Takenobu Yamamoto

Hydroa Vacciniforme Is Associated with Increased Numbers of Epstein–Barr Virus–Infected γδT Cells

Hydroa vacciniforme (HV) is a rare photosensitivity disorder of childhood associated with Epstein-Barr virus (EBV)(+) T-cell infiltration. We have summarized clinical manifestations of HV, and analyzed EBV(+) T-cell subsets as well as EBV DNA load in lymphocyte fractions, in comparison with hypersensitivity to mosquito bites (HMB), an EBV-associated T/natural killer (NK) lymphoproliferative disorder. We found that 31 of 33 (93.9%) HV lesions were composed of EBV(+) T cells and reactive EBV(-) cytotoxic T cells, without significant CD56(+) cell infiltration, whereas many CD56(+) cells were present in 8 of 9 (88.9%) HMB lesions. Of 13 (20.6%) HMB patients with or without HV, 12 (92.3%) showed increased percentages (>32%) of NK cells in the peripheral blood, whereas in the 16 patients with HV alone, 14 (87.5%) showed no increase. Of the 11 HV patients, 10 (90.9%) had increased percentages (>5%) of circulating γδT cells, with a mean value of 15.7 ± 2.9%, and the γδT-cell fractions contained larger amounts of EBV DNA than non-γδT-cell fractions. A triple-labeling method revealed that all three HV patients examined had increased percentages of EBER(+), T-cell receptor (TCR)γδ(+), and TCRαβ(-) cells. Our observations indicate that HV is associated with increased numbers of EBV(+) γδT cells, whereas HMB is associated with EBV(+) NK cells.

Pemphigus vegetans with IgG and IgA antidesmoglein 3 antibodies

SIR, Pemphigus vegetans is an uncommon variant of pemphigus that is characterized by vegetating erosions on the intertriginous area. Direct immunofluorescence (DIF) reveals IgG deposition on keratinocyte cell surfaces in the epidermis in all cases, usually associated with C3 deposition. A few case reports of pemphigus vegetans demonstrated IgA deposition on keratinocyte cell surfaces, although the nature of the IgAclass antibodies remains to be determined. We describe a patient with pemphigus vegetans who had both IgG and IgA antidesmoglein (Dsg) 3 antibodies. A 67-year-old Japanese man visited our hospital in August 2003 because of a 2-month history of pustules and erosions appearing on his face, axillae and groins. The skin lesions extended to the abdomen, buttocks and scalp. He had had a gastric ulcer and cerebral infarction at the age of 58 and 61 years, respectively, and he was treated with an antihypertensive drug. Cutaneous examination revealed pustules and erosions on the verrucous plaques in the above-mentioned areas (Fig. 1). Aphthae and white plaques were seen in the oral mucosa and soft palate. Laboratory tests showed anaemia and hypoproteinaemia. The patient’s C-reactive protein level was 3Æ3 mg dL (normal < 0Æ3), and his serum IgA level was 411 mg dL (normal 110–424). Other routine tests were within normal limits. Skin biopsy from the inguinal lesion showed marked acanthosis, suprabasal acantholysis in focal areas and large intraepidermal abscesses composed of many eosinophils (Fig. 2). A dense infiltrate with mixed cells of eosinophils, neutrophils and lymphocytes was observed in the upper dermis. DIF revealed the deposition of IgG, IgA and C3 on keratinocyte cell surfaces in the epidermis. Indirect immunofluorescence for IgG, IgA, IgM and C3 was negative in each case. Immunoblotting using human epidermal extracts showed no specific binding of IgG or IgA from the patient’s serum. The IgG enzyme-linked immunosorbent assay (ELISA) index values of anti-Dsg1 and anti-Dsg3 antibodies were 5Æ2 and 51Æ2 (cut-off value 20), respectively, determined by MESACUP desmoglein test ‘Dsg1’ and ‘Dsg3’ (MBL, Nagoya, Japan). We further performed ELISA for detecting IgA anti-Dsg1 or anti-Dsg3 antibodies using the same plates as described above and horseradish peroxidase-conjugated rabbit polyclonal antihuman IgA antibody (Dako, Glostrup, Denmark). We prepared 20 serum samples from normal individuals (age 59 ± 16Æ6 years) following informed consent to set a cut-off value for the ELISA. The mean ± SD of the normal control samples on ELISA for IgA anti-Dsg1 and anti-Dsg3 antibodies was 0Æ095 ± 0Æ014 and 0Æ106 ± 0Æ029, respectively. To exclude the background levels of normal sera, we set the cutoff value of 0Æ200 for Dsg1 and 0Æ250 for Dsg3. The values in the patient’s sera before therapy were 0Æ123 (negative) for Dsg1 and 0Æ900 (positive) for Dsg3. We also performed a novel ELISA using baculovirusexpressed human desmocollins 1–3, as reported previously. Neither IgG nor IgA was detected in the desmocollin ELISAs. The patient was hospitalized, and treated with oral prednisolone 20 mg daily, but no improvement was observed after 10 days of treatment. Therefore, treatment with a combination of oral prednisolone 30 mg daily and dapsone 75 mg daily was started. This regimen resulted in healing of the verrucous lesions within 3 weeks. The doses of prednisolone and dapsone were tapered to 20 mg and 50 mg daily, A

