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Notes: Summary Soluble substances of psoriatic scales (Psoexts) were analysed immunologically to detect immune complex (IC) related to the immune reactions in psoriatic lesions and compared with extracts of scales from a patient with erythroderma due to pityriasis rubra pilaris (PRP-exts) as control. Immunoelectrophoretically IgG, IgA and C3 were detected in Pso-exts, but in PRP-exts only IgG was seen as immunological reactive substances. When analysed by Sephadex G-200 column chromatography, IgG and IgA eluates were found in Pso-exts with a molecular weight of more than 200,000 daltons. By Raji cell assay, the IgG and IgA eluates were shown to have IC characteristics and they were the IC composed of IgG-IgA, which was also confirmed using anti-IgG affinity chromatography. The IC seemed to be binding the epidermal proteins as antigen. Thesefindings suggest that deposits of immunoglobulins and complement in the stratum corneum of psoriatic lesions are not just secondary to the underlying inflammation in the dermis but that the IC detected is related to the immune reactions in psoriatic lesions.

Notes: It is well known that two different photobiologic processes mainly take place when the human skin is exposed to ultraviolet (UV) light. The long waves of UVA and visible light (320–400 nm) irradiation causes skin tanning by melanocytic activation and the short waves of UVB (280–320 nm) can elicit variety of biologic action in cutaneous keratinocytes, melanocytes and other skin component cells. The sensitivity to the UV lights is generally depending on the three kinds of the skin type classified by the proposal of Pathak et al. [1]. The skin sensitivity of Japanese population, however, seems to be different from that of Caucasian's population because of the differences in genetic background and skin color, as indicated by Satoh and Kawada [2]. They tried to classify into three groups as J-I (always burn and rarely tan), J-II (moderately burn and moderately tan) and J-III (never burn and always tan) by the skin types to UV lights for the sun-tanning and sun-burning. Comparing these two criteria, a general concern indicates that J-I–III may correspond to the skin type II–IV of the Fitzpatrick's classification, respectively. Based on the Japanese skin types, the incidence of skin cancers and precancerous lesions related to the long-term exposure of sun-light was epidemiologically estimated by Araki et al. [3]. According to their results for several years (1992–1998), the overall number of skin cancers and precancerous states in Japanese was demonstrated to be small in comparison with the incidence of Caucasian's population, even though the people sets in areas of higher ambient solar radiation. However, working outdoors having J-I and/or a history of severe sunburn during childhood were found to be important risk factors, particularly among people of over 60 years of age. Regarding skin cancers and sun-exposed areas, we compared between 20 patients with skin cancers (males 13 and females seven) (average 65 years old) (〈link href="#t1-14"〉Table I) and 24 controls (males 10 and females 14), who were selected as similar ages to the patients at random, in their skin types and life environments by a questionnaire system. The skin types of the patients were J-I (15%), J-II (40%), and J-III (35%) and those of controls were J-I (4.2%), J-II (62.5%), and J-III (4.2%), respectively. The patient group tended not to protect from sun exposure and most of them were farmers. UV exposure is known to induce modulation of the skin immune system which Langerhans cells decrease in number in the epidermis, and on the other hand it is supposed that interleukin IL-10 producing macrophages (CD11b+) expand in the dermis. Not only IL-10, but also tumor necrosis factor (TNF)-α from macrophages and mast cells in the dermis seem to increase and suppress Th1 immune responses of the epidermis and Th2 immune responses might be induced by UV irradiation [4]. Recently, it has been reported, however, that in patients with polymorphous light eruption (PLE), the expression of TNF-α, IL-4, and IL-10 is reduced by UVB irradiation and that PLE appearance is related to UVB-induced immunosuppression [5].