| Successful modification | The parasite was generated by the genetic modification |
| The mutant contains the following genetic modification(s) |
Gene mutation
|
| Reference (PubMed-PMID number) |
Reference 1 (PMID number) : 34252120
|
| MR4 number |
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| Parent parasite used to introduce the genetic modification |
| Rodent Malaria Parasite | P. berghei |
| Parent strain/line | P. berghei ANKA |
| Name parent line/clone |
RMgm-932
|
| Other information parent line | GIMO-PbANKA (RMgm-932, 1309cl1) contains as a selectable marker (SM) the fusion gene of hdhfr (human dihydrofolate reductase; positive SM) and yfcu (yeast cytosine deaminase and uridyl phosphoribosyl transferase; negative SM) stably integrated into the b9 locus (PBANKA_0808100) through double cross-over recombination. The SM is under control of the P. berghei eef1α promoter. |
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| The mutant parasite was generated by |
| Name PI/Researcher | Kolli SK, Salman AM, Hill AVS, Janse CJ |
| Name Group/Department | Malaria research group, Department of Parasitology |
| Name Institute | Leiden University Medical Center, LUMC |
| City | Leiden |
| Country | The Netherlands |
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| Name of the mutant parasite |
| RMgm number | RMgm-4917 |
| Principal name | 2355cl1 |
| Alternative name | |
| Standardized name | |
| Is the mutant parasite cloned after genetic modification | Yes |
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| Phenotype |
| Asexual blood stage | Not different from wild type |
| Gametocyte/Gamete | Not different from wild type |
| Fertilization and ookinete | Not different from wild type |
| Oocyst | Not different from wild type |
| Sporozoite | Normal numbers of sporozoites; P. falciparum transgene expression in sporozoites; sporozoites have reduced infectivity (as shown by reduced or absence of parasite liver loads after intravenous injection of sporozoites and absence of blood-stage infection or prolonged prepatent period) |
| Liver stage | Sporozoites have reduced infectivity (as shown by reduced or absence of parasite liver loads after intravenous injection of sporozoites and absence of blood-stage infection or prolonged prepatent period) |
| Additional remarks phenotype | Mutant/mutation
The mutant expresses P. falciparum b9. The P. falciparum b9 gene is introduced into the endogenous P. berghei b9 gene locus (by GIMO transfection of line 1309cl1) and is under control of the Pb b9 regulatory 3'- and 5'-UTR sequences. It does not contain a drug selectable marker
The mutant has been generated and selected using the GIMO transfection method ('gene insertion/marker out') of transfection of a 'GIMO line' that contains the hdhfr::yfcu selectable marker into the b9 locus.
Protein (function)
Phenotype
Normal numbers of sporozoites; P. falciparum transgene expression in sporozoites; sporozoites have reduced infectivity (as shown by reduced or absence of parasite liver loads after intravenous injection of sporozoites and absence of blood-stage infection or prolonged prepatent period).
The failure to establish a liver infection like wild type parasites, indicates that expression of the P. falciparum protein in sporozoites has a negative impact of on sporozoite infectivity/establishment of a liver infection.
In this study 14 transgenic P. berghei parasites were generated that express P. falciparum proteins that are expressed in the sporozoite/liver stage of P. falciparum.
Six of these chimeric P. berghei parasites that produce infective sporozoites have been used in a challenge model to test the protective efficacy of novel P. falciparum viral vectored vaccine candidate antigens. Mice were immunized with the P. falciparum vaccine candidates, followed by challenge with the transgenic P. berghei sporozoites.
Expression of the P. falciparum antigens in the transgenic sporozoites was analysed by immunofluorescence assay (using serum from vaccinated mice)
Additional information
Other mutant
See the link for the other 14 transgenic P. berghei lines expressing P. falciparum proteins that were generated in this study |
*RMgm-4917