Cathelicidin antimicrobial peptide LL‐37 augments interferon‐β expression and antiviral activity induced by double‐stranded RNA in keratinocytes

Cathelicidin antimicrobial peptide LL‐37 has the capacity to kill a wide range of microbes and to modify host immunity. Recently, our group observed that the activation of keratinocytes by LL‐37 and DNA greatly increases interferon (IFN)‐β through Toll‐like receptor (TLR)9. However, the effect of LL‐37 on the induction of IFN‐β through TLR3, a sensor of double‐stranded (ds) RNA, in keratinocytes is not well known.

Interferon-Gamma Enhances TLR3 Expression and Anti-Viral Activity in Keratinocytes

Toll-like receptors (TLRs) recognize specific microbial products in the innate immune response. TLR3, a double-stranded RNA sensor, is thought to have an important role in viral infections, but the regulation of TLR3 expression and its function in keratinocytes are not fully understood. Here we show the Th1 cytokine IFN-γ increased the TLR3 expression via STAT1 in cultured normal human epidermal keratinocytes (NHEKs). Co-stimulation with IFN-γ and the TLR3 ligand poly (I:C) synergistically increased the expression of IFN-β, IL-6, IL-8, and human β-defensin-2 in NHEKs compared with poly (I:C) or IFN-γ alone. These synergistic inductions were significantly inhibited by an endosomal acidification inhibitor, chloroquine, and by TLR3 siRNA. Co-stimulation with IFN-γ and poly (I:C) also significantly enhanced the anti-viral activity against herpes simplex virus type-1 in NHEKs compared with poly (I:C) or IFN-γ alone. In addition to the in vitro findings, an immunohistochemical analysis revealed IFN-γ-positive cells surrounding herpetic vesicles. These findings indicate that IFN-γ might contribute to the innate immune response to cutaneous viral infections by enhancing TLR3 expression and function in keratinocytes.

Dendritic cell subsets and immunological milieu in inflammatory human papilloma virus-related skin lesions

BACKGROUND Human papilloma virus (HPV)-related warts persist, evading host immune surveillance, but sometimes disappear with inflammation. OBJECTIVES To elucidate the immune evasion mechanisms of HPV, we have examined the density, dynamics, and subsets of dendritic cell (DC) types in non-inflammatory or inflammatory HPV-related skin lesions such as warts and Bowens disease (HPV-Bowen), and compared the epidermal expression levels of macrophage inflammatory protein (MIP)-3α and E-cadherin. METHODS The expression of various DC markers, MIP-3α, and E-cadherin in the tissue samples obtained from patients with warts, HPV-Bowen and HPV-unrelated skin diseases was evaluated by immunohistochemistry. MIP-3α gene expression levels were examined in warts and HPV-Bowen by in situ hybridization (ISH) and real-time quantitative polymerase chain reaction (RT-qPCR). RESULTS The numbers of Langerhans cells (LCs) and the expression levels of MIP-3α and E-cadherin were decreased in non-inflammatory warts and HPV-Bowen, as compared with normal skin. Both epidermal LCs and MIP-3α expression reappeared in inflammatory warts, associated with dermal infiltrates composed of many cytotoxic T cells and various subsets of DCs, while cellular infiltrates in HPV-Bowen contained many B cells and plasma cells with sparse infiltration of DCs. The upregulation of MIP-3α gene expression was confirmed in the inflammatory warts and HPV-Bowen by ISH and RT-qPCR. CONCLUSIONS The depletion of LCs in the non-inflammatory warts and HPV-Bowen is associated with a down-regulation of expression levels of MIP-3α and E-cadherin in the lesional keratinocytes. MIP-3α expression is upregulated in lesional keratinocytes of inflammatory warts, with the subsequent recruitment of various DC subsets and cytotoxic T cells, whereas plasma cell-rich infiltration was induced in HPV-Bowen.

Ichthyosiform eruptions in association with primary cutaneous T-cell lymphomas

Background  Malignant lymphoma is occasionally complicated by ichthyosiform eruptions.

Poikilodermatous mycosis fungoides with a CD8+ CD56+ immunophenotype: a case report and literature review.

