Regulatory Cells Research Articles

The m5C/m6A/m7G-related non-apoptotic regulatory cell death genes for the prediction of the prognosis and immune infiltration status in hepatocellular carcinoma.

5-methylcytosine/N6-methyladenosine/N7-methylguanosine (m5C/m6A/m7G)-related genes play a critical role in tumor occurrence and progression, and non-apoptotic regulatory cell death (NARCD) is closely linked to tumor development and immunity. However, the role of m5C/m6A/m7G-related NARCD genes in hepatocellular carcinoma (HCC) remains unclear. We used m5C/m6A/m7G-related NARCD genes to construct a prognostic model of HCC for prognostic prediction and clinical treatment of patients. We obtained transcriptome data for HCC from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC). Using the least absolute shrinkage and selection operator (LASSO) regression, we identified m5C/m6A/m7G-related NARCD genes and constructed a prognostic model through multivariate Cox regression. Model performance was assessed using Kaplan-Meier and receiver operating characteristic (ROC) curves, with external validation using the ICGC. Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses were used to study differentially expressed genes between high- and low-risk groups. We also examined immune cell infiltration, drug response, and cell communication between tumor cells and immune cells in high-risk groups. We identified 140 m5C/m6A/m7G-related NARCD genes, using five of them to build the prognostic model. Functional enrichment analysis revealed enrichment in tumor and immune-related pathways for risk genes. The high-risk group displayed increased immune cell infiltration and better responses to immune checkpoint inhibitors (ICIs). High-risk patients were more responsive to cisplatin, doxorubicin, and mitomycin C, while low-risk patients were more sensitive to erlotinib. Cell communication analysis indicated that high-risk tumor cells used insulin-like growth factor (IGF) and macrophage migration inhibitory factor (MIF) signaling pathways to send signals to immune cells and received signals through the bone morphogenetic protein (BMP) and lymphotoxin-related inducible ligand (LIGHT) pathways. We have developed a prognostic model with m5C/m6A/m7G-related NARCD genes to predict the prognosis of HCC patients. This model can offer insights into the effectiveness of immunotherapy and chemotherapy for HCC patients.

Gasdermin D Mediated Mitochondrial Metabolism Orchestrate Neurogenesis Through LDHA During Embryonic Development.

Regulatory cell death is an important way to eliminate the DNA damage that accompanies the rapid proliferation of neural stem cells during cortical development, including pyroptosis, apoptosis, and so on. Here, the study reports that the absence of GSDMD-mediated pyroptosis results in defective DNA damage sensor pathways accompanied by aberrant neurogenesis and autism-like behaviors in adult mice. Furthermore, GSDMD is involved in organizing the mitochondrial electron transport chain by regulating the AMPK/PGC-1α pathway to target Aifm3. This process promotes a switch from oxidative phosphorylation to glycolysis. The perturbation of metabolic homeostasis in neural progenitor cells increases lactate production which acts as a signaling molecule to regulate the p38MAPK pathway. And activates NF-𝜿B transcription to disrupt cortex development. This abnormal proliferation of neural progenitor cells can be rescued by inhibiting glycolysis and lactate production. Taken together, the study proposes a metabolic axis regulated by GSDMD that links pyroptosis with metabolic reprogramming. It provides a flexible perspective for the treatment of neurological disorders caused by genotoxic stress and neurodevelopmental disorders such as autism.

Oral tolerance to dietary antigens and Foxp3+ regulatory T cells.

Immune tolerance to foods develops in the intestine upon food ingestion and is essential to prevent IgE-mediated food allergy and gut inflammation. In homeostasis, the intestine is a tolerogenic environment that favors the formation of food-specific Foxp3+ regulatory T cells. A tolerogenic intestinal environment depends on colonization by diverse microbiota and exposure to solid foods at a critical period in early life. These early immune responses lead to the induction of antigen-specific Foxp3+ regulatory T cells in draining mesenteric lymph nodes. These peripherally induced regulatory cells circulate and seed the lamina propria of the gut, exerting suppressive function systemically and locally in the intestine. Successful establishment of a tolerogenic intestinal environment in early life sets the stage for oral tolerance to new antigens in adult life.

265.5: T regulatory cell phenotypes in renal transplant patients with long surviving graft, increased Th2-like Treg and reduced Th1- and Th17-like Treg.

