Y. Tateishi

A Novel Active Mouse Model for Bullous Pemphigoid Targeting Humanized Pathogenic Antigen

Bullous pemphigoid (BP), the most common autoimmune blistering disease, is caused by autoantibodies against type XVII collagen (COL17). To establish an active stable BP animal model that demonstrates the persistent inflammatory skin lesions initiated by the anti-human COL17 Abs, we used COL17-humanized (COL17m−/−,h+) mice that we recently produced. First, we generated immunodeficient Rag-2−/−/COL17–humanized mice by crossing Rag-2−/− mice with COL17-humanized mice. Then, splenocytes from wild-type mice that had been immunized by grafting of human COL17-transgenic mouse skin were transferred into Rag-2−/−/COL17–humanized mice. The recipient mice continuously produced anti-human COL17 IgG Abs in vivo and developed blisters and erosions corresponding to clinical, histological, and immunopathological features of BP, although eosinophil infiltration, one of the characteristic histological findings observed in BP patients, was not detected in the recipients. Although the depletion of CD8+ T cells from the immunized splenocytes was found to produce no effects in the recipients, the depletion of CD4+ T cells as well as CD45R+ B cells was found to inhibit the production of anti-human COL17 IgG Abs in the recipients, resulting in no apparent clinical phenotype. Furthermore, we demonstrated that cyclosporin A significantly suppressed the production of anti-human COL17 IgG Abs and prevented the development of the BP phenotype in the treated recipients. Although this model in an immunodeficient mouse does not exactly reproduce the induction mechanism of BP in human patients, this unique experimental system targeting humanized pathogenic Ag allows us to investigate ongoing autoimmune responses to human molecules in experimental animal models.

Successful treatment of severe recalcitrant erosive oral lichen planus with topical tacrolimus

Oral lichen planus (LP) is a severe, painful form of LP, and is often resistant to topical corticosteroid therapy. Recently, open trials demonstrated that topical tacrolimus therapy was effective for the treatment of chronic erosive oral LP. We report two cases with severe recalcitrant erosive oral LP, who dramatically benefited from topical tacrolimus therapy. In case 1, a 64‐year‐old man presented with a 5‐month history of painful erosions on his entire lower lip and buccal mucosa. Physical and histological examination confirmed a diagnosis of LP. He experienced rapid relief from pain and a dramatic improvement was obtained within 5 weeks of topical tacrolimus treatment. No significant irritation was observed and blood tacrolimus level was kept within a safe level (2.5 ng/mL). In case 2, a 68‐year‐old man developed painful erosions on his right lower lip and buccal mucosa 2 months before his arrival at our hospital. Histopathological analysis confirmed a diagnosis of oral LP. He experienced a rapid dramatic improvement of both lesions within 4 weeks of the start of tacrolimus application. No significant irritation or recurrence was observed. Thus, topical tacrolimus is suggested as a well‐tolerated, effective therapy for oral LP.

Blockade of Autoantibody-Initiated Tissue Damage by Using Recombinant Fab Antibody Fragments against Pathogenic Autoantigen

Activation of the complement cascade via the classical pathway is required for the development of tissue injury in many autoantibody-mediated diseases. It therefore makes sense to block the pathological action of autoantibodies by preventing complement activation through inhibition of autoantibody binding to the corresponding pathogenic autoantigen using targeted Fab antibody fragments. To achieve this, we use bullous pemphigoid (BP) as an example of a typical autoimmune disease. Recombinant Fabs against the non-collagenous 16th-A domain of type XVII collagen, the main pathogenic epitope for autoantibodies in BP, were generated from antibody repertoires of BP patients by phage display. Two Fabs, Fab-B4 and Fab-19, showed marked ability to inhibit the binding of BP autoantibodies and subsequent complement activation in vitro. In the in vivo experiments using type XVII collagen humanized BP model mice, these Fabs protected mice against BP autoantibody-induced blistering disease. Thus, the blocking of pathogenic epitopes using engineered Fabs appears to demonstrate efficacy and may lead to disease-specific treatments for antibody-mediated autoimmune diseases.

