Desenvolvimento de um sistema em fluxo lateral para o diagnóstico de malária causada por Plasmodium falciparum

Abstract

Traditionally, confirmatory diagnosis of malaria is made by microscopic examination of blood. Therefore, the diagnosis of the disease may be complicated by the lack of people or equipment necessary to obtain a fast and reliable diagnosis, especially in areas of difficult access. For these and other reasons, rapid, practical and sensitive methods have been developed, such as immunochromatographic strips. Therefore, this work aimed to develop a lateral flow system for the diagnosis of malaria caused by Plasmodium falciparum. So, polyclonal and monoclonal antibodies against the protein HRP2 (Histidine rich protein 2) of Plasmodium falciparum were produced using a recombinant protein that it fused to a glutathione-S-transferase (rHRP2-GST, obtained in previous work). After hibridomas production, only 20 responded against the protein rHRP2-GST, and of these only four showed some react ivity against the native protein. The monoclonal antibody that reacted better on this last ELISA test and in an immunofluorescence was used on a lateral flow system standardized here. For this standardization, the system was first mounted in lateral flow competitive format followed by a sandwich system using polyclonal anti-rHRP2-GST. In assays using red blood cells parasitized by P. falciparum, positive results were obtained (detection of the infection in the immunochromatographic strip) using polyclonal antibodies. The system was stable within the test period, thus demonstrating that possibly in a controlled product ion environment, this lateral flow system could remain stable for a time suitable for marketing