PU.1 promotes development of rheumatoid arthritis via repressing FLT3 in macrophages and fibroblast-like synoviocytes.

OBJECTIVES: To uncover the function and underlying mechanism of an essential transcriptional factor, PU.1, in the development of rheumatoid arthritis (RA). METHODS: The expression and localisation of PU.1 and its potential target, FMS-like tyrosine kinase 3 (FLT3), in the synovium of patients with RA were determined by western blot and immunohistochemical (IHC) staining. UREΔ (with PU.1 knockdown) and FLT3-ITD (with FLT3 activation) mice were used to establish collagen antibody-induced arthritis (CAIA). For the in vitro study, the effects of PU.1 and FLT3 on primary macrophages and fibroblast-like synoviocytes (FLS) were investigated using siRNAs. Mechanistically, luciferase reporter assays, western blotting, FACS and IHC were conducted to show the direct regulation of PU.1 on the transcription of FLT3 in macrophages and FLS. Finally, a small molecular inhibitor of PU.1, DB2313, was used to further illustrate the therapeutic effects of DB2313 on arthritis using two in vivo models, CAIA and collagen-induced arthritis (CIA). RESULTS: The expression of PU.1 was induced in the synovium of patients with RA when compared with that in osteoarthritis patients and normal controls. FLT3 and p-FLT3 showed opposite expression patterns compared with PU.1 in RA. The CAIA model showed that PU.1 was an activator, whereas FLT3 was a repressor, of the development of arthritis in vivo. Moreover, results from in vitro assays were consistent with the in vivo results: PU.1 promoted hyperactivation and inflammatory status of macrophages and FLS, whereas FLT3 had the opposite effects. In addition, PU.1 inhibited the transcription of FLT3 by directly binding to its promoter region. The PU.1 inhibitor DB2313 clearly alleviated the effects on arthritis development in the CAIA and CIA models. CONCLUSIONS: These results support the role of PU.1 in RA and may have therapeutic implications by directly repressing FLT3. Therefore, targeting PU.1 might be a potential therapeutic approach for RA.

The application of HER2 and CD47 CAR-macrophage in ovarian cancer.

BACKGROUND: The chimeric antigen receptor (CAR)-T therapy has a limited therapeutic effect on solid tumors owing to the limited CAR-T cell infiltration into solid tumors and the inactivation of CAR-T cells by the immunosuppressive tumor microenvironment. Macrophage is an important component of the innate and adaptive immunity, and its unique phagocytic function has been explored to construct CAR macrophages (CAR-Ms) against solid tumors. This study aimed to investigate the therapeutic application of CAR-Ms in ovarian cancer. METHODS: In this study, we constructed novel CAR structures, which consisted of humanized anti-HER2 or CD47 scFv, CD8 hinge region and transmembrane domains, as well as the 4-1BB and CD3ζ intracellular domains. We examined the phagocytosis of HER2 CAR-M and CD47 CAR-M on ovarian cancer cells and the promotion of adaptive immunity. Two syngeneic tumor models were used to estimate the in vivo antitumor activity of HER2 CAR-M and CD47 CAR-M. RESULTS: We constructed CAR-Ms targeting HER2 and CD47 and verified their phagocytic ability to ovarian cancer cells in vivo and in vitro. The constructed CAR-Ms showed antigen-specific phagocytosis of ovarian cancer cells in vitro and could activate CD8+ cytotoxic T lymphocyte (CTL) to secrete various anti-tumor factors. For the in vivo model, mice with human-like immune systems were used. We found that CAR-Ms enhanced CD8+ T cell activation, affected tumor-associated macrophage (TAM) phenotype, and led to tumor regression. CONCLUSIONS: We demonstrated the inhibition effect of our constructed novel HER2 CAR-M and CD47 CAR-M on target antigen-positive ovarian cancer in vitro and in vivo, and preliminarily verified that this inhibitory effect is due to phagocytosis, promotion of adaptive immunity and effect on tumor microenvironment.

An assessment of the reproductive toxicity of GONPs exposure to Bombyx mori.