265.5: T regulatory cell phenotypes in renal transplant patients with long surviving graft, increased Th2-like Treg and reduced Th1- and Th17-like Treg.

Allogenic Vertebral Body Adherent Mesenchymal Stromal Cells Promote Muscle Recovery in Diabetic Mouse Model of Limb Ischemia

Chronic limb threatening ischemia (CLTI) carries a significant risk for amputation especially in diabetic patients with poor options for revascularization. Phase I trials have demonstrated efficacy of allogeneic mesenchymal stromal cells (MSC) in treating diabetic CLTI. Vertebral bone adherent mesenchymal stromal cells (vBA-MSC) are derived from vertebral bodies of deceased organ donors which offer the distinct advantage of providing a 1,000x greater yield compared to that of living donor bone aspiration. This study describes the effects of intramuscular injection of allogenic vBA-MSC in promoting limb perfusion and muscle recovery in a diabetic CLTI mouse model. A CLTI mouse model was created through unilateral ligation of the femoral artery in male polygenic diabetic TALLYHO mice. Treated mice were injected with vBA-MSC into the gracilis muscle of the ischemic limb 7 days post ligation. Gastrocnemius or tibialis muscle was assessed post-mortem for fibrosis by collagen staining, capillary density via immunohistochemistry, and mRNA by quantitative real time PCR. Laser Doppler perfusion imaging and plantar flexion muscle testing were performed to quantify changes in limb perfusion and muscle function. Compared to vehicle control, treated mice demonstrated indicators of muscle recovery including decreased fibrosis, increased perfusion, muscle torque, and angiogenesis. PCR analysis of muscle obtained 7- and 30-days post vBA-MSC injection showed an upregulation in expression of MyoD1 (p = 0.03) and MyH3 (p = 0.008) mRNA representing muscle regeneration, VEGF-A (p = 0.002 ; p = 0.004) signifying angiogenesis as well as IL-10 (p < 0.001), T regulatory cell marker Foxp3 (p = 0.04), and M2-biased macrophage marker Mrc1 (CD206) (p = 0.02). These findings indicate human allogeneic vBA-MSC ameliorate ischemic muscle damage and rescue muscle function. These results in a murine model will enable further studies to develop potential therapies for diabetic CLTI patients.

Activating mutations remodel the chromatin accessibility landscape to drive distinct regulatory networks in KMT2A-rearranged acute leukemia.

Activating FLT3 and RAS mutations commonly occur in leukemia with KMT2A-gene rearrangements (KMT2A-r). However, how these mutations cooperate with the KMT2A-r to remodel the epigenetic landscape is unknown. Using a retroviral acute myeloid leukemia (AML) mouse model driven by KMT2A::MLLT3, we show that FLT3 ITD , FLT3 N676K , and NRAS G12D remodeled the chromatin accessibility landscape and associated transcriptional networks. Although the activating mutations shared a common core of chromatin changes, each mutation exhibits unique profiles with most opened peaks associating with enhancers in intronic or intergenic regions. Specifically, FLT3 N676K and NRAS G12D rewired similar chromatin and transcriptional networks, distinct from those mediated by FLT3 ITD . Motif analysis uncovered a role for the AP-1 family of transcription factors in KMT2A::MLLT3 leukemia with FLT3 N676K and NRAS G12D , whereas Runx1 and Stat5a/Stat5b were active in the presence of FLT3 ITD . Furthermore, transcriptional programs linked to immune cell regulation were activated in KMT2A-r AML expressing NRAS G12D or FLT3 N676K , and the expression of NKG2D-ligands on KMT2A-r cells rendered them sensitive to CAR T cell-mediated killing. Human KMT2A-r AML cells could be pharmacologically sensitized to NKG2D-CAR T cells by treatment with the histone deacetylase inhibitor LBH589 (panobinostat) which caused upregulation of NKG2D-ligand levels. Co-treatment with LBH589 and NKG2D-CAR T cells enabled robust AML cell killing, and the strongest effect was observed for cells expressing NRAS G12D . Finally, the results were validated and extended to acute leukemia in infancy. Combined, activating mutations induced mutation-specific changes in the epigenetic landscape, leading to changes in transcriptional programs orchestrated by specific transcription factor networks.

