Elevated expression of interleukin-6 (IL-6) and serum amyloid A (SAA) in the skin and the serum of recessive dystrophic epidermolysis bullosa: Skin as a possible source of IL-6 through Toll-like receptor ligands and SAA.

The effect of persistent skin inflammation on extracutaneous organs and blood is not well studied. Patients with recessive dystrophic epidermolysis bullosa (RDEB), a severe form of the inherited blistering skin disorder, have widespread and persistent skin ulcers, and they develop various complications including anaemia, hyperglobulinaemia, hypoalbuminaemia and secondary amyloidosis. These complications are associated with the bioactivities of IL-6, and the development of secondary amyloidosis requires the persistent elevation of serum amyloid A (SAA) level. We found that patients with RDEB had significantly higher serum levels of IL-6 and SAA compared to healthy volunteers and patients with psoriasis or atopic dermatitis. Both IL-6 and SAA were highly expressed in epidermal keratinocytes and dermal fibroblasts of the skin ulcer lesions. Keratinocytes and fibroblasts surrounding the ulcer lesions are continuously exposed to Toll-like receptor (TLR) ligands, pathogen-associated and damage-associated molecular pattern molecules. In vitro, TLR ligands induced IL-6 expression via NF-κB in normal human epidermal keratinocytes (NHEKs) and dermal fibroblasts (NHDFs). SAA further induced the expression of IL-6 via TLR1/2 and NF-κB in NHEKs and NHDFs. The limitation of this study is that NHEKs and NHDFs were not derived from RDEB patients. These observations suggest that TLR-mediated persistent skin inflammation might increase the risk of IL-6-related systemic complications, including RDEB.

Updated guidelines for chronic active Epstein-Barr virus disease.

Chronic active Epstein-Barr virus disease (CAEBV), formerly named chronic active Epstein-Barr virus infection, is characterized by systemic inflammation and clonal proliferation of Epstein-Barr virus (EBV)-infected T or NK cells. As CAEBV is a potentially life-threatening illness, appropriate diagnosis and therapeutic interventions are necessary for favorable clinical outcomes. Substantial evidence regarding the pathogenesis and treatment of CAEBV has been accumulated since previous guidelines for the diagnosis of CAEBV were proposed. To reflect this evidence, we updated the guidelines for the diagnosis and treatment of CAEBV to improve clinical management of the disease. The details of the updated guidelines are presented in this report. Diagnosis of CAEBV now requires confirmation of a high copy number of EBV genome and EBV-infected T or NK cells. An EBV DNA load ≥ 10,000 IU/mL in whole blood is proposed as the diagnostic cutoff value for CAEBV in this updated guideline. A standard treatment approach for CAEBV has not been established, and hematopoietic stem cell transplantation (HSCT) is considered the only curative treatment. Chemotherapy can be administered to control disease activity before HSCT.

Coexpression of natural killer cell antigens by T-cell large granular lymphocytes in hydroa vacciniforme lymphoproliferative disorder and the involvement of Vδ1 + epithelial-type γδT cells.

Hydroa vacciniforme lymphoproliferative disorder (HV-LPD) is a cutaneous variant of chronic active Epstein-Barr virus disease. We examined the coexpression of T- and natural killer (NK)-cell antigens in five patients with classic HV (cHV) and five with systemic HV (sHV). T-cell receptor (TCR) repertoire analysis was performed with high­throughput sequencing. All five cHV patients had increased γδT cells (> 5%), whereas five sHV patients showed γδT- and αßT-cell dominance in two patients each, and a mixture of abnormal γδT and αßT cells in one. Circulating CD3 + T cells expressed CD16/CD56 at 7.8-42.3% and 1.1-9.7% in sHV and cHV, respectively. The percentage of CD16/CD56 + T cells was higher in the large granular lymphocyte or atypical T-cell fractions in sHV, but no TCR Vα24 invariant chain characteristic of NKT cells was detected. Considerable numbers of CD3 + cells expressing CD56 were observed in sHV skin infiltrates. Of the circulating γδT cells tested, TCR Vδ1 + cells characteristic of the epithelial type of γδT cells were dominant in two sHV cases. Thus, atypical αßT and γδT cells in HV-LPD can express NK-cell antigens, such as CD16 and CD56, and Vδ1 + epithelial-type γδT cells are a major cell type in some HV-LPD cases.

Diagnostic and disease severity determination criteria for hydroa vacciniforme lymphoproliferative disorders and severe mosquito bite allergy.

