Plasmodium berghei

Plasmodium berghei is a species in the genus "Plasmodium" subgenus "Vinckeia".
It is a protozoan parasite that causes malaria in certain rodents. Originally, isolated from thicket rats in Central Africa, "P. berghei" is one of four "Plasmodium" species that have been described in African murine rodents, the others being "Plasmodium chabaudi", "Plasmodium vinckei", and "Plasmodium yoelii". Due to its ability to infect rodents and relative ease of genetic engineering, "P. berghei" is a popular model organism for the study of human malaria.
Biology.
Like all malaria parasites of mammals, including the four human malaria parasites, "P. berghei" is transmitted by "Anopheles" mosquitoes and it infects the liver after being injected into the bloodstream by a bite of an infected female mosquito. After a short period (a few days) of development and multiplication, these parasites leave the liver and invade erythrocytes (red blood cells). The multiplication of the parasite in the blood causes the pathology such as anaemia and damage of essential organs of the host such as lungs, liver, spleen. "P. berghei" infections may also affect the brain and can be the cause of cerebral complications in laboratory mice. These symptoms are to a certain degree comparable to symptoms of cerebral malaria in patients infected with the human malaria parasite "Plasmodium falciparum".
Distribution.
"Plasmodium berghei" is found in the forests of Central Africa, where its natural cyclic hosts are the thicket rat ("Grammomys surdaster") and the mosquito ("Anopheles dureni").
Hosts.
"Plasmodium berghei" was first identified in the thicket rat ("Grammomys surdaster"). It has also been described in "Leggada bella", "Praomys jacksoni" and "Thamnomys surdaster." In research laboratories, various rodents can be infected, such as mice, rats and gerbils ("Meriones unguiculatus").
The natural insect host of "P. berghei" is likely "Anopheles dureni", however in laboratory conditions it has also been shown to infect "Anopheles stephensi".
History.
This species was first described by Vincke and Lips in 1948 in the Belgian Congo.
Research.
"Plasmodium berghei" infection of laboratory mouse strains is frequently used in research as a model for human malaria. In the laboratory the natural hosts have been replaced by a number of commercially available laboratory mouse strains, and the mosquito "Anopheles stephensi", which is comparatively easily reared and maintained under defined laboratory conditions.
"Plasmodium berghei" is used as a model organism for the investigation of human malaria because of its similarity to the "Plasmodium" species which cause human malaria. "P. berghei" has a very similar life-cycle to the species that infect humans, and it causes disease in mice which has signs similar to those seen in human malaria. Importantly, "P. berghei" can be genetically manipulated more easily than the species which infect humans, making it a useful model for research into "Plasmodium" genetics.
In several aspects the pathology caused by "P. berghei" in mice differs from malaria caused by "P. falciparum" in humans. In particular, while death from "P. falciparum" malaria in humans is most frequently caused by the accumulation of red blood cells in the blood vessels of the brain, it is unclear to what extent this occurs in mice infected with "P. berghei". Instead, in "P. berghei" infection, mice are found to have an accumulation of immune cells in brain blood vessels. This has led some to question the use of "P. berghei" infections in mice as an appropriate model of cerebral malaria in humans.
"Plasmodium berghei" can be genetically manipulated in the laboratory using standard genetic engineering technologies. Consequently, this parasite is often used for the analysis of the function of malaria genes using the technology of genetic modification. Additionally, the genome of "P. berghei" has been sequenced and it shows a high similarity, both in structure and gene content, with the genome of the human malaria parasite "Plasmodium falciparum".
A number of genetically modified "P. berghei" lines have been generated which express fluorescent reporter proteins such as Green Fluorescent Protein (GFP) and mCherry (red) or bioluminescent reporters such as Luciferase. These transgenic parasites are important tools to study and visualize the parasites in the living host.
"P. berghei" is used in research programs for development and screening of anti-malarial drugs and for the development of an effective vaccine against malaria.