Profiling of collagen and extracellular matrix deposition from cell culture using in vitro ExtraCellular matrix mass spectrometry imaging (ivECM-MSI)

While numerous approaches have been reported towards understanding single cell regulation, there is limited understanding of single cell production of extracellular matrix phenotypes. Collagens are major proteins of the extracellular microenvironment extensively used in basic cell culture, tissue engineering, and biomedical applications. However, identifying compositional regulation of collagen remains challenging. Here, we report the development of In vitro ExtraCellular Matrix Mass Spectrometry Imaging (ivECM-MSI) as a tool to rapidly and simultaneously define collagen subtypes from coatings and basic cell culture applications. The tool uses the mass spectrometry imaging platform with reference libraries to produce visual and numerical data types. The method is highly integrated with basic in vitro strategies as it may be used with conventional cell chambers on minimal numbers of cells and with minimal changes to biological experiments. Applications tested include semi-quantitation of collagen composition in culture coatings, time course collagen deposition, deposition altered by gene knockout, and changes induced by drug treatment. This approach provides new access to proteomic information on how cell types respond to and change the extracellular microenvironment and provides a holistic understanding of both the cell and extracellular response.

ScRNA-seq revealing the molecular atlas of the goat follicular microenvironment over the time course of ovulation

Ovulation is paramount for female animal fertility, necessitating a thorough understanding of its process and molecular underpinnings. This study aimed to delineate the goat ovary temporal dynamics of ovulation. Utilizing single-cell sequencing, we analyzed follicular fluid samples obtained at 0, 6, 12, 18, and 24 h post-hCG administration, identifying 4 cell types and 6 myeloid cell subtypes. We elucidated gene expression and functional changes in granulosa cells over the time course of ovulation. Notably, our study detected and confirmed immune cell infiltration at 6 h post-LH peak. Additionally, we observed significant cellular interactions between granulosa cells and macrophages, with granulosa cells expressing IL1RAP, COL4A1, COL4A2 implicated in immune cell regulation, while macrophages expressed EREG to facilitate oocyte maturation. Collectively, our investigation has established a comprehensive single-cell transcriptome atlas of the ovulating goat ovary for advancing exploration into ovulation mechanisms and developing therapies for ovulatory disorders.

Exploring the prognosis value, immune correlation, and drug responsiveness prediction of homeobox C6 (HOXC6) in lung adenocarcinoma

BackgroundsHomeobox C6 (HOXC6) is a gene that encodes for a transcription factor involved in various cellular processes, including development and differentiation, and regulates cancer progression. However, the carcinogenesis and effect of HOXC6 in lung adenocarcinoma (LUAD) still need further investigation.MethodsThe differential HOXC6 expression levels at the mRNA and protein level were explored in multiple public datasets, including The Cancer Genome Atlas (TCGA) and Human Protein Atlas (HPA) dataset. Gene Expression Omnibus (GSE31210), International Cancer Genome Consortium (ICGC) datasets and the LUAD sample from Affiliated Hospital of Guangxi Medical University. We also investigated the relation between HOXC6 expression and clinicopathologic indexes. Furthermore, the correlation of immune infiltration, drug responsiveness and HOXC6 were explored.ResultsThe upregulated HOXC6 expressions at mRNA and protein levels were found in LUAD tissues compared to the normal lung tissues. Besides, the relatively shorter overall survival time, worse T and N stages, and lower immune scores were found in the high-expression HOXC6 subgroup. Notably, T cells regulatory (Tregs), Macrophages M0, and Plasma cells had the higher infiltration levels in the high-HOXC6 expression subgroup, while NK cells activated, Monocytes, Dendritic cells resting, and Mast cells resting had the lower infiltration levels. In drug sensitivity analysis, we revealed that LUAD patients with high-HOXC6 expression may be more susceptible to Camptothecin, Cytarabine, Docetaxel, Elesclomol, Rapamycin, Sorafinib, Temsirolimus, and Vorinostat.ConclusionsTaken together, there is a great potential for HOXC6 to become a prognosis biomarker and contribute to develop treatment strategies for LUAD patients. Further mechanism exploration and drug development for HOXC6 are needed.

The Major Role of T Regulatory Cells in the Efficiency of Vaccination in General and Immunocompromised Populations: A Review.

