Kathiriya, JJ;Wang, C;Zhou, M;Brumwell, A;Cassandras, M;Le Saux, CJ;Cohen, M;Alysandratos, KD;Wang, B;Wolters, P;Matthay, M;Kotton, DN;Chapman, HA;Peng, T;
PMID: 34969962 | DOI: 10.1038/s41556-021-00809-4
Loss of alveolar type 2 cells (AEC2s) and the ectopic appearance of basal cells in the alveoli characterize severe lung injuries such as idiopathic pulmonary fibrosis (IPF). Here we demonstrate that human alveolar type 2 cells (hAEC2s), unlike murine AEC2s, transdifferentiate into basal cells in response to fibrotic signalling in the lung mesenchyme, in vitro and in vivo. Single-cell analysis of normal hAEC2s and mesenchymal cells in organoid co-cultures revealed the emergence of pathologic fibroblasts and basaloid cells previously described in IPF. Transforming growth factor-β1 and anti-bone morphogenic protein signalling in the organoids promoted transdifferentiation. Trajectory and histologic analyses of both hAEC2-derived organoids and IPF epithelium indicated that hAEC2s transdifferentiate into basal cells through alveolar-basal intermediates that accumulate in proximity to pathologic CTHRC1hi/TGFB1hi fibroblasts. Our study indicates that hAEC2 loss and expansion of alveolar metaplastic basal cells in severe human lung injuries are causally connected through an hAEC2-basal cell lineage trajectory driven by aberrant mesenchyme.
Hou, S;Li, Z;Dong, J;Gao, Y;Chang, Z;Ding, X;Li, S;Li, Y;Zeng, Y;Xin, Q;Wang, B;Ni, Y;Ning, X;Hu, Y;Fan, X;Hou, Y;Li, X;Wen, L;Zhou, B;Liu, B;Tang, F;Lan, Y;
PMID: 35079138 | DOI: 10.1038/s41422-022-00615-z
Arteriogenesis rather than unspecialized capillary expansion is critical for restoring effective circulation to compromised tissues in patients. Deciphering the origin and specification of arterial endothelial cells during embryonic development will shed light on the understanding of adult arteriogenesis. However, during early embryonic angiogenesis, the process of endothelial diversification and molecular events underlying arteriovenous fate settling remain largely unresolved in mammals. Here, we constructed the single-cell transcriptomic landscape of vascular endothelial cells (VECs) during the time window for the occurrence of key vasculogenic and angiogenic events in both mouse and human embryos. We uncovered two distinct arterial VEC types, the major artery VECs and arterial plexus VECs, and unexpectedly divergent arteriovenous characteristics among VECs that are located in morphologically undistinguishable vascular plexus intra-embryonically. Using computational prediction and further lineage tracing of venous-featured VECs with a newly developed Nr2f2CrexER mouse model and a dual recombinase-mediated intersectional genetic approach, we revealed early and widespread arterialization from the capillaries with considerable venous characteristics. Altogether, our findings provide unprecedented and comprehensive details of endothelial heterogeneity and lineage relationships at early angiogenesis stages, and establish a new model regarding the arteriogenesis behaviors of early intra-embryonic vasculatures.
McCaffrey, EF;Donato, M;Keren, L;Chen, Z;Delmastro, A;Fitzpatrick, MB;Gupta, S;Greenwald, NF;Baranski, A;Graf, W;Kumar, R;Bosse, M;Fullaway, CC;Ramdial, PK;Forgó, E;Jojic, V;Van Valen, D;Mehra, S;Khader, SA;Bendall, SC;van de Rijn, M;Kalman, D;Kaushal, D;Hunter, RL;Banaei, N;Steyn, AJC;Khatri, P;Angelo, M;
PMID: 35058616 | DOI: 10.1038/s41590-021-01121-x
Tuberculosis (TB) in humans is characterized by formation of immune-rich granulomas in infected tissues, the architecture and composition of which are thought to affect disease outcome. However, our understanding of the spatial relationships that control human granulomas is limited. Here, we used multiplexed ion beam imaging by time of flight (MIBI-TOF) to image 37 proteins in tissues from patients with active TB. We constructed a comprehensive atlas that maps 19 cell subsets across 8 spatial microenvironments. This atlas shows an IFN-γ-depleted microenvironment enriched for TGF-β, regulatory T cells and IDO1+ PD-L1+ myeloid cells. In a further transcriptomic meta-analysis of peripheral blood from patients with TB, immunoregulatory trends mirror those identified by granuloma imaging. Notably, PD-L1 expression is associated with progression to active TB and treatment response. These data indicate that in TB granulomas, there are local spatially coordinated immunoregulatory programs with systemic manifestations that define active TB.
