Malaria vaccine trial samples reveal immune benchmarks for achieving protection

May 13, 2020

By studying samples from two independent clinical trials of malaria vaccines, Gemma Moncunill and colleagues have linked signatures in the immune system to better vaccine protection from the disease in children and adults. Their analysis of the RTS,S vaccine and sporozoite immunization provides generalizable benchmarks that future studies could use to evaluate the effectiveness of malaria vaccine candidates. Malaria continues to pose a huge health burden around the world, with an estimated 218 million cases in 2018. The RTS,S vaccine is the only candidate to have advanced far into clinical trials, but it has shown only modest protection. Researchers have also tested alternative strategies; one approach that combines weakened malaria parasites with preventative drug treatment (CPS immunization) displayed 100% efficacy in experimental trials in adults. Nevertheless, the rollout of a malaria vaccine has been seriously impeded by limited knowledge of the mechanisms of immunity, as well as by a lack of immune surrogates that can predict vaccine efficacy. Using transcriptional analysis of immune cells and systems biology techniques, Moncunill et al. examined blood samples from 24 adult volunteers who received CPS immunization and 255 African children who participated in a phase 3 trial of the RTS,S vaccine. The authors made some surprising findings; for example, children who received the RTS,S vaccine showed few changes in gene expression compared with those who received a nonprotective vaccine. However, the team did identify sets of genes that were linked to a protective response in the trials, observing that the receptor TLR4 and the protein NF-κB both played an important role. Some individuals also showed pre-immunization signatures that were linked to protection, a finding that could help identify non-responders who may benefit from immune priming or other interventions before vaccination.
-end-


American Association for the Advancement of Science

Related Immune System Articles from Brightsurf:

How the immune system remembers viruses
For a person to acquire immunity to a disease, T cells must develop into memory cells after contact with the pathogen.

How does the immune system develop in the first days of life?
Researchers highlight the anti-inflammatory response taking place after birth and designed to shield the newborn from infection.

Memory training for the immune system
The immune system will memorize the pathogen after an infection and can therefore react promptly after reinfection with the same pathogen.

Immune system may have another job -- combatting depression
An inflammatory autoimmune response within the central nervous system similar to one linked to neurodegenerative diseases such as multiple sclerosis (MS) has also been found in the spinal fluid of healthy people, according to a new Yale-led study comparing immune system cells in the spinal fluid of MS patients and healthy subjects.

COVID-19: Immune system derails
Contrary to what has been generally assumed so far, a severe course of COVID-19 does not solely result in a strong immune reaction - rather, the immune response is caught in a continuous loop of activation and inhibition.

Immune cell steroids help tumours suppress the immune system, offering new drug targets
Tumours found to evade the immune system by telling immune cells to produce immunosuppressive steroids.

Immune system -- Knocked off balance
Instead of protecting us, the immune system can sometimes go awry, as in the case of autoimmune diseases and allergies.

Too much salt weakens the immune system
A high-salt diet is not only bad for one's blood pressure, but also for the immune system.

Parkinson's and the immune system
Mutations in the Parkin gene are a common cause of hereditary forms of Parkinson's disease.

How an immune system regulator shifts the balance of immune cells
Researchers have provided new insight on the role of cyclic AMP (cAMP) in regulating the immune response.

Read More: Immune System News and Immune System Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.