Since their conception with the smallpox vaccine, vaccines used worldwide have mitigated multiple pandemics, including the recent COVID-19 outbreak. Insightful studies have uncovered the complexities of different functional networks of CD4 T cells (T helper 1 (Th1); Th2, Th17) and CD8 T cells (T cytotoxic; Tc), as well as B cell (BIgM, BIgG, BIgA and BIgE) subsets, during the response to vaccination. Both T and B cell subsets form central, peripheral, and tissue-resident subsets during vaccination. It has also become apparent that each vaccination forms a network of T regulatory subsets, namely CD4+ CD25+ Foxp3+ T regulatory (Treg) cells and interleukin-10 (IL-10)-producing CD4+ Foxp3- T regulatory 1 (Tr1), as well as many others, which shape the quality/quantity of vaccine-specific IgM, IgG, and IgA antibody production. These components are especially critical for immunocompromised patients, such as older individuals and allograft recipients, as their vaccination may be ineffective or less effective. This review focuses on considering how the pre- and post-vaccination Treg/Tr1 levels influence the vaccination efficacy. Experimental and clinical work has revealed that Treg/Tr1 involvement evokes different immune mechanisms in diminishing vaccine-induced cellular/humoral responses. Alternative steps may be considered to improve the vaccination response, such as increasing the dose, changing the delivery route, and/or repeated booster doses of vaccines. Vaccination may be combined with anti-CD25 (IL-2Rα chain) or anti-programmed cell death protein 1 (PD-1) monoclonal antibodies (mAb) to decrease the Tregs and boost the T/B cell immune response. All of these data and strategies for immunizations are presented and discussed, aiming to improve the efficacy of vaccination in humans and especially in immunocompromised and older individuals, as well as organ transplant patients.

Bone Marrow Mesenchymal Stem Cell-Derived Exosomes Alleviate Nuclear Pulposus Cells Degeneration Through the miR-145a-5p/USP31/HIF-1α Signaling Pathway.

Bone marrow mesenchymal stem cell (BMSC)-derived exosomes possess therapeutic potential against degenerative diseases. This study aimed to investigate the effects of BMSC-derived exosomes on intervertebral disc degeneration (IVDD) and explore the underlying molecular mechanisms. Through transcriptome sequencing and histological analysis, we observed a significant increase in HIF-1α expression in degenerative nucleus pulposus (NP) tissues. The addition of HIF-1α resulted in elevated expression of inflammatory factors IL-1β and IL-6, higher levels of matrix-degrading enzyme MMP13, and lower expression of aggrecan in NP cells. Co-culturing with BMSCs diminished the expression of HIF-1α, MMP13, IL-1β, and IL-6 in degenerative NP cells induced by overload pressure. miRNA chip analysis and PCR validation revealed that miR-145a-5p was the primary miRNA carried by BMSC-derived exosomes. Overexpression of miR-145a-5p was effective in minimizing the expression of HIF-1α, MMP13, IL-1β, and IL-6 in degenerative NP cells. Luciferase reporter assays confirmed USP31 as the target gene of miR-145a-5p, and the regulation of NP cells by BMSC-derived exosomes via miR-145a-5p was dependent on USP31. In conclusion, BMSC-derived exosomes alleviated IVDD through the miR-145a-5p/USP31/HIF-1α signaling pathway, providing valuable insights into the treatment of IVDD.

Cytokinin and ALOG proteins regulate pluripotent stem cell identity in the moss Physcomitrium patens.

The shoot apical meristem (SAM) contains pluripotent stem cells that produce all the aerial parts of the plant. Stem cells undergo asymmetric cell divisions to self-renew and to produce differentiating cells. Our research focused on unraveling the mechanisms governing the specification of these two distinct cell fates following the stem cell division. For this purpose, we used the model organism Physcomitrium patens, which features a singular pluripotent stem cell known as the gametophore apical cell. We show that the activity of cytokinins, critical stem cell regulators, is restricted to the gametophore apical cell due to the specific localization of PpLOG, the enzyme responsible for cytokinin activation. In turn, PpTAW, which promotes differentiating cell identity of the merophyte, is excluded from the gametophore apical cell by the action of cytokinins. We propose a cytokinin-based model for the establishment of asymmetry in the pluripotent stem cell division.

Surface Immune Checkpoints as Potential Biomarkers in Physiological Pregnancy and Recurrent Pregnancy Loss.

