Control of visceral leishmaniasis (VL) depends on pro-inflammatory Th1 cells that activate infected tissue macrophages to kill resident intracellular parasites. However, pro-inflammatory cytokines produced by Th1 cells can damage tissues, and require tight regulation. Th1 cell IL-10 production is an important cell-autologous mechanism to prevent such damage. However, IL-10-producing Th1 (type I regulatory; Tr1) cells can also delay control of parasites and the generation of immunity following drug treatment or vaccination. To identify molecules to target to alter the balance between Th1 and Tr1 cells for improved anti-parasitic immunity, we compared the molecular and phenotypic profiles of Th1 and Tr1 cells in experimental VL caused by Leishmania donovani infection of C57BL/6 mice. We also identified a shared Tr1 cell protozoan signature by comparing the transcriptional profiles of Tr1 cells from mice with experimental VL and malaria. We identified LAG3 as an important co-inhibitory receptor in VL patients and experimental VL, and reveal tissue-specific heterogeneity of co-inhibitory receptor expression by Tr1 cells. We also discovered a role for the transcription factor Pbx1 in suppressing CD4+ T cell cytokine production. This work provides insights into the development and function of CD4+ T cells during protozoan parasitic infections and identifies key immunoregulatory molecules.
Chelsea L. Edwards, Jessica A. Engel, Fabian De Labastida Rivera, Susanna S. Ng, Dillon Corvino, Marcela Montes de Oca, Teija C.M. Frame, Shashi Bhushan Chauhan, Siddharth Sanker Singh, Awnish Kumar, Yulin Wang, Jinrui Na, Pamela Mukhopadhyay, Jason S. Lee, Susanne Nylén, Shyam Sundar, Rajiv Kumar, Christian R. Engwerda
Hair loss is a debilitating condition associated with the depletion of dermal papilla cells (DPCs), which can be replenished by dermal sheath cells (DSCs). Hence, strategies aimed at increasing the population of DPCs and DSCs hold great promise for the treatment of hair loss. In this study, we demonstrated that introducing exogenous DPCs and DSCs (hair follicle mesenchymal stem cells) could effectively migrate and integrate into the dermal papilla and dermal sheath niches, leading to enhanced hair growth and prolonged anagen phases. However, the homing rates of DPCs and DSCs were influenced by various factors, including recipient mouse depilation, cell passage number, cell dose, and immune rejection. Through in vitro and in vivo experiments, we further discovered that the CXCL13/CXCR5 pathway mediated the homing of DPCs and DSCs into hair follicle niches. This study underscores the potential of cell-based therapies for hair loss by targeted delivery of DPCs and DSCs to their respective niches, and sheds light on the intriguing concept that isolated mesenchymal stem cells can home back to their original niche microenvironment.
Kaitao Li, Fang Liu, Ye He, Qian Qu, Pingping Sun, Lijuan Du, Jin Wang, Ruosi Chen, Yuyang Gan, Danlan Fu, Zhexiang Fan, Bingcheng Liu, Zhiqi Hu, Yong Miao
Osteoclasts specialize in bone resorption and are critical for bone remodeling. Previous studies have shown that osteoclasts possess abundant mitochondria and derive most energy through oxidative phosphorylation (OXPHOS). However, the energy substrates fueling OXPHOS in osteoclasts remain to be fully defined. Here, we showed that osteoclast differentiation was coupled with increased oxidation of glucose, glutamine and oleate. Transcriptomic analyses with RNA sequencing revealed marked upregulation of genes participating in OXPHOS and mitochondrial fatty acids oxidation, during osteoclast differentiation. Increased mitochondrial oxidation of long-chain fatty acids was required for osteoclast differentiation in vitro. However, blocking fatty acid oxidation in vivo, by deletion of Cpt1a in osteoclast progenitors, impaired osteoclast formation only in the female mice. The Cpt1a-deficient females were further protected from osteoclast activation by a high fat diet. The males, on the contrary, exhibited normal bone resorption despite Cpt1a deletion, regardless of the dietary fat content. Moreover, concurrent deletion of Mpc1 and Cpt1a, blocking mitochondrial oxidation of both glucose and fatty acids in the osteoclast lineage, failed to impede bone resorption in the males. The study therefore uncovers a female-specific dependence on mitochondrial oxidation of fatty acids and glucose in osteoclasts in vivo.
