cellular complexity. By using this collectio...

show abstract

“…The cultures exhibit a well-stratified and cornified epidermis, with basal, spinous and granular layers along with a functional stratum corneum, mimicking the architecture of the normal human skin and allowing the direct topical application of finished products. Various test protocols using these models for acute cutaneous toxicity screening have been proposed [10][11][12][13][14][15][16][17], but their acceptance as valid in vitro alternatives to in vivo studies depends on their reproducibility and relevance.…”

Section: Introductionmentioning

confidence: 99%

Reconstructed Skin Kits: Reproducibility of Cutaneous Irritancy Testing

Faller¹,

Bracher²

2002

Skin Pharmacol Physiol

View full text Add to dashboard Cite

The aim of this study was to determine the reproducibility of data obtained from in vitro irritation testing using three industrial reconstructed human epidermis models, EpiDerm^TM, Episkin^TM and SkinEthic^R, and one in-house model developed at Wella/Cosmital. A common protocol was established based on the measurement of cytotoxicity in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and of extracellular release of proinflammatory mediators and cytosolic enzymes after a range of exposure times to sodium lauryl sulfate (SLS). This time course protocol was applied to 6 different batches of each skin model using triplicate tissue cultures per test condition. The parameters analyzed for intra- and inter-batch reproducibility were the cell viability determined as MTT reduction capacity and the ET-50 values in the 6 batches, as well as the release of the cytokine IL-1α and of the cellular enzymes LDH and GOT in 3 batches only. The MTT viability results showed that EpiDerm was the most resistant to the SLS treatment and at the same time the most reproducible model, SkinEthic was the most sensitive to SLS and the least reproducible, and Episkin and the Cosmital model were intermediate. Measurements of IL-1α release showed a relatively high intra- and inter-batch variability in all the skin models. It was not possible to detect the extracellular release of the enzymes LDH and GOT in the Episkin assay medium. With the 3 other models, the release of LDH and GOT varied in about the same range as that of IL-1α. For all the parameters in this study, the inter-batch variability was generally greater than the intra-batch variability. A possible reduction in the number of batches and replicates for future applications in routine irritancy testing is discussed on the basis of the results obtained using 6 batches in triplicate.

show abstract

The living skin equivalent as a model in vitro for ranking the toxic potential of dermal irritants

Cited by 93 publications

References 58 publications

Skin Tissue Engineering for the Infected Wound Site: Biodegradable PLA Nanofibers and a Novel Approach for Silver Ion Release Evaluated in a 3D Coculture System of Keratinocytes and Staphylococcus aureus

Skin Tissue Engineering for the Infected Wound Site: Biodegradable PLA Nanofibers and a Novel Approach for Silver Ion Release Evaluated in a 3D Coculture System of Keratinocytes and Staphylococcus aureus

Modeling tissue-specific signaling and organ function in three dimensions

Reconstructed Skin Kits: Reproducibility of Cutaneous Irritancy Testing

Contact Info

Product

Resources

About