Get Genetically Manipulated Malaria Parasite Information Form - Mr4

Malaria in humans is caused by six Plasmodium species: Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, Plasmodium ovale curtisi, P. ovale wallikeri and Plasmodium knowlesi which, although zoonotic, is an important pathogen in humans in several regions of South East Asia [1, 2].

In the case of malaria in man, however, considerable genetic resistance is known to be conferred by two major genes, the sickle-cell gene and the glucosed-phos- phate dehydrogenase-deficiency gene; there is also strong circumstantial evi- dence that the same is true of other abnormal hemoglobin genes.

To create their experimental vaccine, the researchers deleted three genes in the pathogen that causes malaria, Plasmodium falciparum. These genes are critical to the parasites' ability to establish the early stages of infection.

Sure enough, the gene-edited mosquitos produced malaria-fighting antibodies. Those antibodies "worked very well," says James. "They reduce the number of parasites in the mosquito, most importantly in the salivary gland, which is where they would be before they were transmitted to a human host."

Four kinds of malaria parasites infect humans: Plasmodium falciparum, P. vivax, P. ovale, and P. malariae. In addition, P. knowlesi, a type of malaria that naturally infects macaques in Southeast Asia, also infects humans, causing malaria that is transmitted from animal to human (“zoonotic” malaria).

Transgenic parasites combined with in vivo pre-clinical testing models (e.g. mice) are used to evaluate vaccine safety, potency and the durability of protection as well as to uncover critical protective immune responses and to refine vaccination strategies.

To quantify malaria parasites against WBCs: on the thick smear, tally the parasites against WBCs, until you have counted 500 parasites or 1,000 WBCs, whichever comes first; express the results as parasites per microliter of blood, using the WBC count if known, or otherwise assuming 8,000 WBCs per microliter blood.

Malaria vaccines have been in development for almost 60 years. The RTS,S/AS01 vaccine has now been approved, but cannot be a stand-alone solution. Development should continue on promising candidates such as R21, PfSPZ and P. vivax vaccines.