The Gastrointestinal Helminth Heligmosomoides bakeri Suppresses Inflammation in a Model of Contact Hypersensitivity.

Helminths regulate host immune responses to ensure their own long-term survival. Numerous studies have demonstrated that these helminth-induced regulatory mechanisms can also limit host inflammatory responses in several disease models. We used the Heligmosomoides bakeri (Hb) infection model (also known as H. polygyrus or H. polygyrus bakeri in the literature) to test whether such immune regulation affects skin inflammatory responses induced by the model contact sensitiser dibutyl phthalate fluorescein isothiocynate (DBP-FITC). Skin lysates from DBP-FITC-sensitized, Hb-infected mice produced less neutrophil specific chemokines and had significantly reduced levels of skin thickening and cellular inflammatory responses in tissue and draining lymph nodes (LNs) compared to uninfected mice. Hb-induced suppression did not appear to be mediated by regulatory T cells, nor was it due to impaired dendritic cell (DC) activity. Mice cleared of infection remained unresponsive to DBP-FITC sensitization indicating that suppression was not via the secretion of Hb-derived short-lived regulatory molecules, although long-term effects on cells cannot be ruled out. Importantly, similar helminth-induced suppression of inflammation was also seen in the draining LN after intradermal injection of the ubiquitous allergen house dust mite (HDM). These findings demonstrate that Hb infection attenuates skin inflammatory responses by suppressing chemokine production and recruitment of innate cells. These findings further contribute to the growing body of evidence that helminth infection can modulate inflammatory and allergic responses via a number of mechanisms with potential to be exploited in therapeutic and preventative strategies in the future.

Attraction factors for Paederus fuscipes ' dispersal, a vector of Paederus dermatitis towards human residential premises.

Paederus fuscipes, a vector of Paederus dermatitis in most tropical and subtropical countries of the world have a high prevalence in human dwellings due to their positively phototaxic behaviour which has caused a tremendous impact on human health. In this paper, P. fuscipes dispersal flights were studied for two seasons of the rice cultivation phases in residential premises built close to rice field areas (≈32-60 m and 164 m) in mainland Penang, Malaysia. We examined the effects of different light illuminance, building floor level and their association with rice stages as a focal cause of P. fuscipes dispersion from the rice fields towards human dwellings. The present study showed a significant interaction between different light illuminances and rice cultivation phases in attracting P. fuscipes to disperse and invade human dwellings. The highest number of P. fuscipes was captured near the bright light. P. fuscipes flights increased in line with each floor level, and the highest captures took place at higher building floor levels (levels 2 and 3) compared to lower building floor levels (ground floor and level 1) of a three storey apartment in both rice seasons. This finding not only conveys a better understanding on P. fuscipes dispersal pattern, but also draws public attention on the occurrence of dermatitis linearis caused by the Paederus beetles.

Attraction factors for Paederus fuscipes ' dispersal, a vector of Paederus dermatitis towards human residential premises

ABSTRACT Paederus fuscipes, a vector of Paederus dermatitis in most tropical and subtropical countries of the world have a high prevalence in human dwellings due to their positively phototaxic behaviour which has caused a tremendous impact on human health. In this paper, P. fuscipes dispersal flights were studied for two seasons of the rice cultivation phases in residential premises built close to rice field areas (≈32-60 m and 164 m) in mainland Penang, Malaysia. We examined the effects of different light illuminance, building floor level and their association with rice stages as a focal cause of P. fuscipes dispersion from the rice fields towards human dwellings. The present study showed a significant interaction between different light illuminances and rice cultivation phases in attracting P. fuscipes to disperse and invade human dwellings. The highest number of P. fuscipes was captured near the bright light. P. fuscipes flights increased in line with each floor level, and the highest captures took place at higher building floor levels (levels 2 and 3) compared to lower building floor levels (ground floor and level 1) of a three storey apartment in both rice seasons. This finding not only conveys a better understanding on P. fuscipes dispersal pattern, but also draws public attention on the occurrence of dermatitis linearis caused by the Paederus beetles.

Apparent contact dermatitis caused by Ancylostoma caninum: a case report.

Ancylostomum caninum larvae cause damage to the host at the point of entry through the skin leaving a wound vulnerable to secondary infections. As the larvae migrate through the skin an inflammatory response, dermatitis, is often stimulated which can be exacerbated in hosts which give hypersensitive responses. We assessed a 44-year-old man with contact dermatitis diagnosed as nickel allergy but caused by Ancylostoma caninum infection.

Chronic Toxoplasmosis Modulates the Induction of Contact Hypersensitivity by TNCB in Mouse Model.