This study aimed to explore the toxicity of environmental residues of graphene oxide nanoparticles (GONPs) to reproduction of Lepidopteron insects using both ovary cell line (BmN) and individual female Bombyx mori as the research subjects. The results showed that GONPs dose dependently affect BmN cells. At higher concentrations (>25 mg/L), GONPs led to oxidative stress, ROS accumulation and DNA damage in BmN cells and significantly reduced their survival rate (p ≤ 0.05). Moreover, feeding female B. mori larvae with mulberry leaves treated with 25 mg/L GONPs significantly decreased their gonadosomatic index (GSI) by 40.84%, and increased oxidation levels and antioxidant enzyme activity in silkworm ovary tissues. Pathological analysis found that exposure to GONPs decreased the numbers of both oogonia and oocytes in ovarian tissues, increased the formation of peroxisome and vacuoles in follicle cells, reduced the transcription of genes (Vg, Ovo, Sxl-s, Sxl-l, and Otu) related to ovarian development in B. mori by 0.61, 0.65, 0.75, 0.72, and 0.42-fold, respectively, and lowered the amount of spawning by 52.25%. Overall, these results revealed that GONPs exposure is toxic to the reproduction of B. mori. The underlying mechanism is that oxidative stress due to GONPs causes oxidative damage to DNA, damages ovarian tissues, as well as hinders B. mori development and spawning. Thus, this study provides important experimental data for safety evaluation of reproductive toxicity due to GONPs exposure.

Complete mitochondrial genome of Spilosoma lubricipedum (Noctuoidea: Erebidae) and implications for phylogeny of noctuid insects.

Mitochondrial genomes (mitogenomes) have been widely used for studies on phylogenetic relationships and molecular evolutionary biology. Here, the complete mitogenome sequence of Spilosoma lubricipedum (Noctuoidea: Erebidae: Arctiinae) was determined (total length 15,375 bp) and phylogenetic analyses S. lubricipedum were inferred from available noctuid sequence data. The mitogenome of S. lubricipedum was found to be highly A + T-biased (81.39%) and exhibited negative AT- and GC-skews. All 13 protein-coding genes (PCGs) were initiated by ATN codons, except for cox1 with CGA. All tRNAs exhibited typical clover-leaf secondary structures, except for trnS1. The gene order of the S. lubricipedum mitogenome was trnM-trnI-trnQ-nad2. The A + T-rich region of S. lubricipedum contained several conservative features common to noctuid insects. Phylogenetic analysis within Noctuoidea was carried out based on mitochondrial data. Results showed that S. lubricipedum belonged to Erebidae and the Noctuoidea insects could be divided into five well-supported families (Notodontidae + (Erebidae + (Nolidae + (Euteliidae + Noctuidae)))).

The emerging role of fibroblast-like synoviocytes-mediated synovitis in osteoarthritis: An update.

Osteoarthritis (OA), the most ubiquitous degenerative disease affecting the entire joint, is characterized by cartilage degradation and synovial inflammation. Although the pathogenesis of OA remains poorly understood, synovial inflammation is known to play an important role in OA development. However, studies on OA pathophysiology have focused more on cartilage degeneration and osteophytes, rather than on the inflamed and thickened synovium. Fibroblast-like synoviocytes (FLS) produce a series of pro-inflammatory regulators, such as inflammatory cytokines, nitric oxide (NO) and prostaglandin E2 (PGE2 ). These regulators are positively associated with the clinical symptoms of OA, such as inflammatory pain, joint swelling and disease development. A better understanding of the inflammatory immune response in OA-FLS could provide a novel approach to comprehensive treatment strategies for OA. Here, we have summarized recently published literatures referring to epigenetic modifications, activated signalling pathways and inflammation-associated factors that are involved in OA-FLS-mediated inflammation. In addition, the current related clinical trials and future perspectives were also summarized.

The effects of long non-coding ribonucleic acids on various cellular components in rheumatoid arthritis.

