Dermal Inflammatory Cell Infiltration Research Articles

Histological dermal changes caused by preparation and application procedures in percutaneous dose toxicity studies in dogs, rabbits and rats.

We reevaluated histological slides of dorsal skin in control animals from past percutaneous dose toxicity studies using dogs, rabbits and rats to provide background data concerning histological changes related to preparation and application procedures and vehicles or embrocations of every variety. Acanthosis, dermal or perifollicular inflammatory cell infiltration in dogs; hyperkeratosis, acanthosis, dermal inflammatory cell infiltration or hemorrhage in rabbits; and acanthosis, dermal inflammatory cell infiltration, crust or foreign body granuloma in rats were present as procedure-related underlying histological changes in the control animals. Four mechanical acts, (1) rubbing with gauze to remove an administered substance for reapplication, (2) use of a taut bandage to avoid slipping from the application site, (3) peeling a patch off as a preparation procedure for reapplication, and (4) clipping or shaving, were considered to cause injury to the skin. The degree of influence of the various application procedures was found to be as follows: sham, lotion < cream < ointment and tape in dogs; untreated control, sham < lotion < tape and poultice in rabbits; and sham, sodium carboxymethylcellulose < olive oil and lotion < ointment and tape in rats. The degree of ointment influence on rabbits is equivocal.

Platycodon grandiflorum root-derived saponins attenuate atopic dermatitis-like skin lesions via suppression of NF-κB and STAT1 and activation of Nrf2/ARE-mediated heme oxygenase-1

PurposeThe consequences of precipitously rising allergic skin inflammation rates worldwide have accelerated the risk of atopic dermatitis (AD). Natural product-based agents with good efficacy and low risk of side effects offer promising prevention and treatment strategies for inflammation-related diseases. We have already reported that Platycodon grandiflorum root-derived saponins (Changkil saponins, CKS) have many pharmacological effects, including anti-inflammatory and anti-allergic effects, but its influence on AD remains unclear. Therefore, we evaluated the inhibitory effect of CKS, mainly platycodin D, on AD-like skin symptoms in mice and the possible mechanisms in cells. MethodsMice were sensitized and challenged with 2,4-dinitrochlorobenzene (DNCB). Four weeks after challenge, mice were treated with oral administration of CKS for 4 weeks. In addition, cells were used to evaluate the effect of CKS, mainly platycodin D, on the TARC expression regulated mechanism. ResultsCKS attenuated DNCB-induced dermatitis severity, serum levels of IgE and TARC, and mRNA expression of TARC, TNF-α, IFN-γ, IL-4, IL-5, and IL-13 in mice. Histopathological examination showed reduced thickness of the epidermis/dermis and dermal infiltration of inflammatory cells and mast cells in the ears. Moreover, CKS and platycodin D inhibited TNF-α/IFN-γ-induced TARC expression through the suppression of NF-κB and STAT1 and induction of Nrf2/ARE-mediated hemeoxygenase-1 (HO-1) expression in cells. ConclusionWe suggest that CKS and platycodin D inhibited the development of AD-like skin symptoms by regulating cytokine mediators and may be an effective alternative therapy for AD-like skin symptoms.

Cultivated ginseng inhibits 2,4-dinitrochlorobenzene-induced atopic dermatitis-like skin lesions in NC/Nga mice and TNF-α/IFN-γ-induced TARC activation in HaCaT cells

