Yukio Yamashina

8-Methoxypsoralen plus UVA induces the 72-kDa heat shock protein in organ-cultured normal human skin

Abstract The proteins induced by heat and other stressors, called heat shock proteins (HSP) or stress proteins, are considered to play a general role in protection from cellular injury. Exposure to UVA (320400 nm) following application of 8‐methoxypsoralen (8‐MOP), termed PUVA is commonly used in the field of dermatology. In order to understand the induction of HSP in PUVA‐treated human skin, indirect immunofluorescence using a monoclonal antibody specific for the 72 kDa HSP (HSP 72) was carried out in organ‐cultured normal human skin that was treated with PUVA. When the organ‐cultured skin was treated at 37°C for 1 h with 8‐MOP at a final concentration of 10 or 100 μg/mL and exposed to UVA (51.3 kJ/m2), nuclear immunofluorcscence of HSP 72 was detected in the epidermal cells 12 h after UVA irradiation. In contrast, the induction of HSP 72 was not detected either by UVA irradiation or 8‐MOP treatment. These results suggest that PUVA treatment is one of the stressors for human skin, and DNA damage caused by PUVA induces HSP 72.

Polymorphisms of HLA-DR and -DQ genes in Japanese patients with bullous pemphigoid.

Bullous pemphigoid (BP), an autoimmune skin disease of the elderly, is mediated by autoantibodies that bind to hemidesmosomes of epidermal basal cells. This study investigated BP‐associated HLA‐DR and ‐DQ genes among Japanese patients. We analyzed HLA‐DR and ‐DQ genes among 23 Japanese BP patients based on the polymerase chain reaction‐restriction fragment length polymorphism. Eighteen of these 23 patients (78%) carried at least one allele of HLA‐DRB1*04 or DRB1*1101, with significant increases in HLA‐DRB1*04 (*0403, *0406)/DQA1*0301/DQB1*0302 and DRB1*1101/DQA1*0505/DQB1*0302 haplotypes as well as the individual alleles DRB1*1101 and DQB1*0302 (corrected p<0.05 for each comparison), when compared to control subjects. These data differ from the accepted DQB1*0301 (DQ7) association with the same disease among Caucasians. These findings indicate that different HLA class II haplotypes genetically influence susceptibility to BP among different ethnic groups. Our findings, together with previous reports on Caucasian patients with the pemphigoid group of bullous diseases, suggest that HLA‐DRB1 molecules might participate in the regulation of autoimmune responses to BP antigens.

Genotyping for HLA‐A, B and C alleles in Japanese patients with pemphigus: prevalence of Asian alleles of the HLA‐B15 family

Summary Background  There have been only limited reports on major histocompatibility complex class I antigens in pemphigus.

Epidermolysis bullosa acquisita with oesophageal stenosis

Summary Epidermolysis bullosa acquisita (EBA) is a rare acquired subepidermal blistering disorder associated with autoimmunity to type VII collagen. Although the full clinical spectrum of EBA is still being defined, it is now known that EBA has greater clinical heterogeneity than previously suggested. We describe a patient with EBA which closely approximated the severity of the recessive form of dystrophic epidermolysis bullosa.

UVB irradiation reduces the expression of pemphigoid antigens in organ-cultured normal human skin

Pemphigus and bullous pemphigoid (BP) are autoimmune bullous diseases of the skin and mucous membranes. Although the aetiology of pemphigus and BP has not been completely determined, there have been some reports on the factors inducing these diseases [1, 4, 17]. Ionizing radiation [6, 11] and ultraviolet (UV) radiation have been recognized as factors inducing pemphigus or BP [2, 3, 9, 15]. However, to the best our knowledge, the effects of UV radiation on the antigens of pemphigus and BP of human skin at the organ level have not been reported. In the present study, we examined the effects of UVB irradiation on the expression of pemphigus and pemphigoid antigens in organ-cultured normal human skin by an indirect immunofluorescence (IF) method using the sera from patients with pemphigus, pemphigoid, or epidermolysis bullosa acquisita (EBA). Serum samples were obtained from patients diagnosed clinically, histologically and immunologically as having pemphigus vulgaris (PV) or pemphigus foliaceus (PF). The indirect IF method using normal human skin as substrate revealed the titres of circulating anti-intercellular substance antibodies of sera from patients with PV and PF to be 1:40 and 1:640, respectively. Serum samples were also obtained from patients diagnosed as having BP of EBA. Using 1 M sodium chloride-split skin as substrate, a serum sample from the BP patient produced an epidermal IF pattern at the basement ,membrane zone (BMZ), and a serum sample from the ~EBA patient showed a dermal IF pattern at the BMZ [12]. The indirect IF method using normal human skin as substrate revealed the titre of anti-BMZ antibodies of these serum samples to be 1 : 160. Normal human skin samples were obtained during skin surgery from the back of a 31-year-old male patient

Pemphigus Foliaceus Associated with Acanthosis Nigricans-like Lesions and Hepatocellular Carcinoma

