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| Author(s): |
Flávia Menezes Zimbres
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) |
| Defense date: | 2016-11-10 |
| Examining board members: |
Carsten Wrenger;
Renato Barboza;
Daniel Youssef Bargieri;
Silvia Beatriz Boscardin;
Josiane Cardoso
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| Advisor: | Carsten Wrenger |
| Abstract | |
The human malaria is a mosquito-borne infectious disease associated with a high risk of mortality. Among the parasite species that causes human malaria, Plasmodium falciparum is responsible by 90% of the lethal cases. The virulence of this pathogen is associated with host cell modifications by trafficking proteins to the surface of infected erythrocytes. Aiming to interfere with these proteins we have applied the Cell-SELEX (Systematic Evolution of Ligands by Exponential Enrichment) technology. After iterative cycles of selection we obtained single stranded DNA molecules, known as aptamers, with high binding affinity and specificity against protein targets present in the surface of erythrocytes infected with P. falciparum. Pull-down assays using the selected aptamers in a streptavidin-biotin affinity assay followed by mass spectrometry analysis revealed the interaction of these DNA molecules with proteins such as RIFIN, PfEMP, RAP1, among others embedded in the surface of infected erythrocytes. As consequence of these interactions, the selected aptamers demonstrated to be potent inhibitors of parasite proliferation, as validated by in vitro tests. Another strategy used was the production of aptamers against the recombinantly expressed plasmodial pyridoxal kinase (PfPdxK). Using both protein-SELEX as well as capillary electrophoresis assays, we selected aptamers with capacity to inhibit the enzymatic activity of PfPdxK. Our data constitute evidences about the application of SELEX technology in the rationale design of inhibitors against human malaria. (AU) | |
| FAPESP's process: | 11/19703-6 - Identification and interference with nutrient transporters integrated to erythrocyte surface by the Human Malaria parasite: Plasmodium falciparum |
| Grantee: | Flávia Menezes Zimbres |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |