Roles of different Ni-Si interactions in methane combustion under oscillating temperature conditions.

The silicon- modified nickel oxide catalysts with the same compositions but distinct Ni-Si interactions were obtained via different synthesis routes and utilized for methane combustion under conditions of oscillating temperatures. For catalysts prepared by co-grinding, amorphous SiO2 was dispersed on the surface of large NiO crystallites. During high-temperature calcination or reactions, the crystallization of SiO2, coupled with the sintering or decomposition of NiO crystallites, led to the inferior catalytic activity and stability. Interactions between Ni and Si species were enhanced in catalysts synthesized by precipitation. The Si species was incorporated into the NiO lattice to inhibit the growth of NiO crystallites and to generate nickel silicate species under thermal treatments. The small NiO crystallites provided more Ni3+ and active oxygen species for methane activation and oxidation, while the bulk nickel silicate species played a pivotal role in improving thermal stability, conjointly provoking excellent catalytic performance in cyclic heating-cooling tests between 180 and 800 °C. This study offers new insights into the design of metal oxide composites for catalytic applications.

Factors Associated with Mortality Among Severe Omicron Patients for COVID-19.

Purpose: The purpose of the study was to explore the potential risk factors of mortality in patients with severe pneumonia during the omicron pandemic in South China in 2022. Methods: Clinical data was collected from patients hospitalized with omicron COVID-19. Then, patients were categorized into the non-survival and survival groups. A comprehensive analysis was conducted to analyze the factors associated with negative outcome in individuals suffering from severe omicron COVID-19. Results: In this study, 155 severe COVID-19 patients were included, comprising 55 non-survivors and 100 survivors. Non-survivors, in comparison to survivors, exhibited elevated levels of various biomarkers including neutrophil count, hypersensitive troponin T, urea, creatinine, C-reactive protein, procalcitonin, interleukin-6, plasma D-dimer, and derived neutrophil-to-lymphocyte ratio (dNLR) (P < 0.05). They also displayed reduced lymphocyte count, platelet count, and albumin levels (P < 0.05) and were more prone to developing comorbidities, including shock, acute cardiac and renal injury, acute respiratory distress syndrome, coagulation disorders, and secondary infections. Platelet count (PLT) <100 × 10^/L, interleukin-6 (IL-6) >100 pg/mL, and dNLR >5.0 independently contributed to the risk of death in patients suffering from severe COVID-19. Conclusion: PLT, IL-6, and dNRL independently contributed to the risk of mortality in patients with severe pneumonia during the 2022 omicron pandemic in South China.

mTOR signaling promotes rapid m6A mRNA methylation to regulate NK-cell activation and effector functions.

Natural killer (NK) cells can be rapidly activated in response to cytokines during host defense against malignant cells or viral infection. However, it remains unclear what mechanisms precisely and rapidly regulate the expression of the numerous genes involved in activating NK cells. In this study, we discovered that NK-cell N6-methyladenosine (m6A) methylation levels were rapidly upregulated upon short-term NK-cell activation and were repressed in the tumor microenvironment. Deficiency of methyltransferase-like 3 (METTL3) or METTL14 moderately influenced NK-cell homeostasis, while double knockout of METTL3/14 significantly impacted NK-cell homeostasis, maturation, and antitumor immunity. This suggests a cooperative role of METTL3 and METTL14 in regulating NK-cell development and effector functions. Using methylated RNA immunoprecipitation sequencing (MeRIP-seq), we demonstrated that genes involved in NK-cell effector functions, such as Prf1 and Gzmb, were directly modified by m6A methylation. Furthermore, inhibiting mTOR complex 1 (mTORC1) activation prevented m6A methylation levels from increasing when NK cells were activated, and this could be restored by S-adenosylmethionine (SAM) supplementation. Collectively, we have unraveled crucial roles for rapid m6A mRNA methylation downstream of the mTORC1-SAM signal axis in regulating NK-cell activation and effector functions.

Prognostic factors and treatment responses among patients with gross residual disease in differentiated thyroid cancer.

