Search for: All records

Despite chronic fibrosis occurring in many pathological conditions, few in vitro studies examine how fibrosis impacts lymphatic endothelial cell (LEC) behavior. This study examined stiffening profiles of PhotoCol®—commercially available methacrylated type I collagen—photo-crosslinked with the photoinitiators: Lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP), Irgacure 2959 (IRG), and Ruthenium/Sodium Persulfate (Ru/SPS) prior to evaluating PhotoCol® permeability and LEC response to PhotoCol® at stiffnesses representing normal and fibrotic tissues. Ru/SPS produced the highest stiffness (~6 kilopascal (kPa)) for photo-crosslinked PhotoCol®, but stiffness did not change with burst light exposures (30 and 90 s). The collagen fibril area fraction increased, and dextran permeability (40 kilodalton (kDa)) decreased with photo-crosslinking, showing the impact of photo-crosslinking on microstructure and molecular transport. Human dermal LECs on softer, uncrosslinked PhotoCol® (~0.5 kPa) appeared smaller with less prominent vascular endothelial (VE)-cadherin (cell–cell junction) expression compared to LECs on stiffer PhotoCol® (~6 kPa), which had increased cell size, border irregularity, and VE-cadherin thickness (junction zippering) that is consistent with LEC morphology in fibrotic tissues. Our quantitative morphological analysis demonstrates our ability to produce LECs with a fibrotic phenotype, and the overall study shows that PhotoCol® with Ru/SPS provides the necessary physical properties to systematically study LEC responses related to capillary growth and function under fibrotic conditions. 

In the United States, underbounded communities—urban disadvantaged unincorporated neighborhoods characterized by high-poverty and high residential density lying just outside the border of an incorporated municipality—often lack consistent access to clean and safe water. Poor water quality and inadequate infrastructure shape residents’ risk perceptions, often leading to tap water mistrust, but little is known about the broader social, political, and economic drivers of water quality in these settings or about how such drivers inform the social construction of risk across different stakeholder groups. Using an underbounded African-American/Hispanic neighborhood in the Tampa Bay metropolitan region as a case study, we illustrate how tap water mistrust is socially constructed and how these constructions contrast between neighborhood residents and government officials. Interviews and participant observation with these groups reveal that tap water mistrust emerges from the nexus of inadequate infrastructure, poor housing conditions, challenges relating to the affordability of piped water, and jurisdictional disconnects. We call for interventions that foreground participatory research, integrate social and cultural context into technical solutions, and prioritize equitability in decision making.