[Dithiols as chelators. A cause of bullous skin reactions]. / Chelatbildner mit Thiolaktivität. Auslöser bullöser Hautreaktionen.

Chelation therapy with (RS)-2,3-Bis(sulfonyl)propane-1-sulfonic acid (DMPS) after an occupational lead exposure led to the development of a severe bullous drug eruption. Skin tests and histology/immunohistology of the test reactions indicated a T-cell-mediated immune response against DMPS. Metal-binding thiol groups as in DMPS are chemically highly reactive and therefore effectively mediate the development of immunogenic hapten (DMPS)-protein complexes. Therefore, the pharmacological effects and sensitization potential of dithiols are tightly connected. Cross-reactivity of DMPS to other chelators like D-penicillamine is possible; the indications for chelation therapy should be weighed carefully.

Pyoderma gangraenosum as rare complication of incisional hernia repair in a patient with Werlhof's disease.

On the 3rd day following surgery to repair an incisional hernia, a 67-year-old male patient with Werlhof's disease (idiopathic thrombocytopenic purpura) was diagnosed with a histologically confirmed pyoderma gangraenosum (PG), a rare complication of wound healing. Dexamethasone pulse therapy resulted in rapid remission of the skin lesions. Further improvement was slowed when the patient suffered multiple organ failure in the intensive care unit, delaying his transfer to rehabilitation for 8 weeks. Postoperative PG is always a differential diagnostic possibility in patients with sterile, progressive, painful, ulcerative skin lesions at or near the surgical wound. Unlike most wound healing complications, which are treated by debridement or antibiotics, the treatment of choice for PG is high-dose steroid therapy.

Molecular and functional characterization of the four-transmembrane molecule l6 in epidermal keratinocytes.

In normal human epidermal keratinocytes (NHEK) proteolytic detachment from the substrate induces a complex activation cascade including expression of new proteins, morphological alterations, and the onset of migration for epidermal regeneration. By subtractive cloning we have shown that L6, a four-transmembrane protein, is newly expressed after proteolytic keratinocyte detachment. In this study, we have generated a novel anti-L6 antibody (clone HD-pKe#104-1.1) and investigated L6 expression regulation in vitro and in vivo as well as L6 function in keratinocyte migration. Dispase-mediated detachment induced L6 expression in NHEK at the mRNA and protein level. Immunohistology of skin biopsies displayed a strong expression of L6 in follicular epidermis and epidermolytic lesions of autoimmune bullous dermatoses (bullous pemphigoid, pemphigus vulgaris), but not in normal interfollicular epidermis. In contrast to normal keratinocytes, HaCaT cells showed constitutive L6 expression, indicating a constitutively active phenotype. After artificial wounding of confluent HaCaT cultures, anti-L6 antibody strongly impaired cell migration velocity and migratory reepithelization of the defect, indicating L6 involvement in keratinocyte migration. These findings suggest that L6 is an important activation-dependent regulator of keratinocyte function and epidermal tissue regeneration.