Experimental infection and protection against ... - TI Pharma

Safety and Immunogenicity of a Recombinant Plasmodium falciparum AMA1
Malaria vaccine Adjuvanted with Alhydrogel TM, Montanide ISA 720 or AS02
Figure 5. Stimulation indices in response to 6 µg/ml PfAMA1 presented as box
plots and whiskers. Peripheral Blood Mononuclear Cells from immunised
volunteers 28 days after the second immunisation and 28 days after the third
immunisation (Day 56 and 84 respectively) were stimulated with 6 µg of
PfAMA1 vaccine. Cell proliferation was measured by adding 3H thymidine and
calculated relative to control wells. Box plots and whiskers show the range and
the 25th, 50th and 75th percentile. Circles represent outliers. Measurements
were performed at baseline, 28 days after the second immunisation and 28
days after the third immunisation (day 56 and 84 respectively).
Sera from vaccinees could be shown to recognise the native PfAMA1 by
immunofluorescence in a dose dependent manner. Eight of fifteen samples were
positive in IFA, amongst which were four samples with the highest antibody
titres. The staining pattern found in positive samples localised to the same
structures as 4G2 rat monoclonal antibody (Figure 3).
Cellular immune response
In all groups, induction of IFNγ and IL-5 cytokines could be demonstrated (Figure
4). The magnitude of cytokine production was not dose dependent or depen-
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