Ginseng contains many bioactive constituents, including various ginsenosides that are believed to have anti-allergic, anti-oxidant, and immunostimulatory activities; however, its effects on atopic dermatitis (AD) remain unclear. In the current study, we hypothesized that cultivated ginseng (CG) would inhibit 2,4-dinitrochlorobenzene (DNCB)-induced AD-like skin lesions in NC/Nga mice by regulating the T helper (Th)1/Th2 balance. Also, CG inhibits TNF-α/IFN-γ-induced thymus- and activation-regulated chemokine (TARC) expression through nuclear factor-kappa B (NF-κB)-dependent signaling in HaCaT cells. CG ameliorated DNCB-induced dermatitis severity, serum levels of IgE and TARC, and mRNA expression of TARC, TNF-α, IFN-γ, IL-4, IL-5, and IL-13 in mice. Histopathological examination showed reduced thickness of the epidermis/dermis and dermal infiltration of inflammatory cells in the ears. Furthermore, CG suppressed the TNF-α/IFN-γ-induced mRNA expression of TARC in HaCaT cells. CG inhibited TNF-α/IFN-γ-induced NF-κB activation. These results suggest that CG inhibited the development of the AD-like skin symptoms by modulating Th1 and Th2 responses in the skin lesions in mice and TARC expression by suppressing TNF-α/IFN-γ-induced NF-κB activation in keratinocytes, and so may be a useful tool in the therapy of AD-like skin symptoms.

Topical application of Pleurotus eryngii extracts inhibits 2,4-dinitrochlorobenzene-induced atopic dermatitis in NC/Nga mice by the regulation of Th1/Th2 balance

Pleurotus eryngii is a nutritional and medicinal food rich in polysaccharides that enhance the host immune system as a response to various diseases. The present study investigated the effects of P. eryngii extracts (PEE) on the progress of atopic dermatitis (AD)-like skin lesions in NC/Nga mice induced by 2,4-dinitrochlorobenzene (DNCB). We evaluated skin dermatitis severity, ear thickness, histopathological examination, and cytokines level in DNCB-applied mice treated with PEE. Continuous treatment of PEE inhibited the development of the AD-like skin lesions. PEE suppressed DNCB-induced dermatitis severity, serum level of IgE and thymus and activation-regulated chemokine (TARC), and mRNA expression of TNF-α, INF-γ, IL-4, IL-5, and IL-13 in mice. In addition, PEE reduced thickness of the dermis and dermal infiltration of inflammatory cells and mast cells in histopathological examination. These results indicate that PEE inhibits allergic contact dermatitis through the modulating of T helper (Th)1 and Th2 responses and diminishing the inflammatory cells and mast cells infiltration in the skin lesions in NC/Nga mice.

An itchy rash in a young Caucasian woman

We report of a 23-year-old woman who presented with a six-month history of a recurring, pruritic rash located on her chest, upper abdomen and most recently on the lower back. Until then the patient had been healthy. She did not take any medications, was not aware of any allergies or a family his-tory of skin diseases.The rash had occurred initially six months ago and was marked by an acute onset and a chronic recurrent course. The patient noted a timely association between the onset of the skin lesions and the start of a vegetarian diet. Further-more physical activity and sweating worsened the symptoms.Clinically the woman presented with erythematous patches and urticarial papules as well as crusted vesicles and pustules with an erythematous base that were located on the chest and the inframammary folds and distributed in a symmetrical fashion (Figure 1A, B). Under the provisional diagnosis of an autoimmune bullous disease, the woman had recently received systemic and topical corticosteroids. Lesions progressed under this therapy. Additionally, new pink, slightly urticarial papules and plaques developed on the back. Intense pruritus was the main complaint of the patient. This symptom did not respond to antihistamine or steroid therapy.Routine laboratory tests including blood count, blood chemistry, and serum protein levels were normal. No ele-vated antinuclear antibody titers were found. Direct and indirect immunofluorescence assays and an ELISA to rule out an autoimmune bullous disease were performed and were negative.A skin biopsy taken from one of the most recent lesions on the back showed a sparse perivascular lymphocytic cell infiltrate with occasional neutrophils and a discrete edema of the papillary dermis (Figure 2). No epidermal changes were present. In contrast to these subtle changes, a skin biopsy taken from a fully developed inframammary lesion displayed dramatic epidermal changes consisting of ballooning of kera -tinocytes, necrosis en masse of keratinocytes with intraepi-dermal vesiculation and exocytosis of neutrophils and eosin -ophils. The epidermal changes were accompanied by a dense superficial interstitial and perivascular dermal inflammatory cell infiltrate consisting of lymphocytes mainly, but also neu -trophils and eosinophils (Figures 3, 4).The clinical and histopathologic findings summoned up to the diagnosis of prurigo pigmentosa. Alternative diagno-