〈tabular xml:id="t1-14"〉I〈title type="main"〉 Twenty patients with skin cancers (average ages: 65 years old) (Department of Dermatology, Fukushima Medical University Hospital, 2001–2002) 〈table frame="topbot"〉〈tgroup cols="2" align="left"〉〈colspec colnum="1" colname="col1"/〉〈colspec colnum="2" colname="col2"/〉〈thead valign="bottom"〉〈row rowsep="1"〉Skin cancersNumber of patients〈tbody valign="top"〉Malignant melanoma8Squamous carcinoma4Bowen's disease4Basal cell carcinomas3Eccrine porocarcinoma1Location of skin cancersSun-exposed areas9Non-exposed areas11Then, we attempted to study UVB effects on atopic disease and chronic inflamed skin diseases in the therapeutic advantage, although it is harmful for the patients to be cutaneous carcinogenesis. The epidermal keratinocytes are capable of producing CC chemokines in the local Th2 response, as seen in atopic dermatitis, mycosis fungoides, etc. [6]. Thymus and activated-related chemokine (TARC) is one of the chemokines produced by keratinocytes which selectively activate lymphocytes of Th2 subset expressing CCR4 (receptor for TARC) [7]. Accumulating evidence has suggested that these chemokines have primary pathogenic importance in Th2 skin diseases. In order to find the effects of UVB irradiation on the production of TARC, we used a human keratinocyte HaCaT cell line. As assessed by RT-PCR and ELISA, UVB irradiation significantly decreased the expression of TARC mRNA and protein in HaCaT cells stimulated with interferon-γ (IFN-γ) and TNF-α in a dose-dependent manner. The down-regulation of TARC expression may be mediated in part by activation of the particular transcription, signal transducer and activator of transcription 1 (STAT 1), since it has shown that STAT 1 DNA-binding was down-regulated by UVB irradiation. Our results suggest that STAT 1 and other transcription factors play an important biological role in immune system of human skin irradiated by UVB and may support the results of Kolgen et al. [5].In this point of view, UVB irradiation will be a therapeutic tool for skin diseases related to Th2 type reaction, such as atopic dermatitis, mycosis fungoides, etc., although we need to optimize adequately the use of UVB in patients with J-I skin type or those of whom have the episode of severe sun-burn after UVB irradiation.〈section xml:id="abs1-1"〉〈title type="main"〉References1. Pathak, M.A., Nghiem, P. and Fitzpatrick, T.B. Acute and chronic effects on the skin. In: Fitzpatrick's Dermatology in General Medicine, 5th edn (Freedberg, I.M., Eisen, A.Z., Wolf, K., Austen, K.F., Goldsmith, L.A., Katz, S.I. and Fitzpatrick, T.B. eds), pp. 1598–1607. McGraw-Hill, New York (1999).2. Satoh, Y. and Kawada, A. Action spectrum for melanin pigmentation to ultraviolet light, and Japanese skin typing. In: Brown Melanoderma: Biology and Diseases of Epidermal Pigmentation (Fitzpatrick, T.B., Wick, M.M. and Toda, K. eds), pp. 87–95. University of Tokyo Press, Tokyo (1986).3. Araki, K., Nagano, T., Ueda, M., Washio, F., Watanabe, S., Yamaguchi, N. and Ichihashi, M. Incidence of skin cancers and precancerous lesions in Japanese- Risk factors and prevention. J. Epidemiol. 9, S14–S21 (1999).4. Teunissen, M. B., Piskin, G., Nuzzo, S. et al. Ultraviolet B radiation induces a transient appearance of IL-4+ neutrophils, which support the development of Th2 responses. J Immunol. 168, 3732–3739 (2002).5. Kolgen, W., van Meurs, M., Jongsma, M. et al. Differential expression of cytokines in UVB-exposed skin of patients with polymorphous light eruption. Arch. Dermatol. 140, 295–302 (2004).6. Kakinuma, T., Sugaya, M., Nakamura, K., Kaneko, F., Wakugawa, M., Matsushima, K. and Tamaki, K. Thymus and activation-regulated chemokine (TARC/CCL17) in mycosis fungoides: serum TARC levels reflect the disease activity of mycosis fungoides. J. Am. Acad. Dermatol. 48, 23–30 (2003).7. Imai, T., Nagira, M., Tkagi, S. et al. Selective recruitment of CCR4-binding Th2 cells toward antigen-presenting cells by the CC chemokins thymus and activation-regulated chemokine and macrophage-derived chemokine. Int. Immunol. 11, 81–88 (1999).

Notes: Patients with Behcet's disease show an intense delayed hypersensitivity (DH) reaction to a group of streptococcal bacteria. We have attempted to detect deposits of immune complexes and to analyse cytological reactions in the aphthous ulcers and erythema nodosum (EN)-like eruptions. Deposits of IgM and positive fluorescence of anti-streptococcal group D serum were found in vessel walls and sites infiltrated by inflammatory cells. Cytological analysis has revealed that the inflammatory infiltrating cells are mainly composed of activated T-cells and macrophages in association with natural killer cells. These results suggest that DH reactions with antigen-antibody mediated cytotoxicity may play an important role in causing the lesions of Behcet's disease.

