Role of membrane undulations in cell adhesion.

Abstract

Human Red Blood Cells (RBC) undergo several physicochemical changes, in the course of their life span of approximately 120 days. The increased aggregation of senescent RBC continues to be of great interest to clinicians and scientists. Hence, this project aimed to give more insight into the topic, through the observation of RBC treated with varying concentrations the enzyme Neuraminidase, to mimic RBC ageing to differing extents. Through the use of a suitable imaging modality, the Interference Reflection Microscope (IRM), RBC were for quantified with respect to their undulation amplitudes and adhesion energies

In this project, RBC were allowed to adhere onto albumin-coated glass in solutions of Phosphate Buffered Saline (PBS) with 0.2% Bovine Serum Albumin (BSA), as well as 1g/dL 40K Dextran and 1g/dL 70L Dextran.

The results reflected that senescent RBC showed more pronounced increased adhesion in Dextran of lower molecular weight, as compared to a larger Dextran. Undulation forces were also suppressed in larger Dextran. Overall, the results agreed with the depletion-layer model to a significant extent, revealing that depletion interaction might be a key driving factor behind elevated RBC aggregation or adhesion to surfaces.