BACKGROUND: Various postoperative staging systems were developed to assess the outcome of differentiated thyroid cancer (DTC) from initial risk after surgery to dynamic changing prognosis during follow-up. The objective of our retrospective cohort study was to identify risk factors contributing to macroscopic positive surgical margin (R2 resection) and parameters in discriminating the treatment responses and prognosis among R2 patients. METHODS: In total, 242 DTC patients with extrathyroidal extension who underwent a thyroidectomy at Kaohsiung Chang Gung Memorial Hospital between January 2013 and July 2018, were included. The patients were grouped according to the presence or absence of gross residual disease (R2). The R2 patients were further classified into two categories according to their treatment response into excellent and non-excellent groups. The parameters and treatment outcomes were compared between these groups. RESULTS: The mean follow-up time was 45.3 months. 207 (85.5%) patients had either surgery-free or microscopic margins (R0/R1), while 35 (14.5%) had R2 resection. In the R2 group (n = 35), 15 (42.9%) patients achieved an excellent response, while 20 (57.1%) achieved a non-excellent response. Statistically significant differences were observed in the extent of neck dissection, TSH-Tg level, post-RAI Tg level, nodal status, and recurrence between the two groups. The Kaplan-Meier curves for 5-year local and distant recurrence-free survival (LRFS and DRFS) of R0/R1 vs. R2 patients were 90.0% vs. 66.3%, and 98.4% vs.90.7% respectively, (p <0.001). Among the R2 patients, the excellent responders had a higher LRFS than non-excellent responders (93.3% vs. 45.1%, p=0.008). CONCLUSION: There are significant disparities in RFS among R2 patients with different treatment responses. The nodal status of PTC and thyroglobulin level after thyroidectomy and RAI were factors contributing to difference in their treatment responses.

Research progress on optimization of in vitro isolation, cultivation and preservation methods of dental pulp stem cells for clinical application.

Due to high proliferative capacity, multipotent differentiation, immunomodulatory abilities, and lack of ethical concerns, dental pulp stem cells (DPSCs) are promising candidates for clinical application. Currently, clinical research on DPSCs is in its early stages. The reason for the failure to obtain clinically effective results may be problems with the production process of DPSCs. Due to the different preparation methods and reagent formulations of DPSCs, cell characteristics may be affected and lead to inconsistent experimental results. Preparation of clinical-grade DPSCs is far from ready. To achieve clinical application, it is essential to transit the manufacturing of stem cells from laboratory grade to clinical grade. This review compares and analyzes experimental data on optimizing the preparation methods of DPSCs from extraction to resuscitation, including research articles, invention patents and clinical trials. The advantages and disadvantages of various methods and potential clinical applications are discussed, and factors that could improve the quality of DPSCs for clinical application are proposed. The aim is to summarize the current manufacture of DPSCs in the establishment of a standardized, reliable, safe, and economic method for future preparation of clinical-grade cell products.

Low concentrations of TNF-α in vitro transform the phenotype of vascular smooth muscle cells and enhance their survival in a three-dimensional culture system.

BACKGROUND: Vascular smooth muscle cells (VSMCs) are commonly used as seed cells in tissue-engineered vascular constructions. However, their variable phenotypes and difficult to control functions pose challenges. This study aimed to overcome these obstacles using a three-dimensional culture system. METHODS: Calf VSMCs were administered tumor necrosis factor-alpha (TNF-α) before culturing in two- and three-dimensional well plates and polyglycolic acid (PGA) scaffolds, respectively. The phenotypic markers of VSMCs were detected by immunofluorescence staining and western blotting, and the proliferation and migration abilities of VSMCs were detected by CCK-8, EDU, cell counting, scratch, and Transwell assays. RESULTS: TNF-α rapidly decreased the contractile phenotypic markers and elevated the synthetic phenotypic markers of VSMCs, as well as markedly increasing the proliferation and migration ability of VSMCs under two- and three-dimensional culture conditions. CONCLUSIONS: TNF-α can rapidly induce a phenotypic shift in VSMCs and change their viability on PGA scaffolds.

col1a2+ fibroblasts/muscle progenitors finetune xanthophore countershading by differentially expressing csf1a/1b in embryonic zebrafish.

