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Biology subjects

Mi, R.

Publications and source records attributed to Mi, R..

3 recordsLinked to original sources

Stray cats and dogs carrying zoonotic Enterocytozoon bieneusi genotype D in China: a public health concern

Enterocytozoon bieneusi is reported to be a common microsporidian of humans and animals in various countries. However, scarce information on E. bieneusi has been recorded in cats (Felis catus) and dogs (Canis familiaris) in China. As such, we undertook molecular epidemiological investigation of E. bieneusi in cats and dogs in Shanghai, China. A total of 359 genomic DNAs were extracted from individual faecal samples from cats (n = 59) and dogs (n = 300), and then tested using a nested PCR-based sequencing approach employing internal transcribed spacer (ITS) of nuclear ribosomal DNA as the genetic marker. Enterocytozoon bieneusi was detected in 34 of all 359 (9.5%) faecal samples from cats (32.2%; 19/59) and dogs (5.0%; 15/300), including 24 stray cats and dogs (22.6%; 24/106), as well as ten household/raised cats and dogs (4.0%; 10/253). Correlation analyses revealed that E. bieneusi positive rates were significantly associated with stray cats and dogs (P < 0.05). The analysis of ITS sequence data revealed the presentation of five known genotypes CD7, CHN-HD2, D, PtEb IX and Type IV and two novel genotypes D-like1 and PtEb IX-like1. Zoonotic genotype D was the predominant type with percentage of 61.8 (21/34). Phylogenetic analysis of ITS sequence data sets showed that genotypes D, D-like1 and Type IV clustered within Group 1, showing zoonotic potential. The others were assigned into Group 10 with host specificity. These findings suggested that cats and dogs in Shanghai harbor zoonotic genotype D of E. bieneusi and may have a significant risk for zoonotic transmission. Further insight into the epidemiology of E. bieneusi in animals, water and the environment from other areas in China will be important to have an informed position on the public health significance of microsporidiosis caused by this microbe.

genetics↗

Single-cell RNA-seq analysis reveals aberrant CSF1 expression in disease-causing synovial fibroblasts of pigmented villonodular synovitis

ObjectivesAlthough the role of the CSF1/CSF1R axis in pigmented villonodular synovitis (PVNS) has been confirmed, the cells that express CSF1 and CSF1R and the underlying mechanism remain unclear. Single-cell RNA sequencing (scRNA-seq) of PVNS obtained through biopsies depicted the cellular diversity of PVNS, revealed specific CSF1/CSF1R-expressing cells and further identified novel gene expression that is associated with the development of PVNS. MethodsscRNA-seq was performed on tissues obtained from the 6 biopsies of 3 patients with PVNS. Flow cytometry, immunofluorescence and western blot validated the transcriptional results, while co-culture systems revealed the cross talk between fibroblasts and macrophages. Results8 subsets of fibroblasts and 5 subsets of macrophages were identified from the synovium of patients with PVNS and were found to be related to distinct signaling pathways. The cellular components of localized and diffuse PVNS are overall similar. Moreover, the synovium and nodule of PVNS share similar composition. The specific cells expressing CSF1/CSF1R were also identified. Other than that, unique CXCL12+CSF1+ fibroblasts were revealed to attract macrophages as disease-causing synovial fibroblasts, leading to the formation of masses in PVNS. ConclusionsPVNS consists of macrophages, fibroblasts, T cells, endothelial cells and mast cells. Among them, the CSF1-expressing fibroblasts appeared to be tumor-like cells that attract macrophages, subsequently forming tumor-like mass in PVNS. This paves the path for novel treatments of PVNS by targeting CXCL12+CSF1+ fibroblasts and the CXCL12-CXCR4 axis.

molecular biology↗

ATF6 aggravates angiogenesis-osteogenesis coupling during ankylosing spondylitis by mediating FGF2 expression in chondrocytes

Although angiogenesis-osteogenesis coupling is important in ankylosing spondylitis (AS), therapeutic agents targeting the vasculature remain elusive. Here, we identified activating transcription factor 6 (ATF6) as an important regulator of angiogenesis in AS patients. Firstly, we found that ATF6 and fibroblast growth factor 2 (FGF2) levels were higher in SKG mice and AS patient cartilage. The pro-angiogenic ability of human chondrocytes was enhanced through activated ATF6-FGF2 axis following long-term stimulation with inflammatory factors, e.g. TNF-, IFN-{gamma} or IL-17. Mechanistically, ATF6 interacted with the FGF2 promotor and promoted its transcription. Treatment with the ATF6 inhibitor Ceapin-A7 inhibited angiogenesis in vitro and angiogenesis-osteogenesis coupling in vivo. ATF6 may aggravate angiogenesis-osteogenesis coupling during AS by mediating FGF2 transcription in chondrocytes, implying that ATF6 represents a promising therapeutic target for AS.

molecular biology↗