Progress in the Development of Subunit Vaccines against Malaria

Abstract

Malaria is a life-threatening disease and one of the main causes of morbidity and mortality in the human population. The disease also results in a major socio-economic burden. The rapid spread of malaria epidemics in developing countries is exacerbated by the rise in drug-resistant parasites and insecticide-resistant mosquitoes. At present, malaria research is focused mainly on the development of drugs with increased therapeutic effects against Plasmodium parasites. However, a vaccine against the disease is preferable over treatment to achieve long-term control. Trials to develop a safe and effective immunization protocol for the control of malaria have been occurring for decades, and continue on today; still, no effective vaccines are available on the market. Recently, peptide-based vaccines have become an attractive alternative approach. These vaccines utilize short protein fragments to induce immune responses against malaria parasites. Peptide-based vaccines are safer than traditional vaccines, relatively inexpensive to produce, and can be composed of multiple T- and B-cell epitopes integrated into one antigenic formulation. Various combinations, based on antigen choice, peptide epitope modification and delivery mechanism, have resulted in numerous potential malaria vaccines candidates; these are presently being studied in both preclinical and clinical trials. This review describes the current landscape of peptide-based vaccines, and addresses obstacles and opportunities in the production of malaria vaccines.

Progress in Parasite Genomics and Its Application to Current Challenges in Malaria Control

“…Liver surface antigen (LSA) is another pre-erythrocytic vaccine target. LSA is essential for the survival of the parasites during the late liver schizogony stage [105]. Schizonts are asexual stage of Plasmodium that developed from sporozoites and matured in infected hepatocytes.…”

“…PfLSA-1 is high conserved in P. falciparum and is found in parasitophorous vacuole in the liver stage of the parasites. PfLSA-1 contains 17 amino acids repeats and is associated with the late liver schizont stage [105,106]. LSA-1 can induce IgG and IgM antibodies as well as CD4+ T cell production [105,107].…”

“…PfLSA-1 contains 17 amino acids repeats and is associated with the late liver schizont stage [105,106]. LSA-1 can induce IgG and IgM antibodies as well as CD4+ T cell production [105,107]. LSA-1 vaccine is currently in phase I clinical trial and is still unclear its efficacy in humans.…”

“…LSA-3 appears to play a role in the parasitic growth in infected hepatocytes and erythrocytes [108]. A recent study indicated that LSA-3 provided full protect to chimpanzees from heterologous P. falciparum sporozoites [105]. Like LSA-1, LSA-3 is also in phase I clinical trial and its efficacy and immunogenicity in humans remain unclear.…”

Recent Advances in the Development of Protein- and Peptide-Based Subunit Vaccines against Tuberculosis

“…Overcoming the cold chain dependency is another advantage of the use of peptide-based vaccines. Besides, customizable design results in a reduced risk of harmful responses and side effects [ 48 , 68 , 69 ].…”