Animals evolve diverse pigment patterns to adapt to the natural environment. Countershading, characterized by a dark-colored dorsum and a light-colored ventrum, is one of the most prevalent pigment patterns observed in vertebrates. In this study, we reveal a mechanism regulating xanthophore countershading in zebrafish embryos. We found that csf1a and csf1b mutants altered xanthophore countershading differently: csf1a mutants lack ventral xanthophores, while csf1b mutants have reduced dorsal xanthophores. Further study revealed that csf1a is expressed throughout the trunk, whereas csf1b is expressed dorsally. Ectopic expression of csf1a or csf1b in neurons attracted xanthophores into the spinal cord. Blocking csf1 signaling by csf1ra mutants disrupts spinal cord distribution and normal xanthophores countershading. Single-cell RNA sequencing identified two col1a2+ populations: csf1ahighcsf1bhigh muscle progenitors and csf1ahighcsf1blow fibroblast progenitors. Ablation of col1a2+ fibroblast and muscle progenitors abolished xanthophore patterns. Our study suggests that fibroblast and muscle progenitors differentially express csf1a and csf1b to modulate xanthophore patterning, providing insights into the mechanism of countershading.

Insulin-transferrin-selenium promote formation of tissue-engineered vascular grafts in early stage of culture.

To create tissue-engineered vascular grafts (TEVGs) in vitro, vascular smooth muscle cells (VSMCs) must function effectively and produce sufficient extracellular matrix (ECM) in a three-dimensional space. In this study, we investigated whether the addition of insulin-transferrin-selenium (ITS), a medium supplement, could enhance TEVG formation. PGA fabric was used as the scaffold, and 1% ITS was added to the medium. After two weeks, the tissues were examined using electron microscopy and staining. The ITS group exhibited a denser structure and increased collagen production. VSMCs were cultured in two dimensions with ITS and assessed for collagen production, cell growth, and glucose metabolism. The results showed that ITS supplementation increased collagen production, cell growth, glucose utilization, lactate production, and ATP levels. Furthermore, reducing the amount of fetal bovine serum (FBS) in the medium did not affect the TEVGs or VSMCs when ITS was present. In conclusion, ITS improves TEVG construction by promoting VSMCs growth and reducing the need for FBS.

The ω-3 polyunsaturated fatty acid docosahexaenoic acid enhances NK-cell antitumor effector functions.

ω-3 polyunsaturated fatty acids (PUFAs) are known to directly repress tumour development and progression. In this study, we explored whether docosahexaenoic acid (DHA), a type of ω-3 PUFA, had an immunomodulatory role in promoting tumour growth in immunocompetent mice. The number of natural killer (NK) cells but not the number of T or B cells was decreased by DHA supplementation in various tissues under physiological conditions. Although the frequency and number of NK cells were comparable, IFN-γ production by NK cells in both the spleen and lung was increased in DHA-supplemented mice in the mouse B16F10 melanoma tumour model. Single-cell RNA sequencing (scRNA-seq) revealed that DHA promoted effector function and oxidative phosphorylation in NK cells but had no obvious effects on other immune cells. Using Rag2-/- mice and NK-cell depletion by PK136 antibody injection, we demonstrated that the suppression of B16F10 melanoma tumour growth in the lung by DHA supplementation was dependent mainly on NK cells. In vitro experiments showed that DHA directly enhanced IFN-γ production, CD107a expression and mitochondrial oxidative phosphorylation (OXPHOS) activity, and slightly increased proliferator-activated receptor gamma coactivator-1α (PGC-1α) protein expression in NK cells. The PGC-1α inhibitor SR-18292 in vitro and NK cell-specific knockout of PGC-1α in mice reversed the antitumour effects of DHA. In summary, our findings broaden the current knowledge on how DHA supplementation protects against cancer growth from the perspective of immunomodulation by upregulating PGC-1α signalling-mediated mitochondrial OXPHOS activity in NK cells.

Single-cell landscape of the cellular microenvironment in three different colonic polyp subtypes in children.

BACKGROUND: The understanding of the heterogeneous cellular microenvironment of colonic polyps in paediatric patients with solitary juvenile polyps (SJPs), polyposis syndrome (PJS) and Peutz-Jeghers syndrome (PJS) remains limited. METHODS: We conducted single-cell RNA sequencing and multiplexed immunohistochemistry (mIHC) analyses on both normal colonic tissue and different types of colonic polyps obtained from paediatric patients. RESULTS: We identified both shared and disease-specific cell subsets and expression patterns that played important roles in shaping the unique cellular microenvironments observed in each polyp subtype. As such, increased myeloid, endothelial and epithelial cells were the most prominent features of SJP, JPS and PJS polyps, respectively. Noticeably, memory B cells were increased, and a cluster of epithelial-mesenchymal transition (EMT)-like colonocytes existed across all polyp subtypes. Abundant neutrophil infiltration was observed in SJP polyps, while CX3CR1hi CD8+ T cells and regulatory T cells (Tregs) were predominant in SJP and JPS polyps, while GZMAhi natural killer T cells were predominant in PJS polyps. Compared with normal colonic tissues, myeloid cells exhibited specific induction of genes involved in chemotaxis and interferon-related pathways in SJP polyps, whereas fibroblasts in JPS polyps had upregulation of myofiber-associated genes and epithelial cells in PJS polyps exhibited induction of a series of nutrient absorption-related genes. In addition, the TNF-α response was uniformly upregulated in most cell subsets across all polyp subtypes, while endothelial cells and fibroblasts separately showed upregulated cell adhesion and EMT signalling in SJP and JPS polyps. Cell-cell interaction network analysis showed markedly enhanced intercellular communication, such as TNF, VEGF, CXCL and collagen signalling networks, among most cell subsets in polyps, especially SJP and JPS polyps. CONCLUSION: These findings strengthen our understanding of the heterogeneous cellular microenvironment of polyp subtypes and identify potential therapeutic approaches to reduce the recurrence of polyps in children.

Interplay of Zeb2a, Id2a and Batf3 regulates microglia and dendritic cell development in the zebrafish brain.

In vertebrates, the central nervous system (CNS) harbours various immune cells, including parenchymal microglia, perivascular macrophages and dendritic cells, which act in coordination to establish an immune network to regulate neurogenesis and neural function, and to maintain the homeostasis of the CNS. Recent single cell transcriptomic profiling has revealed that the adult zebrafish CNS contains microglia, plasmacytoid dendritic cells (pDCs) and two conventional dendritic cells (cDCs), ccl35+ cDCs and cnn3a+cDCs. However, how these distinct myeloid cells are established in the adult zebrafish CNS remains incompletely defined. Here, we show that the Inhibitor of DNA binding 2a (Id2a) is essential for the development of pDCs and cDCs but is dispensable for the formation of microglia, whereas the Basic leucine zipper transcription factor ATF-like 3 (Batf3) acts downstream of id2a and is required exclusively for the formation of the cnn3a+ cDC subset. In contrast, the Zinc finger E-box-binding homeobox 2a (Zeb2a) promotes the expansion of microglia and inhibits the DC specification, possibly through repressing id2a expression. Our study unravels the genetic networks that govern the development of microglia and brain-associated DCs in the zebrafish CNS.

Implications of variable synaptic weights for rate and temporal coding of cerebellar outputs.