Mouse models of chronic toxoplasmosis and atopic dermatitis (AD) were combined to clarify the effect of opportunistic Toxoplasma gondii infection on the development of AD. AD was induced as a chronic contact hypersensitivity (CHS) with repeated challenge of 2,4,6-trinitro-1-chlorobenzene (TNCB) on the dorsal skin of mice. TNCB induced skin thickness increases in both normal and toxoplasmic mice. The changing patterns were different from the sigmoidal which saturated at 20 days in normal mice to the convex saturated at 12 days in toxoplasmic mice with the crossing at 18 days. Compared to normal mice, toxoplasmic mice presented CHS more severely in earlier times and then moderately in later times. These data suggest that host immune modification by T. gondii infection enhances CHS in early times of atopic stimulation but soothes the reaction of CHS in later times in mouse model.

Accidentes por lepidópteros: Hylesia nigricans (Berg, 1875) o "mariposa negra" / Accidents due to Lepidoptera: Hylesia nigricans (Berg, 1875) or "mariposa negra"

Las características biológicas de los lepidópteros (mariposas, orugas y polillas) posibilitan el contacto de sus distintos estadios evolutivos con el ser humano. La mariposa nocturna Hylesia nigricans es responsable de brotes epidémicos en nuestro país. Se denomina erucismo al contacto con las larvas u orugas y lepidopterismo, si el contacto se produce con las mariposas. Realizamos una actualización de estos lepidópteros de importancia médica

Lepidoptera (butterflies, caterpillars and moths) biologic features make possible the contact between different instars and humans. The moth Hylesia nigricans is responsible for epidemic outbreaks in our country. It is called erucism when the contact is with caterpillars and lepidopterism when the contact is with moths. We perform an update of these important medical lepidopters.

[Accidents due to Lepidoptera: Hylesia nigricans (Berg, 1875) or "mariposa negra"]. / Accidentes por lepidópteros: Hylesia nigricans (Berg, 1875) o "mariposa negra".

Lepidoptera (butterflies, caterpillars and moths) biologic features make possible the contact between different instars and humans. The moth Hylesia nigricans is responsible for epidemic outbreaks in our country. It is called erucism when the contact is with caterpillars and lepidopterism when the contact is with moths. We perform an update of these important medical lepidopters.

Paederus fuscipes dermatitis: a report of nine cases observed in Italy and review of the literature.

Paederus sp. is a beetle belonging to Staphylinidae family and Coleoptera order. Its distribution is worldwide, especially in hot climates. Over 600 species of Paederus are known, approximately 50 are able to cause an irritant contact dermatitis. When the beetle is accidentally crushed on the skin, it releases pederin, a potent toxin with vesicating action. In Europe, only anecdotical cases of Paederus sp. dermatitis have been reported. Since 1993, we have observed approximately 25 patients with suspected Paederus sp. dermatitis. In 9 the clinical diagnosis was confirmed because Paederus fuscipes were found. The case list includes 6 males and 3 females, ages ranging from 6 to 53 years (mean age: 26.3 years). Six patients presented with one lesion and 3 with 2 lesions. Eyelids (3 patients), shoulders (3), neck (2), cheek (1), breast (1), back (1) and calf (1) were involved. All patients showed erythema, 2 oedema, 2 blisters, 1 vesicles, 1 pustules and 1 crusts. In the patient with pustules, bacteriological examinations were negative. A biopsy was carried out in 4 patients. In the early stages, spongiosis with exocytosis of neutrophils was observed. Vesicles with neutrophils and necrosis of the epidermis were typical of the advanced stage. Oedema of the dermis and a mixed infiltrate, with eosinophils, neutrophils and lymphocytes, in the papillary and upper reticular dermis, were also observed. Direct immunofluorescence was negative in all patients. Paederus sp. should also be considered in temperate climates as a possible aetiological agent in cases of acute dermatitis.

Differential requirements for interleukin (IL)-4 and IL-13 in protein contact dermatitis induced by Anisakis.

