Sawan Jha

All Publications

• Protocol for efficient generation of human artery and vein endothelial cells from pluripotent stem cells. STAR protocols Loh, K. M., Zheng, S. L., Liu, K. J., Yin, Q., Amir-Ugokwe, Z. A., Jha, S. K., Qi, Y., Wazny, V. K., Nguyen, A. T., Chen, A., Njunkeng, F. M., Cheung, C., Spiekerkoetter, E., Red-Horse, K., Ang, L. T. 2024; 6 (1): 103494

  Abstract

  Blood vessels permeate all organs and execute myriad roles in health and disease. Here, we present a protocol to efficiently generate human artery and vein endothelial cells (ECs) from pluripotent stem cells within 3-4 days of differentiation. We delineate how to seed human pluripotent stem cells and sequentially differentiate them into primitive streak, lateral mesoderm, and either artery or vein ECs. We differentiate stem cells in defined, serum-free culture media in monolayers, without feeder cells or genetic manipulations. For complete details on the use and execution of this protocol, please refer to Ang et al. 1.

  View details for DOI 10.1016/j.xpro.2024.103494

  View details for PubMedID 39705146

• Lymphangiogenesis requires Ang2/Tie/PI3K signaling for VEGFR3 cell-surface expression JOURNAL OF CLINICAL INVESTIGATION Korhonen, E. A., Murtomaki, A., Jha, S., Anisimov, A., Pink, A., Zhang, Y., Stritt, S., Liaqat, I., Stanczuk, L., Alderfer, L., Sun, Z., Kapiainen, E., Singh, A., Sultan, I., Lantta, A., Leppanen, V., Eklund, L., He, Y., Augustin, H. G., Vaahtomeri, K., Saharinen, P., Makinen, T., Alitalo, K. 2022; 132 (15)

  Abstract

  Vascular endothelial growth factor C (VEGF-C) induces lymphangiogenesis via VEGF receptor 3 (VEGFR3), which is encoded by the most frequently mutated gene in human primary lymphedema. Angiopoietins (Angs) and their Tie receptors regulate lymphatic vessel development, and mutations of the ANGPT2 gene were recently found in human primary lymphedema. However, the mechanistic basis of Ang2 activity in lymphangiogenesis is not fully understood. Here, we used gene deletion, blocking Abs, transgene induction, and gene transfer to study how Ang2, its Tie2 receptor, and Tie1 regulate lymphatic vessels. We discovered that VEGF-C-induced Ang2 secretion from lymphatic endothelial cells (LECs) was involved in full Akt activation downstream of phosphoinositide 3 kinase (PI3K). Neonatal deletion of genes encoding the Tie receptors or Ang2 in LECs, or administration of an Ang2-blocking Ab decreased VEGFR3 presentation on LECs and inhibited lymphangiogenesis. A similar effect was observed in LECs upon deletion of the PI3K catalytic p110α subunit or with small-molecule inhibition of a constitutively active PI3K located downstream of Ang2. Deletion of Tie receptors or blockade of Ang2 decreased VEGF-C-induced lymphangiogenesis also in adult mice. Our results reveal an important crosstalk between the VEGF-C and Ang signaling pathways and suggest new avenues for therapeutic manipulation of lymphangiogenesis by targeting Ang2/Tie/PI3K signaling.

  View details for DOI 10.1172/JCI155478

  View details for Web of Science ID 000842455700004

  View details for PubMedID 35763346

  View details for PubMedCentralID PMC9337826

• Blood flow modeling reveals improved collateral artery performance during the regenerative period in mammalian hearts. Nature cardiovascular research Anbazhakan, S., Rios Coronado, P. E., Sy-Quia, A. N., Seow, L. W., Hands, A. M., Zhao, M., Dong, M. L., Pfaller, M. R., Amir, Z. A., Raftrey, B. C., Cook, C. K., D'Amato, G., Fan, X., Williams, I. M., Jha, S. K., Bernstein, D., Nieman, K., Pașca, A. M., Marsden, A. L., Horse, K. R. 2022; 1 (8): 775-790

  Abstract

  Collateral arteries bridge opposing artery branches, forming a natural bypass that can deliver blood flow downstream of an occlusion. Inducing coronary collateral arteries could treat cardiac ischemia, but more knowledge on their developmental mechanisms and functional capabilities is required. Here we used whole-organ imaging and three-dimensional computational fluid dynamics modeling to define spatial architecture and predict blood flow through collaterals in neonate and adult mouse hearts. Neonate collaterals were more numerous, larger in diameter and more effective at restoring blood flow. Decreased blood flow restoration in adults arose because during postnatal growth coronary arteries expanded by adding branches rather than increasing diameters, altering pressure distributions. In humans, adult hearts with total coronary occlusions averaged 2 large collaterals, with predicted moderate function, while normal fetal hearts showed over 40 collaterals, likely too small to be functionally relevant. Thus, we quantify the functional impact of collateral arteries during heart regeneration and repair-a critical step toward realizing their therapeutic potential.

  View details for DOI 10.1038/s44161-022-00114-9

  View details for PubMedID 37305211

  View details for PubMedCentralID PMC10256232