Purkinje cell (PC) synapses onto cerebellar nuclei (CbN) neurons allow signals from the cerebellar cortex to influence the rest of the brain. PCs are inhibitory neurons that spontaneously fire at high rates, and many PC inputs are thought to converge onto each CbN neuron to suppress its firing. It has been proposed that PCs convey information using a rate code, a synchrony and timing code, or both. The influence of PCs on CbN neuron firing was primarily examined for the combined effects of many PC inputs with comparable strengths, and the influence of individual PC inputs has not been extensively studied. Here, we find that single PC to CbN synapses are highly variable in size, and using dynamic clamp and modeling we reveal that this has important implications for PC-CbN transmission. Individual PC inputs regulate both the rate and timing of CbN firing. Large PC inputs strongly influence CbN firing rates and transiently eliminate CbN firing for several milliseconds. Remarkably, the refractory period of PCs leads to a brief elevation of CbN firing prior to suppression. Thus, individual PC-CbN synapses are suited to concurrently convey rate codes and generate precisely timed responses in CbN neurons. Either synchronous firing or synchronous pauses of PCs promote CbN neuron firing on rapid time scales for nonuniform inputs, but less effectively than for uniform inputs. This is a secondary consequence of variable input sizes elevating the baseline firing rates of CbN neurons by increasing the variability of the inhibitory conductance. These findings may generalize to other brain regions with highly variable inhibitory synapse sizes.

Anti-inflammatory effect of dental pulp stem cells.

Dental pulp stem cells (DPSCs) have received a lot of attention as a regenerative medicine tool with strong immunomodulatory capabilities. The excessive inflammatory response involves a variety of immune cells, cytokines, and has a considerable impact on tissue regeneration. The use of DPSCs for controlling inflammation for the purpose of treating inflammation-related diseases and autoimmune disorders such as supraspinal nerve inflammation, inflammation of the pulmonary airways, systemic lupus erythematosus, and diabetes mellitus is likely to be safer and more regenerative than traditional medicines. The mechanism of the anti-inflammatory and immunomodulatory effects of DPSCs is relatively complex, and it may be that they themselves or some of the substances they secrete regulate a variety of immune cells through inflammatory immune-related signaling pathways. Most of the current studies are still at the laboratory cellular level and animal model level, and it is believed that through the efforts of more researchers, DPSCs/SHED are expected to be transformed into excellent drugs for the clinical treatment of related diseases.

Nomogram incorporating Epstein-Barr virus DNA and a novel immune-nutritional marker for survival prediction in nasopharyngeal carcinoma.

BACKGROUND: Since Immune response, nutritional status and Epstein-Barr Virus (EBV) DNA status have been confirmed to be relevant to the prognosis of patients with nasopharyngeal carcinoma (NPC), we believe that the combination of these factors is of great value for improving the predictive ability. LA (lymphocytes × albumin), a novel indicator, had not been studied yet in NPC. We combined it with EBV DNA and used nomograms to increase the accuracy of prognosis. METHODS: A total of 688 NPC patients were retrospectively reviewed and further divided into training and validation cohort randomly. Kaplan-Meier analyses were used to to distinguish the different survival outcomes. Multivariate Cox analyses were used to identify the independent prognostic factors for progression-free survival (PFS) and overall survival (OS). Calibration curves, concordance indexes (C-indexes) and decision curve analyses (DCA) were used to evaluate the nomograms' predictive value. RESULTS: Patients with low LA and positive EBV DNA correlated with poorer 5-year PFS and OS (all P < 0.005). In multivariate Cox analyses, LA and EBV DNA were both confirmed to be independent prognostic factors for PFS and OS (all P < 0.05). Prognostic nomograms incorporating LA and EBV DNA achieved ideal C-indexes of 0.69 (95% CI: 0.65-0.73) and 0.77 (95% CI: 0.71-0.82) in the prediction of PFS and OS. Otherwise, the calibration curves and DCA curves also revealed that our nomograms had pleasant predictive power. CONCLUSIONS: LA is a novel and powerful biomarker for predicting clinical outcomes in NPC. Our nomograms based on LA and EBV DNA can predict individual prognosis more accurately and effectively.

Impact of sex on treatment-related adverse effects and prognosis in nasopharyngeal carcinoma.

