Malaria is a disease that is caused by infection with parasites of the Plasmodium species. In Africa, it is commonly caused by Plasmodium falciparum. Infection results in a clinical disease that could be mild and easily treatable or end up in severe disability and death.
Fortunately, adults can become resistant to the severe illness that threatens the life of young children. One way in which they do this is by making antibodies against the parasite. Early studies showed that these antibodies could treat parasites, just as well as drugs.
However, the parasite is complex and contains thousands of proteins, many of which keep changing all the time. SMART aims to identify WHICH of these proteins help adults to make “good” antibodies that actually eliminate malaria parasites. We do this by analysing samples from people infected with malaria in different parts of the African continent.
To help us identify “good” antibodies that kill malaria parasites, we chose a selection of proteins that were likely targets for antibodies. We made laboratory versions of these proteins and stuck them onto a glass slide (chip). We use this chip to analyse samples from people infected with malaria. Our chip is among the first of its kind in Africa, and it allows us to analyze thousands of samples in a short time.
Rinter Kimathi prepares microarray printer for run
Our SMART-EDCTP project aims to understand how we can overcome the fact that many of the parasites proteins that we consider for vaccination change all the time. Can we find parts of these proteins that do not change? Can we define the equivalent of a mosaic that would represent all possible changes of a given set of proteins?
To do this we are analyzing parasites collected in our participating countries. For selected proteins of interest, we are working to understand how to stay ahead of the parasite with regards to its continuous changes. This information is vital for making a vaccine that will work for everyone, and simultaneously outwit the parasite.
Tim Chege thoughtfully acquiring data
In the Control of Parasitaemia (COP) project we want to focus on adults. Adults have the “magic” with regards to keeping malaria at bay. They get infected, but are able to keep the parasite under check, not succumbing to clinical disease. How do they do this? We await a funding decision to help us find out.
CHMI-SIKA brings together multiple partners working together using a malaria challenge model. Under carefully controlled conditions, and with all ethical permissions, humans are infected with Plasmodium falciparum. Concurrently, we study their immune responses. This is a powerful way to determine which immune responses are important for controlling malaria.
Walter Reed Tanzania
In this project, we aim to use our chip to identify responses that would help army personnel identify which soldiers are at risk of developing malaria when deployed to malaria-infested areas as part of their duties. This would allow focusing of resources on individuals that really need it and in so doing delay the spread of drug resistance.
During my PhD project I discovered new proteins from the malaria parasite that might be good for malaria vaccines. I am exploring their vaccination potential in more detail during my Postdoc.
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