Due to the genetic diversity between the mother and the fetus, heightened control over the immune system during pregnancy is crucial. Immunological parameters determined by clinicians in women with idiopathic recurrent spontaneous abortion (RSA) include the quantity and activity of Natural Killer (NK) and Natural Killer T (NKT) cells, the quantity of regulatory T lymphocytes, and the ratio of pro-inflammatory cytokines, which indicate imbalances in Th1 and Th2 cell response. The processes are controlled by immune checkpoint proteins (ICPs) expressed on the surface of immune cells. We aim to investigate differences in the expression of ICPs on T cells, T regulatory lymphocytes, NK cells, and NKT cells in peripheral blood samples collected from RSA women, pregnant women, and healthy multiparous women. We aim to discover new insights into the role of ICPs involved in recurrent pregnancy loss. Peripheral blood mononuclear cells (PBMCs) were isolated by gradient centrifugation from blood samples obtained from 10 multiparous women, 20 pregnant women (11-14th week of pregnancy), and 20 RSA women, at maximum of 72 h after miscarriage. The PBMCs were stained for flow cytometry analysis. Standard flow cytometry immunophenotyping of PBMCs was performed using antibodies against classical lymphocyte markers, including CD3, CD4, CD8, CD56, CD25, and CD127. Additionally, ICPs were investigated using antibodies against Programmed Death Protein-1 (PD-1, CD279), T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3, CD366), V-domain Ig suppressor of T cell activation (VISTA), T cell immunoglobulin and ITIM domain (TIGIT), and Lymphocyte activation gene 3 (LAG-3). We observed differences in the surface expression of ICPs in the analyzed subpopulations of lymphocytes between early pregnancy and RSA, after miscarriage, and in women. We noted diminished expression of PD-1 on T lymphocytes (p = 0.0046), T helper cells (CD3CD4 positive cells, p = 0.0165), T cytotoxic cells (CD3CD8 positive cells, p = 0.0046), T regulatory lymphocytes (CD3CD4CD25CD127 low positive cells, p = 0.0106), and NKT cells (CD3CD56/CD16 positive cells, p = 0.0438), as well as LAG-3 on lymphocytes T (p = 0.0225) T helper, p = 0.0426), T cytotoxic cells (p = 0.0458) and Treg (p = 0.0293), and cells from RSA women. Impaired expression of TIM-3 (p = 0.0226) and VISTA (p = 0.0039) on CD8 cytotoxic T and NK (TIM3 p = 0.0482; VISTA p = 0.0118) cells was shown, with an accompanying increased expression of TIGIT (p = 0.0211) on NKT cells. The changes in the expression of surface immune checkpoints indicate their involvement in the regulation of pregnancy. The data might be utilized to develop specific therapies for RSA women based on the modulation of ICP expression.

Pterostilbene improves neurological dysfunction and neuroinflammation after ischaemic stroke via HDAC3/Nrf1-mediated microglial activation

BackgroundStroke is a type of acute brain damage that can lead to a series of serious public health challenges. Demonstrating the molecular mechanism of stroke-related neural cell degeneration could help identify a more efficient treatment for stroke patients. Further elucidation of factors that regulate microglia and nuclear factor (erythroid-derived 2)-like 1 (Nrf1) may lead to a promising strategy for treating neuroinflammation after ischaemic stroke. In this study, we investigated the possible role of pterostilbene (PTS) in Nrf1 regulation in cell and animal models of ischaemia stroke.MethodsWe administered PTS, ITSA1 (an HDAC activator) and RGFP966 (a selective HDAC3 inhibitor) in a mouse model of middle cerebral artery occlusion–reperfusion (MCAO/R) and a model of microglial oxygen‒glucose deprivation/reperfusion (OGD/R). The brain infarct size, neuroinflammation and microglial availability were also determined. Dual-luciferase reporter, Nrf1 protein stability and co-immunoprecipitation assays were conducted to analyse histone deacetylase 3 (HDAC3)/Nrf1-regulated Nrf1 in an OGD/R-induced microglial injury model.ResultsWe found that PTS decreased HDAC3 expression and activity, increased Nrf1 acetylation in the cell nucleus and inhibited the interaction of Nrf1 with p65 and p65 accumulation, which reduced infarct volume and neuroinflammation (iNOS/Arg1, TNF-α and IL-1β levels) after ischaemic stroke. Furthermore, the CSF1R inhibitor PLX5622 induced elimination of microglia and attenuated the therapeutic effect of PTS following MCAO/R. In the OGD/R model, PTS relieved OGD/R-induced microglial injury and TNF-α and IL-1β release, which were dependent on Nrf1 acetylation through the upregulation of HDAC3/Nrf1 signalling in microglia. However, the K105R or/and K139R mutants of Nrf1 counteracted the impact of PTS in the OGD/R-induced microglial injury model, which indicates that PTS treatment might be a promising strategy for ischaemia stroke therapy.ConclusionThe HDAC3/Nrf1 pathway regulates the stability and function of Nrf1 in microglial activation and neuroinflammation, which may depend on the acetylation of the lysine 105 and 139 residues in Nrf1. This mechanism was first identified as a potential regulatory mechanism of PTS-based neuroprotection in our research, which may provide new insight into further translational applications of natural products such as PTS.

