Prolonged photosensitivity following contact photoallergy to ketoprofen

We report the third case of prolonged photosensitivity secondary to contact photoallergy to topical ketoprofen, a 2-arylpropionic acid derivative. The patient suffered from persistent photosensitivity for more than 1 year after the withdrawal of ketoprofen with recurrent eruptions on sun-exposed skin areas. This photosensitivity was associated with a persistent decrease in polychromatic and UVA minimal erythemal doses. Photobiological testing revealed cross-reactivity with fenofibrate and benzophenones. Photoallergy to ketoprofen is due to the benzophenone structure or to the very similar thiophene phenylketone of tiaprofenic acid, but not to the arylpropionic function. Thus, fenofibrate, tiaprofenic acid and benzophenones should be avoided by patients with a positive history of photocontact dermatitis to ketoprofen.     

CC chemokine receptor 4 expression on peripheral blood CD4+ T cells reflects disease activity of atopic dermatitis

Recent studies indicate that Th1 and Th2 cells differ in their chemokine receptor expression and their responsiveness to various chemokines. Therefore, selective Th2 cell recruitment in Th2-predominant inflammatory diseases such as atopic dermatitis may be under the influence of some chemokines. It is reported that CC chemokine receptor (CCR) 4 is selectively expressed on Th2 cells whereas CXC chemokine receptor (CXCR) 3 is selectively expressed on Th1 cells. In this study we examined CCR4 and CXCR3 expression on peripheral blood CD4+ and CD8+ T cells obtained from adult atopic dermatitis subjects, and compared the results with those from patients with psoriasis vulgaris and healthy controls. CCR4 was preferentially expressed on CD4+ T cells from atopic dermatitis subjects and CXCR3 was preferentially expressed on CD4+ T cells from psoriasis vulgaris subjects. This CCR4 expression was prominent especially in severe atopic dermatitis subjects. CCR4 expression on CD4+ T cells in severe atopic dermatitis subjects decreased on improvement of disease activity. CD25 was preferentially expressed on CCR4+CD4+ T cells but not on CXCR3+CD4+ T cells in atopic dermatitis subjects. Cutaneous lymphocyte-associated antigen was also preferentially expressed on CCR4+CD4+ T cells but not on CXCR3+CD4+ T cells in atopic dermatitis subjects. CD4+ T cells in atopic dermatitis skin lesions were predominantly CCR4+ cells. Taken together, this study strongly indicates that CCR4+CD4+ T cells reflect disease activity and suggests that CCR4 expression is important for T cell infiltration into atopic dermatitis lesions. Thus, CCR4 may be a possible target for therapy of atopic dermatitis in the future.     

Stimulation of Langerhans cells with ketoprofen plus UVA in murine photocontact dermatitis to ketoprofen

BACKGROUND: Ketoprofen (KP) clinically evokes the allergic type of photocontact dermatitis when applied to the skin and irradiated with ultraviolet A (UVA). We have established a murine model of photocontact dermatitis to KP, which is a T cell-mediated delayed type hypersensitivity. OBJECTIVE: To further explore the mechanism underlying this sensitivity, we investigated whether KP plus UVA activates the antigen-presenting ability of Langerhans cells (LCs). METHODS: We analyzed the expression of surface molecules on LCs in the murine epidermis treated with KP plus UVA by immunohistochemistry and flow cytometry. Changes in the cytokine expression of epidermal cells from KP-phototreated skin were also examined by real-time PCR. RESULTS: LCs became larger after treatment with KP plus UVA. The number of LCs was significantly decreased 2-3 days after KP phototreatment and recovered on day 5. A flow cytometric analysis revealed that KP plus UVA increased the percentage of LCs that highly expressed MHC class II, CD86, CD80, CD54 and CD40, whereas neither KP nor UVA alone enhanced the expression. KP phototreatment augmented the expression of I-A and CD86 on LCs in KP and UVA dose-dependent manners. A real-time PCR analysis of KP-phototreated skin showed that the expression of mRNA for IL-1alpha and GM-CSF was immediately increased after treatment. CONCLUSION: A photosensitizing regimen of KP plus UVA activates LCs at least partly by stimulating keratinocytes to produce cytokines. Two strains of mice (BALB/c and AKR) differ in responsiveness to KP and the difference is not related to the activation of keratinocytes.     

