Denitrification performance and bacterial ecological network of a reactor using biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) as an electron donor for nitrate removal from aquaculture wastewater

Nitrate accumulation is a common phenomenon in aquaculture that can lead to eutrophication of surrounding water bodies. This study used poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) as a carbon source and substrate and performed a microbial co-occurrence network ecological analysis to elucidate the denitrification processes in two packed-bed reactors with different salinities. The denitrification rate reached maximum values of 0.438 and 0.446 kg m^-3 d^-1 in reactor I (salinity 0 ‰) and reactor II (salinity 20 ‰), respectively. Although ammonia was formed in both systems based on dissimilation nitrate reduction to ammonia (DNRA), the concentration was very low (2.47 ± 1.99 and 2.84 ± 1.79 mg L^-1); moreover, the nitrite content was average (1.01 ± 0.87 and 0.96 ± 0.86 mg L^-1). These results suggested that denitrification dominated in both reactors. PHBV generally presented a stable release of DOC, although a sharp increase was observed in the start-up period of reactor II. 16S rRNA results showed that reactor I had richer microbial diversity than reactor II. Among the top ten taxa, Betaproteobacteria was the dominant class in reactor I while Gammaproteobacteria was the dominant class in reactor II. In the stable period, Thauera and Denitromonas was the most abundant genera in reactor I and reactor II, respectively. In addition, the bacterial co-occurrence network showed that reactor I had a more complex node and edge network and faster start-up time compared to reactor II; however, reactor II had a more stable nitrogen removal capacity. Higher expression of NorB and NosZ genes in reactor II indicated higher efficient denitrification in seawater system. The SEM and FTIR showed bacterial development and materials surface erosion. These findings verified the denitrification performance and niche differences between freshwater and seawater environments.

Association of Dental Caries with Muscle Mass, Muscle Strength, and Sarcopenia: A Community-Based Study

OBJECTIVES

Changes in the oral cavity can reflect other changes throughout the body. This study aimed to investigate the association of dental caries with muscle mass, muscle strength, and sarcopenia, and also to describe the microbial diversity, composition, and community structure of severe dental caries and sarcopenia.

DESIGN

Cross-sectional study based on a Chinese population aged from 50 to 85 years.

SETTING

Communities from Lanxi City, Zhejiang Province, China.

PARTICIPANTS

A total of 1,442 participants aged from 50 to 85 years from a general community (62.8% women; median age 61.0 [interquartile range: 55.0, 68.0]).

MEASUREMENTS

Dental caries was assessed by the decayed, missing, and filled teeth (DMFT) index. Sarcopenia was defined as the presence of both low muscle mass (assessed by dual-energy X-ray absorptiometry scanning) and low muscle strength (assessed by handgrip strength). Multivariate logistic regression models were used to analyze the association of dental caries with muscle mass, muscle strength, and sarcopenia. Fecal samples underwent 16S rRNA profiling to evaluate the diversity and composition of the gut microbiota in patients with severe dental caries and/or sarcopenia.

RESULTS

In the fully adjusted logistic models, dental caries was positively associated with low muscle strength (DMFT ≥ 7: OR, 1.61; 95% CI, 1.25-2.06), and sarcopenia (DMFT ≥ 7: OR, 1.51; 95% CI, 1.01-2.26), but not low muscle mass. Severe dental caries was positively associated with higher alpha-diversity indices (richness, chao1, and ACE, all p < 0.05) and associated with beta-diversity based on Bray-Curtis distance (p = 0.006). The severe dental caries group and the sarcopenia group overlapped with 11 depleted and 13 enriched genera.

CONCLUSION

Dental caries was positively associated with low muscle strength and sarcopenia but not muscle mass, and this association was more pronounced in male individuals. Significant differences were observed in gut microbiota composition both in severe dental caries and sarcopenia, and there was an overlap of the genera features. Future longitudinal studies are needed to clarify causal relationships.