LncRNA MALAT-1 modulates EGFR-TKI resistance in lung adenocarcinoma cells by downregulating miR-125

Molecular targeted therapy resistance remains a major challenge in treating lung adenocarcinoma (LUAD). The resistance of Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs, epidermal growth factor receptor-tyrosine kinase inhibitor) plays a dominant role in molecular targeted therapy. Our previous research demonstrated the role of MALAT-1 (Metastasis-associated lung adenocarcinoma transcript 1) in the formation of Erlotinib-resistant LUAD cells. This study aims to uncover the mechanism of MALAT-1 overexpression in Erlotinib-resistant LUAD cells. The RT2 LncRNA PCR array system was used to explore MALAT-1 regulation in Erlotinib-resistant LUAD cells through patient serum analysis. Dual luciferase reporter experiments confirmed the binding between MALAT-1 and miR-125, leading to regulation of miR-125 expression. Functional assays were performed to elucidate the impact of MALAT1 on modulating drug resistance, growth, and Epithelial-mesenchymal transition (EMT, Epithelial-mesenchymal transition) in both parental and Erlotinib-resistant LUAD cells. The investigation unveiled the mechanism underlying the competing endogenous RNA (ceRNA, competing endogenouse RNA) pathway. MALAT1 exerted its regulatory effect on miR-125 as a competing endogenous RNA (ceRNA). Moreover, MALAT1 played a role in modulating the sensitivity of LUAD cells to Erlotinib. Rab25 was identified as the direct target of miR-125 and mediated the functional effects of MALAT1 in Erlotinib-resistant LUAD cells. In conclusion, our study reveals overexpress MALAT-1 cause the drug resistance of EGFR-TKIs in non-small cell lung cancer (NSCLC) through the MALAT-1/miR-125/Rab25 axis. These findings present a potential novel therapeutic target and perspective for the treatment of LUAD.

Structural basis of frizzled 7 activation and allosteric regulation

Frizzleds (ten paralogs: FZD1-10) belong to the class F of G protein-coupled receptors (GPCRs), which remains poorly understood despite its crucial role in multiple key biological functions including embryonic development, stem cell regulation, and homeostasis in the adult. FZD7, one of the most studied members of the family, is more specifically involved in the migration of mesendoderm cells during the development and renewal of intestinal stem cells in adults. Moreover, FZD7 has been highlighted for its involvement in tumor development predominantly in the gastrointestinal tract. This study reports the structure of inactive FZD7, without any stabilizing mutations, determined by cryo-electron microscopy (cryo-EM) at 1.9 Å resolution. We characterize a fluctuating water pocket in the core of the receptor important for FZD7 dynamics. Molecular dynamics simulations are used to investigate the temporal distribution of those water molecules and their importance for potential conformational changes in FZD7. Moreover, we identify lipids interacting with the receptor core and a conserved cholesterol-binding site, which displays a key role in FZD7 association with a transducer protein, Disheveled (DVL), and initiation of downstream signaling and signalosome formation.

