Hoeft, K;Schaefer, GJL;Kim, H;Schumacher, D;Bleckwehl, T;Long, Q;Klinkhammer, BM;Peisker, F;Koch, L;Nagai, J;Halder, M;Ziegler, S;Liehn, E;Kuppe, C;Kranz, J;Menzel, S;Costa, I;Wahida, A;Boor, P;Schneider, RK;Hayat, S;Kramann, R;
PMID: 36807143 | DOI: 10.1016/j.celrep.2023.112131
Fibrosis represents the common end stage of chronic organ injury independent of the initial insult, destroying tissue architecture and driving organ failure. Here we discover a population of profibrotic macrophages marked by expression of Spp1, Fn1, and Arg1 (termed Spp1 macrophages), which expands after organ injury. Using an unbiased approach, we identify the chemokine (C-X-C motif) ligand 4 (CXCL4) to be among the top upregulated genes during profibrotic Spp1 macrophage differentiation. In vitro and in vivo studies show that loss of Cxcl4 abrogates profibrotic Spp1 macrophage differentiation and ameliorates fibrosis after both heart and kidney injury. Moreover, we find that platelets, the most abundant source of CXCL4 in vivo, drive profibrotic Spp1 macrophage differentiation. Single nuclear RNA sequencing with ligand-receptor interaction analysis reveals that macrophages orchestrate fibroblast activation via Spp1, Fn1, and Sema3 crosstalk. Finally, we confirm that Spp1 macrophages expand in both human chronic kidney disease and heart failure.
Cell Rep. 2018 Oct 16;25(3):585-597.e7.
Joost S, Jacob T, Sun X, Annusver K, La Manno G, Sur I, Kasper M.
PMID: 30332640 | DOI: 10.1016/j.celrep.2018.09.059
Epithelial tissues, such as the skin, rely on cellular plasticity of stem cells (SCs) from different niches to restore tissue function after injury. How these molecularly and functionally diverse SC populations respond to injury remains elusive. Here, we genetically labeled Lgr5- or Lgr6-expressing cells from the hair follicle bulge and interfollicular epidermis (IFE), respectively, and monitored their individual transcriptional adaptations during wound healing using single-cell transcriptomics. Both Lgr5 and Lgr6 progeny rapidly induced a genetic wound signature that, for Lgr5 progeny, included the remodeling of receptors to permit interactions with the wound environment, a property that Lgr6 progeny possessed even before wounding. When contributing to re-epithelialization, Lgr5 progeny gradually replaced their bulge identity with an IFE identity, and this process started already before Lgr5 progeny left the bulge. Altogether, this study reveals how different SCs respond and adapt to a new environment, potentially explaining cellular plasticity of many epithelial tissues.
Lim, RG;Al-Dalahmah, O;Wu, J;Gold, MP;Reidling, JC;Tang, G;Adam, M;Dansu, DK;Park, HJ;Casaccia, P;Miramontes, R;Reyes-Ortiz, AM;Lau, A;Hickman, RA;Khan, F;Paryani, F;Tang, A;Ofori, K;Miyoshi, E;Michael, N;McClure, N;Flowers, XE;Vonsattel, JP;Davidson, S;Menon, V;Swarup, V;Fraenkel, E;Goldman, JE;Thompson, LM;
PMID: 36543778 | DOI: 10.1038/s41467-022-35388-x
The complexity of affected brain regions and cell types is a challenge for Huntington's disease (HD) treatment. Here we use single nucleus RNA sequencing to investigate molecular pathology in the cortex and striatum from R6/2 mice and human HD post-mortem tissue. We identify cell type-specific and -agnostic signatures suggesting oligodendrocytes (OLs) and oligodendrocyte precursors (OPCs) are arrested in intermediate maturation states. OL-lineage regulators OLIG1 and OLIG2 are negatively correlated with CAG length in human OPCs, and ATACseq analysis of HD mouse NeuN-negative cells shows decreased accessibility regulated by OL maturation genes. The data implicates glucose and lipid metabolism in abnormal cell maturation and identify PRKCE and Thiamine Pyrophosphokinase 1 (TPK1) as central genes. Thiamine/biotin treatment of R6/1 HD mice to compensate for TPK1 dysregulation restores OL maturation and rescues neuronal pathology. Our insights into HD OL pathology spans multiple brain regions and link OL maturation deficits to abnormal thiamine metabolism.
Matson, KJE;Russ, DE;Kathe, C;Hua, I;Maric, D;Ding, Y;Krynitsky, J;Pursley, R;Sathyamurthy, A;Squair, JW;Levi, BP;Courtine, G;Levine, AJ;
PMID: 36163250 | DOI: 10.1038/s41467-022-33184-1
After spinal cord injury, tissue distal to the lesion contains undamaged cells that could support or augment recovery. Targeting these cells requires a clearer understanding of their injury responses and capacity for repair. Here, we use single nucleus RNA sequencing to profile how each cell type in the lumbar spinal cord changes after a thoracic injury in mice. We present an atlas of these dynamic responses across dozens of cell types in the acute, subacute, and chronically injured spinal cord. Using this resource, we find rare spinal neurons that express a signature of regeneration in response to injury, including a major population that represent spinocerebellar projection neurons. We characterize these cells anatomically and observed axonal sparing, outgrowth, and remodeling in the spinal cord and cerebellum. Together, this work provides a key resource for studying cellular responses to injury and uncovers the spontaneous plasticity of spinocerebellar neurons, uncovering a potential candidate for targeted therapy.