Mycosis fungoides (MF) represents the most common type of cutaneous lymphoma. MF shows varieties in both its clinical presentation and immunophenotype. We herein report one case of poikilodermatous MF with a CD8+ CD56+ immunophenotype and present a literature review. A 20‐year‐old Japanese woman presented with a 10‐year history of multiple poikilodermatous and reddish or brownish patches with mild pruritus on the chest, abdomen, back, buttock and thighs. Histopathologically, small‐ to medium‐sized atypical lymphocytes infiltrated into the epidermis, indicating epidermotropism, along the basal layer, and distributed in band‐like appearance in the papillary dermis. Immunohistochemically, atypical lymphocytes expressed CD3, CD8, CD56, T‐cell intracellular antigen (TIA)‐1, granzyme B and beta F1 but lacked expression of CD4, CD20, CD30 and Epstein‐Barr virus (EBV) latent membrane protein 1. An EBV‐encoded small non‐polyadenylated RNA‐1 (EBER‐1) signal was not detected. On the basis of these findings, the diagnosis of CD8+ CD56+ MF was established. Poikilodermatous MF with a CD8+ CD56+ immunophenotype, as presented herein, is extremely rare. Although further investigation is needed to fully clarify the nature of this aberrant phenotype of MF, we stress that it is important to recognize this rare immunophenotype of MF to distinguish it from aggressive cytotoxic cutaneous lymphomas.

Survival rates and prognostic factors of Epstein-Barr virus-associated hydroa vacciniforme and hypersensitivity to mosquito bites.

Epstein‐Barr virus (EBV)‐associated T/natural‐killer lymphoproliferative disorders form a group of diseases that includes classical and systemic hydroa vacciniforme (HV) and hypersensitivity to mosquito bites (HMB). Patients with systemic HV (sHV) and HMB often have a poor prognosis, although little is known about the prognostic factors.

A prospective analysis of anti-desmoglein antibody profiles in patients with rheumatoid arthritis treated with thiol compounds

BACKGROUND Drug-induced pemphigus is mainly caused by drugs containing sulfhydryl (thiol) groups in their molecules. OBJECTIVES To understand the serial alteration of anti-desmoglein (Dsg) antibody profile in patients with rheumatoid arthritis (RA) receiving thiol compounds. METHODS Anti-Dsg1 or -Dsg3 antibodies were analysed twice in a 1.6-year interval, in the same series of RA patients. RESULTS Eleven of 204 serum samples (5.4%) and 6 of 139 samples (4.3%) from the same RA group showed a positive reaction against Dsg1 or Dsg3 in the first and second screening tests, respectively. The positive rates were higher than those in patients with collagen diseases including systemic lupus erythematosus, Sjögren syndrome, mixed connective tissue disease, and systemic sclerosis. In comparison with the results in the first and second screening tests, one RA patient newly gained anti-Dsg3 antibody, and at least 4 patients lost the antibodies in 1.6 years. Three patients produced antibodies to Dsg1 and/or Dsg3 in a similar fashion as did in the first screening tests. Only one RA serum sample exhibited an intercellular reactivity to human skin or monkey esophagus by immunofluorescence, and another sample bound to a 130 kDa protein suggestive of Dsg3 by immunoblotting. Most anti-Dsg antibodies in RA patients recognized EDTA-resistant epitopes of Dsg different from EDTA-sensitive epitopes recognized by pemphigus sera. CONCLUSION RA patients receiving any of the thiol compounds may gain autoantibodies to non-conformational epitopes of either Dsg1 or Dsg3, and that such autoantibodies alone are not capable of inducing acantholysis.

Diversity of Epstein-Barr virus BamHI-A rightward transcripts and their expression patterns in lytic and latent infections.

Epstein-Barr virus (EBV) BamHI-A rightward transcripts (BARTs; also designated complementary strand transcripts or CSTs) have been demonstrated to contain several splicing forms in EBV-infected cells. To date, however, little is known about the actual full-length splicing form and its functions. In the present study, we proved that six forms of BARTs were present in EBV-positive cell lines and various tissue specimens with different EBV infection patterns. Of the BART-encoded genes, mRNA of four major splicing forms, including BARF0, RPMS1, RPMS1A and A73, were expressed in all EBV-infected cells. On the other hand, mRNA of two minor splicing forms, RK-BARF0 and RB3, was rarely detected, or if at all, at very low expression levels. Both RPMS1A and RPMS1 mRNA was transcribed at higher levels in EBV-infected cells. In particular, RPMS1 mRNA was expressed abundantly in epithelial carcinoma cells, including gastric carcinoma and nasopharyngeal carcinoma, in association with a lytic infection signal, BZLF1 mRNA. The four major splicing forms were expressed much less in B-cell lines with an integrated EBV genome than in those with episomal EBV genomes. These data indicate that at least six splicing forms can be expressed by EBV-infected cells or tissues, although the expression patterns or levels differ for different infection states such as lytic and latent infections.