The Journal of investigative dermatology
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J. Invest. Dermatol. · Sep 2014
Decreased susceptibility of Staphylococcus aureus small-colony variants toward human antimicrobial peptides.
Staphylococcus aureus is a frequent resident of human nose and skin in many individuals, but it is also able to cause a variety of serious infections including those of the skin and soft tissue. There is increasing evidence that particularly persistent, relapsing, and difficult-to-treat infections caused by S. aureus are associated with the formation of the small-colony variant (SCV) phenotype. The aim of this study was to investigate the hypothesis that (i) skin-derived antimicrobial peptides (AMPs) exhibit a reduced activity against SCVs and (ii) that switching into the SCV phenotype may endow S. aureus with a decreased susceptibility toward the killing activity of human stratum corneum. ⋯ Similarly, a S. aureus hemB mutant displaying the SCV phenotype was less susceptible to the antimicrobial activity of AMPs than its hemB-complemented mutant. These findings were accompanied by a higher resistance of SCVs to the killing activity of human stratum corneum. Switching into the SCV phenotype may help S. aureus to subvert cutaneous innate defense, thus contributing to the establishment and persistence of infection.
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J. Invest. Dermatol. · May 2014
Patient-specific naturally gene-reverted induced pluripotent stem cells in recessive dystrophic epidermolysis bullosa.
Spontaneous reversion of disease-causing mutations has been observed in some genetic disorders. In our clinical observations of severe generalized recessive dystrophic epidermolysis bullosa (RDEB), a currently incurable blistering genodermatosis caused by loss-of-function mutations in COL7A1 that results in a deficit of type VII collagen (C7), we have observed patches of healthy-appearing skin on some individuals. When biopsied, this skin revealed somatic mosaicism resulting in the self-correction of C7 deficiency. ⋯ Our results give proof-of-principle that an inexhaustible supply of functional patient-specific revertant cells can be obtained--potentially relevant to local wound therapy and systemic hematopoietic cell transplantation. This technology may also avoid some of the major limitations of other cell therapy strategies, e.g., immune rejection and insertional mutagenesis, which are associated with viral- and nonviral-mediated gene therapy. We believe this approach should be the starting point for autologous cellular therapies using 'natural' gene therapy in RDEB and other diseases.
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J. Invest. Dermatol. · Jan 2014
Non-melanoma skin cancer incidence and impact of skin cancer screening on incidence.
Non-melanoma skin cancer (NMSC) is the most common malignancy, whose public health significance is often unrecognized. This analysis has two objectives: first, to provide up-to-date incidence estimates by sex, age group, histological type, and body site; and second, to study the impact of skin cancer screening. The impact of screening on NMSC incidence in Schleswig-Holstein, Germany, is analyzed by comparing four time periods of different screening settings (no screening (1998-2000), pilot project (Skin Cancer Research to Provide Evidence for Effectiveness of Screening in Northern Germany, SCREEN, 2003-2004), after SCREEN (2004-2008), and nation-wide skin cancer screening (2008-2010)) to a reference region (Saarland, Germany). ⋯ All age groups in women were affected by the increase, but increases for men were mostly limited to the older age groups. Incidence in Saarland first increased slowly, but increased steeply with the introduction of the nation-wide skin cancer screening in 2008 (+47% for women and +40% for men, reference 2004-2008). Observed changes are most likely attributed to screening activities.