两种变应原致小鼠变应性接触性皮炎的研究

目的 建立两种变应性接触性皮炎(ACD)小鼠模型,并探讨其机制。方法 分别以二硝基氟苯和荧光素-5-异硫氰酸盐作为致敏剂,以腹部致敏、耳部激发的方法建立两种ACD小鼠模型。激发前后测量耳廓厚度,计算耳肿胀度;H-E染色观察耳组织病理改变。用免疫组化法检测局部皮损中及用ELISA法检测淋巴结细胞分泌的Th1型/Th2型细胞因子水平。结果 ①成功建立两种ACD小鼠模型。②两种模型的局部皮损中细胞因子的表达有差异。二硝基氟苯组以白介素2表达为主;异硫氰酸荧光素组以白介素4表达为主。③二硝基氟苯组淋巴结细胞分泌干扰素酌的量是异硫氰酸荧光素组的5倍多;异硫氰酸荧光素组淋巴结细胞分泌白介素4的量是二硝基氟苯组的约2倍。结论 二硝基氟苯诱导以Th1型细胞因子占优势的ACD,异硫氰酸荧光素诱导以Th2型细胞因子占优势的ACD。     

趋化性细胞因子受体CCR4和CXCR3在特应性皮炎患者外周血的表达

目的为研究特应性皮炎患者外周血趋化性细胞因子受体CCR4和CXCR3在特应性皮炎的发病过程中的作用。方法采用三色流式细胞仪测定20例特应性皮炎患者和30例健康对照者外周血趋化性细胞因子受体CCR4和CXCR3的表达水平。结果特应性皮炎患者外周血CCR4+CD4+T细胞的水平明显高于对照组(P<0.01);特应性皮炎患者外周血CCR4/CXCR3比率明显高于对照组P<0.01);特应性皮炎患者外周血CXCR3+CD4+T细胞的水平与对照组差异无统计学意义。结论趋化性细胞因子受体CCR4可能促进了Th2细胞从血液进入特应性皮炎患者炎症皮损。     

Photohapten TCSA painting plus UVA irradiation of murine skin augments the expression of MHC class II molecules and CD86 on Langerhans cells

Hapten painting of skin is known to augment the expression of major histocompatibility complex (MHC) class II, CD54, and CD86 on Langerhans cells. We investigated whether painting with 3,3',4',5-tetrachlorosalicylanilide (TCSA), the representative photohapten, and subsequent irradiation with ultraviolet A (UVA) alter the expression of these surface molecules on epidermal Langerhans cells (LC). BALB/c mice were painted with 5 microl of 0.1% TCSA on the earlobes and irradiated with 16 J/cm2 (at 365 nm) of UVA. Epidermal cells were prepared from these earlobes 24 h later, and the levels of MHC class II, CD54, CD80, and CD86 on these cells were analyzed by flow cytometry. As compared with untreated earlobes, the levels of MHC class II and CD86 on LC were markedly augmented and those of CD54 and CD80 were slightly elevated in earlobes treated with TCSA/UVA. Since neither TCSA painting nor UVA exposure alone enhanced the expression, both treatments were essential for enhancement. A dot plot analysis showed the presence of subpopulations of LC expressing MHC class II and CD86 at high levels. The percentage of these highly expressing LC was increased with increasing concentrations of TCSA and doses of UVA up to 1% and 24 J/cm2, respectively. In addition, keratinocyte expression of CD54 was also augmented by TCSA plus UVA. These results suggest that photohaptens, with following UVA exposure, augment the expression of immunologically functional molecules on LC as do ordinary haptens, leading to effective sensitization and elicitation of contact photoallergy.     

