JAN 18, 2017 4:23 PM PST

Malaria Vaccine Developed by Using Genetic Modifications

WRITTEN BY: Carmen Leitch

Malaria has been a global health problem for ages; it comes from a parasite that is over 130 million years old and is referenced as early as 2700 BC.  Researchers may have found some real success in combating the problem at its root, rather than through symptom treatment. A clinical trial using human subjects showed that a new vaccine was safe to use and tolerated by people, and it was effective in inducing the necessary immune response. The work, performed by researchers at the Center for Infectious Disease Research (CIDR) and Fred Hutchinson Cancer Research Center, was reported in Science Translational Medicine. It's discussed in part of the following video, starting at around the second minute.

The researchers utilized a malaria parasite that had been weakened by removing three genes that are required for the pathogenicity of the parasite. The so-called genetically attenuated parasites, GAPs, are unable to reproduce in the human liver. The immune system still builds up an immunity to malaria through the parasite because they remain alive. This is the first use of a genetically attenuated parasite, instead of attenuation by other means, and it has produced success where other methods have failed.

"This most recent publication builds on our previous work," said the GAP project leader, Sebastian Mikolajczak, Ph.D., a CIDR Principal Scientist. "We had already good indicators in preclinical studies that this new 'triple knock-out' GAP (GAP3KO), which has three genes removed, is completely attenuated. The clinical study now shows that the GAP3KO vaccine is completely attenuated in humans and also shows that even after only a single administration, it elicits a robust immune response against the malaria parasite. Together these findings are critical milestones for malaria vaccine development.”

"This report is a major advance in malaria vaccine development by providing the first evidence that genetically attenuated Plasmodium falciparum parasites are safe and immunogenic in humans," commented Robert Seder, M.D., Chief of Cellular Immunology at the Vaccine Research Center of the National Institutes of Health, who was not involved in this work. "Future studies demonstrating protective efficacy will be the next critical milestone for continued development of this promising vaccine approach.”

The GAP3KO project was completed at the CIDR Human Challenge Center,  a part of the Seattle Malaria Clinical Trials Center, an inter-institutional collaboration that works to fight malaria through drug and vaccine development. 

"We are very fortunate to have the human malaria challenge model to take the critical next step evaluating the efficacy of GAP3KO in preventing malaria in people," said Fred Hutch scientist James Kublin, M.D., M.P.H., the Medical Director of the Seattle MCTC. "The Hutch is looking forward to bringing its expertise in clinical trial design and management to the next stage of tests for this vaccine. The collaborations we have with CIDR and other nearby institutions is what makes Seattle a world leader in the malaria vaccine development and the human challenge model."

Malaria causes over 200 million infections, killing almost half a million people in 2015 alone. This new candidate could be a major step forward for regions plagued by the parasite.

 

Sources: AAAS/Eurekalert! via Fearey Group, Malaria.com, Science Translational Medicine

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
AUG 24, 2020
Immunology
Injectable Drug Stops HIV From Entering Cells
AUG 24, 2020
Injectable Drug Stops HIV From Entering Cells
Once in the body, HIV tracks down T cells that bear the CD4 receptor. It attaches to these immune cells, fusing itself w ...
SEP 14, 2020
Microbiology
The Immune System Can Kill HIV with a Helper Molecule
SEP 14, 2020
The Immune System Can Kill HIV with a Helper Molecule
HIV attacks the human immune system's CD4 cells, a major player in the body's defense against pathogens.
NOV 05, 2020
Clinical & Molecular DX
Painless Microneedle Patch Diagnoses Malaria in Minutes
NOV 05, 2020
Painless Microneedle Patch Diagnoses Malaria in Minutes
It looks like a Band-Aid — a small, adhesive patch that is applied directly to the skin. This simple, low-cost dia ...
NOV 09, 2020
Microbiology
Fighting COVID-19 with Help From Llamas
NOV 09, 2020
Fighting COVID-19 with Help From Llamas
Camelids, which include llamas, alpacas and camels have immune systems that generate two kinds of antibodies when confro ...
NOV 10, 2020
Microbiology
New Species of Rocky Mountain Spotted Fever-Causing Bacteria is IDed
NOV 10, 2020
New Species of Rocky Mountain Spotted Fever-Causing Bacteria is IDed
Ticks transmit the bacterial pathogen that causes Rocky Mountain Spotted Fever (RMSF).
NOV 10, 2020
Neuroscience
Nanoparticles Pass the Blood-Brain Barrier in Zebrafish
NOV 10, 2020
Nanoparticles Pass the Blood-Brain Barrier in Zebrafish
Video:  Explains the challenges of delivering medicine to the brain, and possibly tools to pass the blood-brain bar ...
Loading Comments...