BACKGROUND: In nasopharyngeal cancer (NPC), women have a lower incidence and mortality rate than men. Whether sex influences the prognosis of NPC patients remains debatable. We retrospectively examined the influence of sex on treatment-related side effects and prognosis in NPC. METHODS: Clinical data of 1,462 patients with NPC treated at the Southern Hospital of Southern Medical University from January 2004 to December 2015 were retrospectively examined. Statistical analysis was performed to assess differences in overall survival (OS), distant metastasis-free survival (DMFS), local recurrence-free survival(LRFS), and progression-free survival(PFS), as well as treatment-related adverse effects, including myelosuppression, gastrointestinal responses, and radiation pharyngitis and dermatitis, between men and women. RESULTS: Women had better 5-year OS (81.5% vs. 87.1%, P = 0.032) and DMFS (76.2% vs. 83.9%, P = 0.004) than men. Analysis by age showed that the prognoses of premenopausal and menopausal women were better than those of men, whereas prognoses of postmenopausal women and men were not significantly different. Additionally, women had a better prognosis when stratified by treatment regimen. Furthermore, chemotherapy-related adverse effects were more severe in women than in men; however, the incidences of radiation laryngitis and dermatitis were not significantly different between the sexes. Logistic regression analysis revealed that the female sex was an independent risk factor for severe myelosuppression and gastrointestinal reactions. CONCLUSIONS: Chemotherapy-related side effects are more severe but the overall prognosis is better in women with NPC than in men with NPC. Patients may benefit from a personalized treatment approach for NPC. TRIAL REGISTRATION: This study was approved by the Medical Ethics Committee of Nanfang Hospital of the Southern Medical University (NFEC-201,710-K3).

Potential of dental pulp stem cells and their products in promoting peripheral nerve regeneration and their future applications.

Peripheral nerve injury (PNI) seriously affects people's quality of life. Stem cell therapy is considered a promising new option for the clinical treatment of PNI. Dental stem cells, particularly dental pulp stem cells (DPSCs), are adult pluripotent stem cells derived from the neuroectoderm. DPSCs have significant potential in the field of neural tissue engineering due to their numerous advantages, such as easy isolation, multidifferentiation potential, low immunogenicity, and low transplant rejection rate. DPSCs are extensively used in tissue engineering and regenerative medicine, including for the treatment of sciatic nerve injury, facial nerve injury, spinal cord injury, and other neurodegenerative diseases. This article reviews research related to DPSCs and their advantages in treating PNI, aiming to summarize the therapeutic potential of DPSCs for PNI and the underlying mechanisms and providing valuable guidance and a foundation for future research.

Benefit of Nasal Douche in COVID-19 Patients with Recurrence of Positive SARS-CoV-2 Viral RNA.

Purpose: The purpose was to review relevant clinical data and formulate recommendations supporting the use of saline as a simple rinse for an early reassuring intervention to reduce the occurrence of re-positive COVID-19 patients. Methods: We conducted a single-centre retrospective cohort study, which enrolled patients with confirmed re-testing positive COVID-19 during 7-60 days after discharge from Third People's Hospital of Shenzhen. By one-to-two propensity score matching for age and sex, the control group of those not re-testing positive during the same period served as matched control. Results: A total of 223 patients were included in our study, 94 in re-positive group and 129 in non-re-positive group. The result shows that the rates of nasal douche treatment in the non-re-positive group were considerably higher than that of the re-positive group. And the Ct value of nasal douche group increased faster than that of non-nasal douche group after the Ct value reaching ≥35. Further analysis revealed that the higher the Ct value at the time of readmission, the shorter the time of average Ct values to reach ≥35. Conclusion: These findings suggest that nasal douche is beneficial to shorten the time of virus nucleic acid turning negative, thereby reducing the incidence of re-positive. The prevention and control of epidemics focuses on re-positive patients with Ct values <35.

Developing Effective Cancer Vaccines Using Rendered-Inactive Tumor Cells.