RA is a chronic, autoimmune-mediated inflammatory pathology. Long non-coding RNAs (lncRNAs) are a novel group of non-coding RNAs with a length of >200 nucleotides. There are reports emerging that suggest that lncRNAs participate in establishing and sustaining autoimmune diseases, including RA. In this review article, we highlight the functions of lncRNAs in different cell types in RA. Our review indicates that lncRNAs affect various cellular components and are novel candidates that could constitute promising targets for the diagnosis and treatment of RA.

Identification of the nucleotide exchange factor BmGrpE and its role under high-temperature stress in silkworm, Bombyx mori.

The high-temperature stress gene GrpE plays an important role in coping with high-temperature stress. The mutation of key sites of this gene can improve the high-temperature resistance of organisms. In the present study, using complementary DNAs from the silkworm fat body as the template, the open reading frame sequence of the GrpE gene (BmGrpE) was amplified and was found to be 644 bp in length and encode a protein with a predicted molecular weight of 24.1 kDa. The presence of a binding site for the heat shock transcription factor (Hsf1) at -1440 bp upstream of its coding region indicates that BmGrpE may respond to high-temperature stress. BmGrpE was constitutively expressed throughout developmental stages, with the highest level observed in the 5th instar larvae stage. Moreover, in 5th instar larvae (the 3th day), BmGrpE was expressed in all tissues examined, with the highest levels in the fat body, silk gland, and midgut. Interestingly, under high-temperature stress, TiO2 nanoparticle treatment increased the messenger RNA levels of BmGrpE in the fat body and silk gland. After treatment with dsRNA of BmGrpE, the cell viability of BmN cells was significantly decreased under 34°C and H2 O2 stress (p < .05). Mutation of BmGrpE (H163L) enhanced the resistance of BmN cells under high-temperature stress. These results provide new clues for the study of molecular mechanisms of insect resistance to high temperatures.

Synovial Macrophages in Rheumatoid Arthritis: The Past, Present, and Future.

The ontogeny of macrophages in most organs has already been established. Owing to the limited number and inaccessibility of synovial macrophages (SMs), the origin of SMs has not been fully elucidated. Previous studies suggested that SMs have two major origins, namely, tissue-resident and monocyte-derived SMs. However, no systematic analysis to identify SM ontology in either physiological or pathological conditions has been available to date. In this review, we summarize relevant studies on the two main origins of SMs in rheumatoid arthritis (RA) and forecast the future research directions for this field. Furthermore, we discuss the current state of RA therapy that is based on targeting different SM subsets.

Effects of phoxim exposure on gut microbial composition in the silkworm, Bombyx mori.

Organophosphate pesticides are widely applied worldwide for agricultural purposes, and their exposures often result in adverse effects on Bombyx mori. The insect gut is a complicated ecosystem inhabited by a large number of microbes that play important roles in insect physiology and behavior. Recent studies have reported that alteration of their microbiota due to stressful conditions or environmental changes has been linked to a compromised health status and a susceptibility to diseases. In the present study, we aimed to assess the effects of phoxim exposure on intestinal microbes in silkworms. The results showed that phoxim exposure increased the bacterial community evenness and altered the structure of gut microbiota in silkworm larvae. The abundances of several genera, such as Methylobacterium and Aurantimonadaceae, in phoxim-treated larval guts were significantly reduced compared with the H2O-treated group, whereas the abundances of non-dominant bacteria, such as Staphylococcus, were significantly increased. Moreover, phoxim inhibited the expressions of antimicrobial peptides (AMPs) at the mRNA level and enhanced the pathogenesis of Enterobacter cloacae (E. cloacae) against silkworm larvae, suggesting that the immune system was inhibited after phoxim exposure. Therefore, the gut microbial community shifts were apparent after phoxim exposure. The compositional and structural changes of intestinal microbes caused by phoxim exposure might affect the normal function of the intestinal tract of silkworm. These results highlighted the importance of the gut bacterial community when investigating the mechanisms of midgut injury after pesticide exposure in Bombyx mori.

Induction of ER stress, antioxidant and detoxification response by sublethal doses of chlorantraniliprole in the silk gland of silkworm, Bombyx mori.