Dual-Responsive Hydrogels with Three-Stage Optical Modulation for Smart Windows

Since room temperature management consumes a large amount of building energy, thermochromic smart windows have been extensively used for temperature regulation and energy management. However, the development of the smart window is still limited by its simple thermochromic performance, unreasonable thermochromic temperature, and the lack of additional stimulation conditions. In this work, a dual-responsive hydrogel was developed by introducing sodium dodecyl sulfate (SDS) and sodium chloride into the cross-linking network of poly(N-isopropylacrylamide) (PNIPAM) and polyacrylamide (PAM) for energy-saving and privacy protection. By controlling the temperature from low (<15 °C) to medium (15-28 °C) to high (>28 °C), the dual-responsive hydrogel achieved a reversible three-stage transition of opaque-transparent-translucent. The hydrogel exhibited a satisfactory solar modulation ability (T_lum = 80.3%, ΔT_sol,15-18°C = 72.9%, ΔT_sol,18-35°C = 42.7%) and effective IR and UV shielding at high (or low) temperatures. Moreover, compared with traditional windows, smart windows made of dual-responsive hydrogels could offer better thermal insulation and heat preservation. The electrochromic properties of the dual-responsive hydrogel presented a facile strategy to meet the needs of different situations. The dual-responsive hydrogel features energy-saving, privacy protection, three-stage optical modulation, and multistimulus responsiveness, making it an ideal smart window candidate.

[Efficacy of dienogest versus gonadotropin-releasing hormone agonist combined with dienogest sequential therapy in the treatment of adenomyosis]

Objective: To investigate the efficacy and safety of dienogest (DNG) alone and gonadotropin-releasing hormone agonist (GnRH-a) combined with DNG sequential treatment to adenomyosis. Methods: The clinical data of 110 patients with adenomyosis attending the First Affiliated Hospital of Nanjing Medical University from December 2019 to March 2022 were retrospectively analyzed, including 40 patients treated with DNG (2 mg/day) alone (DNG group) and 70 patients treated with sequential DNG (2 mg/day) after 3-6 injections of GnRH-a (GnRH-a+DNG group). The clinical data before and after treatment were compared between the two groups. Results: (1) The dysmenorrhea visual analogue scale (VAS) scores, cancer antigen 125 (CA₁₂₅) and cancer antigen 19-9 (CA_19-9) levels at different time periods after treatment were significantly lower than before treatment in both groups (median before treatment: DNG group 70.0 mm, 68.55 kU/L, 22.45 kU/L respectively, GnRH-a+DNG group 80.0 mm, 151.50 kU/L, 20.44 kU/L respectively; all P<0.001). (2) The hemoglobin (Hb) levels of patients in both groups at different time periods after treatment were significantly higher than those before treatment (median: DNG group 102.00 g/L, GnRH-a+DNG group 94.00 g/L; all P<0.001). (3) Treatment with DNG alone did not have a significant effect on uterine volume in patients of DNG group (P>0.05), and uterine volume decreased significantly in the 15th-24th months of GnRH-a+DNG group compared with that before treatment (median: 167.76 vs 227.77 cm³; P<0.05). (4) There were no significant differences in hepatic and renal function and coagulation indexes between the two groups before and after treatment (all P>0.05), and no significant abnormal lesions were observed in breast tissue during the follow-up period. (5) The incidence of amenorrhea of GnRH-a+DNG group was higher than that of DNG group, and the incidences of irregular spotting bleeding and breakthrough hemorrhage were lower than those in DNG group. Conclusions: Whether DNG is used alone or in combination with GnRH-a in sequence, it could significantly relieve dysmenorrhea symptoms, improve the level of Hb, reduce the levels of CA₁₂₅ and CA_19-9 in patients with adenomyosis, with no adverse effects on coagulation and hepatic or renal function. GnRH-a sequential DNG therapy is superior to DNG alone in improving uterine bleeding patterns and controlling the growth of uterine volume in patients with adenomyosis.

[A time-series study on the association of ambient temperature with daily outpatient visits of eczema in Huizhou city]

Objective: To explore the impact of environmental temperature exposure on eczema visits. Methods: Eczema clinic data from January 1, 2016 to December 31, 2019 were collected from the Huizhou Dermatology Hospital, and data on meteorological factors (average daily temperature and relative humidity) for the same period were derived from 86 meteorological stations of the Guangdong Provincial Climate Center. A distributed lag nonlinear model (DLNM) was used to assess the lagged effect of environmental temperature exposure on eczema, and a natural smooth spline function was used to control the nonlinear confounding of humidity. Results: There were 254 053 eczema outpatient visits at the Huizhou Dermatology Hospital within four years, with an average of 173.89 visits per day. The relationship between daily average temperature and the number of visits was non-linear (U shape). The risk of eczema increased by 2.20% (1.19%-3.21%) for every 1 ℃ decrease for the low temperature, and increased by 2.35% (1.24%-3.5%) for every 1 ℃ increase for the high temperature. The effect of high temperature was greater than that of low temperature. In all cases, 1.60% (0.44%-2.68%) of eczema outpatient visits were attributed to low temperature and the attributable number was 4 065 (1 128-6 798), while 6.33% (1.40%-10.87%) of eczema outpatient visits were due to high temperature and the attributable number was 16 082 (3 557-27 616). Conclusion: Both high temperature and low temperature are associated with increased risk of eczema.