Therapeutic Effects of Combination Using Glucosamine Plus Tacrolimus (FK‐506) on The Development of Atopic Dermatitis‐Like Skin Lesions in NC/Nga Mice

Tacrolimus (FK-506) has been found to exhibit potent inhibitory effects on spontaneously developed dermatitis. We previously showed that glucosamine prevents the development of Atopic dermatitis (AD)-like skin lesions in NC/Nga mice. The aims of our study were to investigate the synergistic therapeutic efficacy of combination of glucosamine plus FK-506 in dermatophagoides farina (Df)-induced AD-like skin lesions in NC/Nga mice and to determine the underlying therapeutic mechanisms. The Df-induced NC/Nga mice with a clinical score of 8 were used for treatment with glucosamine (500 mg/kg) alone, FK-506 (1.0 mg/kg) or in combination. The synergistic effects of combination therapy were evaluated by dermatitis scores, skin histology and immunological parameters such as IgE, Th2-mediated cytokines and chemokines, CD3(+) T cells and CLA(+) T cells. Combined therapy using glucosamine plus FK-506 improved the development of AD-like skin lesions as exemplified by a significant decrease in total skin symptom severity scores. The suppression of dermatitis by combined therapy was accompanied by a decrease in the plasma level of IgE and in the splenic level of IL-5, IL-13, TARC and eotaxin. Histological finding indicated that the dermal infiltration of inflammatory cells including mast cells and eosinophils was greatly reduced. Particularly, immunohistological evaluation reveals a reduction in CD3(+) T cells and CLA(+) cells in the combined therapy. Our findings suggest that combination therapy of glucosamine plus FK-506 was more synergistic efficacy than single-modality treatment with either alone to improve the development of established dermatitis in NC/Nga mice model. This combined immunosuppressive therapy may provide an effective therapeutic strategy for the treatment of AD.

Platycodi Radix suppresses development of atopic dermatitis-like skin lesions

Platycodi Radix has been used to treat chronic diseases, such as bronchitis, asthma, and hyperlipidemia. In this study, we examined the effect of an aqueous extract, Changkil (CK), from the root of Platycodi Radix on 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like skin lesions. Administration of CK onto DNCB-induced AD-like skin lesions in NC/Nga mice ameliorated lesion intensity scores, levels of IgE, thymus and activation-regulated chemokine (TARC), TNF-α, and IL-4 in serum and ears. In contrast, CK increased level of the immunosuppressive cytokine IL-10. Histopathological examination showed reduced thickness of the epidermis/dermis and dermal infiltration of inflammatory cells in the ears. CK also suppressed TNF-α/IFN-γ-induced mRNA expression and production of TARC in HaCaT cells. CK exerts beneficial effects on AD symptoms, suggesting that CK is an effective potential therapeutic agent for AD.

Confocal microscopic features of scarring alopecia: preliminary report

Lichen planopilaris (LPP) and discoid lupus erythematosus (DLE) are the most common causes of lymphocytic primary cicatricial alopecia. The management of scarring alopecia can be difficult. The combination of clinical, dermoscopy and reflectance confocal microscopy (RCM), a noninvasive, high-resolution imaging technique, examinations have already been demonstrated to be useful for choosing the correct biopsy site in patients with inflammatory skin disease and obtaining microscopic diagnostic criteria. We evaluated the usefulness in practice of RCM for the identification of criteria for LPP and DLE involving the scalp and their management during therapeutic follow-up. Seven white patients with a previously established histological diagnosis of DLE (three) and LPP (four), were included in the study. RCM criteria for primary scarring alopecia were selected: epidermal disarray, spongiosis, exocytosis of inflammatory cells in the epidermis, interface dermatitis, peri- and intra-adnexal infiltration of inflammatory cells, dilated vessels in the dermis, dermal infiltration of inflammatory cells and melanophages and dermal sclerosis. All patients were followed up using RCM during the treatment. During follow-up the RCM evolution of the epidermal, junctional and dermal inflammation were evaluated. A series of RCM features of scalp LPP and DLE were identified that show correlation with the histopathological evaluation. During the treatment follow-up of the cases RCM was shown to be sensitive for the identification of therapeutic response. In our preliminary study the effective usefulness of RCM for the diagnosis of scarring alopecia and follow-up seemed to be evident. Moreover, RCM seems to be also promising for differential diagnosis between the different entities.