Sublethal doses of chlorantraniliprole (CAP) disrupt spinning disorder in the silkworm Bombyx mori (B. mori) and cause reduced cocoon production. In the present study, we investigated the effects of trace amounts of CAP on morphology and gene expression of the B. mori silk gland, found the posterior silk gland cells were possessed of disintegrated Endoplasmic reticulum (ER), unevenly distributed chromatin after exposure to CAP (0.01 mg/L). Gene expression analysis revealed that IRE1 and ATF6 ER stress-signaling pathways were inhibited, the PERK/CncC pathway was activated. Digital gene expression (DGE) analysis showed that detoxification-related genes, antioxidant genes and genes involved in ER protein processing pathway were expressed differentially in CAP-treated silkworm larvae. Notably, the transcript levels of the detoxification-related genes (CYP4M5, CYP6AB4, GSTD3 and GSTS1) and the antioxidant genes (CAT, TPX and SOD) were significantly increased, and the expression of ER protein processing-related genes (Sec61ß, Sec61γ, Sec23α and ERGIC-53) was significantly decreased after CAP exposure. The results showed that sublethal doses of CAP exposure caused ER stress, oxidative damage to the silk gland and the perturbation of protein processing in ER, thereby probably leading to abnormal growth of the silk gland and triggering the spinning failure in silkworm.

Effects of phoxim pesticide on the immune system of silkworm midgut.

Silkworm (Bombyx mori) is an important economic insect. Bombyx mori, which is exposed to sublethal doses of pesticides, has a low or no mortality rate, while it is susceptible to infections triggered by foreign pathogens. The immune regulatory mechanism of silkworms caused by trace pesticides still remains unclear. The midgut is the major organ of silkworm for digestion and nutrient absorption, and it plays a critical defensive role against pathogens. In the present study, the silkworm was susceptible to Enterobacter cloacae sp. (E. cloacae) after exposure to sublethal dose of phoxim. The body weight and survival rate of the phoxim-E. cloacae co-treatment group were significantly decreased after 120 h of treatment compared with the phoxim treatment group. The immune responses and expressions of immune-related genes were dysregulated in the midgut of silkworm following exposure to phoxim. Digital gene expression (DGE) analysis revealed that 44 immune response-related and immune defense-related genes were differentially expressed. qRT-PCR results indicated that the transcriptional levels of antimicrobial peptide genes Bmdefensin1, BmcecA, Bmglv1, Bmglv2, Bmmoricin and BmmoricinB3 were down-regulated by 0.77-, 0.37-, 0.05-, 0.19-, 0.34- and 0.54-fold, respectively. The transcriptional levels of Toll signaling pathway genes Bmcactus, Bmspatzle and Bmrel were down-regulated by 0.4-, 0.37- and 0.96-fold, respectively. Peritrophic membrane (PM) protein-related genes BmCBP-02, BmPM-41, BmPM-43 and BmCDA7 were down-regulated by 0.18-, 0.02-, 0.66- and 0.16-fold, respectively. The expressions of Toll signaling pathway genes were down-regulated at 48 h and 72 h. Immune deficiency (IMD) and Janus kinase and signal transducer and activator of transcription (JAK/STAT) signaling pathway genes were dysregulated after phoxim exposure. These results indicated that phoxim might cause damage to the PM and reduce the immune response of the silkworm, leading to susceptibility of silkworm to disease and damage from foreign pathogens.

The mechanism of damage to the posterior silk gland by trace amounts of acetamiprid in the silkworm, Bombyx mori.

