Daichi Hoshina

Bone marrow transplantation restores epidermal basement membrane protein expression and rescues epidermolysis bullosa model mice

Attempts to treat congenital protein deficiencies using bone marrow-derived cells have been reported. These efforts have been based on the concepts of stem cell plasticity. However, it is considered more difficult to restore structural proteins than to restore secretory enzymes. This study aims to clarify whether bone marrow transplantation (BMT) treatment can rescue epidermolysis bullosa (EB) caused by defects in keratinocyte structural proteins. BMT treatment of adult collagen XVII (Col17) knockout mice induced donor-derived keratinocytes and Col17 expression associated with the recovery of hemidesmosomal structure and better skin manifestations, as well improving the survival rate. Both hematopoietic and mesenchymal stem cells have the potential to produce Col17 in the BMT treatment model. Furthermore, human cord blood CD34+ cells also differentiated into keratinocytes and expressed human skin component proteins in transplanted immunocompromised (NOD/SCID/γcnull) mice. The current conventional BMT techniques have significant potential as a systemic therapeutic approach for the treatment of human EB.

Topical application of anti-angiogenic peptides based on pigment epithelium-derived factor can improve psoriasis

BACKGROUND Psoriasis is a common chronic inflammatory skin disorder with a high prevalence (3-5%) in the Caucasian population. Although the number of capillary vessels increases in psoriatic lesions, there have been few reports that have specifically examined the role of angiogenesis in psoriasis. Angiogenic factors, such as vascular endothelial growth factor (VEGF), may dominate the activity of anti-angiogenic factors and accelerate angiogenesis in psoriatic skin. OBJECTIVE We investigated to identify small peptide mimetics of PEDF that might show anti-angiogenic potential for the topical treatment for psoriasis. METHODS We examined the expression of PEDF in skin by immunohistochemical staining, immunoblotting, and RT-PCR. To identify potential PEDF peptides, we screened peptides derived from the proteolytic fragmentation of PEDF for their anti-proliferative action. Anti-psoriatic functions of these peptides were analyzed using a mouse graft model of psoriasis. RESULTS The specific low-molecular weight peptides (MW<850 Da) penetrated the skin and showed significant anti-angiogenic activity in vitro. Topical application of these peptides in a severe combined immunodeficient mouse model of psoriatic disease led to reduced angiogenesis and epidermal thickness. CONCLUSIONS These data suggest that low-molecular PEDF peptides with anti-angiogenic activity may be a novel therapeutic strategy for psoriasis.

Epidermolysis bullosa acquisita associated with psoriasis vulgaris

Summary We report a case of epidermolysis bullosa acquisita (EBA) associated with psoriasis vulgaris. A 71‐year‐old woman with psoriasis vulgaris developed subepidermal blisters on the extremities. Direct immunofluorescence demonstrated linear deposit of IgG at the basement membrane zone, which bound to the dermal side of normal human skin split with 1 mol/L NaCl. Immunoblot analysis using recombinant full‐length type VII collagen detected a 290‐kDa band, confirming the diagnosis of EBA. A literature search for previous reports found a few cases of EBA associated with psoriasis, and all cases, including our own, presented with widespread inflammatory vesicles and bullae, and responded to conventional therapy with corticosteroids and immunosuppressive agents. This study suggests that western blotting using recombinant full‐length type VII collagen could be useful for diagnosis of EBA, and that EBA associated with psoriasis may have a tendency to be the inflammatory type.

Eccrine porocarcinoma and Bowen's disease arising in a seborrhoeic keratosis

An association between seborrhoeic keratosis (SK) and malignant tumours is considered to be rare. We observed a case of eccrine porocarcinoma and Bowens disease (BD) occurring synchronously, forming one lesion in a SK on the abdomen. It is controversial whether malignant neoplasms arising in SK occur only by chance or if pre‐existing SK plays a role in pathogenesis. This case suggests an implication of pre‐existing SK in the subsequent development of both BD and eccrine porocarcinoma. 