P04.01.B High impact of ITGB1 on Pi3K/AKT expression in medulloblastoma

Medulloblastoma, an embryonal tumor of the cerebellum, is one of the most frequent malignant brain tumors. Despite the increasing use of genetic variation in treatment stratification, high-risk patients characterized by light meningeal spread, TP53 mutations, or MYC amplification still have poor survival. Phosphatidylinositol-3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) signaling is one of the most important intracellular pathways, which can be considered as a master regulator for cancer. In tissue samples obtained from medulloblastoma patients, the significant upregulation of PI3K/AKT was associated with a lifting expression level of integrin β1(ITGB1). To understand the underlying mechanism, we investigated the effect of ITGB1 on the PI3K/AKT pathway in medulloblastoma cell lines. Transfection of this ITGB1 reduced proliferation and invasion of several medulloblastoma cell lines and inhibit epithelial-mesenchymal transition. In addition, knocking down ITGB1 expression can significantly inhibit the activation of PI3K/AKT signaling pathway. In conclusion, ITGB1 may selectively activation the pathophysiological effect of aberrant PI3K/AKT expression and serve as a targeted approach for medulloblastoma therapy.

OS10.7.A Activation of the CCR8-ACP5 axis by human microglia/macrophage derived CCL18 promotes glioma growth

Background

Glioblastoma multiforme is a highly malignant primary brain tumor with an average survival of 14 months and very limited therapeutic options. Glioma associated microglia and macrophages (GAMs) foster tumor growth by releasing several cytokines, which have only partly been identified. Here, we studied the chemokine (C-C motif) ligand 18 (CCL18), a chemokine which is only expressed in human, but not rodent GAMs, in a novel ex-vivo brain slice model including transplantation of human induced pluripotent stem cells (iPSC) derived human microglia (iMGL) and human glioma cells in to murine brain slices, which had been depleted of intrinsic murine microglia before.

Material and Methods

After establishing the humanized ex-vivo brain slice model, we performed immunohistochemical analysis (IHC) of growth and invasiveness, qrtPCR on glioma cells isolated by magnetic-activated cell sorting (MACS), functional assays measuring invasiveness, proliferation, migration and colony formation of glioma cells in vitro and in slice experiments. Corresponding studies on tumor growth and invasiveness were performed after treatment with a CCL18 neutralizing antibody, a CCR8 neutralizing antibodies and knockdown of CCR8, ACP5 (Acid Phosphatase 5) and PITPNM3 with small interfering RNA (siRNA) and short hairpin RNA (shRNA). QrtPCR, IHC and Westernblot analysis were performed on primary glioma specimens. We also conducted bioinformatic analyses, based on the TCGA GBM, GLIOVIS and GEPIA databases.

Results

We observed that CCL18 was highly expressed in GAMs, whereas CCR8 was only expressed in glioma cells. We identified the chemokine (C-C motif) receptor 8 (CCR8) as a functional receptor for CCL18 and ACP5 as an important down-stream signaling component in glioma cells. Activation of the CCL18/CCR8/ACP5 signaling pathway in human glioblastoma was associated with enhanced tumor growth and invasiveness.

Conclusion

GAMs derived CCL18 promoted glioma growth by activation of the CCR8/ACP5 axis in human glioma cells and therefore is a potential therapeutic target.

Two-year outcomes of Roux-en-Y gastric bypass vs medical treatment in type 2 diabetes with a body mass index lower than 32.5 kg/m2: a multicenter propensity score-matched analysis

BACKGROUND

Roux-en-Y gastric bypass (RYGB) has been widely reported to be safe and feasible, and has a powerful effect on improving metabolism and weight loss in patients with a high body mass index (BMI). A few studies have focused on the comparison of RYGB with medical treatment in type 2 diabetes (T2D) patients with a lower BMI.

OBJECTIVES

To compare the metabolic effects and safety of RYGB versus medical treatment during a 2 years follow-up in T2D patients with a BMI of 25 to 32.5 kg/m².