Acetamiprid is a new neonicotinoid insecticide widely used in the prevention and control of pests in agriculture. However, its residues in the environment affect the cocooning of the silkworm, Bombyx mori (B. mori), a non-target insect. To investigate the mechanism of damage, B. mori larvae were fed with trace amounts of acetamiprid (0.15 mg/L). At 96 h after exposure, the larvae showed signs of poisoning and decreased body weight, resulting in reduced survival and ratio of cocoon shell. At 48 h and 96 h after exposure, the residues in the posterior silk gland (PSG), which is responsible for synthesizing silk fibroin, were 0.72 µg/mg and 1.21 µg/mg, respectively, as measured by high performance liquid chromatography, indicating that acetamiprid can accumulate in the PSG. Moreover, pathological sections and transmission electron microscopy also demonstrate the damage of the PSG by acetamiprid. Digital gene expression (DGE) and KEGG pathway enrichment analysis revealed that genes related to metabolism, stress responses and inflammation were significantly up-regulated after exposure. Quantitative RT-PCR analysis showed that the transcript levels of FMBP-1 and FTZ-F1 (transcription factors for synthesizing silk protein) were up-regulated by 2.55-and 1.56-fold, respectively, and the transcript levels of fibroin heavy chain (Fib-H), fibroin light chain (Fib-L), P25, Bmsage and Bmdimm were down-regulated by 0.75-, 0.76-, 0.65-, 0.44- and 0.40-fold, respectively. The results indicate that accumulated acetamiprid causes damage to the PSG and leads to reduced expression of genes responsible for synthesizing silk fibroin. Our data provide reference for evaluating the safety of acetamiprid residues in the environment for non-target insects.

Effects of sublethal phoxim exposure and lower food intake on nutrient metabolism in the midguts of Bombyx mori.

Silkworm (Bombyx mori) is an economically important insect. However, the survival of silkworms has been significantly affected by the assault of chemical pesticides on mulberry trees through aerial application and water currents. Phoxim is a broad-spectrum organophosphorus insecticide widely used in China. Currently, very little is known about the non-neuronal effects of sublethal exposure to phoxim. The purpose of this study was to investigate the non-neuronal effects of sublethal phoxim exposure in the silkworm midgut, with a focus on nutrient metabolism. After phoxim treatment, lipase activity in the silkworm was shown to be up-regulated at 24 h before a decreasing trend was seen. Meanwhile, α-amylase activity showed the opposite trend. The expression levels of mitochondrial respiratory chain-related genes were all up-regulated at 24 h before falling continuously. To ensure that the effects of phoxim on nutrient metabolism were not simply a consequence of a decrease in mulberry consumption, the silkworms were treated with a reduced-food diet before the digestive enzyme activities and the transcription levels of mitochondrial respiratory chain-related genes were analyzed. Our results showed that the patterns in the reduced-diet and phoxim-exposed silkworm were markedly different, suggesting the alterations in the phoxim-exposed silkworm cannot readily be explained by nutrient deprivation.

The CncC/keap1 pathway is activated in high temperature-induced metamorphosis and mediates the expression of Cyp450 genes in silkworm, Bombyx mori.

Global warming is known to affect the growth, development and reproduction of insects. In this study, the larvae developmental process and endogenous hormone levels under high temperature (36 °C) stress were investigated in the lepidopteran model insect Bombyx mori (B. mori). After high temperature treatment, the duration of 5th instar larvae was shortened by 28 ±â€¯2 h, the content of 20-hydroxyecdysone(20E) in hemolymph was significantly increased, and the transcription levels of the 20E response genes E93, Br-C, USP and E75 were up-regulated by 1.35-, 1.25-, 1.28-, and 1.27-fold, respectively. High temperature treatment also elevated the phosphorylation level of Akt and activated the downstream BmCncC/keap1 pathway, and the transcription levels of the 20E synthesis-related genes cyp302a1, cyp306a1, cyp314a1 and cyp315a1 were up-regulated by 1.12-, 1.51-, 2.17- and 1.23-fold, respectively. The transcription levels of cyp302a1 and cyp306a1 were significantly decreased in BmN cells after treatment with the double stranded RNA of BmCncC (dsBmCncC), whereas their transcription levels were significantly increased (2.15- and 1.31-fold, respectively) after treatment with the CncC agonist Curcumin. These results demonstrated that high temperature treatment promoted the metamorphosis and the BmCncC/keap1 pathway played a role in the metamorphosis of B. mori. Our results provided clues for understanding the CncC/keap1 pathway-mediated regulation of metamorphosis of Lepidopteran insects.

Effects of chlorantraniliprole exposure on detoxification enzyme activities and detoxification-related gene expression in the fat body of the silkworm, Bombyx mori.