Hydroa vacciniforme lymphoproliferative disorder (HV-LPD) and severe mosquito bite allergy (SMBA) are both cutaneous forms of Epstein-Barr virus (EBV)-associated T/natural killer (NK) cell LPDs and are closely related to chronic active EBV disease (CAEBV) and EBV-associated hemophagocytic lymphohistiocytosis (EBV-HLH). HV-LPD is further divided into classic HV, a benign subtype mediated by EBV-positive γδT cells, and systemic HV, another life-threatening subtype mainly associated with EBV-positive αßT or γδT cells. The vast majority of patients with SMBA have increased numbers of EBV-infected NK cells in the blood. Clinical symptoms of HV-LPD and SMBA often overlap in the same patient and may progress to more serious disease conditions equivalent to the systemic form of CAEBV. To define the disease spectrum of HV-LPD and SMBA, we propose the diagnostic criteria and the determination criteria for disease severity. The proposed diagnostic criteria are consistent with those for CAEBV and EBV-HLH in the guidelines for the management for CAEBV and related disorders 2023.

Rituximab therapy for intractable pemphigus: A multicenter, open-label, single-arm, prospective study of 20 Japanese patients.

This was a multicenter clinical trial of rituximab, a chimeric monoclonal IgG antibody directed against CD20, for the treatment of refractory pemphigus vulgaris and pemphigus foliaceus. In total, 20 patients were treated with two doses of rituximab (1000 mg; 2 weeks apart) on days 0 and 14. The primary end point was the proportion of patients who achieved complete or partial remission on day 168 following the first rituximab dose. Of the 20 enrolled patients, 11 (55%) and four (20%) achieved complete and partial remission, respectively; therefore, remission was achieved in a total of 15 patients (75.0% [95% confidence interval, 50.9%-91.3%]). It was demonstrated that the remission rate was greater than the prespecified threshold (5%). In addition, a significant improvement in clinical score (Pemphigus Disease Area Index) and decrease in serum anti-desmoglein antibody level were observed over time. Four serious adverse events (heart failure, pneumonia, radial fracture, and osteonecrosis) were recorded in two patients, of which only pneumonia was considered causally related with rituximab. The level of peripheral blood CD19-positive B lymphocytes was decreased on day 28 after rituximab treatment and remained low throughout the study period until day 168. Our results confirm the efficacy and safety of rituximab therapy for refractory pemphigus in Japanese patients.

Analysis of clonality in cutaneous B-cell lymphoma and B-cell pseudolymphoma using skin flow cytometry: Comparison of immunophenotyping and gene rearrangement studies.

To identify clonal neoplastic cells in skin affected by B-cell lymphoma using skin flow cytometry (FCM) techniques, we investigated light-chain restriction using skin FCM with clonality assessed by polymerase chain reaction and light-chain restriction by in situ hybridization (ISH). We retrospectively analyzed 16 cases of B-cell lymphoma with cutaneous involvement: primary cutaneous diffuse large B-cell lymphoma, leg type (pcDLBCL-LT) (n = 7), DLBCL-not otherwise specified (DLBCL-NOS) (n = 6), primary cutaneous follicle center lymphoma (pcFCL) (n = 1), and follicular lymphoma (n = 2), as well as cutaneous B-cell pseudolymphoma (n = 9). Results of skin FCM light-chain restriction analyses were compared with immunoglobulin H (IgH) gene rearrangement and κ/λ ISH findings. Skin FCM detected light-chain restriction in 11 of 14 B-cell lymphoma patients but none of the B-cell pseudolymphoma patients. The sensitivity of skin FCM for distinguishing B-cell lymphoma and B-cell pseudolymphoma was 79%, and the specificity was 100%. Eleven of 13 B-cell lymphoma patients exhibited gene rearrangement (sensitivity 85%), whereas six of seven pseudolymphoma patients were negative (specificity 86%). ISH was positive in three of 16 B-cell lymphoma cases (sensitivity 19%) but none of the B-cell pseudolymphoma cases (specificity 100%). ISH sensitivity was 29% for pcDLBCL-LT, 17% for DLBCL-NOS, and 0% for pcFCL and follicular lymphoma. Skin FCM therefore appears to be more sensitive than ISH in detecting light-chain restriction in DLBCL and follicular lymphoma, and as sensitive as IgH gene rearrangement analysis in detecting clonality. Skin FCM is thus a promising diagnostic tool for identifying monoclonal neoplastic B-cell populations.

Functional Depletion of HSP72 by siRNA and Quercetin Enhances Vorinostat-Induced Apoptosis in an HSP72-Overexpressing Cutaneous T-Cell Lymphoma Cell Line, Hut78.