Wells' syndrome as a manifestation of hypereosinophilic syndrome

SIR, We read with interest the article by Schnider et al. evaluating the long-term efficacy and safety of Botulinum toxin type A (BoNT ⁄ A) treatment in focal hyperhidrosis. The therapy was safe and only minor side-effects, such as transient weakness of finger grip, were observed, in accordance with other authors. Moreover, Naumann and Lowe described only mild compensatory sweating in nontreated areas after axillary BoNT ⁄ A administration while in some patients treated with BoNT ⁄ A for dystonia, generalized transient weakness has been reported, suggesting a mild botulism. We report a first case of generalized muscular weakness associated with signs of systemic cholinergic autonomic impairment in a 25-year-old female patient, weighing 48 kg, who was treated with BoNT ⁄ A for axillary and palmar hyperhidrosis. She was affected by severe palmoplantar and axillary hyperhidrosis that had interfered with her daily life since infancy. On the specific request of the patient and with her informed consent, axillae and hands were treated in the same session; normally, we would use a separate therapeutic approach for the two different sites involved in hyperhidrosis. A total of 1400 U of diluted BoNT ⁄ A (100 U Dysport mL saline solution) were administrated intradermally. The extent of the sweating territories were detected by Minor iodine test and the cutaneous area delineated with a pen. The whole sweating area was divided into squares of about 2 · 2 cm in the axillae and 1Æ5 · 1Æ5 cm on the hands. Fingers were treated both on palmar and dorsal aspects, where the exaggerated sweating was present. The injections were performed with 0Æ05 mL solution for each square reaching a total amount of 500 U for each hand and 200 U for each axilla. The hand injections were preceded by local anaesthetic block of median and ulnar nerves at the wrist, without any complications. Six days after BoNT ⁄ A treatment she began to complain of diffuse asthenia, diplopia, mild bilateral ptosis and severe weakness in finger movements. She also noticed a decrease in lacrimation, salivary production and sweating, without difficulty in intestinal and bladder emptying. Physical examination confirmed the signs of generalized weakness associated with mild cholinergic dysautonomia. A neurophysiological study performed on the legs muscles, distant from the injections sites, excluded neuropathic or muscular disease, while Single Fibre EMG (SFEMG) documented pathological jitters, typical of neuromuscular transmission failure. The Sympathetic Skin Response was absent in recordings from the hands and untreated feet, and cardiovascular reflexes showed a decrease in R–R variation after deep breathing, typical for cholinergic diffuse involvement. Afterwards the patient was controlled weekly. A progressive improvement in strength was observed, but she recovered completely from the BoNT ⁄ A injections only after 2 months. The clinical dysautonomic signs recovered fully after 4 weeks, with the exception of the hands and axillae anhidrosis that remained for a longer time. Despite the side-effects, the patient was fully satisfied with the BoNT ⁄ A therapy and she engaged us for a further treatment when the sweating relapsed. The clinical and neurophysiological data were consistent with a mild but diffuse Botulism–like syndrome, probably related to the high BoNT ⁄ A doses used. Since 1998 we have treated 116 axillae, 112 hands and 23 cheeks for focal hyperhidrosis, with the total BoNT ⁄ A dosage ranging between 25 and 380 U Botox and 100–1200 U Dysport , per session. We have never observed systemic side-effects similar to those described above. In the present patient we used a BoNT ⁄ A amount higher than that used by Schnider et al. for palmar hyperhidrosis (1000 U vs. 460 U Dysport ) and the same for axillary hyperhidrosis (400 U Dysport ). The different amount in the hands is related to the different techniques applied. As our patients reported that treatment localized only in the palms did not improve their quality of life enough (individual questionnaires, unpublished data), we prefer to use a diffuse BoNT ⁄ A distribution on both palms and fingers. In the instructions for drug use, the manufacturers indicate the recommended maximum BoNT ⁄ A dose only for movement disorders (200 U Botox , 1000 U Dysport ). On the other hand, the dose we used is not higher than those applied for spasticity by several authors reaching 600 U and 5000 U for Botox and Dysport , respectively, without relevant side-effects. Moreover, it could be that different modalities of BoNT ⁄ A administration in muscular and cutaneous regions could determine a different rate of systemic side-effects. The numerous intradermal injections and the slight build of our patient could have favoured, in our case, an easier haematogenic systemic spread of BoNT ⁄ A. Therefore, further studies about the safety and efficacy of BoNT ⁄ A are needed for treatment of hyperhidrosis as has been done previously for neuromuscular treatment. With regard to the present data, one should also be careful when using high dosages of BoNT ⁄ A for hyperhidrosis. When more areas are affected, BoNT ⁄ A treatment might be scheduled in different and successive sessions in order to reduce the total amount of toxin injected and to avoid possible generalized side-effects.

Keratosis follicularis squamosa (Dohi) : a follicular keratotic disorder well known in Japan

Keratosis follicularis squamosa (KFS) is a keratinizing disorder, which is well recognized in Japan but rarely reported in other countries. KFS is characterized by asymptomatic small scaly patches with a follicular plug that is scattered on the trunk and thighs. It is easily diagnosed by its characteristic appearance that was originally described in Japanese as ‘lotus leaves on the water’. We report a typical case of KFS and review the mainly Japanese literature. We conclude that KFS is a distinct clinical entity of unknown origin. World‐wide recognition of this disease should further clarify the prevalence and pathogenesis of this skin condition.

A severe and refractory case of anti-p200 pemphigoid resulting in multiple skin ulcers and scar formation.

Anti-p200 pemphigoid is a recently described autoimmune blistering skin disease that is characterized by the presence of autoantibodies against an unidentified 200-kDa dermal autoantigen. Most of the previous cases have been successfully treated using mild-to-moderate immunosuppressive therapies, which resulted in a good prognosis. We report here a severe and refractory case of anti-p200 pemphigoid that developed in a 53-year-old woman, in which blisters led to multiple skin ulcers, followed by severe scar formation. In the present case, methylprednisolone pulse therapy was effective enough to reduce the disease activity.