DNA vaccination against macrophage migration inhibitory factor improves atopic dermatitis in murine models

BACKGROUND Atopic dermatitis (AD) is a common chronic inflammatory skin disease. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that has been implicated in the pathogenesis of AD. Recently, we developed a novel DNA vaccine that generates neutralizing endogenous anti-MIF antibodies. OBJECTIVE This study explores the preventive and therapeutic effects of this MIF-DNA vaccine in mouse models of AD. METHODS Two different AD model mice (DS-Nh and NC/Nga) received MIF-DNA vaccination to analyze preventive and therapeutic effects, as assessed by clinical skin scores, histologic findings, and serum IgE levels. RESULTS In murine models of AD, MIF-DNA vaccination prevented the occurrence of the AD skin phenotype. Furthermore, administration of MIF-DNA vaccine to mice that had already developed AD produced a rapid improvement in AD skin manifestation. There were reduced histologic signs of inflammation and lower serum IgE levels in treated mice compared with those seen in control animals. Finally, passive transfer of IgG from MIF-DNA vaccinated mice to AD mice also produced a significant therapeutic effect. These results demonstrate that MIF-DNA vaccination not only prevents the development of AD but also improves the symptoms of pre-existing AD. CONCLUSION Taken together, the induction of an anti-MIF autoantibody response using MIF-DNA vaccination appears to be a useful approach in the treatment of AD.

An infantile case of pityriasis lichenoides et varioliformis acuta.

Such a case is therefore considered to be highly unusual. A number of reports have described no relationship between the clinical presentation in the mothers and the neonates. They also report that antibody titres and clinical presentation in the mothers with PV cannot predict the severity of neonatal PV. In our case, while the mother only had a few oral erosions during her two pregnancies, the neonates presented with skin bullae and erosions at birth. In addition, when comparing the two neonates, the disease condition of the second baby was much more severe than that of the first. Therefore, we consider that our case supports the findings of the reports mentioned above. Regarding the ELISA index values of the neonates, although baby 2 had a lower level of Dsg3, her symptoms were more severe than those of her brother. This suggests that a lower Dsg3 antibody titre in neonates is not necessarily associated with a lower disease severity. Since 1966 there have been 45 reports worldwide of the birth of children from patients with PV, including our two cases. In 18 of these cases, the babies were born with PV lesions. Moreover, in nine cases, the mothers had only mucous membrane lesions, while the babies had some skin lesions. Three other cases have been reported of neonates with PV who had severe skin lesions but whose mothers had no active disease. There are no other reports of siblings with neonatal PV. Our case is therefore considered to be very rare but similar to the cases reported by Campo-Voegeli et al. and Parlowsky et al. In these reports, anti-Dsg3 and Dsg1 IgG ELISA index values were also studied. In both cases, while the mothers had high index values for anti-Dsg3 IgG and anti-Dsg1 IgG, the neonates had a high index value for only anti-Dsg3 IgG, as in our cases. These observations support the findings of previous studies, and suggest that the distribution of Dsg3 in the neonatal epidermis is different from that in the adult epidermis and is more similar to its distribution in the adult mucous membrane. Subcorneal keratinocytes in newborn infants contain both Dsg1 and Dsg3, whereas the suprabasal layers contain much lower Dsg1 levels, with Dsg3 constituting most of the strength of the intercellular desmosomal bridges. This may be why antibody to Dsg3 induced severe blisters in our cases.

Giant dermatofibroma: a rare variant of dermatofibroma preferentially developing on the lower limbs

