Oregon Health & Science University scientists, working with an international team, say they have zeroed in on parasite fragments that might form the backbone of a universal, T cell-based malaria vaccine. The study, published Wednesday in Nature, highlights parasite peptides displayed by the immune molecule HLA-E that are conserved across species and visible to immune cells in the liver, where infection quietly sets up shop before symptoms hit.
According to Nature, the group used immunopeptidomics to pull out MHC-bound malaria peptides from infected cells and logged 453 unique peptides tied to 166 proteins, including many "housekeeping" antigens shared across the parasite’s life stages. The paper notes that identical peptides showed up on classical HLA-A, -B and -C alleles and on the non-classical HLA-E molecule, which matters because HLA-E is highly conserved in humans. Two of the antigens triggered protective CD8+ T cell immunity in rodent models.
How The Portland Team Showed The Targets Are In The Liver
Veterinary surgeons at OHSU’s Oregon National Primate Research Center developed a minimally invasive liver biopsy method that let the team confirm those same parasite fragments inside primate livers, not just in blood-stage samples. That helped connect what they saw in dishes and blood to the organ where the parasite first multiplies. As MedicalXpress reports, the researchers say they are already testing vaccine candidates built from this peptide catalog in animal models. “A T cell-based malaria vaccine has long been considered the field’s holy grail,” co-senior author Brandon Wilder said in the university release.
What A T-Cell Vaccine Could Change
Today’s leading malaria vaccines focus on antibodies. They can cut cases in children but often need repeated booster doses to keep immunity up. A successful T cell-based shot could instead seek out and destroy infected liver cells, with the potential for sturdier, longer-lasting protection.
All of this is playing out against a stark backdrop. The World Health Organization estimates about 282 million malaria cases and 610,000 deaths worldwide in 2024, a reminder of why scientists are chasing tools that can work across multiple parasite species and life stages.
What Comes Next From The Portland Lab
OHSU and its collaborators say their peptide list offers a concrete blueprint for vaccine design, and preclinical testing has already started. The university notes that the Wilder lab has foundation backing for related projects, and press coverage of the release has pointed to a two-year Gates Foundation award last year to assess antibody and vaccine candidates.
As OHSU cautions, though, turning promising lab data into human trials will require extensive safety and efficacy work, and getting to a licensed vaccine will not be quick. For Portland researchers and global health watchers, this is a significant step forward and a rare roadmap to targets conserved across species and stages, but the journey from the pages of Nature to a widely available shot will play out over years, not months.