Buchanan, KL;Rupprecht, LE;Kaelberer, MM;Sahasrabudhe, A;Klein, ME;Villalobos, JA;Liu, WW;Yang, A;Gelman, J;Park, S;Anikeeva, P;Bohórquez, DV;
PMID: 35027761 | DOI: 10.1038/s41593-021-00982-7
Guided by gut sensory cues, humans and animals prefer nutritive sugars over non-caloric sweeteners, but how the gut steers such preferences remains unknown. In the intestine, neuropod cells synapse with vagal neurons to convey sugar stimuli to the brain within seconds. Here, we found that cholecystokinin (CCK)-labeled duodenal neuropod cells differentiate and transduce luminal stimuli from sweeteners and sugars to the vagus nerve using sweet taste receptors and sodium glucose transporters. The two stimulus types elicited distinct neural pathways: while sweetener stimulated purinergic neurotransmission, sugar stimulated glutamatergic neurotransmission. To probe the contribution of these cells to behavior, we developed optogenetics for the gut lumen by engineering a flexible fiberoptic. We showed that preference for sugar over sweetener in mice depends on neuropod cell glutamatergic signaling. By swiftly discerning the precise identity of nutrient stimuli, gut neuropod cells serve as the entry point to guide nutritive choices.
Liu, JJ;Tsien, RW;Pang, ZP;
PMID: 34980924 | DOI: 10.1038/s41593-021-00984-5
Hypothalamic melanin-concentrating hormone (MCH) polypeptide contributes to regulating energy homeostasis, sleep and memory, although the mechanistic bases of its effects are unknown. In this study, in mice, we uncovered the physiological mechanism underlying the functional role of MCH signaling in projections to the dorsolateral septum (dLS), a region involved in routing hippocampal firing rhythms and encoding spatial memory based on such rhythms. Firing activity within the dLS in response to dorsal CA3 (dCA3) excitation is limited by strong feed-forward inhibition (FFI). We found that MCH synchronizes dLS neuronal firing with its dCA3 inputs by enhancing GABA release, which subsequently reduces the FFI and augments dCA3 excitatory input strength, both via pre-synaptic mechanisms. At the functional level, our data reveal a role for MCH signaling in the dLS in facilitating spatial memory. These findings support a model in which peptidergic signaling within the dLS modulates dorsal hippocampal output and supports memory encoding.
Mascharak, S;Talbott, HE;Januszyk, M;Griffin, M;Chen, K;Davitt, MF;Demeter, J;Henn, D;Bonham, CA;Foster, DS;Mooney, N;Cheng, R;Jackson, PK;Wan, DC;Gurtner, GC;Longaker, MT;
PMID: 35077667 | DOI: 10.1016/j.stem.2021.12.011
Regeneration is the holy grail of tissue repair, but skin injury typically yields fibrotic, non-functional scars. Developing pro-regenerative therapies requires rigorous understanding of the molecular progression from injury to fibrosis or regeneration. Here, we report the divergent molecular events driving skin wound cells toward scarring or regenerative fates. We profile scarring versus YAP-inhibition-induced wound regeneration at the transcriptional (single-cell RNA sequencing), protein (timsTOF proteomics), and tissue (extracellular matrix ultrastructural analysis) levels. Using cell-surface barcoding, we integrate these data to reveal fibrotic and regenerative "molecular trajectories" of healing. We show that disrupting YAP mechanotransduction yields regenerative repair by fibroblasts with activated Trps1 and Wnt signaling. Finally, via in vivo gene knockdown and overexpression in wounds, we identify Trps1 as a key regulatory gene that is necessary and partially sufficient for wound regeneration. Our findings serve as a multi-omic map of wound regeneration and could have therapeutic implications for pathologic fibroses.
Bellomo, G;Rainer, C;Quaranta, V;Astuti, Y;Raymant, M;Boyd, E;Stafferton, R;Campbell, F;Ghaneh, P;Halloran, CM;Hammond, DE;Morton, JP;Palmer, D;Vimalachandran, D;Jones, R;Mielgo, A;Schmid, MC;
PMID: 35022267 | DOI: 10.1136/gutjnl-2021-325272
Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease and cytotoxic chemotherapy is the standard of care treatment for patients with advanced disease. Here, we investigate how the microenvironment in PDAC liver metastases reacts to chemotherapy and its role in metastatic disease progression post-treatment, an area which is poorly understood.The impact of chemotherapy on metastatic disease progression and immune cell infiltrates was characterised using flow and mass cytometry combined with transcriptional and histopathological analysis in experimental PDAC liver metastases mouse models. Findings were validated in patient derived liver metastases and in an autochthonous PDAC mouse model. Human and murine primary cell cocultures and ex vivo patient-derived liver explants were deployed to gain mechanistical insights on whether and how chemotherapy affects the metastatic tumour microenvironment.We show that in vivo, chemotherapy induces an initial infiltration of proinflammatory macrophages into the liver and activates cytotoxic T cells, leading only to a temporary restraining of metastatic disease progression. However, after stopping treatment, neutrophils are recruited to the metastatic liver via CXCL1 and 2 secretion by metastatic tumour cells. These neutrophils express growth arrest specific 6 (Gas6) which leads to AXL receptor activation on tumour cells enabling their regrowth. Disruption of neutrophil infiltration or inhibition of the Gas6/AXL signalling axis in combination with chemotherapy inhibits metastatic growth. Chemotherapy increases Gas6 expression in circulating neutrophils from patients with metastatic pancreatic cancer and recombinant Gas6 is sufficient to promote tumour cell proliferation ex vivo, in patient-derived metastatic liver explants.Combining chemotherapy with Gas6/AXL or neutrophil targeted therapy could provide a therapeutic benefit for patients with metastatic pancreatic cancer.