Histone deacetylase inhibitors (HDACis) are one of the therapeutic options for cutaneous T-cell lymphoma (CTCL), but they have limited effects. We previously demonstrated that HSP72 overexpression is associated with chemoresistance to HDACis in lymphoma cells. The purpose of this study was to investigate whether the functional depletion of HSP72 enhances the effect of the HDACi vorinostat. First, we established a stable HSP72-knockdown CTCL cell line and confirmed the influence of HSP72 reduction on the antitumor effects of vorinostat. Next, we studied the effect of quercetin, an inhibitor of HSP72, on the antineoplastic effects of vorinostat. In five CTCL cell lines examined, HSP72 expression was highest in Hut78 cells, and HSP72 knockdown enhanced vorinostat-induced apoptosis in these cells. Low-dose quercetin reduced HSP72 expression, increased HDAC activity, and enhanced vorinostat-induced suppression of Hut78 cell proliferation. A single low dose of quercetin induced G2 arrest and only slightly increased the sub-G1 cell fraction. Quercetin also significantly enhanced vorinostat-induced apoptosis, caspase-3, caspase-8, and caspase-9 activity, and the loss of mitochondrial membrane potential. HSP72 knockdown enhanced vorinostat-induced apoptosis in an HSP72-overexpressing CTCL cell line, and thus, quercetin may be a suitable candidate for combination therapy with vorinostat in clinical settings.

Improved quality of life of patients with generalized pustular psoriasis in Japan: A cross-sectional survey.

Generalized pustular psoriasis (GPP) is a rare variant of psoriasis with severe clinical symptoms. However, the quality of life (QoL) of the patients is largely unknown. We conducted a nationwide cross-sectional survey of Japanese GPP patients using the 36-Item Short-Form Health Survey version 2 (SF-36v2) to elucidate patients' QoL and how their QoL had changed over the last decade. We analyzed QoL data of 83 patients obtained from 2016 to 2019 (present group) and compared it with that of 105 patients collected in a previous survey conducted between 2003 and 2007 (past group). Although the QoL of the present patients was still largely impaired in comparison with the standard Japanese population, substantial improvement was found in some SF-36v2 subscales including "general health", "vitality", "social functioning" and "mental health" as compared with that of the past group. Advances in treatment may contribute to this QoL improvement.

The aim of the measurement of Epstein-Barr virus DNA in hydroa vacciniforme and hypersensitivity to mosquito bites.

Epstein-Barr virus (EBV) DNA load in the blood increases in posttransplant lymphoproliferative disorders and chronic active EBV infection. In this report, we analyzed the EBV DNA load in the peripheral blood mononuclear cells (PBMCs) and plasma of patients with hydroa vacciniforme (HV) and/or hypersensitivity to mosquito bites (HMB) to understand the clinical significance of EBV DNA load. All 30 patients showed high DNA loads in the PBMCs over the cut-off level. Of 16 plasma samples, extremely high in two samples obtained from patients with hemophagocytic lymphohistiocytosis (HLH). The amount of cell-free DNA in plasma was correlated to the serum levels of lactate dehydrogenase and inversely correlated to platelet counts. These results indicate that the EBV DNA load in PBMCs can provide one of the diagnostic indicators for HV and HMB and marked elevation of cell-free EBV DNA in plasma might be related to cytolysis such as that observed in HLH.

Epstein-Barr virus NK and T cell lymphoproliferative disease: report of a 2018 international meeting.

Epstein-Barr virus (EBV) normally infects B cells, but in some persons the virus infects T or NK cells. Infection of B cells can result in infectious mononucleosis, and the virus is associated with several B cell malignancies including Hodgkin lymphoma, Burkitt lymphoma, and diffuse large B cell lymphoma. Infection of T or NK cells with EBV is associated with extranodal NK/T cell lymphoma, aggressive NK-cell leukemia, systemic EBV-associated T-cell lymphoma, and chronic active EBV disease, which in some cases can include hydroa vacciniforme-like lymphoproliferative disease and severe mosquito bite allergy. While NK and T cell lymphoproliferative disease is more common in Asia and Latin America, increasing numbers of cases are being reported from the United States and Europe. This review focuses on classification, clinical findings, pathogenesis, and recent genetic advances in NK and T cell lymphoproliferative diseases associated with EBV.

Japanese guidelines for the management of pemphigoid (including epidermolysis bullosa acquisita).

