A luminescence method for the quantitative determination of phagocytosis of erythrocytes, of malaria-parasitized erythrocytes and of malarial pigment.

A method is described for the quantitative measurement of phagocytosis of human erythrocytes, malaria-parasitized erythrocytes and isolated malarial pigment by adherent human monocytes. The method utilizes measurement of haem-elicited luminescence both for the assay of ingested haemoglobin or malarial pigment haem and for the quantification of adherent monocytes. The latter is based on assay of luminescence elicited by cytochrome haem. The method utilizes the same low-cost reagents and equipment for assay of ingested haem and for quantification of adherent monocytes. The method is fast and extremely sensitive. The lower sensitivity limit is 500 monocytes and 10 RBC, or RBC equivalents in the case of malarial pigment, per assay. A detailed protocol with full calculations of a typical phagocytosis experiment of oxidatively damaged RBC, malarial pigment and control RBS is presented.