Arti Ahluwalia - Profile on Academia.edu (original) (raw)
Papers by Arti Ahluwalia
Frontiers in Bioengineering and Biotechnology, Apr 8, 2020
The mechanical properties of the cellular microenvironment play a crucial role in modulating cell... more The mechanical properties of the cellular microenvironment play a crucial role in modulating cell function, and many pathophysiological processes are accompanied by variations in extracellular matrix (ECM) stiffness. Lysyl oxidase (LOx) is one of the enzymes involved in several ECM-stiffening processes. Here, we engineered poly(ethylene glycol) (PEG)-based hydrogels with controlled mechanical properties in the range typical of soft tissues. These hydrogels were functionalized featuring free primary amines, which allows an additional chemical LOx-responsive behavior with increase in crosslinks and hydrogel elastic modulus, mimicking biological ECMstiffening mechanisms. Hydrogels with elastic moduli in the range of 0.5-4 kPa were obtained after a first photopolymerization step. The increase in elastic modulus of the functionalized and enzyme-responsive hydrogels was also characterized after the second-step enzymatic reaction, recording an increase in hydrogel stiffness up to 0.5 kPa after incubation with LOx. Finally, hydrogel precursors containing HepG2 (bioinks) were used to form three-dimensional (3D) in vitro models to mimic hepatic tissue and test PEG-based hydrogel biocompatibility. Hepatic functional markers were measured up to 7 days of culture, suggesting further use of such 3D models to study cell mechanobiology and response to dynamic variation of hydrogels stiffness. The results show that the functionalized hydrogels presented in this work match the mechanical properties of soft tissues, allow dynamic variations of hydrogel stiffness, and can be used to mimic changes in the microenvironment properties of soft tissues typical of inflammation and pathological changes at early stages (e.g., fibrosis, cancer).
Tissue Engineering, 2002
A technique for controlled deposition of biomaterials and cells in specific and complex architect... more A technique for controlled deposition of biomaterials and cells in specific and complex architectures is described. It employs a highly accurate three-dimensional micropositioning system with a pressure-controlled syringe to deposit biopolymer structures with a lateral resolution of 5 mm. The pressure-activated microsyringe is equipped with a fine-bore exit needle and a wide variety of two-and three-dimensional patterns on which cells to be deposited can adhere. The system has been characterized in terms of deposition parameters such as applied pressure, motor speed, line width and height, and polymer viscosity, and a fluid dynamic model simulating the deposition process has been developed, allowing an accurate prediction of the topological characteristics of the polymer structures.
Cell culture device for microwell plate and fluidics system
PAM2: A new Rapid Prototyping method for fabrication of bio-active hydrogel scaffolds
ABSTRACT oral
SpHyGa: Fabrication of Hepatic Lobule Replicas Using Tissue Derived Material Composites
Tissue Engineering Part a, Oct 1, 2008
A multicompartmental bioreactor was conceived and designed to mimic cross talk between cells in d... more A multicompartmental bioreactor was conceived and designed to mimic cross talk between cells in different culture chambers connected only by flow, such that cell-cell interaction is mediated by soluble ligands as occurs in the body. The system was tested with a connected culture of murine hepatocytes and human umbilical vein endothelial cells. Metabolites such as albumin, urea, lactate and viability were monitored during the course of the experiments and compared with monoculture conditions in the bioreactor. When the two cell types are placed in connected culture, there is an increase in endothelial cell viability and hepatic glucose synthesis as well as albumin and urea production, while overall lactate production in the system is downregulated. The results show that the multicompartmental bioreactor enhances cell function, effectively combining both heterotypic interactions with increased nutrient availability.
Report on Design and Implementation of ex- and in-vivo sensors
Update on in-Vivo Chemical Sensors and Optical Immunosensors
Rapid Prototyping Methods for Tissue Engineering Applications
Endotelizzazione di portesi vascolari polimeriche: Caratterizazzione biologica e meccanica
Microstructural imaging of the human claustrum
How engineers can help?
ABSTRACT
Artificial Polymeric Interfaces for Application to Biomaterials
Improvement of cell-polymer material interaction via antibody interface
Study of Sinthetic Surfaces for Promotion of Cellular Grow
Endothelial Cell Grow on Bioerodible Polymers for Application to Vascular Prostheses
Monitoring cell culture 3D microenvironments: oxygen and pH nano-sensors within hydrogels
Ratiometric pH and O2 nanosensors were fabricated independently using a fluorophore that produces... more Ratiometric pH and O2 nanosensors were fabricated independently using a fluorophore that produces a signal proportional to the concentration of the analyte of interest, and a second fluorophore that produces a reference signal, insensitive to the analyte of interest. These fluorophores emit at different wavelengths and were either entrapped or covalently bound, within an inert optically transparent polymeric matrix. In this work uniform sized 3D micro-scaled alginate hydrogel constructs of approximately 100-300 mumumum were fabricated. Through dual incorporation of HepG2 cells and nanosensors within these alginate constructs we aim to have a real-time, non-invasive method to measure microenvironmental pH and O2 content. Ratiometric fluorescent output from the microenvironment is used to monitor O2 concentrations and pH during cell culture. Measurements show that 3D micro-scaled constructs are suitable for cell growth and proliferation. Moreover O2 and pH values within the hydrogel cel...
