Effects of Physiological Electric Fields on Migration of Human Dermal Fibroblasts

Abstract

Endogenous electric currents generated instantly at skin wounds direct migration of epithelial cells and are likely to be important in wound healing. Migration of fibroblasts is critical in wound healing. It remains unclear how wound electric fields guide migration of dermal fibroblasts. We report here that mouse skin wounds generated endogenous electric currents for many hours. Human dermal fibroblasts of both primary and cell-line cultures migrated directionally but slowly toward the anode in an electric field of 50–100 mV mm−1. This is different from keratinocytes, which migrate quickly to the cathode. It took more than 1 hour for dermal fibroblasts to manifest detectable directional migration. Larger field strength (400 mV mm−1) was required to induce directional migration within 1 hour after onset of the field. Phosphatidylinositol-3-OH kinase (PI3 kinase) mediates cathode-directed migration of keratinocytes. We tested the role of PI3 kinase in anode-directed migration of fibroblasts. An applied electric field activated PI3 kinase/Akt in dermal fibroblasts. Dermal fibroblasts from p110γ (a PI3 kinase catalytic subunit) null mice showed significantly decreased directional migration. These results suggest that physiological electric fields may regulate motility of dermal fibroblasts and keratinocytes differently, albeit using similar PI3 kinase-dependent mechanisms.

Eotaxins and CCR3 Interaction Regulates the Th2 Environment of Cutaneous T-Cell Lymphoma

Abstract

CC chemokine receptor 3 (CCR3), the sole receptor for eotaxins, is expressed on eosinophils and T helper type 2 (Th2) cells. In Hodgkin’s disease, eotaxin-1 secreted by fibroblasts collects Th2 cells and eosinophils within the tissue. Similarly, many Th2 cells infiltrate the lesional skin of cutaneous T-cell lymphoma (CTCL). In this study, we investigated the role of eotaxins in the development of the Th2 environment of CTCL. We revealed that fibroblasts from lesional skin of CTCL expressed higher amounts of eotaxin-3 messenger RNA (mRNA) compared with those from normal skin. Lesional skin of CTCL at advanced stages contained significantly higher levels of eotaxin-3 and CCR3 mRNA, compared with early stages of CTCL. IL-4 mRNA was expressed in some cases at advanced stages. Immunohistochemistry revealed that keratinocytes, endothelial cells, and dermal fibroblasts in lesional skin of CTCL showed a stronger expression of eotaxin-3 than did normal skin. CCR3+ lymphocytes and IL-4 expression were observed in some cases of advanced CTCL. Furthermore, both serum eotaxin-3 and eotaxin-1 levels of CTCL patients at advanced stages were significantly higher than those of healthy individuals. The concentrations of these chemokines correlated with serum soluble IL-2 receptor levels. These results suggest that interaction of eotaxins and CCR3 regulates the Th2-dominant tumor environment, which is closely related to the development of CTCL.

Activation of TLR2 by a Small Molecule Produced by Staphylococcus epidermidis Increases Antimicrobial Defense against Bacterial Skin Infections

From the Journal of Investigative Dermatology…
Abstract
Production of antimicrobial peptides by epithelia is an essential defense against infectious pathogens. In this study we evaluated whether the commensal microorganism Staphylococcus epidermidis may enhance production of antimicrobial peptides by keratinocytes and thus augment skin defense against infection. Exposure of cultured undifferentiated human keratinocytes to a sterile nontoxic small molecule of [...]

A Randomized Trial and the Treatment of Pemphigus Vulgaris

From the Journal of Investigative Dermatology…
Abstract
Pemphigus vulgaris is a rare, life-threatening autoimmune disease. Mycophenolate mofetil is a potent immunosuppressant medication approved by the Food and Drug Administration to be used after solid organ transplantation and to treat pemphigus vulgaris. Mycophenolate mofetil has not become the “wonder drug” that had been anticipated based on initial clinical reports. Studies [...]

Massive scalp myiasis with bleeding in a patient with multiple malignancies

From the International Wound Journal…

ABSTRACT

Most cases of myiasis in association with cancer are reported in patients with squamous cell carcinoma of the head and neck region. They are not emergencies. We report a case of massive myiasis of the scalp with bleeding in a patient with an ulcerated squamous cell carcinoma of the scalp, haematological [...]

Vitamin E and Allergic Contact Dermatitis

Reports of vitamin E–induced allergic contact dermatitis (ACD) and frequent use of vitamin-E derivatives (tocopherol, tocopheryl linoleate, tocopherol acetate, etc) in skin care products deserves further investigation into tolerability and suitability of vitamin E in skin care preparations. A PubMed search was conducted to review the prevalence of vitamin E–induced ACD. It revealed 931 cases of vitamin E–induced ACD mainly from one large study. There were no reported deaths and only three patients required hospitalization for treatment. It appears that vitamin E–induced ACD is an uncommon phenomenon; incidence is low despite its widespread use in skin care products. Given its antioxidant and photoprotective properties, vitamin E should remain an ingredient in skin care products.