Max Salick - Academia.edu (original) (raw)
Papers by Max Salick
ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart... more ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart cells, but implementing mechanical cues in an appropriate context during differentiation of human pluripotent stem cells (hPSCs) to cardiomyocytes remains challenging. We used polyacrylamide hydrogels as a model system to investigate the effects of substrate mechanics on differentiation and functionality of cardiomyocytes generated from hPSCs. By changing the concentration of crosslinker in our polyacrylamide hydrogels, we obtained substrates with a physiologically relevant range of stiffnesses. We plated hPSCs undergoing embryoid body-based differentiation onto the hydrogels and observed that cardiogenesis peaks on substrates of intermediate stiffness. To investigate the effects of substrate stiffness on contractility, we added fluorescent beads to the surface of the hydrogels, which act as optical trackers for the movement of contracting cells. We used traction force microscopy to quantify the contraction stress of singularized cardiomyocytes cultured on a range of stiffnesses. In primary rat cardiomyocytes, we observed that contraction stress increases with substrate stiffness. We observed the same trend in cardiomyocytes derived from hPSCs, providing an indication of their similarity to native, fully differentiated cardiomyocytes. These results demonstrate that hPSCs and their cardiomyocyte derivatives can respond to substrate mechanics. Our approaches for investigating and quantifying this response may aid in the development of novel culture systems for effective differentiation of functional cardiomyocytes from hPSCs.
Circulation, Nov 25, 2014
Cell stem cell, Jan 10, 2016
Several studies have reported reprogramming of fibroblasts into induced cardiomyocytes; however, ... more Several studies have reported reprogramming of fibroblasts into induced cardiomyocytes; however, reprogramming into proliferative induced cardiac progenitor cells (iCPCs) remains to be accomplished. Here we report that a combination of 11 or 5 cardiac factors along with canonical Wnt and JAK/STAT signaling reprogrammed adult mouse cardiac, lung, and tail tip fibroblasts into iCPCs. The iCPCs were cardiac mesoderm-restricted progenitors that could be expanded extensively while maintaining multipotency to differentiate into cardiomyocytes, smooth muscle cells, and endothelial cells in vitro. Moreover, iCPCs injected into the cardiac crescent of mouse embryos differentiated into cardiomyocytes. iCPCs transplanted into the post-myocardial infarction mouse heart improved survival and differentiated into cardiomyocytes, smooth muscle cells, and endothelial cells. Lineage reprogramming of adult somatic cells into iCPCs provides a scalable cell source for drug discovery, disease modeling, a...
ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart... more ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart cells, but implementing mechanical cues in an appropriate context during differentiation of human pluripotent stem cells (hPSCs) to cardiomyocytes remains challenging. We used polyacrylamide hydrogels as a model system to investigate the effects of substrate mechanics on differentiation and functionality of cardiomyocytes generated from hPSCs. By changing the concentration of crosslinker in our polyacrylamide hydrogels, we obtained substrates with a physiologically relevant range of stiffnesses. We plated hPSCs undergoing embryoid body-based differentiation onto the hydrogels and observed that cardiogenesis peaks on substrates of intermediate stiffness. To investigate the effects of substrate stiffness on contractility, we added fluorescent beads to the surface of the hydrogels, which act as optical trackers for the movement of contracting cells. We used traction force microscopy to quantify the contraction stress of singularized cardiomyocytes cultured on a range of stiffnesses. In primary rat cardiomyocytes, we observed that contraction stress increases with substrate stiffness. We observed the same trend in cardiomyocytes derived from hPSCs, providing an indication of their similarity to native, fully differentiated cardiomyocytes. These results demonstrate that hPSCs and their cardiomyocyte derivatives can respond to substrate mechanics. Our approaches for investigating and quantifying this response may aid in the development of novel culture systems for effective differentiation of functional cardiomyocytes from hPSCs.
Prior work on many cell types, including stem cells, has definitively shown that mechanical stiff... more Prior work on many cell types, including stem cells, has definitively shown that mechanical stiffness of the neighboring material and the overall stress state influences cell behavior. There is also evidence that the topology (i.e. 2D vs 3D environment) impacts cell behavior. Our research involves controlling the differentiation of human embryonic stem cells (hESCs) through mechanical stimuli. We employ three-dimensional
International Journal of Cell Biology, 2012
Cell stem cell, 2016
Zika virus (ZIKV) can cross the placental barrier, resulting in infection of the fetal brain and ... more Zika virus (ZIKV) can cross the placental barrier, resulting in infection of the fetal brain and neurological defects including microcephaly. The cellular tropism of ZIKV and the identity of attachment factors used by the virus to gain access to key cell types involved in pathogenesis are under intense investigation. Initial studies suggested that ZIKV preferentially targets neural progenitor cells (NPCs), providing an explanation for the developmental phenotypes observed in some pregnancies. The AXL protein has been nominated as a key attachment factor for ZIKV in several cell types including NPCs. However, here we show that genetic ablation of AXL has no effect on ZIKV entry or ZIKV-mediated cell death in human induced pluripotent stem cell (iPSC)-derived NPCs or cerebral organoids. These findings call into question the utility of AXL inhibitors for preventing birth defects after infection and suggest that further studies of viral attachment factors in NPCs are needed.
ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart... more ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart cells, but implementing mechanical cues in an appropriate context during differentiation of human pluripotent stem cells (hPSCs) to cardiomyocytes remains challenging. We used polyacrylamide hydrogels as a model system to investigate the effects of substrate mechanics on differentiation and functionality of cardiomyocytes generated from hPSCs. By changing the concentration of crosslinker in our polyacrylamide hydrogels, we obtained substrates with a physiologically relevant range of stiffnesses. We plated hPSCs undergoing embryoid body-based differentiation onto the hydrogels and observed that cardiogenesis peaks on substrates of intermediate stiffness. To investigate the effects of substrate stiffness on contractility, we added fluorescent beads to the surface of the hydrogels, which act as optical trackers for the movement of contracting cells. We used traction force microscopy to quantify the contraction stress of singularized cardiomyocytes cultured on a range of stiffnesses. In primary rat cardiomyocytes, we observed that contraction stress increases with substrate stiffness. We observed the same trend in cardiomyocytes derived from hPSCs, providing an indication of their similarity to native, fully differentiated cardiomyocytes. These results demonstrate that hPSCs and their cardiomyocyte derivatives can respond to substrate mechanics. Our approaches for investigating and quantifying this response may aid in the development of novel culture systems for effective differentiation of functional cardiomyocytes from hPSCs.
Circulation, Nov 25, 2014
Cell stem cell, Jan 10, 2016
Several studies have reported reprogramming of fibroblasts into induced cardiomyocytes; however, ... more Several studies have reported reprogramming of fibroblasts into induced cardiomyocytes; however, reprogramming into proliferative induced cardiac progenitor cells (iCPCs) remains to be accomplished. Here we report that a combination of 11 or 5 cardiac factors along with canonical Wnt and JAK/STAT signaling reprogrammed adult mouse cardiac, lung, and tail tip fibroblasts into iCPCs. The iCPCs were cardiac mesoderm-restricted progenitors that could be expanded extensively while maintaining multipotency to differentiate into cardiomyocytes, smooth muscle cells, and endothelial cells in vitro. Moreover, iCPCs injected into the cardiac crescent of mouse embryos differentiated into cardiomyocytes. iCPCs transplanted into the post-myocardial infarction mouse heart improved survival and differentiated into cardiomyocytes, smooth muscle cells, and endothelial cells. Lineage reprogramming of adult somatic cells into iCPCs provides a scalable cell source for drug discovery, disease modeling, a...
ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart... more ABSTRACT The mechanical microenvironment plays a role in proper development and function of heart cells, but implementing mechanical cues in an appropriate context during differentiation of human pluripotent stem cells (hPSCs) to cardiomyocytes remains challenging. We used polyacrylamide hydrogels as a model system to investigate the effects of substrate mechanics on differentiation and functionality of cardiomyocytes generated from hPSCs. By changing the concentration of crosslinker in our polyacrylamide hydrogels, we obtained substrates with a physiologically relevant range of stiffnesses. We plated hPSCs undergoing embryoid body-based differentiation onto the hydrogels and observed that cardiogenesis peaks on substrates of intermediate stiffness. To investigate the effects of substrate stiffness on contractility, we added fluorescent beads to the surface of the hydrogels, which act as optical trackers for the movement of contracting cells. We used traction force microscopy to quantify the contraction stress of singularized cardiomyocytes cultured on a range of stiffnesses. In primary rat cardiomyocytes, we observed that contraction stress increases with substrate stiffness. We observed the same trend in cardiomyocytes derived from hPSCs, providing an indication of their similarity to native, fully differentiated cardiomyocytes. These results demonstrate that hPSCs and their cardiomyocyte derivatives can respond to substrate mechanics. Our approaches for investigating and quantifying this response may aid in the development of novel culture systems for effective differentiation of functional cardiomyocytes from hPSCs.
Prior work on many cell types, including stem cells, has definitively shown that mechanical stiff... more Prior work on many cell types, including stem cells, has definitively shown that mechanical stiffness of the neighboring material and the overall stress state influences cell behavior. There is also evidence that the topology (i.e. 2D vs 3D environment) impacts cell behavior. Our research involves controlling the differentiation of human embryonic stem cells (hESCs) through mechanical stimuli. We employ three-dimensional
International Journal of Cell Biology, 2012
Cell stem cell, 2016
Zika virus (ZIKV) can cross the placental barrier, resulting in infection of the fetal brain and ... more Zika virus (ZIKV) can cross the placental barrier, resulting in infection of the fetal brain and neurological defects including microcephaly. The cellular tropism of ZIKV and the identity of attachment factors used by the virus to gain access to key cell types involved in pathogenesis are under intense investigation. Initial studies suggested that ZIKV preferentially targets neural progenitor cells (NPCs), providing an explanation for the developmental phenotypes observed in some pregnancies. The AXL protein has been nominated as a key attachment factor for ZIKV in several cell types including NPCs. However, here we show that genetic ablation of AXL has no effect on ZIKV entry or ZIKV-mediated cell death in human induced pluripotent stem cell (iPSC)-derived NPCs or cerebral organoids. These findings call into question the utility of AXL inhibitors for preventing birth defects after infection and suggest that further studies of viral attachment factors in NPCs are needed.