A 20-year-old man presented to our outpatient clinic with a 3-year history of a slowly growing nodule on his right leg. Physical examination revealed a brown, firm nodule, 50 mm in diameter, which was immobile owing to the adhesion to the subcutaneous tissue (Fig. 1a). The surface of the nodule was moderately hyperkeratotic and partly covered with brown crusts. An initial incisional biopsy demonstrated an irregularly arranged dense proliferation of fibroblast-like cells throughout the dermis and superficial subcutaneous tissue. Magnetic resonance imaging demonstrated invasion close to the fascia of the anterior tibial muscle (Fig. 1b). A simple surgical excision was made for diagnosis and treatment. Histopathological examination revealed a relatively sparse proliferation of fibroblast-like tumour cells without nuclear atypia throughout the entire dermis (Fig. 2a). The overlying epidermis demonstrated moderate hyperkeratosis (Fig. 2b). The tumour cells were loosely arranged within the mature collagen bundles (Fig. 2c) and partially extended into the superficial subcutaneous tissue along the fibrous septa (Fig. 2d). Immunohistochemical examination demonstrated a lack of CD34 expression in the proliferating tumour cells. From the histopathological and immunohistochemical features, a diagnosis of giant dermatofibroma (DF) was made. DF is a benign cutaneous tumour, generally <20 mm in diameter. However, these tumours sometimes enlarge and may be misdiagnosed as malignant tumours, such as dermatofibrosarcoma protuberans (DFSP). Giant DF is a clinical variant of DF, designated by Danckaert and Karassik in 1975 and characterized by its unusually large size. Although there is no clear definition of the size for the diagnosis of giant DF, Requena et al. used a size larger than 35 mm for the diagnosis of giant DF in their study. In previous reports, the size of the tumour ranged from 35 to 120 mm, and almost all the lesions were located on the lower limbs. No recurrence after surgical excision has been reported to date. Distinguishing giant DF from malignant fibrous tumours, especially DFSP, may be difficult, owing to its unusual clinical appearance. Although histopathological examination reveals conventional features of DF in most cases, an incisional biopsy specimen from the tumour may demonstrate architectural features similar to DFSP. In order to distinguish between the two entities of giant DF and DFSP, several reports have suggested that immunohistochemical analysis of CD34 and factor XIIIa expression is useful. However, even these methods could fail to lead to a diagnosis because there may be staining variability among different cases. Focal CD34 reactivity may be demonstrated in some DF cases, whereas some DFSPs uncharacteristically express factor XIIIa, but not CD34. Recently, Cribier et al. reported that immunohistochemical staining of stromelysin 3 (ST3) may be useful for the distinction in such problematic cases. In their study, none of the 40 DFSP cases expressed ST3, while all 40 DF cases, including 10 giant DFs, expressed ST3. In our case, initial incisional biopsy was insufficient to permit a definite diagnosis to be made. Careful histopathological re-evaluation of the surgical specimens revealed that most of the tumour showed the typical histopathological features of DF. In addition, the negative result of immunohistochemical staining with antiCD34 supported the diagnosis of giant DF. We suggest that a thorough histopathological examination of large tissue samples from the tumour, together with immunohistochemical staining, is recommended for the correct diagnosis of giant DF. CP D

Establishment of a novel experimental model of human angiosarcoma and a VEGF-targeting therapeutic experiment

BACKGROUND Angiosarcoma is one of the most life-threatening neoplasms with strong resistance to conventional chemotherapy/radiotherapy; consequently, alternative therapeutic agents are urgently required. One factor in delaying the therapy development is the limitation of experimental models. OBJECTIVE We established a novel experimental angiosarcoma model. METHODS From surgically resected tissue, human AS cell line was established. Using xenograft of AS cell line, we performed therapeutic experiments with the anti-human VEGF Ab or the receptor tyrosine kinase inhibitor. RESULTS First we generated an angiosarcoma cell line, HAMON (human angiosarcoma, monoclonal), which expresses CD31 and produces tumors in immunodeficient mice. HAMON expresses VEGFR2 and that exogenous VEGF leads to HAMON proliferation in vitro. Anti-human VEGF Ab bevacizumab treatment failed to suppress HAMON proliferation in vitro and in vivo. Furthermore, the receptor tyrosine kinase inhibitor sunitinib did not suppress HAMON proliferation in vitro. Similarly, in in vivo therapeutic experiments, even high doses of sunitinib failed to inhibit tumor growth. Finally, we checked whether compensatory activation of VEGF signaling occurred after sunitinib addition. VEGF protein secretion, VEGF mRNA synthesis and VEGFR2 phosphorylation all were unaffected in HAMON after sunitinib treatment. CONCLUSION A novel in vitro and in vivo experimental model of human angiosarcoma has been successfully established. With this model, we were able to perform therapeutic experiments. In addition, our angiosarcoma cell line, HAMON, is quite useful for identifying key molecules in angiosarcoma.

MUC5AC expression correlates with invasiveness and progression of extramammary Paget's disease

Patients with in situ extramammary Pagets disease (EMPD) tend to have a good prognosis, although dermal invasion and metastasis are associated with significantly increased morbidity and mortality. Previous studies have addressed mechanisms underlying the EMPD pathogenesis; however, no molecular markers that reflect invasiveness or progression have been established.

Loss-of-function mutations in the gene encoding filaggrin underlie a Japanese family with food-dependent exercise-induced anaphylaxis.

Food‐dependent exercise‐induced anaphylaxis (FDEIA) is a serious food allergy in which anaphylaxis develops when exercise is performed within several hours after food intake. The precise mechanism underlying allergic sensitization in FDEIA has been an important issue but remains poorly understood.