Quantitation of cell membrane antigens at the single cell level. I. Microfluorometric analysis of reaction patterns in various test systems, with special reference to the mobility of the cell membrane.

Abstract

Miczofluorometry was used in an attempt to quantitate the intensity of membrane immunofluorcscence (IF) on single animal cells. Some experimental variables of importance to this method were analysed. Based on the data obtained, measurements per unit cell surface area were considered to be more useful than registrations per whole cell. The intensity of staining and pattern of IF distribution on the cell surface were studied in 15 test systems. All systems studied by the direct IF method showed decreasing intensity curves (intensity of staining versus antibody concentration) without prozone effect, whereas most indirect test systems showed prozone. The experimental variables that determined the intensity per unit cell surface area and staining pattern of the cells were temperature, time of incubaton, antibody concentration, and cell metabolism. The results indicated that the variation of the intensity registrations may provide a measure of the staining pattern. In addition, the variation of the intensity registrations seemed to reflect the heterogeneity of the cell types studied with regard to the amount of membrane antigen per cell.