Chlorantraniliprole (CAP) can induce excessive calcium release from muscle of insects, causing muscle paralysis until death, and its residues in farmland can cause poisoning in Bombyx mori (B. mori), resulting in the failure of cocooning. No reports have investigated the effects of CAP exposure on detoxification enzyme activities and detoxification-related gene expression in B. mori. In the present study, we treated mulberry leaves with CAP by the leaf-dipping method, and then B. mori larvae were continuously fed with the polluted mulberry leaves. Moreover, the detoxification enzyme activities and the expressions of detoxification-related genes in the fat body of B. mori were examined. The results showed that at 24 h after CAP exposure, the activities of P450 and GST enzymes were all significantly increased, with P450 enzymes responding fastest. CarE enzyme activity was up-regulated in 24 h, and then it was decreased compared with the control group. Furthermore, the expressions of the key genes in the PI3K/Akt/CncC signaling pathway (PI3K, PDK, Akt, CncC and Keap1) at the mRNA were significantly increased. Western blotting analysis revealed that Akt was inhibited at the protein level, resulting in decreased expression of Keap1 and increased expression of CncC. These results indicated that the PI3K/Akt/CncC signaling pathway in the fat body of B. mori responded to CAP exposure and regulated the expressions of downstream detoxification enzymes, thus enhancing the detoxifying capability of B. mori.

The mechanism of damage in the midgut of Bombyx mori after chlorantraniliprole exposure.

Silkworm (Bombyx mori) is an economic insect of the Lepidoptera. Chlorantraniliprole (CAP) exposure results in reduced growth and development of B. mori and failure in cocooning, seriously affecting the development of sericulture. To study the mechanisms underlying the damage to silkworm caused by sublethal doses of CAP, we examined the oxidative damage, the activities of digestive enzymes in midgut, and the expressions of midgut-related genes at the mRNA level. We found that CAP exposure inhibited the growth of silkworm, decreased the body mass and caused the accumulation of reactive oxygen species (ROS) [the levels of O2-, H2O2 and lipid peroxidation (MDA) were increased by 1.62-, 1.87- and 1.46-fold, respectively]. Moreover, we also found that the midgut cells were disintegrated, microvilli disappeared, the stroma became thinner, and the chromatin of nucleus became aggregated after CAP exposure by the analysis of transmission electron microscopy (TEM). In addition, the activities of digestive enzymes were dysregulated in midgut (the activities of α-amylase and trypsin were decreased 0.69- and 0.20-fold, respectively). Furthermore, digital gene expression (DGE) profiling analysis revealed that the expressions of oxidative phosphorylation pathway and antioxidant defense system related genes in midgut were decreased, indicating that it was the oxidative damage in midgut caused by CAP that mainly affected the growth of silkworm, rather than the toxicological effects of CAP. Collectively, this study provided valuable insights into the toxic effects of CAP on insects.

The mechanism of damage by trace amounts of acetamiprid to the midgut of the silkworm, Bombyx mori.

Acetamiprid is widely used for agricultural pest control. However, it remains poorly understood whether the environmental residues of acetamiprid have the potential effects on economic insect. In this study, we evaluated the effects of acetamiprid on silkworm growth and development. The exposure to trace amounts of acetamiprid significantly decreased body weight, viability, and spinning ability. In addition, the activity of trypsin in the midgut was decreased after exposure. DGE and KEGG pathway enrichment analysis revealed that the significantly differentially expressed genes were mainly involved in nutrient metabolism, stress responses, and inflammation pathways. These results, in combination with hematoxylin-eosin staining and transmission electron microscopy, indicated that acetamiprid could cause oxidative damage to midgut, lead to inflammatory responses, and affect the activities of midgut digestive enzymes, thus resulting in abnormal growth and development. Our findings greatly contributed to the evaluation of the effects of acetamiprid residues on other nontarget beneficial insect.

Developing CAR-immune cell therapy against SARS-CoV-2: Current status, challenges and prospects.

