Effect of JP-8 jet fuel exposure on protein expression in human keratinocyte cells in culture

[Proteomic profiling of HaCaT keratinocytes exposed to skin damaging detergents]

The effects of sodium dodecyl sulfate (25 mg/ml) and Triton X-100 (12.5 mg/ml and 25 mg/ml) on the HaCaT immortalized keratinocytes exposed to these surfactants for 48 h were studied. Using shotgun proteomics, a comparative analysis of the proteomic profiles of control and experimental cells after surfactants exposure was carried out. 260 common proteins were identified in control and experimental cells; 33 proteins were found in cells exposed to all three treatments, but not in control cells. These 33 proteins apparently reflect a nonspecific (universal) response of cells to toxic damage by the surfactants. These proteins are associated with activation of cell proliferation, changes in the functional activity of their ER and mitochondria, increased mRNA stability and activation of protein degradation processes in the cells. The possibility of using these proteins as a nonspecific parameter of cell response to cytotoxic damage is discussed. The mass spectrometry proteomics data ("raw", "mgf" and "xml" files) have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the dataset identifiers PXD007789 and PXD007776.

Toxicoproteomic evaluation of carbon nanomaterials in vitro

Carbon nanotubes (CNTs) have already been successfully implemented in various fields, and they are anticipated to have innovative applications in medical science. However, CNTs have asbestos-like properties, such as their nanoscale size and high aspect ratio (>100). Moreover, CNTs may persist in the body for a long time. These properties are thought to cause malignant mesothelioma and lung cancer. However, based on conventional toxicity assessment systems, the carcinogenicity of asbestos and CNTs is unclear. The reason for late countermeasures against asbestos is that reliable, long-term safety assessments have not yet been developed by toxicologists. Therefore, a new type of long-term safety assessment, different from the existing methods, is needed for carbon nanomaterials. Recently, we applied a proteomic approach to the safety assessment of carbon nanomaterials. In this review, we discuss the basic concept of our approach, the results, the problems, and the possibility of a long-term safety assessment for carbon nanomaterials using the toxicoproteomic approach.

Exposure to naphthalene induces naphthyl-keratin adducts in human epidermis in vitro and in vivo

We observed naphthyl-keratin adducts and dose-related metabolic enzyme induction at the mRNA level in reconstructed human epidermis in vitro after exposure to naphthalene. Immunofluorescence detection of 2-naphthyl-keratin-1 adducts confirmed the metabolism of naphthalene and adduction of keratin. We also observed naphthyl-keratin adducts in dermal tape-strip samples collected from naphthalene-exposed workers at levels ranging from 0.004 to 6.104 pmol adduct microg(-1) keratin. We have demonstrated the ability of the human skin to metabolize naphthalene and to form naphthyl-keratin adducts both in vitro and in vivo. The results indicate the potential use of keratin adducts as biomarkers of dermal exposure.

Expression Profiling of Human Epidermal Keratinocyte Response Following 1-Minute JP-8 Exposure

The cDNA microarray analysis of 9600 expressed sequence tags was performed to examine the gene expression changes in human epidermal keratinocytes after 1-minute JP-8 exposure; 151 genes were identified as JP-8 responsive and classified into 8 clusters by self organization map. Genes involved in basal transcription and translations were up-regulated, whereas genes related to DNA repair, metabolism, and keratin were mostly down-regulated. Genes encoded for growth factors, apoptosis, signal transduction, and adhesion were also altered. These results indicated that human keratinocyte responds to a single dose of JP-8 insult and revealed several cellular processes previously not associated with jet fuel exposure.

Characterization of microfluidic human epidermal keratinocyte culture

Human epidermal keratinocytes (HEK) are skin cells of primary importance in maintaining the body's defensive barrier and are used in vitro to assess the irritation potential and toxicity of chemical compounds. Microfluidic systems hold promise for high throughput irritant and toxicity assays, but HEK growth kinetics have yet to be characterized within microscale culture chambers. This research demonstrates HEK patterning on microscale patches of Type I collagen within microfluidic channels and maintenance of these cells under constant medium perfusion for 72 h. HEK were shown to maintain 93.0%-99.6% viability at 72 h under medium perfusion ranging from 0.025-0.4 mul min(-1). HEK maintained this viability while approximately 100% confluent-a level not possible in 96 well plates. Microscale HEK cultures offer the ability to precisely examine the morphology, behavior and viability of individual cells which may open the door to new discoveries in toxicological screening methods and wound healing techniques.