Mini-Column for Cytoadherence: A New Method for Measuring the Relative Size of Binding Subpopulations in Plasmodium Falciparum Isolates

Abstract

Background: Cytoadherence of Plasmodium falciparum- infected red blood cells to endothelial cells is an important mechanism for parasite survival and a major trigger for diseases pathology. Here, we de­scribe a new adhesion assay in which different cell types (CHO, CHO/CD36 and CHO/ICAM-1) are at­tached to Cytodex beads in a mini-column format to measure the relative sizes of various binding subpopula­tions as a percentage of the total population.Methods: Relative size of CD36 and ICAM-1-binding subpopulations of erythrocytes infected with P. falcipa­rum were measured by amount of parasitemia before and after passing the infected erythrocytes through a particular column.Results: The mini-column adhesion assay was a suitable method as parasitemia always reduced after pass­ing through a particular column in independent experiments. For example, in a typical experiment us­ing P. falciparum ITG line, 75% of the parasites are retained on a CHO/ICAM-1 while 0% of clone 3D7 is retained.Conclusion: This work introduced and validated a method for measuring the relative size of parasite bind­ing subpopulations and the selection of them. Also, the mini-column method is of value for assessments of cytoadherence and can be used as tool for different applications.

Keywords

• Cytoadherence
• CHO Cells
• P. Falciparum