Chimeric antigen receptor (CAR)-immune cell therapy has revolutionized the anti-tumor field, achieving efficient and precise tumor clearance by directly guiding immune cell activity to target tumors. In addition, the use of CAR-immune cells to influence the composition and function of the immune system and ultimately achieve virus clearance and immune system homeostasis has attracted the interest of researchers. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) triggered a global pandemic of coronavirus disease 2019 (COVID-19). To date, the rapidly mutating SARS-CoV-2 continues to challenge existing therapies and has raised public concerns regarding reinfection. In patients with COVID-19, the interaction of SARS-CoV-2 with the immune system influences the course of the disease, and the coexistence of over-activated immune system components, such as macrophages, and severely compromised immune system components, such as natural killer cells, reveals a dysregulated immune system. Dysregulated immune-induced inflammation may impair viral clearance and T-cell responses, causing cytokine storms and ultimately leading to patient death. Here, we summarize the research progress on the use of CAR-immune cells against SARS-CoV-2 infection. Furthermore, we discuss the feasibility, challenges and prospect of CAR-immune cells as a new immune candidate therapy against SARS-CoV-2.

Epigenetic Regulatory Axis MIR22-TET3-MTRNR2L2 Represses Fibroblast-Like Synoviocyte-Mediated Inflammation in Rheumatoid Arthritis.

OBJECTIVE: The specific role of fibroblast-like synoviocytes (FLSs) in the pathogenesis of rheumatoid arthritis (RA) is still not fully elucidated. This study aimed to explore the molecular mechanisms of epigenetic pathways, including three epigenetic factors, microRNA (miRNA)-22 (MIR22), ten-eleven translocation methylcytosine dioxygenase 3 (TET3), and MT-RNR2 like 2 (MTRNR2L2), in RA-FLSs. METHODS: The expression of MIR22, TET3, and MTRNR2L2 in the synovium of patients with RA and arthritic mice were determined by fluorescence in situ hybridization, quantitative polymerase chain reaction (qPCR), immunohistochemistry, and Western blot. Mir22-/- and Tet3+/- mice were used to establish a collagen antibody-induced arthritis (CAIA) model. Mir22 angomir and Tet3 small interfering RNA (siRNA) were used to illustrate the therapeutic effects on arthritis using a collagen-induced (CIA) model. Bioinformatics, luciferase reporter assay, 5-hydroxymethylcytosine (5hmC) dot blotting, chromatin immunoprecipitation-qPCR, and hydroxymethylated DNA immunoprecipitation were conducted to show the direct repression of MIR22 on the TET3 and transcriptional activation of TET3 on MTRNR2L2. RESULTS: The Mir22-/- CAIA model and RA-FLS-related in vitro experiments demonstrated the inhibitory effect of MIR22 on inflammation. MIR22 can directly inhibit the translation of TET3 in RA-FLSs by binding to its 3' untranslated region in TET3. The Tet3+/- mice-established CAIA model showed less severe symptoms of arthritis in vivo. In vitro experiments further confirmed the proinflammatory effect of TET3 in RA. In addition, the CIA model was used to validate the therapeutic effects of Mir22 angomir and Tet3 siRNA. Finally, TET3 exerts its proinflammatory effect by promoting 5hmC production in the promoter of its target MTRNR2L2 in RA-FLSs. CONCLUSION: The key role of the MIR22-TET3-MTRNR2L2 pathway in RA-FLSs provided an experimental basis for further studies into the pathogenesis and related targets of RA from the perspective of FLSs.

Interaction of tumor-associated microglia/macrophages and cancer stem cells in glioma.

Glioma is the most common tumor of the primary central nervous system, and its malignant phenotype has been shown to be closely related to glioma stem cells (GSCs). Although temozolomide has significantly improved the therapeutic outcome of glioma with a high penetration rate of the blood-brain barrier, resistance is often present in patients. Moreover, evidence has shown that the crosstalk between GSCs and tumor-associated microglia/macrophages (TAMs) affect the clinical occurrence, growth, and multi-tolerance of chemoradiotherapy in gliomas. Here, we highlight its vital roles in the maintenance of the stemness of GSCs and the ability of GSCs to recruit TAMs to the tumor microenvironment and promote their polarization into tumor-promoting macrophages, hence providing groundwork for future research into new treatment strategies of cancer.