Inhibition of CD44 intracellular domain production suppresses bovine articular chondrocyte de-differentiation induced by excessive mechanical stress loading

CD44 fragmentation is enhanced in chondrocytes of osteoarthritis (OA) patients. We hypothesized that mechanical stress-induced enhancement of CD44-intracellular domain (CD44-ICD) production plays an important role in the de-differentiation of chondrocytes and OA. This study aimed to assess the relationship between CD44-ICD and chondrocyte gene expression. Monolayer cultured primary bovine articular chondrocytes (BACs) were subjected to cyclic tensile strain (CTS) loading. ADAM10 inhibitor (GI254023X) and γ-secretase inhibitor (DAPT) were used to inhibit CD44 cleavage. In overexpression experiments, BACs were electroporated with a plasmid encoding CD44-ICD. CTS loading increased the expression of ADAM10 and subsequent CD44 cleavage, while decreasing the expression of SOX9, aggrecan, and type 2 collagen (COL2). Overexpression of CD44-ICD also resulted in decreased expression of these chondrocyte genes. Both GI254023X and DAPT reduced the production of CD44-ICD upon CTS loading, and significantly rescued the reduction of SOX9 expression by CTS loading. Chemical inhibition of CD44-ICD production also rescued aggrecan and COL2 expression following CTS loading. Our findings suggest that CD44-ICD is closely associated with the de-differentiation of chondrocytes. Excessive mechanical stress loading promoted the de-differentiation of BACs by enhancing CD44 cleavage and CD44-ICD production. Suppression of CD44 cleavage has potential as a novel treatment strategy for OA

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

Elevation in Serum Concentration of Bone-Specific Alkaline Phosphatase without Elevation in Serum Creatinine Concentration Secondary to Adefovir Dipivoxil Therapy in Chronic Hepatitis B Virus Infection

Of 168 patients with chronic hepatitis B virus (HBV) infection-related liver disease, 20 patients who had received 100 mg of lamivudine plus 10 mg/day of adefovir dipivoxil (ADV) (ADV group) and 124 patients who had received 0.5 mg/day of entecavir or 100 mg/day of lamivudine (non-ADV group) for >1 year were enrolled. For comparative analyses, 19 well-matched pairs were obtained from the groups by propensity scores. At the time of enrollment, serum creatinine and phosphate concentrations were similar between the ADV and non-ADV groups; however, urinary phosphate () and serum bone-specific alkaline phosphatase (BAP) () concentrations were significantly higher in the ADV group than in the non-ADV group. Serum BAP was significantly higher at the time of enrollment than before ADV administration in the ADV group (), although there was no significant change in serum BAP concentration in the non-ADV group. There was a significant positive correlation between the period of ADV therapy and ΔBAP (, ). Serum BAP concentration increased before increase in serum creatinine concentration and was useful for early detection of adverse events and for developing adequate measures for continuing ADV for chronic HBV infection-related liver disease

A Fatal Case of Relapsing Pneumonia Caused by in a Patient with Rheumatoid Arthritis After Two Injections of Adalimumab

We present a rare fatal case of relapsing pneumonia caused by Legionella pneumophila in a patient with rheumatoid arthritis after only two injections of adalimumab. A 78-year-old Japanese woman with a 14-year history of rheumatoid arthritis was prescribed adalimumab because her disease activity remained high. However, 8 days after her second injection of adalimumab, she was admitted to our hospital and diagnosed with pneumonia caused by L. pneumophila . Following intravenous antibiotic therapy, she recovered completely from pneumonia and was discharged on day 10, but pneumonia relapsed, resulting in death 79 days after the first episode of pneumonia. L. pneumophila can lead to recurrence of pneumonia that can ultimately prove fatal, similar to the present case. A review of the pertinent literature is also presented

Usefulness of sennoside as an agent for mechanical bowel preparation prior to elective colon cancer surgery

We retrospectively evaluated the usefulness of sennoside as an agent for mechanical bowel preparation prior to elective colon cancer surgery. A total of 86 patients were given 12 mg of sennoside on the evening prior to resective surgery for colon cancer, followed by intravenous antimicrobial prophylaxis used on the day of surgery or until postoperative day 2. The incidence of surgical site infection in the study group was 4.7%, which was comparable to that in the historical control patients (3.5%, p > 0.99), who had received polyethylene glycol for mechanical bowel preparation prior to colon surgery. On multivariate logistic regression analysis, only body mass index (p = 0.04) was an independent significant factor affecting the surgical site infection. The intraoperative spillage was not influenced by the presence of stenosis, although the amount of fecal matter was higher in the upstream colon segment (p < 0.01) and downstream segment (p = 0.07) in patients with a stenotic lesion occupying more than two-thirds of the lumen (n = 29) than in those without such severe stenosis (n = 57). Sennoside seems to be an acceptable agent for mechanical bowel preparation even in patients with stenosis

Usefulness of sennoside as an agent for mechanical bowel preparation prior to elective colon cancer surgery

Objective: We retrospectively evaluated the usefulness of sennoside as an agent for mechanical bowel preparation prior to elective colon cancer surgery. Methods: A total of 86 patients were given 12 mg of sennoside on the evening prior to resective surgery for colon cancer, followed by intravenous antimicrobial prophylaxis used on the day of surgery or until postoperative day 2. Results: The incidence of surgical site infection in the study group was 4.7%, which was comparable to that in the historical control patients (3.5%, p>0.99), who had received polyethylene glycol for mechanical bowel preparation prior to colon surgery. On multivariate logistic regression analysis, only body mass index (p=0.04) was an independent significant factor affecting the surgical site infection. The intraoperative spillage was not influenced by the presence of stenosis, although the amount of fecal matter was higher in the upstream colon segment (p<0.01) and downstream segment (p=0.07) in patients with a stenotic lesion occupying more than two-thirds of the lumen (n=29) than in those without such severe stenosis (n=57). Conclusion: Sennoside seems to be an acceptable agent for mechanical bowel preparation even in patients with stenosis