Chao Song, Arianna Valeri, Fangfang Song, Xing Ji, Xueyang Liao, Tyler Marmo, Rebecca A. Seeley, Jared Rutter, Fanxin Long
Nipah virus (NiV), a bat-borne paramyxovirus, results in neurological and respiratory diseases with high mortality in humans and animals. Developing vaccines is crucial against the diseases. Previous few studies focused on fusion (F) protein alone as the immunogen. Numerous NiV strains have been identified, including two representative strains from Malaysia (NiV-M) and Bangladesh (NiV-B), which differ significantly from the other. In this study, an F protein sequence with the potential to prevent different NiV strain infections was designed by bioinformatics analysis after an in-depth study of NiV sequences in GenBank. Then, a chimpanzee adenovirus vector vaccine and a DNA vaccine were developed. High levels of immune responses were detected by AdC68-F, pVAX1-F and a prime-boost strategy (pVAX1-F/AdC68-F) in mice. After high titers of humoral responses were induced, the hamsters were challenged by the lethal NiV-M and NiV-B strains, respectively. It was reassuring that the vaccinated hamsters did not show any clinical signs and survived 21 days after infection with either strain of NiV, and no virus was detected in different tissues either. These results indicated that vaccines provided complete protection against representative strains of NiV infection and had the potential to be developed as a broad-spectrum vaccine for human use.
Mingqing Lu, Yanfeng Yao, Hang Liu, Xuekai Zhang, Xuejie Li, Yuanhua Liu, Yun Peng, Tong Chen, Yun Sun, Ge Gao, Miaoyu Chen, Jiaxuan Zhao, XiaoYu Zhang, Chunhong Yin, Weiwei Guo, Peipei Yang, Xue Hu, Juhong Rao, Entao Li, Gary Wong, Zhiming Yuan, Sandra Chiu, Chao Shan, Jiaming Lan
The management of preretinal fibrovascular membranes, a devastating complication of advanced diabetic retinopathy (DR), remains challenging. We characterized the molecular profile of cell populations in these fibrovascular membranes to identify new therapeutic targets. Preretinal fibrovascular membranes were surgically removed from patients and submitted for single cell RNA (scRNA) sequencing. Differential gene expression was implemented to define the transcriptomic profile of these cells and revealed the presence of endothelial, inflammatory, and stromal cells. Endothelial cell re-clustering identified subclusters characterized by non-canonical trascriptomic profile, and active angiogenesis. Deeper investigation of the inflammatory cells showed a subcluster of macrophages expressing pro-angiogenic cytokines, presumably contributing to angiogenesis. The stromal cell cluster included a pericyte-myofibroblast transdifferentiating subcluster, indicating the involvement of pericytes in fibrogenesis. Differentially expressed gene analysis showed that Adipocyte Enhancer-binding Protein 1, AEBP1, was significantly upregulated in myofibroblast clusters, suggesting that this molecule may have a potential role in transformation. Cell culture experiments with human retinal pericytes (HRP) in high glucose condition confirmed the molecular transformation of pericytes towards myofibroblastic lineage. siAEBP1 transfection in HRP reduced the expression of profibrotic markers in high glucose. In conclusion, AEBP1 signaling modulates pericyte-myofibroblast transformation, suggesting that targeting AEBP1 could prevent scar tissue formation in advanced DR.