METHODS

This retrospective and multicenter cohort study participants were extracted from the T2D patients with a lower BMI (25-32.5 kg/m²) from three bariatric centers between 2009 and 2018. Propensity score matching (PSM) was used to minimize bias, and each patient in the surgical group was matched 1:2 to the patients in the medical group with the closest propensity score. Finally, 71 patients who received RYGB and 142 patients who underwent medical treatment with a 2 years follow-up were enrolled to compare the effects of RYGB and medical treatment. The primary endpoint was achievement of the triple endpoint (the simultaneous achievement of hemoglobin A1c (HbA1c) < 7.0%, fasting low-density lipoprotein cholesterol (LDL-C) < 100 mg/dL (2.6 mmol/L), and systolic blood pressure (SBP) < 130 mmHg at the year-1 visit). Changes in weight, BMI, medication usage, complications, and adverse events were assessed.

RESULTS

In total, 213 patients (mean age of 47.4 ± 9.5 years, 70.4% male, mean BMI of 28.6 ± 2.2 kg/m²) were included in this study. At the end of the first year, 17 patients (23.9%) in the surgical group and 10 (7.0%) in the medical group had achieved the composite triple endpoint (OR 4.64; 95% CI 1.82-11.81; p = 0.001). Additionally, 43 patients (60.6%) in the surgical group and 11 patients (19.7%) in the medical group experienced remission of T2D. However, more complications were observed in the surgical group (36 vs. 22, p < 0.01).

CONCLUSIONS

Among T2D patients with a BMI between 25.0 and 32.5 kg/m², RYGB was more effective than medical treatment in resolving metabolic disorders and also resulted in more complications. The risk for complications should be considered in the clinical decision-making process for T2D patients with a low BMI.

Synergistic effect of chitosan-based sludge aggregates CS@NGS inoculum accelerated the start-up of biofilm reactor treating aquaculture effluent: Insights into performance, microbial characteristics, and functional genes

The moving bed bioreactor (MBBR) process has drawn more attention as a promising biological wastewater treatment process. Nevertheless, achieving quick start-up and microbial biofilm formation remains a significant challenge. Consequently, the present study investigated a novel chitosan-based natural sludge (CS@NGS) seeding strategy for the accelerated start-up of MBBR. Three identical bioreactors were employed; the first bioreactor was without sludge seed as the control (BR1), the second was inoculated only with sludge (BR2), and the third was inoculated with CS@NGS according to the proposed seeding method (BR3). All bioreactors were utilised to treat simulated recirculating aquaculture systems (RAS) effluent. Resultantly, the CS@NGS shortened the start-up period from over twenty to seven days due to the enhanced initial microbial adhesion and biofilm formation. Under optimal conditions, the ammonium removal in BR3 approached 100%, which was relatively higher than BR2 (96.35 ± 1.12%) and BR1 (92.56 ± 2.17%). Moreover, a low nitrite accumulation was exhibited in the effluents, approximately ≤0.03 mg L^-1. The process performance correlated positively with core bacteria from the genera Nakamurella, Hyphomicrobium, Nitrospira, Paenarthrobacter, Rhodococcus, and Stenotrophobacter. The quantitative polymerase chain reaction (qPCR) results demonstrated that the CS@NGS enhanced the expressions of amoA, nxrB, nirK, nirS, narG, and napA nitrogen metabolism-related functional genes to varying degrees. The present study findings can assist the rapid start-up of aquaculture biofilters utilised to solve high nitrite and ammonia accumulation in recirculated water from industrial RAS.

[Prolonged epidural labor analgesia increases risks of epidural analgesia failure for conversion to cesarean section]

OBJECTIVE

To explore the effect of epidural labor analgesia duration on the outcomes of different anesthetic approaches for conversion to cesarean section.

METHODS

We retrospectively collected the clinical data of pregnant women undergoing conversion from epidural labor analgesia to cesarean section at Sichuan Maternal and Child Health Hospital and Jinjiang District Maternal and Child Health Care Hospital between July, 2019 and June, 2020. For cesarean section, the women received epidural anesthesia when the epidural catheter was maintained in correct position with effective analgesia, spinal anesthesia at the discretion of the anesthesiologists, or general anesthesia in cases requiring immediate cesarean section or following failure of epidural anesthesia or spinal anesthesia. Receiver-operating characteristic curve analysis was performed to determine the cutoff value of the analgesia duration using Youden index. The women were divided into two groups according to the cut off value for analyzing the relative risk using cross tabulations.