Annals of the rheumatic diseases
Corbera-Bellalta, M;Alba-Rovira, R;Muralidharan, S;Espígol-Frigolé, G;Ríos-Garcés, R;Marco-Hernández, J;Denuc, A;Kamberovic, F;Pérez-Galán, P;Joseph, A;D'Andrea, A;Bondensgaard, K;Cid, MC;Paolini, JF;
PMID: 35045965 | DOI: 10.1136/annrheumdis-2021-220873
Effective and safe therapies are needed for the treatment of patients with giant cell arteritis (GCA). Emerging as a key cytokine in inflammation, granulocyte-macrophage colony stimulating factor (GM-CSF) may play a role in promoting inflammation in GCA.To investigate expression of GM-CSF and its receptor in arterial lesions from patients with GCA. To analyse activation of GM-CSF receptor-associated signalling pathways and expression of target genes. To evaluate the effects of blocking GM-CSF receptor α with mavrilimumab in ex vivo cultured arteries from patients with GCA.Quantitative real time PCR, in situ RNA hybridisation, immunohistochemistry, immunofluorescence and confocal microscopy, immunoassay, western blot and ex vivo temporal artery culture.GM-CSF and GM-CSF receptor α mRNA and protein were increased in GCA lesions; enhanced JAK2/STAT5A expression/phosphorylation as well as increased expression of target genes CD83 and Spi1/PU.1 were observed. Treatment of ex vivo cultured GCA arteries with mavrilimumab resulted in decreased transcripts of CD3ε, CD20, CD14 and CD16 cell markers, and reduction of infiltrating CD16 and CD3ε cells was observed by immunofluorescence. Mavrilimumab reduced expression of molecules relevant to T cell activation (human leukocyte antigen-DR [HLA-DR]) and Th1 differentiation (interferon-γ), the pro-inflammatory cytokines: interleukin 6 (IL-6), tumour necrosis factor α (TNFα) and IL-1β, as well as molecules related to vascular injury (matrix metalloprotease 9, lipid peroxidation products and inducible nitric oxide synthase [iNOS]). Mavrilimumab reduced CD34 + cells and neoangiogenesis in GCA lesions.The inhibitory effects of mavrilimumab on multiple steps in the GCA pathogenesis cascade in vitro are consistent with the clinical observation of reduced GCA flares in a phase 2 trial and support its development as a therapeutic option for patients with GCA.
Hepatology (Baltimore, Md.)
Khatib, SA;Ma, L;Dang, H;Forgues, M;Chung, JY;Ylaya, K;Hewitt, SM;Chaisaingmongkol, J;Rucchirawat, M;Wang, XW;
PMID: 35034369 | DOI: 10.1002/hep.32345
Hepatocellular carcinoma (HCC) is a highly aggressive and heterogeneous cancer type with limited treatment options. Identifying drivers of tumor heterogeneity may lead to better therapeutic options and favorable patient outcomes. Here, we aimed to investigate whether apoptotic cell death and its spatial architecture is linked to tumor molecular heterogeneity using single-cell in situ hybridization analysis.We analyzed 254 tumor samples from two HCC cohorts using tissue microarrays. We developed a mathematical model to quantify cellular diversity among HCC samples using two tumor markers, CDKN3 and PRC1 as surrogates for heterogeneity and CASP3 as an apoptotic cell death marker. We further explored the impact of potential dying-cell hubs on tumor cell diversity and patient outcome by density contour mapping and spatial proximity analysis. We also developed a selectively controlled in vitro model of cell death using CRISPR/Cas9 to determine therapy response and growth under hypoxic conditions. We found that increasing levels of CASP3+ tumor cells are associated with higher tumor diversity. Interestingly, we discovered regions of densely populated CASP3+ , that we refer to as CASP3+ cell islands, in which the nearby cellular heterogeneity was found to be the greatest compared to cells further away from these islands and that this phenomenon was associated with survival. Additionally, cell culture experiments revealed higher levels of cell death, accompanied by increased CASP3 expression, led to greater therapy resistance and growth under hypoxia.These results are consistent with the hypothesis that increased apoptotic cell death may lead to greater tumor heterogeneity and thus worse patient outcomes.This article is protected by
Yu, H;Miao, W;Ji, E;Huang, S;Jin, S;Zhu, X;Liu, MZ;Sun, YG;Xu, F;Yu, X;
PMID: 35045339 | DOI: 10.1016/j.neuron.2021.12.022