Katia Corano-Scheri, Jeremy A. Lavine, Thomas R. Tedeschi, Benjamin R. Thomson, Amani A. Fawzi
Monocyte-derived macrophages, the major source of pathogenic macrophages in COVID-19, are oppositely instructed by M-CSF or GM-CSF, which promote the generation of anti-inflammatory/immunosuppressive MAFB+ (M-MØ) or pro-inflammatory macrophages (GM-MØ), respectively. The transcriptional profile of prevailing macrophage subsets in severe COVID-19 led us to hypothesize that MAFB shapes the transcriptome of pulmonary macrophages driving severe COVID-19 pathogenesis. We have now assessed the role of MAFB in the response of monocyte-derived macrophages to SARS-CoV-2 through genetic and pharmacological approaches, and demonstrated that MAFB regulates the expression of the genes that define pulmonary pathogenic macrophages in severe COVID-19. Indeed, SARS-CoV-2 potentiates the expression of MAFB and MAFB-regulated genes in M-MØ and GM-MØ, where MAFB upregulates the expression of pro-fibrotic and neutrophil-attracting factors. Thus, MAFB determines the transcriptome and functions of the monocyte-derived macrophage subsets that underlie pulmonary pathogenesis in severe COVID-19 and controls the expression of potentially useful biomarkers for COVID-19 severity.
Miriam Simón-Fuentes, Israel Ríos, Cristina Herrero, Fátima Lasala, Nuria Labiod, Joanna Luczkowiak, Emilia Roy-Vallejo, Sara Fernández de Córdoba-Oñate, Pablo Delgado-Wicke, Matilde Bustos, Elena Fernández-Ruiz, Maria Colmenares, Amaya Puig-Kröger, Rafael Delgado, Miguel A. Vega, Angel L. Corbi, Angeles Domínguez-Soto
Although tyrosine kinase inhibitor (TKI) therapy shows marked clinical efficacy in patients with anaplastic lymphoma kinase (ALK) and ROS proto-oncogene 1 (ROS1)-positive non-small cell lung cancer (NSCLC), most of these patients eventually relapse with acquired resistance. Therefore, genome-wide CRISPR-Cas9 knockout screening was performed using an ALK-positive NSCLC cell line established from pleural effusion without ALK-TKI treatment. After 9 days of ALK-TKI therapy, sequencing analysis was performed, which identified several tumor-suppressor genes, such as NF2 or MED12, and multiple new candidate genes. Among them this study focused on ERRFI1, which is known as MIG6 and negatively regulates EGFR signaling. Interestingly MIG6 loss induced the resistance to ALK-TKIs by treatment with quite a low dose of EGF, which is equivalent to plasma concentration through the upregulation of MAPK and PI3K/Akt/mTOR pathways. Combination therapy with ALK-TKIs and anti-EGFR antibodies could overcome the acquired resistance in both in vivo and in vitro models. In addition, this confirmed that MIG6 loss induces resistance to ROS1-TKIs in ROS1-positive cell lines. This study found a novel factor that plays a role in ALK and ROS1-TKI resistance by activating the EGFR pathway with low-dose ligands.
Nobuyuki Kondo, Takahiro Utsumi, Yuki Shimizu, Ai Takemoto, Tomoko Oh-hara, Ken Uchibori, Sophia Subat-Motoshi, Hironori Ninomiya, Kengo Takeuchi, Makoto Nishio, Yasunari Miyazaki, Ryohei Katayama
Patients with Down syndrome (DS, trisomy 21, T21) are at increased risk of transient abnormal myelopoiesis (TAM) and acute megakaryoblastic leukemia (ML-DS). Both TAM and ML-DS require prenatal somatic mutations in GATA1, resulting in the truncated isoform GATA1s. The mechanism by which individual chromosome 21 (HSA21) genes synergize with GATA1s for leukemic transformation is challenging to study, in part due to limited human cell models with wild type GATA1 or GATA1s. HSA21-encoded DYRK1A is overexpressed in ML-DS and may be a therapeutic target. To determine how DYRK1A influences hematopoiesis in concert with GATA1s, we used gene editing to disrupt all 3 alleles of DYRK1A in isogenic T21 induced pluripotent stem cells (iPSCs) with and without the GATA1s mutation. Unexpectedly, hematopoietic differentiation revealed that DYRK1A loss combined with GATA1s leads to increased megakaryocyte proliferation and decreased maturation. This proliferative phenotype was associated with upregulation of D-type cyclins and hyperphosphorylation of Rb to allow E2F release and de-repression of its downstream targets. Notably, DYRK1A loss had no effect in T21/wtGATA1 megakaryocytes. These surprising results suggest that DYRK1A and GATA1 may synergistically restrain megakaryocyte proliferation in Trisomy 21 and that DYRK1A inhibition may not be a therapeutic option for GATA1s-associated leukemias.
