Plasmodium falciparum merozoite surface protein 3 as a vaccine candidate: a brief review

Despite the many efforts of researchers around the world, there is currently no effective vaccine for malaria. Numerous studies have been developed to find vaccine antigens that are immunogenic and safe. Among antigen candidates, Plasmodium falciparum merozoite surface protein 3 (MSP3) has stood out in a number of these studies for its ability to induce a consistent and protective immune response, also being safe for use in humans. This review presents the main studies that explored MSP3 as a vaccine candidate over the last few decades. MSP3 formulations were tested in animals and humans and the most advanced candidate formulations are MSP3-LSP, a combination of MSP3 and LSP1, and GMZ2 (a vaccine based on the recombinant protein fusion GLURP and MSP3) which is currently being tested in phase II clinical studies. This brief review highlights the history and the main formulations of MSP3-based vaccines approaches against P. falciparum

Circumsporozoite Surface Protein-based malaria vaccines: a review

Malaria represents a serious public health problem, presenting with high rates of incidence, morbidity and mortality in tropical and subtropical regions of the world. According to the World Health Organization, in 2018 there were 228 million cases and 405 thousand deaths caused by this disease in the world, affecting mainly children and pregnant women in Africa. Despite the programs carried out to control this disease, drug resistance and invertebrate vector resistance to insecticides have generated difficulties. An efficient vaccine against malaria would be a strategy with a high impact on the eradication and control of this disease. Researches aimed at developing vaccines have focused on antigens of high importance for the survival of the parasite such as the Circumsporozoite Surface Protein, involved in the pre-erythrocytic cycle during parasites invasion in hepatocytes. Currently, RTS’S is the most promising vaccine for malaria and was constructed using CSP; its performance was evaluated using two types of adjuvants: AS01 and AS02. The purpose of this review was to provide a bibliographic survey of historical researches that led to the development of RTS’S and its performance analysis over the decade. The search for new adjuvants to be associated with this antigen seems to be a way to obtain higher percentages of protection for a future malaria vaccine

Antibacterial activity of Minquartia guianensis extracts and phytochemical evaluation

The species Minquartia guianensis (Olacaceae) is found in the Amazon region and also in Nicarágua, Panamá and Costa Rica. Indigenous people from Ecuador use the bark infusion for intestinal infections treatment caused by parasites, against muscular pain and cutaneous irritations. For this reason, the aim of this work was to evaluate the antibacterial activity of M. guianensis extracts over Gram-negative (Shigella flexneri M90T, Salmonella choleraesuis 6958, Escherichia coli E2348/69) and Gram-positive bacteria (Methicillin-Resistant Staphylococcus aureus 33591, Methicillin-Sensible Staphylococcus aureus 25923, Bacillus cereus 9634, Bacillus liquefaciens clinical isolated). These bacteria are diarrhea related, which causes several child death in tropical regions. The active extract is under fractionation (leaf DCM) and until now, four triterpene were isolated lupeol, taraxerol, lupenona and squalene, but it was not possible yet to assay the substances, because of their small amount