Whole transcriptome sequencing revealed the gene regulatory network of hypoxic response in yak Sertoli cells

Yaks live in the Qinghai-Tibet Plateau for a long time where oxygen is scarce, but can ensure the smooth development of testis and spermatogenesis. The key lies in the functional regulation of the Sertoli cells under hypoxia. In this study, we sequenced yak Sertoli cells cultured in normal oxygen concentration (Normoxia) and treated with low oxygen concentration (Hypoxia) by whole transcriptomics, and screened out 194 differentially expressed mRNAs (DEmRNAs), 934 differentially expressed LncRNAs (DELncRNAs) and 129 differentially expressed miRNAs (DEmiRNAs). GO and KEGG analysis showed that these differential genes were mainly concentrated in PI3K-AKT, MAPK, RAS, and other signaling pathways, and were associated with glucose metabolism, tight junction, steroid hormone synthesis, cell fusion, and immunity of yak Sertoli cells. We constructed the gene interaction network of yak Sertoli cells in hypoxia and screened out the relationship pairs related to glucose metabolism and tight junction. The results suggested that the changes in energy metabolism, tight junction, and immune regulation of yak Sertoli cells under hypoxia might provide favorable conditions for spermatogenesis. This study provides data for further study on the role of non-coding RNA in testis development and spermatogenesis of yak.

Evaluation of Th1/Th2/Th17 Balance in Pulmonary Cystic Echinococcosis Patients.

Cystic echinococcosis (CE) is a neglected tropical disease prevalent worldwide, particularly in rural areas. Previous studies evaluated immune responses in patients with hepatic CE, however none had assessed Th1, Th2 and Th17 levels simultaneously in pulmonary CE patients. This study aimed to fill this gap in literature by using flow cytometry analysis. Peripheral blood mononuclear cells (PBMCs) were isolated from blood samples collected from healthy control (HC) volunteers and patients with active pulmonary CE cysts. The PBMCs were analysed to evaluate Th1, Th2, and Th17 cell levels within the CD3 + CD4 + T-cell population, using antibodies against interferon (IFN)-γ, interleukin (IL)-4, and IL-17, respectively. Our analysis revealed elevated Th2 levels in CE patients, while Th1 and Th17 cell counts showed no significant difference between HC volunteers and patients with pulmonary CE. The results indicate an imbalanced Th1/Th2/Th17 cell regulation in the pathogenesis of pulmonary CE. Future studies are recommended to compare immune responses between pulmonary and hepatic CE to confirm these findings and evaluate any potential difference in the immunopathology associated with the two clinical forms of CE.

Drp1 splice variants regulate ovarian cancer mitochondrial dynamics and tumor progression

Aberrant mitochondrial fission/fusion dynamics are frequently associated with pathologies, including cancer. We show that alternative splice variants of the fission protein Drp1 (DNM1L) contribute to the complexity of mitochondrial fission/fusion regulation in tumor cells. High tumor expression of the Drp1 alternative splice variant lacking exon 16 relative to other transcripts is associated with poor outcome in ovarian cancer patients. Lack of exon 16 results in Drp1 localization to microtubules and decreased association with mitochondrial fission sites, culminating in fused mitochondrial networks, enhanced respiration, changes in metabolism, and enhanced pro-tumorigenic phenotypes in vitro and in vivo. These effects are inhibited by siRNAs designed to specifically target the endogenously expressed transcript lacking exon 16. Moreover, lack of exon 16 abrogates mitochondrial fission in response to pro-apoptotic stimuli and leads to decreased sensitivity to chemotherapeutics. These data emphasize the pathophysiological importance of Drp1 alternative splicing, highlight the divergent functions and consequences of changing the relative expression of Drp1 splice variants in tumor cells, and strongly warrant consideration of alternative splicing in future studies focused on Drp1.

H3.3K122A results in a neomorphic phenotype in mouse embryonic stem cells.

The histone variant H3.3 acts in coordination with histone posttranslational modifications and other chromatin features to facilitate appropriate transcription. Canonical histone H3 and histone variant H3.3 are post-translationally modified with the genomic distribution of these marks denoting different features and with more recent evidence suggesting that these modifications may influence transcription. While the majority of posttranslational modifications occur on histone tails, there are defined modifications within the globular domain, such as acetylation of H3K122/H3.3K122. To understand the function of the residue H3.3K122 in transcriptional regulation, we attempted to generate H3.3K122A mouse embryonic stem (mES) cells but were unsuccessful. Through multi-omic profiling of mutant cell lines harboring two or three of four H3.3 targeted alleles, we have uncovered that H3.3K122A is neomorphic and results in lethality. This is surprising as prior studies demonstrate H3.3-null mES cells are viable and pluripotent, albeit with reduced differentiation capacity. Together, these studies have uncovered a novel dependence of a globular domain residue of H3.3 for viability and broadened our understanding of how histone variants contribute to transcription regulation and pluripotency in mES cells.