Ying Ting Sit, Kaoru Takasaki, Hyun Hyung An, Yan Xiao, Christian Hurtz, Peter Gearhart, Zhe Zhang, Paul Gadue, Deborah French, Stella T. Chou
Aberrant angiogenesis in hepatocellular carcinoma (HCC) is associated with tumor growth, progression, and local or distant metastasis. Hypoxia-inducible factor 1α (HIF-1α) is a transcription factor that plays a major role in regulating angiogenesis during adaptation of tumor cells to nutrient-deprived microenvironment. Genetic defects in Krebs cycle enzymes, such as succinate dehydrogenase and fumarate hydratase, result in elevation of oncometabolites succinate and fumarate, thereby increasing HIF-1α stability and activating the HIF-1α signaling pathway. However, whether other metabolites regulate HIF-1α stability remains unclear. Here, we reported that the enzyme in phenylalanine/tyrosine catabolism glutathione S-transferase zeta 1 (GSTZ1) deficiency led to accumulation of succinylacetone, which was structurally similar to α-ketoglutarate. Succinylacetone competed with α-ketoglutarate for PHD2 binding and inhibited PHD2 activity, preventing hydroxylation of HIF-1α, thus resulting in its stabilization and consequent expression of vascular endothelial growth factor (VEGF). Our findings suggest that GSTZ1 may serve as an important tumor suppressor owing to its ability to inhibit the HIF-1α/VEGFA axis in HCC. Moreover, we explored the therapeutic potential of HIF-1α inhibitor combined with anti-PD-L1 therapy to effectively prevent HCC angiogenesis and tumorigenesis in Gstz1-knockout mice, suggesting a potentially actionable strategy for HCC treatment.
Huating Luo, Qiujie Wang, Fan Yang, Rui Liu, Qingzhu Gao, Bin Cheng, Xue Lin, Luyi Huang, Chang Chen, Jin Xiang, Kai Wang, Bo Qin, Ni Tang
Diabetes commonly affects cancer patients. We investigated the influence of diabetes on breast cancer biology using a three-pronged approach that included analysis of orthotopic human tumor xenografts, patient tumors, and breast cancer cells exposed to diabetes/hyperglycemia-like conditions. We aimed to identify shared phenotypes and molecular signatures by investigating the metabolome, transcriptome, and tumor mutational burden. Diabetes and hyperglycemia did not enhance cell proliferation but induced mesenchymal and stem cell-like phenotypes linked to increased mobility and odds of metastasis. They also promoted oxyradical formation and both a transcriptome and mutational signatures of DNA repair deficiency. Moreover, food- and microbiome-derived metabolites tended to accumulate in breast tumors in the presence of diabetes, potentially affecting tumor biology. Breast cancer cells cultured under hyperglycemia-like conditions acquired increased DNA damage and sensitivity to DNA repair inhibitors. Based on these observations, we conclude that diabetes-associated breast tumors may show an increased drug response to DNA damage repair inhibitors.
Gatikrushna Panigrahi, Julián Candia, Tiffany H. Dorsey, Wei Tang, Yuuki Ohara, Jung S. Byun, Tsion Z. Minas, Amy L. Zhang, Anuoluwapo Ajao, Ashley Cellini, Harris G. Yfantis, Amy L. Flis, Dean Mann, Olga Ioffe, Xin Wei Wang, Huaitian Liu, Christopher A. Loffredo, Anna Maria Napoles, Stefan Ambs
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