Influence of Th2 cells on hair cycle/growth after repeated cutaneous application of hapten

Exposure to contact allergens in order to produce allergic contact dermatitis (ACD) seems to induce hair cycle/growth, but the mechanism of this remains unclear. In the current study, we investigated this mechanism and found that repeated application of hapten induced production of interleukin (IL)‐4 in lymph‐node immune cells. In addition, hair growth was induced in mice after the adoptive transfer of T‐helper (Th)2 cells that had been purified from mice exposed to repeated cutaneous application of hapten. These findings lead us to speculate that Th2 cells that are repeatedly hapten‐sensitized are recruited to hapten‐challenged skin areas, and thus stimulate the production of IL‐4 in the vicinity of the hair follicles, which influences hair cycle/growth. Our results may provide fundamental insights into the mechanism of contact hypersensitivity‐induced hair cycle/growth.     

Cutaneous hypersensitivities to hapten are controlled by IFN-gamma-upregulated keratinocyte Th1 chemokines and IFN-gamma-downregulated langerhans cell Th2 chemokines

There are immediate, late-phase, and delayed-type reactions to exogenous agents. In IFN-gamma-knockout (IFN-gamma(-/-)) and wild-type B6 mice, we examined the response to picryl chloride (PCl) for assessing delayed-type reactions, and the responses to repeatedly challenged FITC for immediate and late-phase reactions. The delayed-type hypersensitivity was depressed in IFN-gamma(-/-) mice, and the immediate and late-phase reactions were enhanced in IFN-gamma(-/-) mice. As skin-infiltrating lymphocytes were scarce at the PCl-challenged site of IFN-gamma(-/-) mice, we investigated chemokine production by keratinocytes and Langerhans cells (LCs). A real-time PCR analysis demonstrated that Th1 chemokines (CXCL9 and CXCL10) and Th2 chemokines (CCL17 and CCL22) were derived mainly from keratinocytes and LCs, respectively. Challenge with PCl or FITC augmented keratinocyte expression of Th1 chemokines in wild-type but not in IFN-gamma(-/-) mice, and Th2 chemokine production by LCs was induced by repeated FITC in IFN-gamma(-/-) mice. Finally, transfer of carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled draining lymph node cells from hapten-sensitized B6 mice or lymph node cells from sensitized green fluorescent protein (GFP) mice to naive IFN-gamma(-/-) mice revealed less infiltration of CFSE(+) or GFP(+) lymphocytes at the challenged site. Our study suggests that one of the crucial actions of IFN-gamma is upregulation of keratinocyte production of Th1 chemokines and downregulation of LC production of Th2 chemokines.     

Chronic actinic dermatitis. Study of the spectrum of chronic photosensitivity in 12 patients

Twelve patients with photodermatitis for longer than 3 months' duration were identified: 1 patient with chronic photocontact dermatitis, 1 with persistent photosensitivity following exposure to a systemic medication, 6 with persistent light reactivity, and 4 with actinic reticuloid. There were 10 men and 2 women, ranging in age from 27 to 81 years, with a mean age of 62 years. The duration of the eruption ranged from 6 months to 20 years. Persistence of photosensitivity to quinidine, which is analogous to persistent light reactivity, was documented in 1 patient, and evolution from photocontact dermatitis to actinic reticuloid was observed in 2 others. These data, along with those reported in the literature, indicate that chronic photocontact dermatitis, persistent photosensitivity to systemic agents, persistent light reactivity, photosensitive eczema, and actinic reticuloid should be considered as entities occurring along a continuum, and the term "chronic actinic dermatitis" is suggested to refer to these entities. Eight (67%) of the 12 patients had skin type VI and 2 others (17%) had skin type V, percentages markedly higher than those of the general patient population, demonstrating that chronic actinic dermatitis is not uncommon among individuals with dark skin.     

Immediate and delayed photocontact dermatitis from isopropyl dibenzoylmethane

Immediate and delayed photocontact dermatitis from the UVA absorber isopropyl dibenzoylmethane is described in 1 patient. In a dose response study in a 2nd patient with delayed photocontact dermatitis, the minimal dose of UVA needed to elicit a positive photopatch to isopropyl dibenzoylmethane 2% was determined to be 2 J/cm2.     