Recurrence of hydroxyurea-induced leg ulcer after discontinuation of treatment.

Hydroxyurea (HU) is a hydroxylated derivative of urea that has been recognized since 1960 as effective against cancer (1). It is an inhibitor of cellular DNA synthesis, and it promotes cell death in the S phase of the cell cycle through inhibition of the enzyme ribonucleotide reductase (2). The most common indications for HU therapy are chronic myeloid leukaemia and other myeloproliferative disorders (3, 4) such as essential thrombocythemia (5) and polycythemia vera (PV) (6). Cutaneous side-effects, such as alopecia, diffuse hyperpigmentation, scaling, lichen planus-like lesions, poikiloderma, atrophy of the skin and subcutaneous tissues, and nail changes, can occur during the treatment with HU (7–9). The occur-rence of painful leg ulcers represents another rare and incompletely characterized complication that has been described in patients with myeloproliferative diseases receiving high-dose long-term HU treatment (10). While the mode of action of HU on bone marrow elements is well established, its effects on actively proliferating epit-helial cells remain less described (11). Poor response to traditional local and systemic therapy is a typical feature of HU-induced leg ulcers, and discontinuation of the drug is often required to achieve complete wound healing (6, 8). Cessation of the drug usually improves the skin ulcer; although, in some cases, the ulcer remains and additional therapies, such as skin grafting, are needed (12). We report here the first case of a leg ulcer that recurred even after discontinuation of HU treatment. CASe rePorTThe patient was an 82-year-old Japanese male who had been diagnosed with PV 9 years before and had been treated only with phlebotomy and an anti-platelet agent for several years. Due to splenomegaly and elevated blood cell counts, HU therapy was started 3 years ago at a dosage of 1 g daily for a month, followed by 1.0 or 1.5 g daily for 28 months. A good clinical response was achieved. However, the patient developed painful ulcers on the left second toe after two years of HU treatment.He visited our outpatient clinic and was diagnosed with an HU-induced skin ulcer. HU was discontinued, topical application of sulfadiazine silver was performed, an oral antibiotic (cefdinir) was administered, and the ulcer epithelialized. However, a new ulcer appeared on the left lateral malleolar area 46 days after cessation of HU and gradually enlarged in size. The patient was admitted to our hospital for treatment of the ulcer.examination revealed a 48 × 56 mm ulcer with yellow necrotic tissue and marginal erythematous oedema (Fig. 1). Laboratory examination revealed a white blood cell count of 11.6×10

Tumour-like muscular sarcoidosis.

Sarcoidosis is a multisystem granulomatous disease of unknown aetiology with variable manifestations, which may affect virtually any organ. Muscular sarcoidosis is a rare entity, and among this group of muscular lesions, the tumour‐like muscular sarcoidosis subtype is extremely rare. We report on two sarcoidosis cases that presented muscular sarcoid lesions with subcutaneous tumours.

Acquired perforating dermatosis appearing as elastosis perforans serpiginosa and perforating folliculitis

associated with inflammatory lesions. In these cases the lesions were located on the trunk, where the acne lesions were found. Other retinoids such as etretinate and topical retinoids, have also been associated with PG-like lesions. In addition to retinoids, PG-like lesions have been reported with indinavir treatment, an inhibitor of a human immunodeficiency virus (HIV)-1 protease, in up to 5.9% of patients. In these cases the lesions are distributed in the lateral nail folds, most commonly in the toes. It is believed that in this specific location, the disorder is trauma-related. Some homologies between the amino-acid sequences of retinoid acid-binding protein and the catalytic site of HIV-1 protease may explain the cutaneous side-effects of these two drugs. However, the pathogenic mechanism remains unknown. The only previous report of PG-like lesions related to capecitabine treatment was described by Piguet et al. The patient received capecitabine for 4 months and developed lesions in eight of his toes. The lesions resolved 1 month after discontinuation of capecitabine. Although there are some reports describing onycholysis in relation to capecitabine, no further reports of PG-like lesions have been described. Whether there are some similarities between capecitabine and retinoids or indinavir is not known. Dermatologists should be aware of the common cutaneous side-effects of capecitabine, including PG-like lesions.

Diagnosis of Werner syndrome by immunoblot analysis.

Summary Werner syndrome (WS) is caused by mutations in the gene encoding RecQ type DNA helicase (WRN). We report a 53‐year‐old Japanese male with WS who initially presented with skin ulcers on the feet and the left elbow. The patient had a high‐pitched voice, hoarseness, a characteristic bird‐like facial appearance with a beak‐shaped nose, canities and juvenile cataracts. Immunoblot analysis using a monoclonal antibody directed against the WS gene product DNA helicase revealed that the patients leucocytes lacked this particular molecule, confirming the diagnosis of WS. This new immunoblot system therefore enables the diagnosis of WS to be made without the need to undertake more complex mutational analysis.