The pemphigoid group is a category of autoimmune subepidermal blistering diseases in which autoantibodies deposit linearly at the epidermal basement membrane zone (BMZ). The main subtypes of pemphigoid mediated by immunoglobulin G autoantibodies are bullous pemphigoid (BP), mucous membrane pemphigoid (MMP) and epidermolysis bullosa acquisita (EBA). To establish the first guidelines approved by the Japanese Dermatological Association for the management of pemphigoid diseases, the Committee for Guidelines for the Management of Pemphigoid Diseases (Including EBA) was founded as part of the Study Group for Rare Intractable Skin Diseases under the Ministry of Health, Labor and Welfare Research Project on Overcoming Intractable Diseases. These guidelines aim to provide current information for the management of BP, MMP and EBA in Japan. Based on evidence, the guidelines summarize the clinical and immunological manifestations, pathophysiologies, diagnostic criteria, disease severity determination criteria, treatment algorithms and treatment recommendations. Because of the rarity of these diseases, there are few clinical studies with a high degree of evidence, so several parts of these guidelines were established based on the opinions of the Committee. To further optimize these guidelines, periodic revision in line with the new evidence is necessary.

The expression of cell adhesion molecule 1 and its splicing variants in Sézary cells and cell lines from cutaneous T-cell lymphoma.

Cell adhesion molecule 1 (CADM1) is aberrantly expressed by T-cell neoplasms such as adult T-cell leukemia/lymphoma (ATLL) and mycosis fungoides (MF). We studied the expression of CADM1 and its splicing variants in Sézary syndrome (SS), MF, other cutaneous T-cell lymphoma (CTCL), and cell lines derived from T- and B-cell lymphomas. Soluble CADM1 was measured in the patients' sera. CADM1+ cells in the blood and skin lesions were examined by flow cytometry and immunostaining, respectively. Soluble CADM1 was measured by ELISA, and the splicing variants of CADM1 transcripts were determined by reverse transcriptase-polymerase chain reaction, followed by sequencing. As a result, circulating CADM1+ cells were significantly increased in seven out of 10 patients with SS, ranging from 7.9% to 74.5% of the CD3+CD4+ fractions (median 33.7%; cut-off value 6.5%). The percentages of CADM1+ cells were usually less than those of circulating Sézary cells. CADM1 was expressed, to various degrees, in six of nine T-cell lines derived from SS, MF, ATLL, and anaplastic large cell lymphoma (ALCL), but negative in B-cell lymphoma-derived cell lines. CADM1+ cells were present in the skin infiltrates of MF, SS, ATLL and ALCL. Serum levels of soluble CADM1 were not significantly elevated in SS/MF. Three major splicing variants of CADM1 expressed by neoplastic T-cells contained different combinations of the exons 7, 8, 9 and 11, including a putative oncogenic variant composed of exons 7-8-9-11. In conclusion, CADM1 is frequently expressed in Sézary cells and cell lines from CTCL.

Clinical manifestations of skin, lung and muscle diseases in dermatomyositis positive for anti-aminoacyl tRNA synthetase antibodies.

Patients with dermatomyositis positive for anti-aminoacyl tRNA synthetase (ARS) antibodies, also known as antisynthetase syndrome (ASS), frequently present with mechanic's hand and interstitial lung disease (ILD). We first screened the antibody profiles of 59 patients with dermatomyositis, and then examined the cutaneous, muscular and pulmonary manifestations characteristic for patients with ASS. The anti-ARS antibodies Jo-1, PL-7, PL-12, EJ and KS, along with antibodies to TIF1-γ, MDA5 and Mi-2, were examined. Among the 59 patients, 20, 21, 15 and three patients were classified into the ASS, non-ASS, myositis-specific antibody-negative and unknown groups, respectively. Five of 16 patients (31%) with ASS had six relatives with a history of collagen diseases, within the second degree of relationship, including two cases of dermatomyositis (vs the non-ASS group, P = 0.018). Patients with ASS more frequently presented with fever and arthralgia, and had elevated levels of C-reactive protein. Nine of the 11 finger lesions (82%) clinically diagnosed as mechanic's hands showed a psoriasiform tissue reaction. ILD was observed in 19 of 20 patients (95%) with ASS, and eight of 21 patients (38%) in the non-ASS group, in which six patients possessed anti-MDA5 antibody. Patients with ASS showed higher serum levels of muscle enzymes, and four of 12 patients (33%) had fasciitis-dominant myopathy, while only one of 11 patients (9%) in the non-ASS group had fasciitis-dominant myopathy. Patients with ASS often present with a psoriasiform tissue reaction in the hand lesions and fasciitis-dominant myopathy, and the relatives of those with ASS are at high risk for collagen diseases.