RESULTS

A total of 820 pregnant women undergoing conversion to cesarean section were enrolled in this analysis, including 615 (75.0%) in epidural anesthesia group, 186 (22.7%) in spinal anesthesia group, and 19 (2.3%) in general anesthesia group; none of the women experienced failure of epidural or spinal anesthesia. The mean anesthesia duration was 8.2±4.7 h in epidural anesthesia, 10.6±5.1 h in spinal anesthesia group, and 6.7 ± 5.2 h in general anesthesia group. Multivariate logistic regression analysis showed that prolongation of analgesia duration by 1 h (OR=1.094, 95% CI: 1.057-1.132, P < 0.001) and an increase of cervical orifice by 1 cm (OR=1.066, 95% CI: 1.011-1.124, P=0.017) were independent risk factors for epidural analgesia failure. The cutoff value of analgesia duration was 9.5 h, and beyond that duration the relative risk of receiving spinal anesthesia was 1.204 (95% CI: 1.103-2.341, P < 0.001).

CONCLUSION

Prolonged epidural labor analgesia increases the risk of failure of epidural analgesia for conversion to epidural anesthesia. In cases with an analgesia duration over 9.5 h, spinal anesthesia is recommended if immediate cesarean section is not required.

CO2 fluxes from three different temperate grazed pastures using Eddy covariance measurements

Grasslands cover around 25% of the global ice-free land surface, they are used predominantly for forage and livestock production and are considered to contribute significantly to soil carbon (C) sequestration. Recent investigations into using 'nature-based solutions' to limit warming to <2 °C suggest up to 25% of GHG mitigation might be achieved through changes to grassland management. In this study we evaluate pasture management interventions at the Rothamsted Research North Wyke Farm Platform, under commercial farming conditions, over two years and consider their impacts on net CO₂ exchange. We investigate if our permanent pasture system (PP) is, in the short-term, a net sink for CO₂ and whether reseeding this with deep-rooting, high-sugar grass (HS) or a mix of high-sugar grass and clover (HSC) might increase the net removal of atmospheric CO₂. In general CO₂ fluxes were less variable in 2018 than in 2017 while overall we found that net CO₂ fluxes for the PP treatment changed from a sink in 2017 (-5.40 t CO₂ ha^-1 y^-1) to a source in 2018 (6.17 t CO₂ ha^-1 y^-1), resulting in an overall small source of 0.76 t CO₂ ha^-1 over the two years for this treatment. HS showed a similar trend, changing from a net sink in 2017 (-4.82 t CO₂ ha^-1 y^-1) to a net source in 2018 (3.91 t CO₂ ha^-1 y^-1) whilst the HSC field was a net source in both years (3.92 and 4.10 t CO₂ ha^-1 y^-1, respectively). These results suggested that pasture type has an influence in the atmospheric CO₂ balance and our regression modelling supported this conclusion, with pasture type and time of the year (and their interaction) being significant factors in predicting fluxes.

[Changes of coagulation function in patients with adenomyosis]