Keenan, BP;McCarthy, EE;Ilano, A;Yang, H;Zhang, L;Allaire, K;Fan, Z;Li, T;Lee, DS;Sun, Y;Cheung, A;Luong, D;Chang, H;Chen, B;Marquez, J;Sheldon, B;Kelley, RK;Ye, CJ;Fong, L;
PMID: 36130508 | DOI: 10.1016/j.celrep.2022.111384
Suppressive myeloid cells can contribute to immunotherapy resistance, but their role in response to checkpoint inhibition (CPI) in anti-PD-1 refractory cancers, such as biliary tract cancer (BTC), remains elusive. We use multiplexed single-cell transcriptomic and epitope sequencing to profile greater than 200,000 peripheral blood mononuclear cells from advanced BTC patients (n = 9) and matched healthy donors (n = 8). Following anti-PD-1 treatment, CD14+ monocytes expressing high levels of immunosuppressive cytokines and chemotactic molecules (CD14CTX) increase in the circulation of patients with BTC tumors that are CPI resistant. CD14CTX can directly suppress CD4+ T cells and induce SOCS3 expression in CD4+ T cells, rendering them functionally unresponsive. The CD14CTX gene signature associates with worse survival in patients with BTC as well as in other anti-PD-1 refractory cancers. These results demonstrate that monocytes arising after anti-PD-1 treatment can induce T cell paralysis as a distinct mode of tumor-mediated immunosuppression leading to CPI resistance.
Disease models & mechanisms
Paese, CLB;Chang, CF;Kristeková, D;Brugmann, SA;
PMID: 35818799 | DOI: 10.1242/dmm.049611
Ciliopathies represent a disease class characterized by a broad range of phenotypes including polycystic kidneys and skeletal anomalies. Ciliopathic skeletal phenotypes are among the most common and most difficult to treat due to a poor understanding of the pathological mechanisms leading to disease. Using an avian model (talpid2) for a human ciliopathy with both kidney and skeletal anomalies (Orofaciodigital syndrome 14), we identified disruptions in the FGF23-PTH axis that resulted in reduced calcium uptake in the developing mandible and subsequent micrognathia. While pharmacological intervention with the FDA-approved pan-FGFR inhibitor AZD4547 alone rescued expression of the FGF target Sprouty2, it did not significantly rescue micrognathia. In contrast, treatment with a cocktail of AZD4547 and Teriparatide acetate, a PTH agonist and FDA-approved treatment for osteoporosis, resulted in a molecular, cellular, and phenotypic rescue of ciliopathic micrognathia in talpid2 mutants. Together, these data provide novel insight into pathological molecular mechanisms associated with ciliopathic skeletal phenotypes and a potential therapeutic strategy for a pleiotropic disease class with limited to no treatment options.
Tansley, S;Uttam, S;Ureña Guzmán, A;Yaqubi, M;Pacis, A;Parisien, M;Deamond, H;Wong, C;Rabau, O;Brown, N;Haglund, L;Ouellet, J;Santaguida, C;Ribeiro-da-Silva, A;Tahmasebi, S;Prager-Khoutorsky, M;Ragoussis, J;Zhang, J;Salter, MW;Diatchenko, L;Healy, LM;Mogil, JS;Khoutorsky, A;
PMID: 35149686 | DOI: 10.1038/s41467-022-28473-8
Activation of microglia in the spinal cord following peripheral nerve injury is critical for the development of long-lasting pain hypersensitivity. However, it remains unclear whether distinct microglia subpopulations or states contribute to different stages of pain development and maintenance. Using single-cell RNA-sequencing, we show that peripheral nerve injury induces the generation of a male-specific inflammatory microglia subtype, and demonstrate increased proliferation of microglia in male as compared to female mice. We also show time- and sex-specific transcriptional changes in different microglial subpopulations following peripheral nerve injury. Apolipoprotein E (Apoe) is the top upregulated gene in spinal cord microglia at chronic time points after peripheral nerve injury in mice. Furthermore, polymorphisms in the APOE gene in humans are associated with chronic pain. Single-cell RNA sequencing analysis of human spinal cord microglia reveals a subpopulation with a disease-related transcriptional signature. Our data provide a detailed analysis of transcriptional states of mouse and human spinal cord microglia, and identify a link between ApoE and chronic pain in humans.
