Vaccination of rhesus monkeys against Plasmodium knowlesi with aqueous suspension of MDP as an adjuvant.

In these investigations two types of antigen preparations were used: (i) Whole Antigen (WAg), and (ii) Soluble Antigen (SAg). For immunization, Muramyl Dipeptide (MDP) was employed as an adjuvant. Highest reciprocal antibody titre values were recorded in ELISA and IHA tests from animals immunized by WAg-MDP. Skin reactions in animals sensitized with WAg-MDP combination showed a well developed zone of erythema with induration after 24 hours of intradermal injection. Animals immunized with WAg-MDP showed a maximum leukocyte migration inhibition. All the animals in experimental and control groups showed patent infection following challenge with live parasites. Animals belonging to the control groups showed 100% mortality. On the basis of these experiments it could be concluded that MDP preparation afforded some protection to the test animals.