Evaluation of two long synthetic merozoite surface protein 2 peptides as malaria vaccine candidates

Vaccine. 2009 May 5;27(20):2653-61. doi: 10.1016/j.vaccine.2009.02.081. Epub 2009 Mar 6.

Abstract

Merozoite surface protein 2 (MSP2) is a promising vaccine candidate against Plasmodium falciparum blood stages. A recombinant 3D7 form of MSP2 was a subunit of Combination B, a blood stage vaccine tested in the field in Papua New Guinea. A selective effect in favour of the allelic family not represented by the vaccine argued for a MSP2 vaccine consisting of both dimorphic variants. An alternative approach to recombinant manufacture of vaccines is the production of long synthetic peptides (LSP). LSP exceeding a length of well over 100 amino acids can now be routinely synthesized. Synthetic production of vaccine antigens cuts the often time-consuming steps of protein expression and purification short. This considerably reduces the time for a candidate to reach the phase of clinical trials. Here we present the evaluation of two long synthetic peptides representing both allelic families of MSP2 as potential vaccine candidates. The constructs were well recognized by human immune sera from different locations and different age groups. Furthermore, peptide-specific antibodies in human immune sera were associated with protection from clinical malaria. The synthetic fragments share major antigenic properties with native MSP2. Immunization of mice with these antigens yielded high titre antibody responses and monoclonal antibodies recognized parasite-derived MSP2. Our results justify taking these candidate poly-peptides into further vaccine development.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / isolation & purification
  • Antibodies, Protozoan / blood
  • Antigens, Protozoan / immunology*
  • Child, Preschool
  • Female
  • Humans
  • Infant
  • Malaria Vaccines / chemical synthesis*
  • Malaria Vaccines / immunology*
  • Malaria, Falciparum / immunology
  • Male
  • Mice
  • Molecular Sequence Data
  • Plasmodium falciparum / immunology
  • Protozoan Proteins / chemical synthesis*
  • Protozoan Proteins / immunology*
  • Sequence Alignment
  • Vaccines, Synthetic / immunology
  • Young Adult

Substances

  • Antibodies, Monoclonal
  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Malaria Vaccines
  • Protozoan Proteins
  • Vaccines, Synthetic
  • merozoite surface protein 2, Plasmodium