A 54-year-old man was referred to our department for evaluation of crusting and blistering skin lesions. Five months previously the skin lesions had begun with mild pruritic, erythematous, and eroded eruption in the axillae, subsequently spreading to the scalp, face, trunk, and extremities. Three months later, these lesions developed into hyperpigmented and hyperkeratotic plaques. Physical examination revealed small flaccid bullae and scaly, crusted, hyperpigmented, verrucous skin lesions varying in size from a few millimeters to a few centimeters on the scalp, face, trunk, and extremities. These skin lesions were prominent in the axillae and groin (Fig. 1). The Nikolsky sign was positive; however, there was no involvement in the mucous membranes. The results of the following laboratory studies were negative or within normal limits: complete blood cell count, urinalysis, total serum proteins, serum electrolytes, serum protein electrophoresis, serum immunoglobulin and complement levels, LE test, DNA test, a-fetoprotein and HBs Ag. Chest x-ray and ECG were normal. Liver function tests disclosed chronic hepatitis. A biopsy specimen obtained from an erythematous, vesicular lesion showed superficial acantholysis with cleft formation at or near the granular layer (Fig. 2). A biopsy specimen obtained from a verrucous lesion on the right axilla showed basket-weave hyperkeratosis, parakeratosis, papillomatosis, and slight acanthosis (Fig. 3). A moderate mononuclear cell infiltrate was present in the papillary and upper reticular dermis. These histologic features resembled those of acanthosis nigricans. Direct immunofluorescence microscopy of an erythematous vesicular lesion showed intercellular depositions of IgG and C3 throughout the epidermis; however, a verrucous lesion showed intercellular deposition of C3. Indirect immunofluorescence studies of the serum using normal human skin as substrates demonstrated circulating intercellular antibodies at a titer of 1:20. The diagnosis of pemphigus foliaceus was confirmed. Treatment was initiated with 5.0 mg of oral betamethasone per day. This produced suppression of new lesions, and apparent clinical remission was observed after 1 week.

Antigen specificities of antibasement membrane zone antibodies: immunofluorescence and Western immunoblotting studies.

SummaryTo clarify the antigen specificities of autoantibodies in sera and blister fluids from patients diagnosed as bullous pemphigoid (BP) by routine histology and immunofluorescence (IF) methods, indirect IF studies using the salt split-skin technique were performed. In addition, to detect the BP antigen(s) in human epidermal extracts, Western immunoblotting analyses were carried out. Of 41 sera, 39 (95%) showed a linear pattern of fluorescence along the epidermal side of the separation. Two (5%) sera showed a linear pattern of fluorescence along the dermal side. Blister fluids produced IF staining patterns identical with those of serum samples. These fluorescence patterns were not related to the BP antigen expression of the skin used as substrates. In Western immunoblotting analyses, selected sera showing an epidermal pattern on separated skin primarily reacted with 240 kD, 220 kD, 180 kD, and 150 kD proteins extracted from normal human epidermis. Two sera showing a dermal pattern on separated skin revealed no specific bands. The protein bands recognized by blister fluids were indentical with those of serum samples. These results indicated that blister fluids are also available in immunological analysis, and that BP antibodies have more than one antigenic specificity. Moreover, it is suggested that differential diagnosis between BP and other bullous diseases may be more important than previously recognized, particularly in patients with epidermolysis bullosa acquisita (EBA).

Annular Elastolytic Giant Cell Granuloma: An Unusual Case with Lesions Arising in Non-sun-exposed Areas

A 70‐year‐old man with a 2‐year history of annular elastolytic giant cell granuloma associated with diabetes mellitus was reported. The lesions mainly developed in non‐sun‐exposed areas. Histologic examination revealed phagocytosis of elastic fibers by histiocytic cells. Immunoperoxidase staining for lysozyme disclosed positive reactivity within the cytoplasm of these histiocytic cells. Electron microscopic study also showed elastic fibers and numerous lipid‐like substances in the cytoplasm of these cells. These findings indicate high phagocytolytic activity by these infiltrating cells. In our case, actinic damage was not considered to be a primary causative factor, and a possible pathogenesis was also discussed.

Fixed Drug Eruption Due to Pipemidic Acid

A 71‐year‐old woman with fixed drug eruption caused by pipemidic acid is reported. The patient developed typical lesions on rechallenge with pipemidic acid, but not with nalidixic acid, an analogue of pipemidic acid.

Melanin reduces ultraviolet-induced DNA damage formation and cell killing rate in cultured human melanoma cells

Epidermal melanin pigment is believed to prevent development of ultraviolet (UV)-induced skin cancer by shielding cell nuclei and reducing DNA damage formation. It has not been experimentally proved, however, whether melanin reduces UV-induced DNA damage, because published experiments have been inconclusive. The present study was carried out to determine whether intracellular melanin protected cultured cells against UV-induced DNA damage and killing. Three human melanoma cell lines containing different amounts of melanin were used. Absorption spectrum, subcellular localization of melanin, and melanin concentration were examined in the three cell lines. Two types of DNA damage, cyclobutane pyrimidine dimers and (6-4)photoproducts, were detected by an enzyme-linked immunosorbent assay (ELISA) with monoclonal antibodies specific for these photolesions. We found that melanin reduced the induction rates of both types of DNA damage in pigmented cells irradiated with low doses of UV in a melanin concentration-dependent manner. Almost no differences in repair capacity for the two types of photolesions were observed among the three melanoma cell lines. We also found that the more highly melanotic melanoma cell lines were more UV resistant than the less melanotic melanoma cell lines. These results suggest that intracellular melanin plays an important role in preventing UV-induced cell killing by reducing the formation of two types of DNA damage.