Inhibitory effects of Cinnamomum cassia extract on atopic dermatitis-like skin lesions induced by mite antigen in NC/Nga mice

Cinnamomum cassia (C. cassia) has been traditionally used to treat allergic disease as well as dyspepsia, gastritis, and blood circulation disturbances. However, the antiallergic properties of C. cassia have not been fully verified using scientific tools. This study investigated the effectiveness of C. cassia extract (CCE) as an antiallergic agent in atopic dermatitis model and underlying mechanism. The effect of CCE on mite antigen-treated NC/Nga mice was evaluated by examining skin symptom severity, levels of serum IgE, tumor necrosis factor-α (TNF-α), and histamine, skin histology, and mRNA expression of cytokines in the skin lesions. Moreover, the effect of CCE on TNF-α-and interferon-γ (IFN-γ)-induced chemokine production in human keratinocytes was investigated using ELISA. CCE treatment of NC/Nga mice reduced the dermatitis score and the levels of serum IgE, histamine, and TNF-α. Histological examination showed inhibition of the thickening of the epidermis/dermis and reduced dermal infiltration of inflammatory cells. In skin lesions, mRNA expression of IL-4, TNF-α, and thymus and activation-regulated chemokine (TARC) was inhibited by CCE treatment. The production of TARC, macrophage-derived chemokine, and RANTES from IFN-γ-and TNF-α-stimulated human keratinocytes was suppressed by CCE treatment in a dose-dependent manner. CCE inhibits the development of atopic dermatitis-like skin lesions in NC/Nga mice by suppressing the T-helper 2 cell response.

Alopecia in Rhesus macaques correlates with immunophenotypic alterations in dermal inflammatory infiltrates consistent with hypersensitivity etiology

Although alopecia is a commonly recognized problem affecting many captive Rhesus macaque colonies, there is no consensus as to the underlying etiology or appropriate course of management. We performed skin biopsies to assess underlying pathology in alopecic Rhesus macaques and performed immunohistochemical and metachromatic staining of these biopsies to assess the cellular infiltrates. Alopecia is associated with superficial dermal perivascular mononuclear cell infiltrates and skin pathology consistent with chronic hypersensitivity dermatitis. The inflammation is primarily composed of CD4+ cells admixed with histiocytes and mast cells. Inflammation is correlated with degree of alopecia. Further analysis in different groups of macaques revealed that animals born outdoors or infected with lung mites had reduced dermal inflammatory cell infiltrates and a lower incidence of alopecia. These findings support a hypothesis that an altered housing status resulting in decreased pathogen burden in Rhesus macaque colonies may contribute to dermal immunophenotypic alterations and subsequent development of dermatitis with resultant alopecia.

Prevention of UV-Induced Skin Damages by 11,14,17-Eicosatrienoic Acid in Hairless Mice In Vivo

