A simple and intuitive methodology for estimating red blood cell surface antigen expression variation using optical cell-detachment technique

The analysis of surface antigens on cells, especially red blood cells (RBCs), has attracted increasing attention due to the recognition of antigenic variation that can facilitate early diagnoses. This paper presents an alternative methodology to estimate the variation of surface antigen expressions using an optical cell-detachment technique to validate the binding of individual RBCs stuck on corresponding antibody-coated surfaces. The detachment tests were implemented by an optical tweezers with gradually decreasing laser powers associated with serial antibody dilutions. Then, the antigen expression variation was estimated based on the known antibody dilution folds. The B- and B3-types of RBCs were selected for the demonstration subjects. With the semi-quantitative analysis, the proposed methodology was successfully verified for evaluating the variation of the RBC surface antigen expressions. The analysis result shows good consistency with the literature’s findings.