Transient epidermal barrier deficiency and lowered allergic threshold in filaggrin-hornerin (FlgHrnr-/- ) double-deficient mice.

BACKGROUND: Filaggrin (Flg) and hornerin (Hrnr) share similar structural and functional features. Both proteins have been implicated as essential proteins for skin barrier maintenance. Loss-of-function mutations of these genes constitute a risk factor for atopic dermatitis and eczema-related asthma. Furthermore, both FLG and HRNR protein levels are downregulated in patients with atopic dermatitis. Thus, mice deficient for Flg and Hrnr provide a novel model to study skin barrier impairment and the susceptibility for cutaneous inflammation. METHODS: By using appropriate targeting vectors and breeding strategies, we established a homozygous FlgHrnr double-deficient (FlgHrnr-/- ) mouse model lacking both genes including the intergenomic sequence. RESULTS: Neonates appeared normal, but developed a transient scaly phenotype with overall flaky appearance, but no overt skin phenotype in adulthood, thereby reflecting a subclinical barrier defect seen in humans. Structurally, FlgHrnr-/- mice displayed a markedly reduced granular layer and a condensed cornified layer. Functionally, FlgHrnr-/- mice showed permeability abnormalities and metabolic aberrations regarding the production of natural moisturizing factors (NMFs) in the stratum corneum. Surprisingly, although the immune system revealed no aberrations under steady-state conditions, FlgHrnr-/- mice are predisposed to mount an allergic contact dermatitis, especially at hapten threshold levels eliciting allergic reactions. CONCLUSIONS: Together, our FlgHrnr-/- mouse model nicely reflects the epicutaneous sensitization susceptibilities and inflammatory reactions to environmental insults in humans with impaired skin barrier functions.

Infliximab-Associated Chronic Inflammatory Central Nervous System Disease and Peroneal Nerve Injury in a Psoriatic Patient Refractory to Treatment: Case Report with 10-Year Follow-Up.

The tumor necrosis factor-α (TNF-α) antagonists infliximab, adalimumab, and etanercept have been approved for the treatment of chronic inflammatory diseases such as rheumatoid arthritis, ankylosing spondylitis, psoriasis, and psoriatic arthritis. Manifestations of demyelinating disease have been reported for patients receiving TNF-α antagonists. We describe a rare manifestation of a chronic inflammatory process affecting both the central and peripheral nervous system in a patient who received infliximab for the treatment of psoriasis and psoriatic arthritis. Infliximab therapy was discontinued and symptoms improved under high-dose intravenous glucocorticoid pulse therapy.

Morphologische Kriterien vesikulobullöser Hauterkrankungen in der konfokalen In-vivo-Laserscanmikroskopie.

HINTERGRUND UND ZIELVORGABEN: Konfokale Laserscanmikroskopie (Reflectance confocal microscopy; RCM) kann eine nützliche Methode für die genaue, schnelle und nicht-invasive Diagnose für vesikullobullöse Hauterkrankungen (VSD) am Krankenbett sein. Das primäre Ergebnis dieser Studie war eine deskriptive statistische Analyse von RCM-Merkmalen, die mit einer ausgewählten Gruppe an VSD einhergehen. PATIENTEN UND METHODEN: Monozentrische Beobachtungsstudie an einer Universitätsklinik für Dermatologie. Vierzig Hautläsionen bei 24 Patienten mit bullösem Pemphigoid (BP), Infektion mit Varizella Zoster (VZI) oder allergischer Kontaktdermatitis (ACD) wurden ausgewertet. ERGEBNISSE: Patienten mit BP, VZI und ACD wurden auf die Anwesenheit eines großen Spektrums an RCM-Merkmalen hin untersucht, darunter die histopathologische Korrelation von Spongiose, Vesikel/Hautblasen, epidermaler Nekrose, pleomorphen, ballonierte Keratinozyten und entzündlichen Infiltraten. Die drei Erkrankungen zeigten spezifische Muster für Auftreten dieser RCM-Merkmale. Wir identifizierten mit Hilfe einer multivariaten Regressionsanalyse einen Satz morphologischer Merkmale bei BP (Vesikel/Hautblasen an der dermoepidermalen Junktionszone, entzündliche Infiltrate in Hautblasen und basalen Epidermisschichten, Spongiose in basalen Epidermisschichten), VZI (Akantholyse im Stratum spinosum, epidermale Nekrose, pleomorphe, ballonierte Keratinozyten, multinukleäre Riesenzellen) und ACD (Mikrovesikel, Spongiose und auffällige entzündliche Infiltrate im Stratum granulosum/spinosum). SCHLUSSFOLGERUNGEN: RCM scheint ein nützliches Werkzeug bei der Analyse und der Unterscheidung einer ausgewählten Gruppe von VSDs zu sein und bietet eine gute Korrelation mit histopathologischen Untersuchungsergebnissen.

Morphologic criteria of vesiculobullous skin disorders by in vivo reflectance confocal microscopy.