BACKGROUND: Exposure to antigens of the fish parasite Anisakis is associated with the development of protein contact dermatitis in seafood-processing workers. Understanding the basic mechanisms controlling allergic sensitization through the skin is critical for designing therapies that will prevent the progression of allergic disease. OBJECTIVE: To investigate the roles of interleukin (IL)-4, IL-13 and the IL-4Ralpha in both local skin pathology and systemic sensitization following epicutaneous exposure to Anisakis proteins. METHODS: BALB/c wild-type (WT) mice and mice deficient in IL-4, IL-13 or IL-4 and IL-13, as well as mice with cell-specific impairment of IL-4Ralpha expression, were sensitized to Anisakis antigen by repeated epicutaneous application of Anisakis extract. Following this sensitization, skin pathology was recorded and systemic responses were investigated. Intravenous challenge with Anisakis extract was performed to test for the development of biologically relevant systemic sensitization. RESULTS: In WT mice, epicutaneous sensitization with Anisakis larval antigens induced localized inflammation, epidermal hyperplasia, production of T(H)2 cytokines, antigen-specific IgE and IgG1. Intravenous challenge of sensitized mice resulted in anaphylactic shock. Interestingly, IL-13 deficient mice failed to develop epidermal hyperplasia and inflammation, whilst anaphylaxis was reduced only in strains deficient either in IL-4 only, or deficient in IL-4 and IL-13 concurrently, as well as in mice deficient in IL-4Ralpha or with impaired IL-4Ralpha expression on CD4(+) T cells. CONCLUSIONS: Interleukin-13 plays a central role in protein contact dermatitis associated with repeated epicutaneous exposure to Anisakis extract, whereas IL-4 drives systemic sensitization and resultant anaphylactic shock.

[Survey on natural nidus of Trichobilharzia in Huainan area].

The life cycle of Trichobilharzia sp. can be completed in Radix auricularia and domestic or wild ducks, and people can contract cercarial dermatitis through water contact. Natural nidus of Trichobilharzia exists in Huainan area.

Exposure to the fish parasite Anisakis causes allergic airway hyperreactivity and dermatitis.

BACKGROUND: Several case reports show allergy and anaphylactic reactions to the fish parasite Anisakis in the domestic and occupational setting. Further research is needed on the prevalence and mechanisms of disease. OBJECTIVE: To determine the prevalence of Anisakis sensitization and related symptoms among workers in 2 fish-processing factories, and to use gene-deficient mice to determine the working mechanisms of Anisakis allergy. METHODS: A modified version of the European Community Respiratory Health Survey was used to interview 578 South African fish-processing workers. Sensitization to Anisakis, seafood, and common aeroallergens was determined by skin prick test. Lung function was measured by spirometry and methacholine challenge. Serum eicosapentaenoic acid levels were used as an index of seafood consumption. Sensitized wild-type, IL-4, or IL-4 receptor alpha-deficient mice were challenged orally with Anisakis extract. Allergic reactions, lung pathology, antibodies, cytokines, mast cell proteases, and histamine were evaluated. RESULTS: The prevalence of sensitization to Anisakis was higher than the prevalence of sensitization to fish (8% vs 6%). Anisakis-specific IgE reactivity was associated with bronchial hyperreactivity and dermatitis, and significantly increased with fish consumption. In mice, Anisakis infective larvae (L3) induced a striking T(H)2/type 2 response. Food-allergic-type reactions induced by oral challenge with Anisakis extract were absent in IL-4 receptor alpha knockout mice. CONCLUSION: Anisakis sensitization in fish-processing workers is associated with allergic symptoms and correlates with high levels of fish consumption. Anisakis proteins induce allergic reactions in sensitized mice by IL-4/IL-13-mediated mechanisms. CLINICAL IMPLICATIONS: Anisakis allergy should be considered in fish-processing workers with allergic symptoms.

Sarcoptic mite hypersensitivity and skin lesions in slaughtered pigs.

The association between papular skin lesions in slaughtered pigs and hypersensitivity to Sarcoptes scabiei var suis was examined in experimental and field studies, and by the retrospective analysis of monitoring records obtained at slaughter. A causal role for S scabiei was indicated by the production of lesions in experimentally infested pigs, by increased clinical mange in herds having high lesion scores, and by a reduction in the severity of lesions after the implementation of more intensive mange control measures. The specificity of the lesions as an indicator of sarcoptic mite hypersensitivity was estimated to be 0.92 from experimental data and 0.79 from field data. Generalised lesions were rare in mange free pigs, indicating that such lesions were highly specific (1.0 from experimental data, greater than 0.98 from field data) for mange. The assessment of the severity of the lesions in samples of slaughtered pigs appears to be a useful aid to assessing the severity of sarcoptic mange in pig herds.

Mite dermatitis other than scabies.

Most mites are small, have mouth parts capable of puncturing, feed on tissue fluids, have a high reproductive rate, and are found in all habitats, including human skin. Mites are important causes of cutaneous diseases and are vectors of important infectious diseases. Mite bites should be considered whenever any unexplained cutaneous eruption is presented to the dermatologist. A knowledge of the biology of the mites that can attack humans is important when taking a history and for identifying the etiology. Treatment of the dermatitis is symptomatic, with a cure depending on the identification and eradication of the causative mite.