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Biology subjects

Kalinichenko, V. V.

Publications and source records attributed to Kalinichenko, V. V..

5 recordsLinked to original sources

Isoform-Specific Roles of NTRK2 in Pulmonary Vascular Regeneration

Bronchopulmonary dysplasia (BPD) is a chronic lung disease in premature infants with no curative therapy, characterized by impaired alveologenesis and capillary formation. However, the molecular mechanisms underlying endothelial dysfunction, a key driver of BPD pathogenesis in human, remain poorly understood. Here, through multiomic profiling of vascular endothelial cells isolated from control and BPD patient lungs, we uncovered an expansion of general capillary endothelial cells (gCap) with aberrant expression of the neurotrophic receptor tyrosine kinase 2 (NTRK2) in BPD. Importantly, we identified a pathological NTRK2 isoform switch that dictates the regenerative capacity of gCap cells. Full-length NTRK2 (NTRK2-FL) promoted gCap regeneration in response to hyperoxic injury, whereas RBFOX2-mediated splicing of NTRK2-FL into a truncated isoform (NTRK2-T1) contributed to maladaptive responses and irreversible alveolar simplification in severe BPD cases. Restoring NTRK2-FL using lipid nanoparticle-delivered mRNA promoted angiogenesis and reversed alveolar simplification in vessel organoids and BPD-like mice. These findings identified NTRK2 isoform imbalance as a key driver of endothelial dysfunction and support isoform-specific RNA therapy as a promising strategy for vascular regeneration and repair. HIGHLIGHTS* Multiomic and spatial profiling reveal abnormal gCap subtype in human BPD lungs * NTRK2 isoform switch dictates endothelial regeneration in response to hyperoxic injury * RBFOX2 mediates splicing from NTRK2-FL to NTRK2-T1, driving irreversible alveolar damage * NTRK2-FL mRNA therapy restores vascular regeneration after injury

developmental biology↗

General Capillary Endothelial Cells Undergo Reprogramming into Arterial Endothelial Cells in Pulmonary Hypertension through HIF-2a/Notch4 Pathway

Pulmonary arterial hypertension (PAH) is characterized by a progressive increase of pulmonary vascular resistance and obliterative pulmonary vascular remodeling that result in right heart hypertrophy, failure, and premature death. The underlying mechanisms of loss of distal capillary endothelial cells (ECs) and obliterative vascular lesion formation remain unclear. Our recent single-cell RNA sequencing, spatial transcriptomics analysis, RNASCOPE, and immunostaining analysis showed that arterial ECs accumulation and loss of capillary ECs were evident in human PAH patients and pulmonary hypertension (PH) rodents. Pseudotime trajectory analysis of the single-cell RNA sequencing data suggest that lung capillary ECs transit to arterial ECs during the development of PH. Our study also identified CXCL12 as the marker for arterial ECs in PH. Capillary EC lineage tracing approach using capillary specific-Dre;Tdtomato reporter mice demonstrated that capillary ECs gave rise to arterial ECs during PH development. Genetic deletion of HIF-2a or pharmacological inhibition of Notch4 normalized the arterial programming in PH. In conclusion, our study demonstrates that capillary endothelium transits to arterial endothelium through the HIF-2a-Notch4 pathway during the development of PAH. Thus, targeting arterial EC transition might be a novel approach for treating PAH patients.

physiology↗

Endothelial fatty acid-binding proteins contribute to the pathogenesis of pulmonary hypertension

