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

<ORIGINAL ARTICLE>Histologic investigation of tissue surrounding bone in a HA-coated implant supported super structure with and without stress-absorbing elements

The effectiveness of the implant-supported overdentures has been attracted attention for edentulous patients, and a number of studies have been reported. Implant-supported overdentures refer to implant-retained tissue-borne overdentures and it is different from the implant-supported fixed partial dentures recommended by Branemark. In implant-supported overdentures, the functional load may concentrate on implant where there is rigid connection. Loaded implants may cause a resorption of surrounding bone, leading to malfunction, loosing, and the ultimate failure of the implant. The present study reports a stress-absorbing element using a resilient compound designed as the super structure of a two-piece titanium core with hydroxyapatite coated cylinder implants, to avoid stress concentrations, and a histological comparison of the surrounding bone tissue with rigid elements. No notable histological differences were observed in the trabecular patterns by contact microradiography and light microscopy

TNF-α and IL-17A induce the expression of lympho-epithelial Kazal-type inhibitor in epidermal keratinocytes

BACKGROUND: Serine proteases have important roles in skin barrier function and desquamation, and the aberrant expression or the dysfunction of serine proteases is associated with the pathogenesis of skin diseases. Serine protease activities are tightly regulated by serine proteases such as kallikrein-related peptidases (KLKs) and serine protease inhibitors such as lympho-epithelial Kazal-type related inhibitor (LEKTI). For a better understating of diseases' pathogenesis, the regulation mechanism of serine proteases and the inhibitors' expression in epidermal keratinocytes must be clarified. OBJECTIVES: To investigate the effects of the cytokines on the expression of LEKTI in epidermal keratinocytes. METHODS: Normal human epidermal keratinocytes (NHEKs) were stimulated with panels of inflammatory cytokines. The expression of serine protease inhibitors was analyzed using quantitative real-time PCR and ELISA. LEKTI expression in normal human skin and lesions from psoriasis or atopic dermatitis (AD) were analyzed by immunohistochemically and tape-stripping. Trypsin- and chymotrypsin-like serine protease activities in culture supernatants were measured by using specific substrates. RESULTS: TNF-α and IL-17A significantly induced the expression of LEKTI in NHEKs. The immunohistochemical and tape-stripping analysis revealed that psoriatic skin lesions had higher LEKTI expression compared to normal skin and AD lesions. Trypsin- and chymotrypsin-like protease activities in the culture media were upregulated 3-5 days later but attenuated 6-7 days later period by these cytokines. CONCLUSIONS: In epidermal keratinocytes, the Th1&Th17 cytokines TNF-α and IL-17A induce the expression of serine protease inhibitor LEKTI, and it might occur to suppress the increase in the serine protease activities under inflammation

Multifaceted Analyses of Epidermal Serine Protease Activity in Patients with Atopic Dermatitis

The serine proteases kallikrein-related peptidase (KLK) 5 and KLK7 cleave cell adhesion molecules in the epidermis. Aberrant epidermal serine protease activity is thought to play an important role in the pathogenesis of atopic dermatitis (AD). We collected the stratum corneum (SC) from healthy individuals (n = 46) and AD patients (n = 63) by tape stripping and then measuring the trypsin- and chymotrypsin-like serine protease activity. We also analyzed the p.D386N and p.E420K of SPINK5 variants and loss-of-function mutations of FLG in the AD patients. The serine protease activity in the SC was increased not only in AD lesions but also in non-lesions of AD patients. We found, generally, that there was a positive correlation between the serine protease activity in the SC and the total serum immunoglobulin E (IgE) levels, serum thymus and activation-regulated chemokine (TARC) levels, and peripheral blood eosinophil counts. Moreover, the p.D386N or p.E420K in SPINK5 and FLG mutations were not significantly associated with the SC's serine protease activity. Epidermal serine protease activity was increased even in non-lesions of AD patients. Such activity was found to correlate with a number of biomarkers of AD. Further investigations of serine proteases might provide new treatments and prophylaxis for AD

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection

DOCK2 is involved in the host genetics and biology of severe COVID-19

「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target