BACKGROUND AND OBJECTIVES: Reflectance confocal microscopy (RCM) may be a useful method for accurate, rapid, and noninvasive bedside diagnosis of vesiculobullous skin diseases (VSD). The main outcome measure of this study was a descriptive statistical analysis of RCM features associated with selected group of VSD. PATIENTS AND METHODS: Single-center, observational study at a university-based dermatology department. Forty skin lesions in 24 patients with bullous pemphigoid (BP), varicella zoster virus infection (VZI), or allergic contact dermatitis (ACD) were assessed. RESULTS: Patients with BP, VZI, and ACD were assessed for the presence of a large spectrum of RCM features, among others including histopathological correlates for spongiosis, vesicles/blisters, epidermal necrosis, pleomorphic ballooned keratinocytes, and inflammatory infiltrate. The three conditions showed distinct patterns of occurrence with respect to these RCM features. Using a multivariate regression model, we identified sets of morphologic features in BP (vesicles/blisters at the dermoepidermal junction, inflammatory infiltrate within blisters and basal epidermal layers, spongiosis in basal epidermal layers), VZI (acantholysis in the stratum spinosum, epidermal necrosis, pleomorphic ballooned keratinocytes, multinucleated giant cells), and ACD (microvesicles, spongiosis, and prominent inflammatory infiltrate in the stratum granulosum/spinosum). CONCLUSIONS: RCM seems to be a useful tool in the evaluation and differentiation of a selected group of VSD, and offers a good correlation with histopathological findings.

A lurking threat: transfer of peanut allergy through peripheral blood stem cell transplantation.

BACKGROUND: There exist several reports of atopy and allergen-specific IgE-mediated hypersensitivity transferred by bone marrow transplantation, and it has been concluded that the transfer of allergic reactivity results from adoptive transfer of IgE-producing donor-derived B- and/or plasma cells. To the best of our knowledge we report the first case of peanut allergy after PBSCT. CASE PRESENTATION: A 55-year-old anciently non allergic man with secondary acute myeloid leukemia (AML) received an allogeneic peripheral blood stem cell transplantation from a matched unrelated donor following reduced-intensity conditioning. On day 32 after PBSCT, while still on prophylactic systemic immunosuppression, the patient noticed a first episode of angioedema with swelling of the nasal and oral mucosa 30 min after consuming peanut puffs. In a second episode, eight months after PBSCT, he again developed angioedema, generalized pruritus and nausea within minutes after eating biscuits containing hazelnut and peanut. Moreover, after topical application of a peanut oil-containing ointment, the patient experienced facial erythema and angioedema. Nine months after PBSCT an evaluation for peanut allergy revealed a highly increased specific IgE to peanut of 75.9 kU/l. Accordingly, skin prick tests for peanut extract were also positive. In consequence, the patient was counseled to strictly avoid peanut-related products, and provided with an emergency set. No adverse allergic events have occurred since for an observation time of 15 months after PBSCT. The stem cell donor was contacted and confirmed intolerance to peanuts. His specific serum IgE pattern nine month after PBSCT harvest was analysed and showed similar sensitization profiles compared to those of the transplant recipient. CONCLUSIONS: Because of the close temporal association between the onset of allergic symptoms in the PBSC recipient it is reasonable to assume that the acquired peanut allergy had been transferred from the donor to the recipient by the PBSC graft.

No evidence of persisting unrepaired nuclear DNA single strand breaks in distinct types of cells in the brain, kidney, and liver of adult mice after continuous eight-week 50 Hz magnetic field exposure with flux density of 0.1 mT or 1.0 mT.

BACKGROUND: It has been hypothesized in the literature that exposure to extremely low frequency electromagnetic fields (50 or 60 Hz) may lead to human health effects such as childhood leukemia or brain tumors. In a previous study investigating multiple types of cells from brain and kidney of the mouse (Acta Neuropathologica 2004; 107: 257-264), we found increased unrepaired nuclear DNA single strand breaks (nDNA SSB) only in epithelial cells of the choroid plexus in the brain using autoradiographic methods after a continuous eight-week 50 Hz magnetic field (MF) exposure of adult mice with flux density of 1.5 mT. METHODS: In the present study we tested the hypothesis that MF exposure with lower flux densities (0.1 mT, i.e., the actual exposure limit for the population in most European countries, and 1.0 mT) shows similar results to those in the previous study. Experiments and data analysis were carried out in a similar way as in our previous study. RESULTS: Continuous eight-week 50 Hz MF exposure with 0.1 mT or 1.0 mT did not result in increased persisting unrepaired nDNA SSB in distinct types of cells in the brain, kidney, and liver of adult mice. MF exposure with 1.0 mT led to reduced unscheduled DNA synthesis (UDS) in epithelial cells in the choroid plexus of the fourth ventricle in the brain (EC-CP) and epithelial cells of the cortical collecting duct in the kidney, as well as to reduced mtDNA synthesis in neurons of the caudate nucleus in the brain and in EC-CP. CONCLUSION: No evidence was found for increased persisting unrepaired nDNA SSB in distinct types of cells in the brain, kidney, and liver of adult mice after continuous eight-week 50 Hz magnetic field exposure with flux density of 0.1 mT or 1.0 mT.