Notes: Summary Background Mutations of the patched (Ptc) gene, a developmental regulator implicated in the signalling pathway via sonic hedgehog (Shh) and smoothened (Smo), play an essential pathogenic role in the development of basal cell carcinomas (BCCs). We previously reported the upregulation of Shh signal transducers, including Ptc, Smo and hedgehog-interacting protein, in BCCs. In vertebrates, specific downstream effectors in the Shh signalling pathway include three zinc-finger transcription factors, Gli1, Gli2 and Gli3. Gli1 possesses only an activation domain, while Gli2 and Gli3 contain both activation and repression domains. It remains unclear which of these transcription factors are responsible for the development of BCCs. Objectives To examine the expression pattern of Gli2 mRNA by human BCCs in comparison with those by normal human skin and various skin tumours. Methods We performed quantitative reverse transcriptase–polymerase chain reaction analyses with a series of samples from BCCs, other skin tumours and normal skin. Results We found that Gli2 mRNA expression was enhanced in the BCCs we examined, whereas there was no significant increase in other skin tumours or normal skin. Of four spliced Gli2 isoforms designated Gli2α, β, γ and δ, the expression of Gli2β mRNA was increased the most in BCCs. Conclusions As Gli2β is an isoform spliced at the first splicing site containing a repression domain and consists of an intact activation domain, its overexpression may lead to the upregulation of the Shh signalling pathway, thereby inducing BCCs.

Notes: Epidermal desmogleins with molecular weights of 130/140kDa (Dsg3 or PVA) and 150/160 kDa (Dsg1 or DGI) are recognized by autoantibodies from patients with pemphigus vulgaris (PV) and pemphigus foliaceus (PF), respectively. In order to understand the histogenesis of both types of pemphigus, we studied the expression patterns of Dsgl and Dsg3 during stratification of cultured keratinocytes. Monolayers of cultured normal human keratinocytes demonstrated uniform inter cellular staining with PV sera. The staining pattern was distinct from the focal staining with PF sera observed only in the stratified areas. Both Dsgl and Dsg3 proteins and their mRNA were expressed by the monolayers, whereas no production of Dsg2 (HDGC) mRNA was found. The relative ratio of Dsg3 to the total desmogleins, as determined by density on immunoblotting, decreased as the cultured keratinocytes stratified. In the completely stratified keratinocytes cultured on collagen membrane, Dsgl became predominant, with subsequent reduction of PV antigen expression. The relative decrease of Dsg3 (PVA) during epidermal differentiation might be responsible for the induction of suprabasal acantholysis in PV.

Notes: In order to understand the variety of HTLV-1-associated cutaneous diseases, we studied the cytological profile of HTLV-1-infected T-cell lines established from patients with adult T-cell leukaemia (ATL). Among four CD4+ cell lines, termed 16T(−), 35T(−), MH-1, and KS-2, the 16T(−) cells secreted elevated quantities of IL-4, IL-b and IFN-7, and expressed mRNA for each cytokine in the absence of exogenous stimulation. The 3ST(−) cells secreted IL-6 and a small amount of IFN-7, but not IL-4. The MH-1 and KS-2 cells secreted only 1L-6 in the absence of stimulation, hi response to stimulation with phorbol-12-myristate-13 acetate (PMA), the 16T(−) cells produced more IL-4 and IFN-γ, whereas the 35T(−) and MH-1 cells exhibited increased secretion of IFN-γ, but still no IL-4 or IL-4 mRNA production. Although neither IL-4 nor IFN-γ were found in the culture supernatant of KS-2 cells, the production of IL-4 mRNA was detected by RT PCR. Culture supernatants from the 16T(−) and 35T(−) cells induced the expression of intercellular adhesion molecule-1 (ICAM-1) and HLA-UR by cultured keratinocytes. This response was inhibited by pretreatment of the supernatant with anti-IFN-γ antibodies. These results indicate that some HTLV-1-infected T-cell lines constitutively secrete various cytokines, including biologically active IFN-γ. The diversity of immunobiological functions of the T-cell lines may be related to the variety of clinical features present in ATL patients.