INVESTIGADORES
LEAL DENIS Maria Florencia
congresos y reuniones científicas
Título:
A biomimetic device combining microfluidics with nanotechnology allows studying the adhesion of erythrocytes to blood vessels.
Autor/es:
SAFFIOTI, NICOLÁS ANDRÉS*; LEAL DENIS, MARÍA FLORENCIA; HERLAX, VANESA; SCHWARZBAUM, PABLO JULIO; PALLAROLA, DIEGO
Reunión:
Congreso; XLIX REUNION ANUAL SAB; 2021
Resumen:
The alpha-hemolysin of Escherichia coli (HlyA), induces the translocation of phosphatidylserine (PS) from the internal to the external layer of the plasma membrane of erythrocytes. On the other hand, during the malaria disease, Plasmodium falciparum grows inside erythrocytes and synthesizes proteins, like PfEMP1, that translocate to the erythrocyte membrane at specific membrane knobs. P.falciparum proteins and PS in the erythrocytes plasma membrane bind to specific proteins expressed by the endothelium, thereby inducing erythrocytes adhesion, a process that can lead to vascular obstruction and thrombotic events in vivo. However, many aspects of the adhesion of erythrocytes are not yet understood. To investigate the adhesion mechanism in controlled conditions, we designed a biomimetic device that emulates the capillary architecture and the expression of adhesive molecules by the activated ECs.Microfluidic chips were prepared in PDMS using molds fabricated by photolithography. The microfluidic chip was adhered to a glass surface by O2 plasma treatment. The inner surface of the microfluidic channels was coated with the copolymer PLL-g-PEG-NTA. We followed the surface functionalization by quartz microbalance and fluorescence microscopy using a GFP-His Tag. Then, we studied the adhesion of erythrocytes incubated with HlyA to a device functionalized with Annexin V-His Tag, at different controlled flows. We also studied the adhesion of P.falciparum-infected erythrocytes to a surface coated with CD36. Only the P.falciparum-infected erythrocytes displayed a higher adhesion to surfaces in comparison to non-treated erythrocytes. The infected erythrocytes remain adhered to the surface even at shear stresses up to 8 dyn/cm2. Our preliminary results show that we can replicate the pathological adhesion of malaria-infected erythrocytes observed in tissues with this device. Future experiments will test the infected erythrocytes adhesion to surfaces where CD36 distribution on the surface is controlled at the nanometer scale using nanostructured surfaces.