Realisation of a concentration gradients cell chamber to study their effect of biomolecules on the cell activity
Realizzazione di strutture micro fabbricate tramite tecnica di micro Laser Sintering per applicazione alla Tissue Engineering
ABSTRACT oral
Realization of micro-structures fabricated through micro-laser ablation technique for application to Tissue Engineering
Frontiers in Bioengineering and Biotechnology, Apr 8, 2020
The mechanical properties of the cellular microenvironment play a crucial role in modulating cell... more The mechanical properties of the cellular microenvironment play a crucial role in modulating cell function, and many pathophysiological processes are accompanied by variations in extracellular matrix (ECM) stiffness. Lysyl oxidase (LOx) is one of the enzymes involved in several ECM-stiffening processes. Here, we engineered poly(ethylene glycol) (PEG)-based hydrogels with controlled mechanical properties in the range typical of soft tissues. These hydrogels were functionalized featuring free primary amines, which allows an additional chemical LOx-responsive behavior with increase in crosslinks and hydrogel elastic modulus, mimicking biological ECMstiffening mechanisms. Hydrogels with elastic moduli in the range of 0.5-4 kPa were obtained after a first photopolymerization step. The increase in elastic modulus of the functionalized and enzyme-responsive hydrogels was also characterized after the second-step enzymatic reaction, recording an increase in hydrogel stiffness up to 0.5 kPa after incubation with LOx. Finally, hydrogel precursors containing HepG2 (bioinks) were used to form three-dimensional (3D) in vitro models to mimic hepatic tissue and test PEG-based hydrogel biocompatibility. Hepatic functional markers were measured up to 7 days of culture, suggesting further use of such 3D models to study cell mechanobiology and response to dynamic variation of hydrogels stiffness. The results show that the functionalized hydrogels presented in this work match the mechanical properties of soft tissues, allow dynamic variations of hydrogel stiffness, and can be used to mimic changes in the microenvironment properties of soft tissues typical of inflammation and pathological changes at early stages (e.g., fibrosis, cancer).
Tissue Engineering, 2002
A technique for controlled deposition of biomaterials and cells in specific and complex architect... more A technique for controlled deposition of biomaterials and cells in specific and complex architectures is described. It employs a highly accurate three-dimensional micropositioning system with a pressure-controlled syringe to deposit biopolymer structures with a lateral resolution of 5 mm. The pressure-activated microsyringe is equipped with a fine-bore exit needle and a wide variety of two-and three-dimensional patterns on which cells to be deposited can adhere. The system has been characterized in terms of deposition parameters such as applied pressure, motor speed, line width and height, and polymer viscosity, and a fluid dynamic model simulating the deposition process has been developed, allowing an accurate prediction of the topological characteristics of the polymer structures.
Cell culture device for microwell plate and fluidics system
PAM2: A new Rapid Prototyping method for fabrication of bio-active hydrogel scaffolds
ABSTRACT oral
SpHyGa: Fabrication of Hepatic Lobule Replicas Using Tissue Derived Material Composites
Tissue Engineering Part a, Oct 1, 2008
A multicompartmental bioreactor was conceived and designed to mimic cross talk between cells in d... more A multicompartmental bioreactor was conceived and designed to mimic cross talk between cells in different culture chambers connected only by flow, such that cell-cell interaction is mediated by soluble ligands as occurs in the body. The system was tested with a connected culture of murine hepatocytes and human umbilical vein endothelial cells. Metabolites such as albumin, urea, lactate and viability were monitored during the course of the experiments and compared with monoculture conditions in the bioreactor. When the two cell types are placed in connected culture, there is an increase in endothelial cell viability and hepatic glucose synthesis as well as albumin and urea production, while overall lactate production in the system is downregulated. The results show that the multicompartmental bioreactor enhances cell function, effectively combining both heterotypic interactions with increased nutrient availability.
Report on Design and Implementation of ex- and in-vivo sensors
Update on in-Vivo Chemical Sensors and Optical Immunosensors
Rapid Prototyping Methods for Tissue Engineering Applications
Endotelizzazione di portesi vascolari polimeriche: Caratterizazzione biologica e meccanica
Microstructural imaging of the human claustrum
How engineers can help?
ABSTRACT
Artificial Polymeric Interfaces for Application to Biomaterials
Improvement of cell-polymer material interaction via antibody interface
Study of Sinthetic Surfaces for Promotion of Cellular Grow
Endothelial Cell Grow on Bioerodible Polymers for Application to Vascular Prostheses
Monitoring cell culture 3D microenvironments: oxygen and pH nano-sensors within hydrogels
Ratiometric pH and O2 nanosensors were fabricated independently using a fluorophore that produces... more Ratiometric pH and O2 nanosensors were fabricated independently using a fluorophore that produces a signal proportional to the concentration of the analyte of interest, and a second fluorophore that produces a reference signal, insensitive to the analyte of interest. These fluorophores emit at different wavelengths and were either entrapped or covalently bound, within an inert optically transparent polymeric matrix. In this work uniform sized 3D micro-scaled alginate hydrogel constructs of approximately 100-300 mumumum were fabricated. Through dual incorporation of HepG2 cells and nanosensors within these alginate constructs we aim to have a real-time, non-invasive method to measure microenvironmental pH and O2 content. Ratiometric fluorescent output from the microenvironment is used to monitor O2 concentrations and pH during cell culture. Measurements show that 3D micro-scaled constructs are suitable for cell growth and proliferation. Moreover O2 and pH values within the hydrogel cel...
Realisation of a concentration gradients cell chamber to study their effect of biomolecules on the cell activity
Realizzazione di strutture micro fabbricate tramite tecnica di micro Laser Sintering per applicazione alla Tissue Engineering
ABSTRACT oral
Realization of micro-structures fabricated through micro-laser ablation technique for application to Tissue Engineering