2016 Real-time measurement of Plasmodium falciparum-infected erythrocyte cytoadhesion with a quartz crystal microbalance

Authors:  Kömpf D1,4, Held J2,3, Müller SF1,  Drechsel HR1,5, Tschan SC2,3, Northoff H1, Mordmüller B2,3, Gehring FK1,5

Journal:  Malaria Journal 2016, 15:317, DOI: 10.1186/s12936-016-1374-7


1 Biosensor Research Group, Institute of Clinical and Experimental Transfusion Medicine, University Hospital of Tübingen, Tübingen, Germany.

2 Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.

3 DZIF–Deutsches Zentrum für Infektionsforschung, Standort Tübingen, Germany.

4 Present Address: State Health Office Baden-Württemberg, Stuttgart, Germany.

5 Present Address: 3T GmbH & Co KG, Tuttlingen, Germany.



An important virulence mechanism of the malaria parasite Plasmodium falciparumis cytoadhesion, the binding of infected erythrocytes to endothelial cells in the second half of asexual blood stage development. Conventional methods to investigate adhesion of infected erythrocytes are mostly performed under static conditions, many are based on manual or semi-automated read-outs and are, therefore, difficult to standardize. Quartz crystal microbalances (QCM) are sensitive to nanogram-scale changes in mass and biomechanical properties and are increasingly used in biomedical research. Here, the ability of QCM is explored to measure binding of P. falciparum-infected erythrocytes to two receptors: CD36 and chondroitin sulfate A (CSA) under flow conditions.


Binding of late stage P. falciparum parasites is measured in comparison to uninfected erythrocytes to CD36- and CSA-coated quartzes by QCM observing frequency shifts. CD36-expressing cell membrane fragments and CSA polysaccharide were coated via poly-l-lysine to the quartz. The method was validated by microscopic counting of attached parasites and of erythrocytes to the coated quartzes.


Frequency shifts indicating binding of infected erythrocytes could be observed for both receptors CD36 and CSA. The frequency shifts seen for infected and uninfected erythrocytes were strongly correlated to the microscopically counted numbers of attached cells.


In this proof-of-concept experiment it is shown that QCM is a promising tool to measure binding kinetics and specificity of ligand-receptor interactions using viable, parasite-infected erythrocytes. The method can improve the understanding of the virulence of P. falciparum and might be used to cross-validate other methods.


Malaria, PfEMP1, Cytoadhesion, Thickness shear mode sensors, Biosensor, CSA, CD36