Unit: Center for the Production and Infection of Anopheles
Director: Bourgouin Catherine
The plateform CEPIA has mass-produced three Anopheles species (gambiae, stephensi et albimanus). More than 200 000 female mosquitoes were provided to research groups involved in mosquito-Plasmodium-vertebrate hosts interactions, mostly within the GPH Anopheles program. The in vitro production of P. falciparum gametocytes using an automatized system became operational in 2004. In addition, expertise was provided to implement the RNAi technology for functional genomics in A. gambiae.
The CEPIA, CEnter for the Production and Infection of Anopheles, is a plateform the objectives and missions of which are organised around three main activities :
the production for the benefit of diverse research programs and teams, of Anopheles mosquitoes that are natural hosts and vectors or laboratory hosts for diverse Plasmodium species,
providing lab facilities, equipement and expertise for the research teams in order to:
perform mosquito infection by rodent malaria parasites,
perform mosquito dissections or manipulations
set up fonctional genomic studies in Anopheles, using tools such as transgenesis and RNAi
the development of collaborative projects that require Anopheles mosquitoes
The plateform is also investing in producing P. falciparum gametocytes and in infecting Anopheles with this parasite species.
Activity in 2004 :
1) Mass production of Anopheles mosquitoes :
An. gambiae, An. stephensi and An. albimanus have been mass produced and distributed to 6 research Units within the Pasteur Institute (Biochimie et Biologie Moléculaire des Insectes, Biologie et Génétique du Paludisme, Immunophysiopathologie infectieuse, Réponses précoces aux Parasites et Immunopathologie, Génétique de la Différenciation, Parasitologie Biomédicale) and to a limited extent to teams oustide the Institute. The number of mosquitoes provided during 2004 has increased slightly compared to that provided in 2003. (Figure 1). The previsions for 2005 already show a large increase in the requests for mosquitoes. The new facilities in the building Rue des Volontaires, which just opened in December 2004, will allow to increase the capacity of production and should enable the CEPIA to fullfil the demands.
2) Quality control
To avoid cross-contamination between species that are produced in very large quantities, a quality control assessment has been set up. This control makes use of differences in the patterns of the mosquito wings between species (Figure). In addition, the receptivity of mosquitoes to the development of Plasmodium is surveyed throughout the year. Figure 3 displays the receptivity of An. stephensi to P. berghei from January to September 2004. This graph was deduced from our data base that collects information from the teams using mosquitoes produced by the CEPIA.
3) Production of Plasmodium falciparum gametocytes. Experimental infection of Anopheles with P. falciparum
The ability to infect Anopheles mosquitoes with the human malaria parasite P.falciparum has two main goals :
first to facilitate molecular and cellular analyses of the interaction between the human parasite and a natural host and vector (An. gambiae), secondly to produce sporozoites, the parasite stage present in the mosquito salivary glands that initiates the early phase of the infection in the vertebrate host. Only the erythocytic development of the human malaria parasite is mastered in vitro. Therefore, the production of sporozoites through its mosquito host is required for any project aimed at understanding the biological processes (cellular, immunological) leading to the development of the sporozoites in humans.
Using an automated system for culturing, gametocytes from strain NF54 is now produced on a regular basis. The experimental conditions for infecting Anopheles have not yet reached their optimum.
4) Research programs
The CEPIA is an essential partner for the GPH Anophèles (Grand Programme Horizontal) started in 2002 Sept. Beside the production of mosquitoes, the CEPIA participates in the development of tools for functional genomics (transgenesis and RNAi)
The CEPIA is also participating in two other research programs developped at the IMTSSA (Dr C. Rogier) and the Paris University Pierre & Marie Curie (L. Lambrechts-J. Koella).