Induction of regulatory T cells by leflunomide in a murine model of contact allergen sensitivity

Allergic contact dermatitis and contact hypersensitivity (CHS) are characterized by allergen-specific activation of CD8+ and CD4+ T cells and the production of cytokines resulting in an inflammatory response and tissue damage. We show here that the immunosuppressive compound leflunomide (N-[4-trifluoro-methylphenyl]-5-methylisoxazol-4 carboxamide, HWA 486) (LF) inhibited the contact allergic response induced in mice by epicutaneous application of the haptens dinitrofluorobenzene (DNFB) and oxazolone. The extent of ear swelling remained significantly reduced following repeated challenge with DNFB for up to 18 weeks. LF and DNFB had to be applied simultaneously for inhibition to occur. The loss of CHS responses was shown to be antigen-specific. Adoptive transfer of leukocytes from LF-treated mice into na?ve mice resulted in a loss of CHS responsiveness. Transfer of both CD4+ and CD8+ cells was required for maximal loss of CHS responses, with CD8+ cells playing a major role. Significantly enhanced levels of IL-10 mRNA were detected in CD8+ T cells, but not in CD4+ T cells, following LF treatment of mice. LF also suppressed CHS responses in mice previously sensitized and challenged with hapten, when administered together with the hapten. Our data suggest that LF induces a long-lived tolerance in mice by inducing CD8+ and CD4+ regulatory T cells.     

Allergic photocontact dermatitis due to suprofen

We report 5 cases of photocontact dermatitis due to suprofen, a nonsteroidal anti-inflammatory drug introduced to the Japanese market in 1989, and available as a 1% ointment. The patients developed pruritic eczematous lesions after applying the ointment for from 2 weeks to 3 months. All 5 patients reacted positively to photopatch testing with ultraviolet A (UVA) and suprofen down to 0.1-0.01% pet., and 3 patients showed positive reactions with ultraviolet B (UVB) and suprofen down to 1.0-0.1%. Moreover, all patients showed a cross-reaction with tiaprofenic acid, which has a very similar chemical structure to suprofen. However, there was no cross-reaction between suprofen and ketoprofen. Prescribers should be aware of the existence of photocontact sensitivity due to these drugs.     

Photocontact dermatitis and chloracne: two major occupational and environmental skin diseases induced by different actions of halogenated chemicals

Among occupational and environmental disorders, contact or photocontact dermatitis and an acneiform eruption are two major skin disorders. Photocontact dermatitis was historically caused by various halogenated salicylanilides, while the acne is induced by halogenated aromatic hydrocarbons and thus called chloracne. Therefore, it should be noted that halogenated chemical compounds are important causative agents in the occupational and environmental medicine. In photocontact dermatitis, photoconjugation of epidermal cells with a photohaptenic halogenated chemical is the initial step. Langerhans cells serve as antigen-presenting cells and T cells sensitized by photoantigen-bearing Langerhans cells induce this photosensitivity. On the other hand, in chloracne, halogeneted hydrocarbons render keratinocytes of the outer root sheath and sebaceous duct hyperplastic. The dilated infundibulum of most hair follicles is then filled with comedone that consist of many accumulated layers of keratinized cells and sebum. Therefore, halogenated chemicals exhibit different actions, i.e. the induction of an immunologic consequence and the modulation of keratinocyte biology. These two conditions also provide good experimental models for investigating dermatology.     