Wang, X;Ramos, R;Phan, AQ;Yamaga, K;Flesher, JL;Jiang, S;Oh, JW;Jin, S;Jahid, S;Kuan, CH;Nguyen, TK;Liang, HY;Shettigar, NU;Hou, R;Tran, KH;Nguyen, A;Vu, KN;Phung, JL;Ingal, JP;Levitt, KM;Cao, X;Liu, Y;Deng, Z;Taguchi, N;Scarfone, VM;Wang, G;Paolilli, KN;Wang, X;Guerrero-Juarez, CF;Davis, RT;Greenberg, EN;Ruiz-Vega, R;Vasudeva, P;Murad, R;Widyastuti, LHP;Lee, HL;McElwee, KJ;Gadeau, AP;Lawson, DA;Andersen, B;Mortazavi, A;Yu, Z;Nie, Q;Kunisada, T;Karin, M;Tuckermann, J;Esko, JD;Ganesan, AK;Li, J;Plikus, MV;
PMID: 37344645 | DOI: 10.1038/s41586-023-06172-8
Niche signals maintain stem cells in a prolonged quiescence or transiently activate them for proper regeneration1. Altering balanced niche signalling can lead to regenerative disorders. Melanocytic skin nevi in human often display excessive hair growth, suggesting hair stem cell hyperactivity. Here, using genetic mouse models of nevi2,3, we show that dermal clusters of senescent melanocytes drive epithelial hair stem cells to exit quiescence and change their transcriptome and composition, potently enhancing hair renewal. Nevus melanocytes activate a distinct secretome, enriched for signalling factors. Osteopontin, the leading nevus signalling factor, is both necessary and sufficient to induce hair growth. Injection of osteopontin or its genetic overexpression is sufficient to induce robust hair growth in mice, whereas germline and conditional deletions of either osteopontin or CD44, its cognate receptor on epithelial hair cells, rescue enhanced hair growth induced by dermal nevus melanocytes. Osteopontin is overexpressed in human hairy nevi, and it stimulates new growth of human hair follicles. Although broad accumulation of senescent cells, such as upon ageing or genotoxic stress, is detrimental for the regenerative capacity of tissue4, we show that signalling by senescent cell clusters can potently enhance the activity of adjacent intact stem cells and stimulate tissue renewal. This finding identifies senescent cells and their secretome as an attractive therapeutic target in regenerative disorders.
Am J Respir Crit Care Med. 2018 Dec 15.
Reyfman PA, Walter JM, Joshi N, Anekalla KR, McQuattie-Pimentel AC, Chiu S, Fernandez R, Akbarpour M, Chen CI, Ren Z, Verma R, Abdala-Valencia H, Nam K, Chi M, Han S, Gonzalez-Gonzalez FJ, Soberanes S, Watanabe S, Williams KJN, Flozak AS, Nicholson TT, Morgan VK, Winter DR, Hinchcliff M, Hrusch CL, Guzy RD, Bonham CA, Sperling AI, Bag R, Hamanaka RB, Mutlu GM, Yeldandi AV, Marshall SA, Shilatifard A, Amaral LAN, Perlman H, Sznajder JI, Argento AC, Gillespie CT, Dematte J, Jain M, Singer BD, Ridge KM, Lam AP, Bharat A, Bhorade SM, Gottardi CJ, Budinger GRS, Misharin AV.
PMID: 30554520 | DOI: 10.1164/rccm.201712-2410OC
Abstract RATIONALE: The contributions of diverse cell populations in the human lung to pulmonary fibrosis pathogenesis are poorly understood. Single-cell RNA sequencing can reveal changes within individual cell populations during pulmonary fibrosis that are important for disease pathogenesis. OBJECTIVES: To determine whether single-cell RNA sequencing can reveal disease-related heterogeneity within alveolar macrophages, epithelial cells or other cell types in lung tissue from subjects with pulmonary fibrosis compared with controls. METHODS: We performed single-cell RNA sequencing on lung tissue obtained from eight transplant donors and eight recipients with pulmonary fibrosis and on one bronchoscopic cryobiospy sample from a patient with idiopathic pulmonary fibrosis. We validated these data in using in situ RNA hybridization, immunohistochemistry, and bulk RNA-sequencing on flow-sorted cells from 22 additional subjects. MEASUREMENTS AND MAIN RESULTS: We identified a distinct, novel population of profibrotic alveolar macrophages exclusively in patients with fibrosis. Within epithelial cells, the expression of genes involved in Wnt secretion and response was restricted to non-overlapping cells. We identified rare cell populations including airway stem cells and senescent cells emerging during pulmonary fibrosis. We developed a web-based tool to explore these data. CONCLUSIONS: We generated a single cell atlas of pulmonary fibrosis. Using this atlas we demonstrated heterogeneity within alveolar macrophages and epithelial cells from subjects with pulmonary fibrosis. These results support the feasibility of discovery-based approaches using next generation sequencing technologies to identify signaling pathways for targeting in the development of personalized therapies for patients with pulmonary fibrosis.
