Protection of the biconcave profile of human erythrocytes against osmotic damage by ultraviolet-A irradiation through membrane-cytoskeleton enhancement

Abstract

To perform various physiological functions, erythrocytes possess a unique biconcave shape provided by a special architecture of the membrane-skeleton system. In the present work, we use a simple irradiation method to treat human erythrocytes with 365 nm ultraviolet-A (UVA) light at the single-cell level in vitro. Depending on the irradiation dose, UVA show protection of the biconcave profile against the detrimental action of distilled water. This protective effect can also be confirmed for saponin that damages the membrane-skeleton by vesiculation and pore formation. Interestingly, at two irradiation doses of UVA pretreatment, erythrocytes still seem to exhibit cell viability as tested by trypan blue assay even if distilled water or saponin is added. The oxidants hydrogen peroxide and cumene hydroperoxide partly simulate the protective effects. Taken together, these results demonstrate that 365 nm UVA irradiation can protect the biconcave profile of human erythrocytes through membrane-skeleton enhancement associated with a production of oxidants.

Deep-Learning Terahertz Single-Cell Metabolic Viability Study

“…32 Because trypan blue can only stain dead cells with damaged membranes, it cannot stain live cells with impermeable membranes. 33 Cell viability is generally defined as a percentage of living cells in a whole population. 34 However, some cells that have lost their metabolic capacity but have not died are identified as living cells, resulting in inaccurate cell viability assessments.…”

“…The trypan blue method is the gold standard for calculating cell viability but is inaccurate for assessing cell viability below 80% . Because trypan blue can only stain dead cells with damaged membranes, it cannot stain live cells with impermeable membranes . Cell viability is generally defined as a percentage of living cells in a whole population .…”

A bioactive nanocomposite integrated specific TAMs target and synergistic TAMs repolarization for effective cancer immunotherapy

“…It has been shown that ROS can impact the polarization and activation of M1-like macrophages by regulating the signal transduction pathways of mitogen-activated protein kinase (MAPK) and NF- κ B, which are linked to pro-inflammatory gene expression [ [15] , [16] , [17] ]. Furthermore, ROS generation can be stimulated through light irradiation, resulting in a targeted and localized effect with minimal adverse effects [ 18 , 19 ]. In immunotherapy, small molecule drugs, particularly ROS photosensitizers, have gained prominence [ 20 ].…”