Cannabinoid 1 receptors in keratinocytes attenuate fluorescein isothiocyanate‐induced mouse atopic‐like dermatitis

Atopic dermatitis is a chronic inflammatory disease characterized by an impaired epidermal barrier function combined with a chronic Th2‐type inflammatory response and an intense pruritus. Here, we used an experimental mouse model for Th2‐type contact hypersensitivity (CHS) to fluorescein isothiocyanate (FITC) to investigate the potential role of cannabinoid 1 receptors (CB1) in the pathophysiology of mouse atopic‐like dermatitis. Mice lacking CB1 receptors globally (Cnr1^?/?) or specifically in keratinocytes (KC‐Cnr1^?/?) as well as wild‐type (WT) control mice were sensitized and challenged with FITC. We examined ear swelling responses, transepidermal water loss, Th2‐type skin inflammatory responses and serum IgE levels. Both Cnr1^?/? and KC‐Cnr1^?/? showed enhanced CHS responses to FITC and a delayed epidermal barrier repair when compared with WT mice. mRNA levels for IL‐4, thymic stromal lymphopoietin (TSLP) and CCL8, as well as eosinophil activity, were significantly increased in inflamed ear tissue of FITC‐challenged Cnr1^?/? and KC‐Cnr1^?/? mice. Importantly, CB1 receptor‐deficient keratinocytes secreted increased levels of TSLP, a proinflammatory mediator that drives Th2‐type skin inflammation in atopic dermatitis, under basal and Th2‐type inflammatory conditions. Taken together, our results demonstrate that CB1 receptors in keratinocytes help to maintain epidermal barrier homoeostasis and attenuate Th2‐type allergic inflammatory responses. Based on our work, we propose that enhanced epidermal allergen penetrance cooperates with increased production of TSLP and CCL8 by epidermal keratinocytes for the induction of type 2 CD4+ T helper cells. Our results place keratinocytes at the cross‐roads of outside‐in and inside‐out pathophysiologic mechanisms of atopic dermatitis.     

A Th2 chemokine, TARC, produced by keratinocytes may recruit CLA+CCR4+ lymphocytes into lesional atopic dermatitis skin

Atopic dermatitis is an inflammatory skin disease in which the inflammation is characterized by the influx of lymphocytes into the dermis. It is generally believed that atopic dermatitis is a Th2-type disease, i.e., the T lymphocytes produce interleukin-4, interleukin-5, interleukin-10, and interleukin-13, although it has become evident in recent years that the cytokine profile in the skin changes during the course of the disease towards a Th1-Th2 mixed cytokine profile (interferon-gamma, tumor necrosis factor alpha, and interleukin-2). The lymphocytes that home into the skin express cutaneous lymphocyte-associated antigen, and it has recently been shown that most of the lymphocytes in this population express the chemokine receptor CCR4. CCR4 is the receptor for the CC chemokine TARC (thymus and activation regulated chemokine), and this chemokine is expressed predominantly by keratinocytes in the basal layer of the epidermis of lesional atopic dermatitis skin in mice. In humans, however, it was shown to be expressed in the endothelial cells of the dermis. We have examined the peripheral blood mononuclear cells of atopic dermatitis patients for the expression of cutaneous lymphocyte-associated antigen and CCR4 and compared them with peripheral blood mononuclear cells from normal controls. We found that the proportion of CLA+CCR4+ lymphocytes is upregulated in atopic dermatitis patients. In addition we have examined skin biopsies of lesional and non-lesional skin from atopic dermatitis patients and found that the keratinocytes, but not the endothelial cells, produce TARC in the lesional but not in the nonlesional skin. To gain insight in the stimulatory mechanisms for TARC production in keratinocytes, as previously observed in mice, we cultured HaCaT cells and found that interferon-gamma and tumor necrosis factor alpha work synergistically to induce TARC production. These observations suggest that the induction of TARC production in keratinocytes plays an important role in the late phase skin invasion by CCR4+CLA+ Th2-type lymphocytes in atopic dermatitis.     

Lymphocyte stimulation test with drug-photomodified cells in patients with quinolone photosensitivity.

