Newly described human antibody prevents malaria in mice

March 19, 2018, NIH/National Institute of Allergy and Infectious Diseases
The malaria sporozoites, the infectious form of the malaria parasite. Credit: NIAID

Scientists have discovered a human antibody that protected mice from infection with the deadliest malaria parasite, Plasmodium falciparum. The research findings provide the basis for future testing in humans to determine if the antibody can provide short-term protection against malaria, and also may aid in vaccine design. Investigators at the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, led the research with colleagues at the Fred Hutchinson Cancer Research Center in Seattle. Currently, there is no highly effective, long-lasting vaccine to prevent malaria, a mosquito-spread disease that causes some 430,000 deaths each year, primarily among young children in sub-Saharan Africa.

The research team isolated the antibody, called CIS43, from the blood of a volunteer who had received an experimental vaccine made from whole, weakened parasites (PfSPZ Vaccine-Sanaria). The volunteer was later exposed to infectious malaria-carrying mosquitoes under carefully controlled conditions and did not become infected. In two different models of malaria in mice, CIS43 was highly effective at preventing malaria infection. If confirmed through additional studies in people, CIS43 could be developed as a prophylactic measure to prevent infection for several months after administration, the researchers say. Such a prophylactic antibody could be useful for tourists, health care workers, military personnel or others who travel to areas where malaria is common. Moreover, if the antibody prevented malaria infection for up to six months, it might be combined with antimalarial drugs and be deployed as part of mass drug administration efforts that potentially could eliminate the disease in malaria-endemic regions.

Detailed examination of CIS43 revealed that it works by binding to a specific portion (epitope) of a key parasite surface protein. This epitope occurs only once along the length of the surface protein. In addition, the CIS43-binding epitope is conserved across 99.8 percent of all known strains of P. falciparum, making it an attractive target for next-generation experimental malaria vaccines designed to elicit production of this neutralizing antibody.

Researchers at the NIAID Vaccine Research Center are planning to assess the safety and protective efficacy of the newly described CIS43 antibody next year in controlled human challenge trials.

Additional collaborators on the study included scientists at the Johns Hopkins Bloomberg School of Public Health in Baltimore, the Seattle Biomedical Research Institute and Sanaria Inc., Rockville, Maryland.

The study is published in Nature Medicine.

Explore further: Modified experimental vaccine protects monkeys from deadly malaria

More information: A human monoclonal antibody prevents malaria infection by targeting a new site of vulnerability on the parasite, Nature Medicine, nature.com/articles/doi:10.1038/nm.4512

Related Stories

Modified experimental vaccine protects monkeys from deadly malaria

May 22, 2017
Researchers from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, modified an experimental malaria vaccine and showed that it completely protected four of eight ...

Experimental vaccine protects against multiple malaria strains

February 20, 2017
An experimental malaria vaccine protected healthy subjects from infection with a malaria strain different from that contained in the vaccine, according to a study published today in the Proceedings of the National Academy ...

Human antibodies undermine parasite sex

February 8, 2018
Some people develop an immune response following a malaria infection that stops them from infecting other mosquitoes. The antibodies that these people produce are ingested by the mosquito and destroy the malaria parasite ...

New study finds that malaria vaccine protects adults for up to a year

May 9, 2016
Malaria infects hundreds of millions of people every year, and kills more than half a million, most of them under the age of 5 years. There is no vaccine.

Discovery of key molecules involved in severe malaria – new target for malaria vaccine

December 4, 2017
Malaria is one of three major infectious diseases affecting approximately 300 million people every year, accounting for about 500,000 deaths, but effective vaccine development has not been successful. Among malaria parasites ...

Vaccine made from complex of two malaria proteins protects mice from lethal infection

June 23, 2014
An experimental vaccine designed to spur production of antibodies against a key malaria parasite protein, AMA1, was developed more than decade ago by scientists from the National Institute of Allergy and Infectious Diseases ...

Recommended for you

Cancer drug helps treat tuberculosis by restoring leaky blood vessels

April 26, 2018
Biomedical engineers have discovered an unlikely potential ally in the global fight against tuberculosis—an FDA-approved drug originally designed to treat cancer.

Molecule may help tame virulent bacteria and prevent infection

April 26, 2018
According to the U.S. Centers for Disease Control and Prevention, about one in three humans carries Staphylococcus aureus, or "staph," in our noses, and 2 percent of us carry the dreaded methicillin-resistant (MRSA) strain ...

Antibody 'cocktail' can prevent Zika infection but is not effective for treatment of fetuses

April 26, 2018
A "cocktail" of monoclonal antibodies that can prevent Zika virus (ZIKV) infection in primates was not effective for treatment of fetuses, according to a new collaborative study led by a University of Miami Miller School ...

E. coli—are we measuring the wrong thing?

April 25, 2018
A sepsis awareness and management programme has demonstrated overall success in terms of improved sepsis detection, but has led to an increase in the number of E. coli blood stream infection cases presented, calling into ...

Malaria study reveals gene variants linked to risk of disease

April 25, 2018
Many people of African heritage are protected against malaria by inheriting a particular version of a gene, a large-scale study has shown.

Commonly prescribed heartburn drug linked to pneumonia in older adults

April 24, 2018
Researchers at the University of Exeter have found a statistical link between pneumonia in older people and a group of medicines commonly used to neutralise stomach acid in people with heartburn or stomach ulcers. Although ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.