Objective: To explore the different coagulation state in patients with adenomyosis and its clinical significance. Methods: Clinical data of the patients admitted to the First Affiliated Hospital of Nanjing Medical University from January 2017 to December 2021 were retrospectively analyzed. (1) Differential coagulation state between 25 healthy women and 25 patients with adenomyosis were compared during menstrual and non-menstrual periods. (2) The coagulation indexes of 145 patients with adenomyosis (observation group 1) and 129 patients with cervical intraepithelial neoplasia grade Ⅲ (control group 1) who underwent hysterectomy in non-menstrual period were compared. (3) The coagulation indexes of 154 patients with adenomyosis (observation group 2) and 147 women without myometrial lesions (control group 2) who underwent endometrial curettage during uterine bleeding period were compared. (4) Correlations of coagulation index with cancer antigen 125 (CA₁₂₅), cancer antigen 19-9 (CA_19-9) and uterine volume in patients with adenomyosis were analyzed. Results: (1) The coagulation state of each health women during the menstrual and non-menstrual period showed no significant differences (all P>0.05). For the 25 patients with adenomyosis, fibrinogen [FIB; 2.61 g/L(2.50-3.10 g/L)] and D-dimer [0.60 mg/L (0.40-1.00 mg/L)] in the menstrual period were significantly higher than those in the non-menstrual period [2.25 g/L (1.90-2.70 g/L) and 0.27 mg/L (0.20-0.40 mg/L), respectively; both P<0.01], while thrombin time [TT; 16.70 s (16.10-17.40 s)] in the menstrual period was significantly lower than that in the non-menstrual period [17.95 s (17.20-18.40 s); P<0.01]. (2) In the non-bleeding period, D-dimer [0.26 mg/L (0.20-0.40 mg/L)] and platelet count [257.0×10⁹/L (212.0×10⁹/L-308.5×10⁹/L)] of observation group 1 were significantly higher than those of control group 1 (all P<0.01). Besides, FIB (r=0.237, P=0.004) and D-dimer (r=0.373, P<0.001) were positively correlated with CA₁₂₅, while prothrombin time (PT; r=-0.208, P=0.012) and internationalized normalized ratio of plasma prothrombin time (PT-INR; r=-0.201, P=0.015) were negatively correlated with CA_19-9. (3) In the bleeding period, PT [10.70 s (10.10-11.20 s)] and PT-INR [0.93 (0.90-1.00)] of observation group 2 were significantly lower than those of control group 2 (all P<0.01), while D-dimer [0.41 mg/L (0.20-0.80 mg/L)] was significantly higher than that in the control group 2 (P<0.001). Furthermore, FIB (r=0.252, P=0.038) and D-dimer (r=0.321, P=0.008) were positively correlated with uterine volume, while activated partial thromboplastin time (APTT; r=-0.190, P=0.018) and TT (r=-0.304, P=0.012) were negatively correlated with uterine volume. (4) During non-menstrual period and uterine bleeding period, APTT and TT in patients of observation group 1 and 2 combined with anemia were significantly lower than those of non-anemia patients (all P<0.05). Conclusion: Patients with adenomyosis have a tendency to hypercoagulability in both the uterine bleeding and non-bleeding periods, which may be related to enlarged uterine volume, increased serum CA₁₂₅ and anemia.

[Research advances in the treatment of liver failure with mesenchymal stem cell-derived exosomes]

Liver failure is a serious clinical syndrome in which multiple pathogenic factors exceed the liver's self-repair capability, resulting massive hepatocellular necrosis, rapid disease progression and high mortality. Liver transplantation is the most effective method for the treatment of liver failure, but it has disadvantages, such as insufficient liver donor and high cost. The clinical efficacy of mesenchymal stem cells in liver failure have been validated, but its application has been limited to certain extent. Cell-free-based therapies, especially mesenchymal stem cell-derived exosomes, has become a research hotspot in recent years. This paper reviews the research advances in the treatment of liver failure with the use of mesenchymal stem cell-derived exosomes.

Exosomes derived from stem cells from the apical papilla alleviate inflammation in rat pulpitis by upregulating regulatory T cells

AIM

To evaluate the effects of exosomes derived from stem cells from the apical papilla (SCAP-Exos) in rats with experimentally induced pulpitis and the effects of SCAP-Exos on the conversion of regulatory T cells (Tregs) and methylation status of the Foxp3 locus in Tregs in vitro.

METHODOLOGY

SCAP-Exos were isolated and identified using transmission electron microscopy, western blotting, and nanoparticle tracking analysis. Lipopolysaccharide was used to experimentally induced pulpitis in rats, and the effects of SCAP-Exos on the rats with pulpitis were detected using haematoxylin-eosin staining and immunofluorescence staining. CD4+CD25- T cells were treated with different doses of SCAP-Exos, and flow cytometric analysis was used to assess the effects of SCAP-Exos on Treg proliferation and conversion. An enzyme-linked immunosorbent assay (ELISA) was used to evaluate the expression of interleukin 10 (IL-10). MethylTarget^® technology was used to measure the methylation level of the Foxp3 locus in T cells. The expression levels of ten-eleven-translocation (Tet) 1, Tet2, and Tet3 in T cells were detected by real-time PCR and western blotting.

RESULTS

SCAP-Exos had an elliptical vesicle-like structure with a diameter of approximately 143.7 nm and expressed the exosomal markers Alix and CD9. SCAP-Exo administration increased Treg accumulation in the inflamed dental pulp and alleviated inflammation in the dental pulp in vivo. SCAP-Exos promoted Treg conversion in vitro. Mechanistically, SCAP-Exos promoted Tet2-mediated Foxp3 demethylation to maintain the stable expression of Foxp3.

CONCLUSIONS

SCAP-Exos promoted Treg conversion and effectively alleviated inflammation in the dental pulp of rats. This study shows that SCAP-Exos can regulate the local immune microenvironment to favour tissue regeneration, thus providing a potential novel strategy utilising SCAP-Exos as a cell-free approach to treat early inflammation of dental pulp in immature permanent teeth in the clinic.