Pulmonary arterial hypertension (PAH) is a devastating disease characterized by obliterative vascular remodeling and persistent increase of vascular resistance, leading to right heart failure and premature death. Understanding the cellular and molecular mechanisms will help develop novel therapeutic approaches for PAH patients. Single-cell RNA sequencing (scRNAseq) analysis found that both FABP4 and FABP5 were highly induced in endothelial cells (ECs) of Egln1Tie2Cre (CKO) mice, which was also observed in pulmonary arterial ECs (PAECs) from idiopathic PAH (IPAH) patients, and in whole lungs of pulmonary hypertension (PH) rats. Plasma levels of FABP4/5 were upregulated in IPAH patients and directly correlated with severity of hemodynamics and biochemical parameters using plasma proteome analysis. Genetic deletion of both Fabp4 and 5 in CKO mice (Egln1Tie2Cre/Fabp4-5-/-, TKO) caused a reduction of right ventricular systolic pressure (RVSP) and RV hypertrophy, attenuated pulmonary vascular remodeling and prevented the right heart failure assessed by echocardiography, hemodynamic and histological analysis. Employing bulk RNA-seq and scRNA-seq, and spatial transcriptomic analysis, we showed that Fabp4/5 deletion also inhibited EC glycolysis and distal arterial programming, reduced ROS and HIF-2 expression in PH lungs. Thus, PH causes aberrant expression of FABP4/5 in pulmonary ECs which leads to enhanced ECs glycolysis and distal arterial programming, contributing to the accumulation of arterial ECs and vascular remodeling and exacerbating the disease.

molecular biology↗

In Vivo Generation of Bone Marrow from Embryonic Stem Cells in Interspecies Chimeras

Generation of bone marrow (BM) from embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) promises to accelerate the development of future cell therapies for life-threatening disorders. However, such approach is limited by technical challenges to produce a mixture of functional BM progenitor cells able to replace all hematopoietic cell lineages. Herein, we used blastocyst complementation to simultaneously produce all BM hematopoietic cell lineages from mouse ESCs in a rat. Based on FACS analysis and single-cell RNA sequencing, mouse ESCs differentiated into hematopoietic progenitor cells and multiple hematopoietic cell types that were indistinguishable from normal mouse BM cells based on gene expression signatures and cell surface markers. Transplantation of ESC-derived BM cells from mouse-rat chimeras rescued lethally-irradiated syngeneic mice and resulted in long-term contribution of donor cells to hematopoietic cell lineages. Altogether, a fully functional bone marrow was generated from mouse ESCs using rat embryos as "bioreactors". KEY POINTS- We used blastocyst complementation to simultaneously produce all bone marrow hematopoietic cell lineages from mouse ESCs in a rat. - ESC-derived cells from mouse-rat chimeras were fully functional and exhibited normal gene expression signatures and cell surface markers.

developmental biology↗

Inflammatory blockade prevents injury to the developing pulmonary gas exchange surface in preterm primates

Malformations of or injuries to the developing lung are associated with perinatal morbidity and mortality with lifelong consequences for subsequent pulmonary health. One fetal exposure linked with poor health outcomes is chorioamnionitis, which impacts up to 25-40% of preterm births. Severe chorioamnionitis with prematurity is associated with significantly increased risk of pulmonary disease and secondary infections in childhood, suggesting that fetal inflammation may significantly alter developmental ontogeny of the lung. To test this hypothesis, we used intra-amniotic lipopolysaccharide (LPS, endotoxin) to generate experimental chorioamnionitis in prenatal Rhesus macaque (Macaca mulatta), a model which shares critical structural and temporal aspects of human lung development. Inflammatory injury directly disrupts the developing gas exchange surface of the primate lung, with extensive damage to alveolar structure, particularly the close association and coordinated differentiation of alveolar type 1 pneumocytes and specialized alveolar capillary endothelium. Single cell RNA sequencing analysis defined a multicellular alveolar signaling niche driving alveologenesis which was extensively disrupted by perinatal inflammation, leading to loss of gas exchange surface and alveolar simplification similar to that found in chronic lung disease of newborns. Blockade of IL1{beta} and TNF ameliorated endotoxin-induced inflammatory lung injury by blunting stromal response to inflammation and modulating innate immune activation in myeloid cells, restoring structural integrity and key signaling networks in the developing alveolus. These data provide new insight into the pathophysiology of developmental lung injury and suggest that modulating inflammation is a promising therapeutic approach to prevent fetal consequences of chorioamnionitis.

developmental biology↗