title: New insights into the altered adhesive and mechanical properties of red blood cells parasitized by Babesia bovis.
abstract: Sequestration of parasite-infected red blood cells (RBCs) in the microvasculature is an important pathological feature of both bovine babesiosis caused by Babesia bovis and human malaria caused by Plasmodium falciparum. Surprisingly, when compared with malaria, the cellular and molecular mechanisms that underlie this abnormal circulatory behaviour for RBCs infected with B. bovis have been relatively ignored. Here, we present some novel insights into the adhesive and mechanical changes that occur in B. bovis-infected bovine RBCs and compare them with the alterations that occur in human RBCs infected with P. falciparum. After infection with B. bovis, bovine RBCs become rigid and adhere to vascular endothelial cells under conditions of physiologically relevant flow. These alterations are accompanied by the appearance of ridge-like structures on the RBC surface that are analogous, but morphologically and biochemically different, to the knob-like structures on the surface of human RBCs infected with P. falciparum. Importantly, albeit for a limited number of parasite lines examined here, the extent of these cellular and rheological changes appear to be related to parasite virulence. Future investigations to identify the precise molecular composition of ridges and the proteins that mediate adhesion will provide important insight into the pathogenesis of both babesiosis and malaria.
authors.affiliation: Department of Microbiology, Monash University, Victoria, Australia.
authors.forename: Claire L
authors.initials: CL
authors.lastname: Hutchings
authors.forename: Ang
authors.initials: A
authors.lastname: Li
authors.forename: Kate M
authors.initials: KM
authors.lastname: Fernandez
authors.forename: Taryn
authors.initials: T
authors.lastname: Fletcher
authors.forename: Louise A
authors.initials: LA
authors.lastname: Jackson
authors.forename: John B
authors.initials: JB
authors.lastname: Molloy
authors.forename: Wayne K
authors.initials: WK
authors.lastname: Jorgensen
authors.forename: Chwee T
authors.initials: CT
authors.lastname: Lim
authors.forename: Brian M
authors.initials: BM
authors.lastname: Cooke
mesh_terms: D000818:Animals; D016793:Babesia bovis / Q000254:growth & development / Q000472:pathogenicity / Q000502:physiology* / Q000648:ultrastructure; D001696:Biomechanical Phenomena; D002417:Cattle; D002448:Cell Adhesion; D042783:Endothelial Cells / Q000166:cytology; D004910:Erythrocyte Membrane / Q000469:parasitology / Q000648:ultrastructure; D004912:Erythrocytes / Q000166:cytology* / Q000469:parasitology* / Q000648:ultrastructure; D006801:Humans; D008018:Life Cycle Stages; D018625:Microscopy, Atomic Force; D010271:Parasites / Q000254:growth & development / Q000472:pathogenicity / Q000648:ultrastructure; D013499:Surface Properties; D014357:Trypsin / Q000378:metabolism; D014774:Virulence
chemical_list: D014357:Trypsin