Polyunsaturated fatty acids (PUFAs) are known to play important roles in various physiological and pathological processes. Recent studies have shown that some omega-3 (ω-3) PUFAs, such as eicosapentaenoic acid (EPA) and dodecahexaenoic acid (DHA), have protective effects on acute and chronic UV-induced changes. However, the effects of other ω-3 PUFAs including 11,14,17-eicosatrienoic acid (20:3) (ETA) on UV-induced skin damages are poorly understood. In this study, we investigated the cutaneous photoprotective effects of ETA in hairless mice in vivo. Female HR-1 hairless mice were topically treated with vehicle (ethanol:polyethylene glycol=30:70) only, 0.1% ETA, or 1% ETA once a day for 3 successive days after one time UV irradiation (200 mJ/cm2) on dorsal skins. Skin biopsy was carried out on the fourth day (72 hr after UV irradiation). We found that topical treatment with ETA attenuated UV-induced epidermal and dermal thickness and infiltration of inflammatory cells, and impairment of skin barrier function. In addition, ETA suppressed the expression of IL-1β, COX-2, and MMP-13 induced by UV irradiation. Our results show that the topical application of ETA protects against UV-induced skin damage in hairless mice and suggest that ETA can be a potential agent for preventing and/or treating UV-induced inflammation and photoaging.

A Case of Post-zoster Eosinophilic Dermatosis

Post-zoster eosinophilic dermatosis is a rare disease that occurs as an isotopic response in the region of previously healed herpes zoster. We report here on a case of post-zoster eosinophilic dermatosis that occurred 13 years after an episode of herpes zoster. A 48-year-old woman presented with several pruritic, brown papules and plaques in the same dermatome where her previous episode of herpes zoster had healed. Histopathologically, there was a dermal inflammatory cell infiltration composed of abundant eosinophils, lymphocytes and histiocytes. Based on these clinicopathologic findings, the patient was diagnosed with post-zoster eosinophilic dermatosis.

Systemic PPARγ Ligation Inhibits Allergic Immune Response in the Skin

We have shown previously that specific ligands of the peroxisome proliferator-activated receptor-gamma (PPARgamma) inhibit the systemic allergic immune response. The objective of this study was to investigate the impact of PPARgamma-ligand treatment on the local allergic immune response. We established a murine model exhibiting clinical and histological features of AD-like skin lesions with high reproducibility. In this model, the PPARgamma ligand was applied in an either preventive or therapeutic manner via systemic and local routes. The affected skin areas were assessed by standardized skin score, histological analyses, and immunohistochemical examinations. Our data show that systemic application of PPARgamma ligand by a preventive protocol led to significantly reduced onset of eczematous skin lesions. This was confirmed by histology, showing decreased skin thickness accompanied by significantly reduced infiltrations of CD4+ and CD8+ lymphocytes but also mast cells. Additionally, early allergen-specific IgE and IgG1 responses were reduced (day 21/35), whereas IgG2a levels remained unchanged. In conclusion, our results demonstrate that PPARgamma-ligand treatment inhibits not only systemic allergic immune response, but also local allergen-mediated dermatitis. Our findings point to therapeutic strategies, including a PPARgamma-ligand-based treatment.

Simultaneous detection of eight cytokines in human dermal wounds with a multiplex bead-based immunoassay for wound age estimation

We performed quantification of IL 2, IL 4, IL 6, IL 8, IL 10, GM-CSF, IFN gamma, and TNF alpha in human dermal wounds for wound age estimation. The proliferation of dermal cells and infiltration of inflammatory cells were also analyzed. Neutrophils and macrophages were detected from 2 h post-injury, and strong infiltrations were seen at 33-49 h. T and B lymphocytes also infiltrated simultaneously from 71 h. Strong proliferation of fibroblasts were shown from 246 h, and thickening of the epidermis from 71 h. IL 10, GM-CSF, IFNgamma, and TNF alpha increased from the early phase of dermal wound healing, IL 6 exclusively in the middle phase, IL 2, IL 4, and IL 8 from the middle phase to the late phase. Among the cytokines analyzed in the present study, IL 6, IL 8, IFNgamma, and TNF alpha were strongly expressed. Results of the present study suggest that multiplex cytokine analysis at the wound site can be useful for wound age estimation. In addition, multiplex data obtained from the same sample with a single method would demonstrate more accurate interactions of cytokines during dermal wound healing. Although the present study was oriented to practical forensic pathology, the data obtained would be informative for various fields of medicine.

