| Pan-malarial antigens
Background:
Plasmodium aldolase (Paldolase) and plasmodium lactate dehydrogenase (PLDH) are part of glycolysis pathways in all malaria species. Since malaria parasites have specific forms, antibodies do not cross-react with human aldolase or LDH. Antibodies to these proteins may potentially recognise all species of malaria and are known as “pan-malaria specific antibodies”. These are:
- Plasmodium lactate dehydrogenase (PpanLDH)
- Plasmodium aldolase (Paldolase)
Use of Pan-malarial antifgens in RDT tests
Outside of Africa, the most frequently used form of malaria RDT combines a species-specific with a pan-species antibody e.g. HRP2/LDH or HRP2/aldolase
Use in malaria testing
Since pan-malarial antibody tests have the potential to detect any species of malaria they are attractive in diagnostic tests. However, thisusefulness is limited since although both offer good sensitivity for the recognition of ‘’P.falciparum’’ and ‘’P.vivax’’ they are less effective in the detection of other species (particularly at lower parasite concentrations).
Their use in combination tests is helpful when:
(1) A malarial species may be present that would not be detected by the species-specific antibody. The pan-malarial antibody may detect that species.
(2) If the species-specific antibody gives a false negative result (for example, gene deletion or prozone effect) then the pan-malarial antibody may still allow the infection to be detected.
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