The erythrocytes play an important role in the human body. The healthy erythrocytes can undergo extremely large deformation while passing through small capillaries. Their infection by Malaria Plasmodium falcipurum (P...The erythrocytes play an important role in the human body. The healthy erythrocytes can undergo extremely large deformation while passing through small capillaries. Their infection by Malaria Plasmodium falcipurum (P.f.) will lead to capillary blockage and blood flow obstruction. Many experimental and computational methods have been applied to study the increase in stickiness and decrease in deformability of the Malaria (P.f.) infected erythrocytes. The novelty of this paper lies in the establishment of an multi-component model for investigating mechanical properties of Malaria (P.f.) infected erythrocytes, especially of their enclosed parasites. Finite element method was applied to simulate the erythrocytes' deformation in micropipette aspiration and optical tweezers stretching using the computational software ABAQUS. The comparisons between simulations and experiments were able to quantitatively conclude the effects of stiffness and stickiness of the parasitophorous vacuole membrane on the cells' deformation, which could not be obtained from experiments directly.展开更多
Immune evasion is a strategy used by pathogenic microbes to evade the host immune system in order to ensure successful propagation. Immune evasion is particularly important for the blood stages of Plasmodium falciparu...Immune evasion is a strategy used by pathogenic microbes to evade the host immune system in order to ensure successful propagation. Immune evasion is particularly important for the blood stages of Plasmodium falciparum, the causative agent of the deadly disease malaria tropica. Because Plasmodium blood stage parasites require human erythrocytes for replication, their ability to evade attack by the human immune system is essential for parasite survival. In order to escape immunity-induced killing, the intraerythrocytic parasites have evolved a variety of evasion mechanisms, including expansion of plasmodial surface proteins, organ-specific sequestration of the infected red blood cells and acquisition of immune-regulatory proteins by the parasite. This review aims to highlight recent advances in the molecular understanding of the immune evasion strategies by P. falciparum, including antigenic variation, surface protein polymorphisms and invasion ligand diversification. The review will further discuss new findings on the regulatory mechanisms applied by P. falciparum to avoid lysis by the human complement as well as killing by immune factors of the mosquito vector.展开更多
基金supported by the National Natural Science Foundation of China (11072178,11172214)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry,and Shanghai Leading Academic Discipline Project (B302)
文摘The erythrocytes play an important role in the human body. The healthy erythrocytes can undergo extremely large deformation while passing through small capillaries. Their infection by Malaria Plasmodium falcipurum (P.f.) will lead to capillary blockage and blood flow obstruction. Many experimental and computational methods have been applied to study the increase in stickiness and decrease in deformability of the Malaria (P.f.) infected erythrocytes. The novelty of this paper lies in the establishment of an multi-component model for investigating mechanical properties of Malaria (P.f.) infected erythrocytes, especially of their enclosed parasites. Finite element method was applied to simulate the erythrocytes' deformation in micropipette aspiration and optical tweezers stretching using the computational software ABAQUS. The comparisons between simulations and experiments were able to quantitatively conclude the effects of stiffness and stickiness of the parasitophorous vacuole membrane on the cells' deformation, which could not be obtained from experiments directly.
文摘Immune evasion is a strategy used by pathogenic microbes to evade the host immune system in order to ensure successful propagation. Immune evasion is particularly important for the blood stages of Plasmodium falciparum, the causative agent of the deadly disease malaria tropica. Because Plasmodium blood stage parasites require human erythrocytes for replication, their ability to evade attack by the human immune system is essential for parasite survival. In order to escape immunity-induced killing, the intraerythrocytic parasites have evolved a variety of evasion mechanisms, including expansion of plasmodial surface proteins, organ-specific sequestration of the infected red blood cells and acquisition of immune-regulatory proteins by the parasite. This review aims to highlight recent advances in the molecular understanding of the immune evasion strategies by P. falciparum, including antigenic variation, surface protein polymorphisms and invasion ligand diversification. The review will further discuss new findings on the regulatory mechanisms applied by P. falciparum to avoid lysis by the human complement as well as killing by immune factors of the mosquito vector.