Viral DNA Loads in Various Blood Components of Patients With Epstein-Barr Virus-Positive T-Cell/Natural Killer Cell Lymphoproliferative Diseases.

To evaluate diagnostic values for Epstein-Barr virus (EBV) DNA loads in different blood components of patients with EBV-positive T-cell/natural killer cell lymphoproliferative diseases, EBV DNA loads were compared among disease categories in each blood component from 59 patients. Plasma viral loads were significantly higher in "active" disease in chronic active EBV infection. EBV DNA was not detected in the plasma from 7 patients in whom EBV DNA was detected in peripheral blood mononuclear cells and whole blood. Diagnostic cutoff values for whole blood EBV DNA loads of patients with chronic active EBV infection compared with those of infectious mononucleosis was 104.2 (15 800) IU/mL.

Long-term efficacy and safety of bexarotene for Japanese patients with cutaneous T-cell lymphoma: The results of a phase 2 study (B-1201).

The present study (B-1201 clinical trial) was conducted as a multicenter, open-label, single-arm phase II study to evaluate the long-term safety, tolerability and efficacy of bexarotene. This study enrolled 10 Japanese adults aged more than 20 years with cutaneous T-cell lymphoma (CTCL) who completed the 24-week study period of the B-1101 trial. The objective response rate (ORR) was 53.8% (95% confidence interval, 25.1-80.8). In the early stage (IB), the ORR was 60% (3/5 cases). In the advanced stage (IIB and IIIA), the ORR was 57.1% (4/7 cases). The median time to response was 58 days (range, 27-168). The median treatment duration was 380 days (range, 33-1674). The median duration of response (DOR) could not be reached during the study period. The longest DOR reached 1618 days at the end of the B-1201 trial. Nine patients (56.3%) in the full analysis set (FAS) population experienced dose reduction of bexarotene. Common drug-related adverse events in the FAS population included hypothyroidism (93.8%), hypertriglyceridemia (81.3%), hypercholesterolemia (81.3%), leukopenia (68.8%) and neutropenia (56.3%). Dose-limiting toxicity (DLT) was present in five (38.5%) of the 13 patients in the 300 mg/m2 cohort. Of the five patients, four developed grade 3 neutropenia and one developed grade 4 hypertriglyceridemia. All DLT cases recovered after the discontinuation of bexarotene. None of the five patients discontinued this trial because of DLT. The B-1201 trial shows the long-term safety of oral bexarotene for Japanese patients with CTCL, despite frequent dose reduction.

Hydroa vacciniforme: a distinctive form of Epstein-Barr virus-associated T-cell lymphoproliferative disorders.

Hydroa vacciniforme (HV) is a cutaneous subset of Epstein-Barr virus (EBV)-associated T/NK lymphoproliferative disorders (LPDs). Our previous case series study clearly showed a clinical spectrum of EBV-associated T/NK LPDs including HV, hypersensitivity to mosquito bites (HMB), chronic active EBV infection (CAEBV), and hemophagocytic lymphohistiocytosis (HLH). Patients with HV are divided into two groups: a benign subtype designated "classic HV" (cHV) and more serious systemic HV (sHV), also called "HV-like LPD" in the 2017 World Health Organization (WHO) classification. Patients with cHV usually have an increased number of EBV-infected γδT cells and patients with sHV without HMB are further classified into two groups: γδT-cell- and αßT-cell-dominant types. Patients with HMB, with or without HV-like eruptions, have an increased number of EBV-infected NK cells in the blood. Patients with cHV and γδT-cell-dominant sHV show a favourable prognosis, but the other subtypes such as αßT-cell-dominant sHV and HMB have a poor prognosis with mortality rates of 11.5 and 3.51 per 100 person-years, respectively. In addition to the clinical subtypes and the dominant lymphocyte subsets, the poor prognostic indicators include onset age over nine years and expression of the reactivation marker, BZLF1 mRNA. No prognostic correlation has been reported for anti-EBV antibody titres or EBV DNA load. The clinical subtypes and their prognostic factors should be considered for therapeutic interventions.

Publisher Correction: Defective Epstein-Barr virus in chronic active infection and haematological malignancy.

In the version of this Letter originally published, in the sentence beginning "The major driver role of DDX3X mutations...", the citation "Fig. 2a-f" should have been "Fig. 2". In addition, in the sentence beginning "Another finding of interest was the presence of identical driver mutations...", the citation "Fig. 3a,b and Fig. 4" should have been "Fig. 3". This has now been amended in all versions of the Letter.