Abstract: Disclosed is a method of screening a test substance for possession of binding activity for possession of binding activity for MSP42 or a fragment thereof, the method comprising the steps of: combining or contacting, in any order, (i) a molecule comprising MSP142 or a fragment thereof, (ii) the test substance, and (iii) a comparison substance known to have binding activity for MSP142 or a fragment thereof; and determining the presence and/or amount, if any, of comparison substance and/or test substance bound of the MSP142 or fragment thereof.

Abstract: A non-naturally occurring variant of a C-terminal fragment of a Plasmodium merozoite surface protein-1 (MSP-1) wherein said variant has (i) a reduced affinity, compared with a naturally occurring Plasmodium MSP-119, for at least one first antibody capable of blocking the binding of a second antibody, which second antibody inhibits the proteolytic cleavage of Plasmodium MSP-142 and (ii) substantially the same affinity for at least one third antibody compared with said naturally occurring Plasmodium MSP-119. which third antibody inhibits the proteolytic cleavage of Plasmodium MSP-142 is provided for use in an anti-malarial vaccine.

Abstract: A non-naturally occurring variant of a C-terminal fragment of a Plasmodium merozoite surface protein-1 (MSP-1) wherein said variant has (i) a reduced affinity, compared with a naturally occurring Plasmodium MSP-119, for at least one first antibody capable of blocking the binding of a second antibody, which second antibody inhibits the proteolytic cleavage of Plasmodium MSP-142 and (ii) substantially the same affinity for at least one third antibody compared with said naturally occurring Plasmodium MSP-119. which third antibody inhibits the proteolytic cleavage of Plasmodium MSP-142 is provided for use in an anti-malarial vaccine.

Abstract: Disclosed are novel polypeptides comprising the sequences substantially as shown in FIGS. 1 and 2, in isolation from sequences naturally occuring adjacent thereto in the merozoide suface protein MSP1. Also disclosed are vectors comprising nucleotide sequences encoding said polypeptides, host cells comprising said vectors and a vaccine comprising one or both novel polypeptides.

Abstract: The present invention relates to the P.195 gene of Plasmodium falciparum and, more specifically, to the cloning of that gene. The invention further relates to a method of producing the P.195 protein using the cloned gene. The invention also relates to a vaccine comprising the P.195 protein and to the use of same in the prophylaxis of malaria.

Abstract: Protection inducing antigens or parasites of the genus Plasmodium are described. The antigens have an apparent molecular weight of 1.8 to 2.5.times.10.sup.5 and are associated with the membranes of the erythrocytic schizont forms of the parasite. The antigens may be incorporated into vaccines and used for the inducing of immunity into susceptible vetebrate hosts including humans. Methods for the preparation of the antigens are also described.