Immunization with PfGBP130 generates antibodies that inhibit RBC invasion by P. falciparum parasites

Front Immunol. 2024 May 28:15:1350560. doi: 10.3389/fimmu.2024.1350560. eCollection 2024.

Abstract

Background: Despite decades of effort, Plasmodium falciparum malaria remains a leading killer of children. The absence of a highly effective vaccine and the emergence of parasites resistant to both diagnosis as well as treatment hamper effective public health interventions.

Methods and results: To discover new vaccine candidates, we used our whole proteome differential screening method and identified PfGBP130 as a parasite protein uniquely recognized by antibodies from children who had developed resistance to P. falciparum infection but not from those who remained susceptible. We formulated PfGBP130 as lipid encapsulated mRNA, DNA plasmid, and recombinant protein-based immunogens and evaluated the efficacy of murine polyclonal anti-PfGBP130 antisera to inhibit parasite growth in vitro. Immunization of mice with PfGBP130-A (aa 111-374), the region identified in our differential screen, formulated as a DNA plasmid or lipid encapsulated mRNA, but not as a recombinant protein, induced antibodies that inhibited RBC invasion in vitro. mRNA encoding the full ectodomain of PfGBP130 (aa 89-824) also generated parasite growth-inhibitory antibodies.

Conclusion: We are currently advancing PfGBP130-A formulated as a lipid-encapsulated mRNA for efficacy evaluation in non-human primates.

Keywords: Plasmodium falciparum; blood stage malaria antigen; growth inhibiting activity; mRNA; malaria; vaccine.

MeSH terms

  • Animals
  • Antibodies, Protozoan* / immunology
  • Antigens, Protozoan / immunology
  • Erythrocytes* / immunology
  • Erythrocytes* / parasitology
  • Female
  • Humans
  • Immunization
  • Malaria Vaccines* / immunology
  • Malaria, Falciparum* / immunology
  • Malaria, Falciparum* / prevention & control
  • Mice
  • Plasmodium falciparum* / immunology
  • Protozoan Proteins* / genetics
  • Protozoan Proteins* / immunology

Substances

  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Malaria Vaccines
  • Protozoan Proteins

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. Identification and characterization of PfGBP130 was supported by NIH R01 AI110699, 1R01 AI127699, 1R01 AI076353 and 1R56AI173140 to JDK and R01AI144014 and USF startup funds to DR.