My name is Francis Ndungu and I am from the KEMRI Wellcome Trust Programme in Kenya.
The Cellular Immunology Group includes scientists who are studying the human
the cells of the human immune system and the product that they make in order to understand
how people become immune to disease either following natural infection or immunisation.
So this group has got people who are working with HIV and other viruses, it's got people working
with malaria, and there are also people working with malnutrition. I am personally interested in
malaria and malaria vaccines and so my work includes understanding naturally acquired
immunity and picking whatever resonance we can learn from from it to develop a malaria vaccine.
So our platform for malaria immunology in Kilifi is based on two platforms:
one platform is conducting long-term longitudinal studies in children; and the other platform is
using experimental medicine where we infect people being exposed to malaria in order to identify
individuals who are immune to malaria so if we can identify people who are immune to malaria and then
we compare the immune responses to malaria with people who are not yet immune, then we
can identify immune responses that can be used to identify antigens that we can include in vaccines.
Another way that my work would help in developing malaria vaccines is helping in understanding why
it is so difficult to immunise people who live in endemic areas.
So one of the things that we've learned in the last few years is that if you develop a vaccine in Oxford or in America
and those vaccines actually tend to work quite well in animal models and in malaria-naïve individuals
but when you move them to malaria endemic areas they're not very immunogenic and
they're not as protective and so it appears like prior exposure to malaria modifies the
immune system making it more difficult to immunise people and my work is also trying to understand
what that modification is and how it can be counteracted in delivering an effective vaccine.
So one of the most exciting research projects that we've conducted in Kilifi recently is comparing
the immune response to malaria in individuals who are currently infected with malaria so people
who are living with constant infections these are people who are being persistently infected
or they have chronic infections and we also have another group of individuals who were exposed to
malaria a long time ago but they are no longer exposed to malaria because malaria has been
controlled in the area where they live so in other words it's like comparing malaria immune responses
to malaria in individuals who are currently living with malaria and individuals who were historically
infected a long time ago and what we found is that current exposure interferes or impairs the ability
of the cells in these individuals to respond to malaria antigens in the way we would expect.
So in the last five to ten years one of the great things that have happened of course is
that finders like the Wellcome Trust have decided to support experimental human medicine that is
for infections like malaria where it's easy to treat the disease then you can infect people who
are semi-immune to malaria in order to understand
immunity to malaria and that is one of the things that we're doing in Kenya at the moment,
and that is very exciting because the immuno-epidemiological studies are
happening in the field are confounded by many factors that make it hard to make conclusive
decisions on which immune responses or antigens that we can use for vaccines.
So other things that I have lines of investigation that have come up in the last five ten years is that
we've seen improvement in high-throughput technology for screening antigens that can
be included in vaccines and I think that is also quite good and also in the world of immunology
people have learned how to make human monoclonal antibodies and these human monoclonal antibodies
especially in the case of HIV also immunity and cancer
are actually being considered as therapeutics - immuno-therapeutics and in some cases also
infectious diseases we can use these monoclonal antibodies in the discovery for antigens that
could be used in vaccines and I think that is also quite exciting and in some cases the same
monoclonal antibodies can be used to block any undesirable immune responses that may
result in the immune response causing disease or interfering with immunisation.
I think it is really important for us to understand naturally acquired immunity to
malaria because as you know malaria continues to be a major public health issue in the countries
in Africa and in Southeast Asia and what we've seen in the last three years even though we have
effective drugs for treating malaria and insect sites for controlling malaria through
killing mosquitoes, is that the malaria control has stalled and so we need new tools to be
included together with the current tools to drive malaria transmission down further and my research
will inform the design and the development of new vaccines and other therapeutics.