It is well known that affective and pleasant touch promotes individual well-being and facilitates affiliative social communication, although the neural circuit that mediates this process is largely unknown. Here, we show that social-touch-like tactile stimulation (ST) enhances firing of oxytocin neurons in the mouse paraventricular hypothalamus (PVH) and promotes social interactions and positively reinforcing place preference. These results link pleasant somatosensory stimulation to increased social interactions and positive affective valence. We further show that tachykinin 1 (Tac1+) neurons in the lateral and ventrolateral periaqueductal gray (l/vlPAG) send monosynaptic excitatory projections to PVH oxytocin neurons. Functionally, activation of PVH-projecting Tac1+ neurons increases firing of oxytocin neurons, promotes social interactions, and increases preference for the social touch context, whereas reducing activity of Tac1+ neurons abolishes ST-induced oxytocin neuronal firing. Together, these results identify a dipeptidergic pathway from l/vlPAG Tac1+ neurons to PVH oxytocin neurons, through which pleasant sensory experience promotes social behavior.
Joffe, ME;Maksymetz, J;Luschinger, JR;Dogra, S;Ferranti, AS;Luessen, DJ;Gallinger, IM;Xiang, Z;Branthwaite, H;Melugin, PR;Williford, KM;Centanni, SW;Shields, BC;Lindsley, CW;Calipari, ES;Siciliano, CA;Niswender, CM;Tadross, MR;Winder, DG;Conn, PJ;
PMID: 35045338 | DOI: 10.1016/j.neuron.2021.12.027
Inhibitory interneurons orchestrate prefrontal cortex (PFC) activity, but we have a limited understanding of the molecular and experience-dependent mechanisms that regulate synaptic plasticity across PFC microcircuits. We discovered that mGlu5 receptor activation facilitates long-term potentiation at synapses from the basolateral amygdala (BLA) onto somatostatin-expressing interneurons (SST-INs) in mice. This plasticity appeared to be recruited during acute restraint stress, which induced intracellular calcium mobilization within SST-INs and rapidly potentiated postsynaptic strength onto SST-INs. Restraint stress and mGlu5 receptor activation each augmented BLA recruitment of SST-IN phasic feedforward inhibition, shunting information from other excitatory inputs, including the mediodorsal thalamus. Finally, studies using cell-type-specific mGlu5 receptor knockout mice revealed that mGlu5 receptor function in SST-expressing cells is necessary for restraint stress-induced changes to PFC physiology and related behaviors. These findings provide new insights into interneuron-specific synaptic plasticity mechanisms and suggest that SST-IN microcircuits may be promising targets for treating stress-induced psychiatric diseases.
Relizani, K;Echevarría, L;Zarrouki, F;Gastaldi, C;Dambrune, C;Aupy, P;Haeberli, A;Komisarski, M;Tensorer, T;Larcher, T;Svinartchouk, F;Vaillend, C;Garcia, L;Goyenvalle, A;
PMID: 34893881 | DOI: 10.1093/nar/gkab1199
Tricyclo-DNA (tcDNA) is a conformationally constrained oligonucleotide analog that has demonstrated great therapeutic potential as antisense oligonucleotide (ASO) for several diseases. Like most ASOs in clinical development, tcDNA were modified with phosphorothioate (PS) backbone for therapeutic purposes in order to improve their biodistribution by enhancing association with plasma and cell protein. Despite the advantageous protein binding properties, systemic delivery of PS-ASO remains limited and PS modifications can result in dose limiting toxicities in the clinic. Improving extra-hepatic delivery of ASO is highly desirable for the treatment of a variety of diseases including neuromuscular disorders such as Duchenne muscular dystrophy. We hypothesized that conjugation of palmitic acid to tcDNA could facilitate the delivery of the ASO from the bloodstream to the interstitium of the muscle tissues. We demonstrate here that palmitic acid conjugation enhances the potency of tcDNA-ASO in skeletal and cardiac muscles, leading to functional improvement in dystrophic mice with significantly reduced dose of administered ASO. Interestingly, palmitic acid-conjugated tcDNA with a full phosphodiester backbone proved effective with a particularly encouraging safety profile, offering new perspectives for the clinical development of PS-free tcDNA-ASO for neuromuscular diseases.