Suppression of Spontaneous Dermatitis in NC/Nga Murine Model by PG102 Isolated from Actinidia arguta

Atopic dermatitis (AD) is a chronic inflammatory skin disease, which requires safe and effective pharmacological therapy. We previously found that two preparations from Actinidia arguta, PG102T, and PG102E, could modulate Th1/Th2 pathways and suppress IgE biosynthesis. This study was performed to assess the therapeutic effects of PG102T and PG102E on the development of dermatitis in NC/Nga mice, characterized by the spontaneous onset of AD along with an elevated level of IgE under conventional conditions. PG102T or PG102E administration significantly reduced dermatitis severity as well as scratching tendency in conventional mice. The suppression of dermatitis by PG102 was accompanied by a decrease in the plasma level of IgE, IgG1, and IL-4 and also by an increase in that of IgG2a and IL-12. The splenic level of IL-4, IL-5, and IL-10 was downregulated, whereas that of IFN-gamma and IL-12 was increased. The number of eosinophils and the expression of eotaxin and thymus and activation-regulated chemokine were decreased by PG102T or PG102E. Histological findings also indicated that the thickening of epidermis/dermis and the dermal infiltration of inflammatory cells including mast cells were greatly inhibited. These data suggest that PG102 may be effective therapeutic agents for the treatment of AD.

Ketoprofen: experimental overview of dermal toxicity

Ketoprofen (KP) is a widely used non-steroidal anti-inflammatory drug (NSAID). However, an increasing number of case reports suggest that in broad use, KP can cause allergic dermatitis. Most of these adverse effects have been attributed to the photoallergic potential of KP and photosensitivity. With the exception of a few reports in experimental animals, there is little evidence that KP actually causes dermal toxicity. In this study, in order to investigate the eventual underlying causes of KP dermal toxicity, we conducted primary irritation, skin cumulative, skin sensitization, phototoxicity and photosensitization tests in rodents and rabbits. Primary irritation and skin cumulative testing using New Zealand white rabbits revealed that application of KP (22, 15 and 10%) did not induce erythema or edema formation. Moreover, in skin sensitization and skin phototoxicity testing, using Hartley albino guinea pigs, there was no evidence of allergic or phototoxic potential. In the photosensitization test, KP induced skin reactions in six of eight guinea pigs with signs of erythema on the application site. Histologically, in photosensitized skin, epidermal hyperplasia, including incremental stratum granulosum, acanthosis, keratinocyte hypertrophy and dermal inflammatory cell infiltration, was observed. In this animal study, no primary irritation, cumulative irritation, skin sensitization or skin phototoxicity was observed with KP treatment. However, we identified photosensitization as the underlying cause of KP dermal toxicity.

Preliminary evaluation of in vivo reflectance confocal microscopy features of discoid lupus erythematosus

Discoid lupus erythematosus (DLE) can simulate other inflammatory diseases both clinically and histologically. In vivo reflectance confocal microscopy (RCM) is a noninvasive, reproducible imaging technique already reported to be useful in the evaluation of several inflammatory skin conditions such as contact dermatitis, psoriasis and Darier disease. The aims of our study were to define RCM features of DLE and to evaluate its feasibility in biopsy site selection. Discoid lesions were selected for RCM evaluation from 10 patients with an established diagnosis of DLE. Subsequently, a 4-mm punch biopsy of the same areas evaluated with RCM was rendered for histopathological examination. A series of RCM features of DLE was identified and shown to correlate well with histopathological evaluation. Interface changes, as well as epidermal, dermal and adnexal inflammatory cell infiltration, were identified with RCM in a high percentage of the lesions. A limitation of RCM examination besides imaging depth was the inability to distinguish lymphocytes from other white blood cells. The utility of RCM as a diagnostic tool for DLE awaits further evaluation, although it appears to be promising for biopsy site selection.

