Melanoma-associated adhesion molecule MUC18/MCAM (CD146) and transcriptional regulator Mader in normal human CNS

The proteins MUC18 and Mader have been identified as markers of tumor progression in melanoma cells, MUC18, also known as MCAM (melanoma cell adhesion molecule) and as CD146 (endothelial antigen), is a cell adhesion molecule belonging to the immunoglobulin superfamily, Mader is a transcriptional regulator shown to negatively regulate EGR-1. As it is known that neoplastic cells of neuroectodermal origin frequently express neuron-specific molecules, we studied whether these melanoma-associated antigens are found in normal CNS tissue. We investigated the expression of MUC18/MCAM and Mader in adult human post mortem CNS tissue by immunohistochemistry, immunoblot and two-dimensional gel electrophoresis. Our results show that Mader is preferentially expressed on neurons and glial cells and that the adhesion protein MUC18/MCAM is mainly expressed on vasculature within the CNS. These observations may have important implications for further studies investigating their possible roles in cell adhesion and proliferation control within the CNS

Melanoma-associated adhesion molecule MUC18/MCAM (CD146) and transcriptional regulator Mader in normal human CNS

The proteins MUC18 and Mader have been identified as markers of tumor progression in melanoma cells, MUC18, also known as MCAM (melanoma cell adhesion molecule) and as CD146 (endothelial antigen), is a cell adhesion molecule belonging to the immunoglobulin superfamily, Mader is a transcriptional regulator shown to negatively regulate EGR-1. As it is known that neoplastic cells of neuroectodermal origin frequently express neuron-specific molecules, we studied whether these melanoma-associated antigens are found in normal CNS tissue. We investigated the expression of MUC18/MCAM and Mader in adult human post mortem CNS tissue by immunohistochemistry, immunoblot and two-dimensional gel electrophoresis. Our results show that Mader is preferentially expressed on neurons and glial cells and that the adhesion protein MUC18/MCAM is mainly expressed on vasculature within the CNS. These observations may have important implications for further studies investigating their possible roles in cell adhesion and proliferation control within the CNS

Recovery of phenol (1) and PAH (2–21) from digested human skin using a combination of vortex and ultrasonic extraction in a 2∶1 benzene/acetone solution and keeper without (white) and loaded with (black) Carbon Black particles.

<p>Recovery ranges from 96–99% for both, without and with adding Carbon Black particles whereby the mean RSD (n = 3) did not exceed 3%.</p

Concentration of single PAH in skin and lymph nodes compared to tattoo inks.

<p>*mean PAH values recently detected in commercially available black tattoo ink suspensions <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092787#pone.0092787-Regensburger1" target="_blank">[16]</a>.</p><p>**taken from the fact sheet of the JRC, Polycyclic Aromatic Hydrocarbons.</p><p>***below detection limit.</p><p>The bold PAH have been proven to be genotoxic in vitro and in vivo according to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092787#pone.0092787-Benford1" target="_blank">[3]</a>.</p

HPLC chromatogramis displayed of all 21 PAH (A), which could be detected at the same time.

<p>HPLC chromatogramsare displayed for a skin sample (B), and for a lymph node sample (C).</p

Total Concentration of PAH in skin and lymph node specimens.

<p>*below detection limit.</p

Histology of skin (top) and from the corresponding lymph node (bottom).

<p>The specimens were embedded in paraffin and, after hematoxylin-eosine (H&E) staining, imaged with a Zeiss Axiostar Plus microscope (10 fold optical magnification). The images show black tattoo particles, which are located inside the dermis or lymph node along with various PAH species as detected by extraction and chemical analysis together with adsorbed hazardous PAH.</p

Specimen of black tattooed human skin (top) and one of the corresponding regional lymph node (center), which was cutted into two pieces.

<p>Transmission electron microscopy shows the shape and size of black tattoo particles, which consist of Carbon Black nanoparticles (bottom).</p

Distribution of nickel and chromium containing particles from tattoo needle wear in humans and its possible impact on allergic reactions

International audienceBackground: Allergic reactions to tattoos are amongst the most common side effects occurring with this permanent deposition of pigments into the dermal skin layer. The characterization of such pigments and their distribution has been investigated in recent decades. The health impact of tattoo equipment on the extensive number of people with inked skin has been the focus of neither research nor medical diagnostics. Although tattoo needles contain high amounts of sensitizing elements like nickel (Ni) and chromium (Cr), their influence on metal deposition in skin has never been investigated.Results: Here, we report the deposition of nano- and micrometer sized tattoo needle wear particles in human skin that translocate to lymph nodes. Usually tattoo needles contain nickel (6–8%) and chromium (15–20%) both of which prompt a high rate of sensitization in the general population. As verified in pig skin, wear significantly increased upon tattooing with the suspected abrasive titanium dioxide white when compared to carbon black pigment. Additionally, scanning electron microscopy of the tattoo needle revealed a high wear after tattooing with ink containing titanium dioxide. The investigation of a skin biopsy obtained from a nickel sensitized patient with type IV allergy toward a tattoo showed both wear particles and iron pigments contaminated with nickel.Conclusion: Previously, the virtually inevitable nickel contamination of iron pigments was suspected to be responsible for nickel-driven tattoo allergies. The evidence from our study clearly points to an additional entry of nickel to both skin and lymph nodes originating from tattoo needle wear with an as yet to be assessed impact on tattoo allergy formation and systemic sensitization