Quinolone antibacterial agents, known to elicit photosensitive dermatitis as an adverse effect, have both phototoxicity and photoallergenicity. The latter potency is mainly derived from their photohaptenic moiety; quinolones covalently bind to protein and cells upon exposure to ultraviolet A (UVA) light. Our previous study has shown the in vivo and in vitro antigenicity of quinolone-photomodified cells in mice. Here, we examined the presence of sensitized lymphocytes that react with quinolone-photomodified autologous cells in patients with photosensitivity to quinolones. A flow cytometric analysis using a monoclonal antibody specific to quinolone photoadducts demonstrated that peripheral blood mononuclear cells (PBMC) were successfully photomodified with quinolones upon exposure to UVA. PBMC from quinolone-photosensitive patients were cocultured with autologous PBMC photomodified with the causative drug. Modest but significant proliferative responses of responder lymphocytes were found in patients photosensitive to lomefloxacin, fleroxacin, and enoxacin, indicating photoallergic mechanism in these patients. On the other hand, sparfloxacin-photosensitive patients exhibited negative lymphocyte stimulation test, suggesting that its photosensitivity is mainly phototoxic. When UVA-preirradiated quinolones were used as stimulators, only fleroxacin exceptionally stimulated patients' PBMC, indicating its prohaptenic as well as photohaptenic properties. These findings suggest the presence of circulating sensitized T cells in patients with photosensitivity to certain quinolones.     

Contact and photocontact allergy to oxybenzone.

The purpose of this study was to determine the frequency of contact allergy and photocontact allergy to sunscreens. A consecutive series of 54 patients with suspected clinical photosensitivity were assessed. All had the same standardized photobiological investigation from January 1989 to December 1990, including patch tests and photopatch tests with 6 sunscreen agents. Oxybenzone was found to cause 4 cases of allergic contact dermatitis (with photoaggravation in 2), and 3 cases of photocontact dermatitis (13% of patients). This is probably due to the wide distribution of oxybenzone in sunscreens and other cosmetics, 2 patients with polymorphic light eruption and persistent light reactivity, respectively, were regular sunscreen users. Photobiological investigation is necessary to ensure accurate diagnosis, since sunscreen contact or photocontact allergy may simulate other photosensitivity eruptions.     

Photosensitivity reaction to dibucaine. Case report and experimental induction.

In a 13-year-old girl, photoallergic dermatitis was caused by dibucaine hydrochloride, which was used as a local anesthetic in the treatment of her dental caries. The action spectrum for the photosensitivity reaction was in the long-wave ultraviolet (UVA) range. Spectrophotometrically, dibucaine absorbed UVA up to 380 nm, and in the vitro irradiated chemical showed an altered absorption spectrum. The agent is fluorescent under UVA light. The allergic photocontact sensitization could be experimentally induced in guinea pigs. The chemical properties and high sensitization rate of experimental induction suggested that dibucaine may be a potent photosensitizing chemical. Dibucaine should be included in routine photopatch test materials.     

Thymus- and activation-regulated chemokine (TARC/CCL17) induces a Th2-dominated inflammatory reaction on intradermal injection in mice

TARC/CCL17 (thymus- and activation-regulated chemokine) is a CC chemokine, which binds to the CC chemokine receptor-4 (CCR4) known to be distinctively expressed on Th2 lymphocytes. In atopic dermatitis (AD), the skin is invaded by Th2 lymphocytes in the acute phase. TARC/CCL17 is produced by the keratinocytes in AD lesions, and CCR4 is overexpressed on CLA+ (cutaneous lymphocyte-associated antigen) lymphocytes in the skin and blood. We, therefore, hypothesized that TARC/CCL17 is pivotal in mediating a Th2-dominated inflammation in the skin. To examine this, we injected BALB/c mice with murine TARC/CCL17 in concentrations ranging from 0.1 microg/ml to 10 microg/ml and examined the skin after 48 h. This revealed that TARC/CCL17 induces lymphocytic infiltration of the skin by CD4+ lymphocytes in a dose-dependent manner with a maximum response at 1 microg/ml. Additionally, TARC/CCL17 induced interleukin-4 mRNA but not interferon-gamma mRNA expression in the skin, suggesting that the lymphocytes invading the skin are Th2 cells. Additionally, TARC/CCL17 induced its own production in the keratinocytes along with cutaneous T-cell-attracting chemokine (CTACK/CCL27) mRNA. We, therefore, conclude that TARC/CCL17 induces a Th2-dominated inflammatory reaction when injected into the skin.