Repeated epicutaneous exposures to ovalbumin progressively induce atopic dermatitis‐like skin lesions in mice

Atopic dermatitis (AD) is a chronic skin disease in which environmental factors play a great role. A widely used murine model for AD has provided a useful tool to study the disease. The purpose of this study is to investigate kinetically the induction of this AD model and the processes involved in the development of AD due to extrinsic allergen exposures. BALB/c mice were epicutaneously exposed to ovalbumin (OVA) for 3 weeks; each week was separated by a 2-week resting period. Mice were killed after each exposure week. Skin biopsies and blood were obtained for histological study, RNA isolation and antibody analysis. There was a progressive and significant thickening of the epidermis and dermis in OVA-exposed mice. Significantly increased dermal cell infiltration of eosinophils, mast cells and total inflammatory cells, including CD3 and CD4 cells, was found after each OVA exposure week. Total IgE, IgG2a and OVA-specific IgE were significantly increased after the second and third exposure week, while OVA-specific IgG2a was significantly induced after the third exposure week. Gradual and/or significant increases in mRNA expression of IL-1beta, TNF-alpha, IL-4, IL-10, IL-13, IFN-gamma and IL-12p35 were found after each exposure week. Chemokines and their receptors involved in both T-helper type 1 (Th1)- and Th2-type cell recruitment (CCL1, CCL8, CCL11, CCL24, CXCL9, CXCL10, CCR1, CCR3, CCR5, CCR8 and CXCR3) were up-regulated significantly at different time-points. This study provides an insight into the dynamic nature and time-dependent transition of skin inflammation and systemic immune responses in a murine AD model induced by repeated epicutaneous exposures to OVA.

Inhibition of chronic skin inflammation by topical anti-inflammatory flavonoid preparation, ato formula®

Flavonoids are known as natural anti-inflammatory agents. In this investigation, an anti-inflammatory potential of new topical preparation (SK Ato Formula) containing flavonoid mixtures from Scutellaria baicalensis Georgi roots and Ginkgo biloba L. leaves with an extract of Gentiana scabra Bunge roots was evaluated in an animal model of chronic skin inflammation. Multiple 12-O-tetradecanoylphorbol-13-acetate treatments for 7 consecutive days on ICR mouse ear provoked a chronic type of skin inflammation: dermal edema, epidermal hyperplasia and infiltration of inflammatory cells. When topically applied in this model, this new formulation (5-20 microL/ear/treatment) reduced these responses. Furthermore, it inhibited prostaglandin E2 generation (17.1-33.3%) and suppressed the expression of proinflammatory genes, cyclooxygenase-2 and interleulin-1beta in the skin lesion. Although the potency of inhibition was lower than that of prednisolone, all these results suggest that Ato Formula may be beneficial for treating chronic skin inflammatory disorders such as atopic dermatitis.

Lichenoid tattoo reaction responding to topical tacrolimus ointment

Conflict of interest: none declared. A 51‐year‐old man had four tattoos applied to his skin between 1996 and 2001. The first, on his right anterior chest wall, was drawn by a different artist from the other three, which were sited on the left anterior chest wall, the proximal right lower leg and the distal right lower leg, in 1997, 2000 and 2001, respectively. The constituent parts of the dyes used were not known. Within weeks of shaving the hair overlying the leg tattoos, the patient developed severe itching, irritation and associated thickening of the red‐coloured areas of the tattoos (Fig. 1a). Similar but intermittent symptoms arose in the left chest tattoo, while that on the right, by the other artist, remained quiescent. Patch tests to the European standard series and mercury were negative but the patient reacted to disperse blue dyes 106 and 124 at 96 h. Baseline biopsy showed hyperkeratosis and a dense dermal inflammatory cell infiltrate comprising mainly lymphocytes in keeping with a lichenoid reaction. Potent topical steroid treatment was of limited and short‐lived benefit. A trial of topical tacrolimus ointment (0.1%) dramatically relieved his intense itching and after daily application for 3 months, there was evidence of flattening of the thickened red‐dye areas (Fig. 1b). Repeat biopsy after this interval showed histological improvement, with a normal epidermis and a moderate dermal inflammatory cell infiltrate, in keeping with an ongoing hypersensitivity reaction to the tattoo pigment.