Cancer is a major public health threat, and researchers are constantly looking for new ways to develop effective treatments. One approach is the use of cancer vaccines, which work by boosting the body's immune system to fight cancer. The goal of this study was to develop an effective cancer vaccine using rendered-inactive tumor cells. A CMS5 fibrosarcoma tumor model in BALB/c mice and an E.G7 lymphoma tumor model in C57BL/6 mice were used to evaluate how mitomycin C-inactivated tumor cells mediated tumor protection. The results showed that immunization with inactivated CMS5 cells significantly improved tumor suppression after a challenge with live CMS5 tumor cells, but no effect was observed using the E.G7 tumor model. The results suggested that DC (dendritic cell) responses to tumor antigens are critical. The maturation and activation of DCs were effectively promoted by mitomycin C-treated CMS5 cells, as well as enhanced phagocytosis ability in vitro. The tumor-protective effects established by the vaccination of inactivated CMS5 cells were CD8+ T cell-dependent, as the antitumor responses disappeared after eliminating CD8+ T cells. It was found that the tumor-prevention efficacy was dramatically increased by combining inactivated CM55 tumor cells with anti-CD25 antibodies to temporarily deplete Treg cells (regulatory T cells). This strategy could also significantly induce the rejection against E.G7 tumors. In addition, vaccination with anti-CD25 antibodies plus inactivated CMS5 cells elicited antitumor responses against heterologous tumors. According to the findings of this study, combining the immunization of inactivated tumor cells with an anti-CD25 antibody may be an effective method for cancer prevention.

Transient regulatory-T-cell interruption promotes skin-resident memory T cells mediated tumor protection.

Most cancer immunotherapy approaches aim to stimulate cytotoxic CD8+ T lymphocytes to reject tumor cells. Due to the tumor-mediated suppressive micro-environment, of which the major contributor is regulatory T cells (Tregs), promising preclinical approaches were disappointing in clinical settings. Our recent study demonstrated that transient interruption of Tregs could induce CD8+ T cell responses to reject tumors in an animal model. The long-term tumor protective effect has yet not to be investigated. In this study, mice with Treg depletion rejected tumors and were rechallenged to study anti-tumor memory immune responses. The effects of major immune cell subsets on tumor protection were explored. Finally, we demonstrate that transient depletion of Tregs during primary tumor challenge can result in long-lasting protection against the tumor rechallenge. Skin-resident memory T cells (sTRM) were major factors in rejecting rechallenged tumors even when peripheral T cells were deficient. These findings highlight a promising strategy for empowering tissue-resident memory T cells for cancer prevention and immunotherapy in humans by interrupting Tregs.

mTORC2 acts as a gatekeeper for mTORC1 deficiency-mediated impairments in ILC3 development.

Group 3 innate lymphoid cells (ILC3s) are mediators of intestinal immunity and barrier function. Recent studies have investigated the role of the mammalian target of rapamycin complex (mTOR) in ILC3s, whereas the mTORC1-related mechanisms and crosstalk between mTORC1 and mTORC2 involved in regulating ILC3 homeostasis remain unknown. In this study, we found that mTORC1 but not mTORC2 was critical in ILC3 development, IL-22 production, and ILC3-mediated intestinal homeostasis. Single-cell RNA sequencing revealed that mTORC1 deficiency led to disruption of ILC3 heterogeneity, showing an increase in differentiation into ILC1-like phenotypes. Mechanistically, mTORC1 deficiency decreased the expression of NFIL3, which is a critical transcription factor responsible for ILC3 development. The activities of both mTORC1 and mTORC2 were increased in wild-type ILC3s after activation by IL-23, whereas inhibition of mTORC1 by Raptor deletion or rapamycin treatment resulted in increased mTORC2 activity. Previous studies have demonstrated that S6K, the main downstream target of mTORC1, can directly phosphorylate Rictor to dampen mTORC2 activity. Our data found that inhibition of mTORC1 activity by rapamycin reduced Rictor phosphorylation in ILC3s. Reversing the increased mTORC2 activity via heterozygous or homozygous knockout of Rictor in Raptor-deleted ILC3s resulted in severe ILC3 loss and complete susceptibility to intestinal infection in mice with mTORC1 deficiency (100% mortality). Thus, mTORC1 acts as a rheostat of ILC3 heterogeneity, and mTORC2 protects ILC3s from severe loss of cells and immune activity against intestinal infection when mTORC1 activity is diminished.