TY - JOUR
T1 - Creation and preclinical evaluation of genetically attenuated malaria parasites arresting growth late in the liver.
AU - Franke-Fayard, Blandine
AU - Marin-Mogollon, Catherin
AU - Geurten, Fiona J A
AU - Chevalley-Maurel, Séverine
AU - Ramesar, Jai
AU - Kroeze, Hans
AU - Baalbergen, Els
AU - Wessels, Els
AU - Baron, Ludivine
AU - Soulard, Valérie
AU - Martinson, Thomas
AU - Aleshnick, Maya
AU - Huijs, Antonius T G
AU - Subudhi, Amit
AU - Miyazaki, Yukiko
AU - Othman, Ahmad Syibli
AU - Kolli, Surendra Kumar
AU - Lamers, Olivia A C
AU - Roques, Magali
AU - Stanway, Rebecca R
AU - Murphy, Sean C
AU - Foquet, Lander
AU - Moita, Diana
AU - Mendes, António M
AU - Prudêncio, Miguel
AU - Dechering, Koen J
AU - Heussler, Volker T
AU - Pain, Arnab
AU - Wilder, Brandon K
AU - Roestenberg, Meta
AU - Janse, Chris J
N1 - KAUST Repository Item: Exported on 2022-12-12
Acknowledged KAUST grant number(s): BAS/1/1020-01-01
Acknowledgements: We acknowledge the critical contribution of the late Dr Shahid Khan to the design of these studies. We are grateful to Pr Jude Przyborski for the anti- P. falciparum EXP-1 antibody. This work was supported by LUMC internal funds. CM-M was, in part, supported by Colciencias Ph.D. fellowship (Call 568 from 2012 Resolution 01218 Bogotá, Colombia) and LUF project grant, Den Dulk-Moermans Fonds (grant reference number: W19374-2-32, 2019-2021). A.O. is supported by a Skim Latihan Akademik IPTA-SLAI (Ministry of Higher Education, Malaysia). A.P. acknowledges the Faculty Baseline funding (BAS/1/1020-01-01) from King Abdullah University of Science and Technology (KAUST).
PY - 2022/11/4
Y1 - 2022/11/4
N2 - Whole-sporozoite (WSp) malaria vaccines induce protective immune responses in animal malaria models and in humans. A recent clinical trial with a WSp vaccine comprising genetically attenuated parasites (GAP) which arrest growth early in the liver (PfSPZ-GA1), showed that GAPs can be safely administered to humans and immunogenicity is comparable to radiation-attenuated PfSPZ Vaccine. GAPs that arrest late in the liver stage (LA-GAP) have potential for increased potency as shown in rodent malaria models. Here we describe the generation of four putative P. falciparum LA-GAPs, generated by CRISPR/Cas9-mediated gene deletion. One out of four gene-deletion mutants produced sporozoites in sufficient numbers for further preclinical evaluation. This mutant, PfΔmei2, lacking the mei2-like RNA gene, showed late liver growth arrest in human liver-chimeric mice with human erythrocytes, absence of unwanted genetic alterations and sensitivity to antimalarial drugs. These features of PfΔmei2 make it a promising vaccine candidate, supporting further clinical evaluation. PfΔmei2 (GA2) has passed regulatory approval for safety and efficacy testing in humans based on the findings reported in this study.
AB - Whole-sporozoite (WSp) malaria vaccines induce protective immune responses in animal malaria models and in humans. A recent clinical trial with a WSp vaccine comprising genetically attenuated parasites (GAP) which arrest growth early in the liver (PfSPZ-GA1), showed that GAPs can be safely administered to humans and immunogenicity is comparable to radiation-attenuated PfSPZ Vaccine. GAPs that arrest late in the liver stage (LA-GAP) have potential for increased potency as shown in rodent malaria models. Here we describe the generation of four putative P. falciparum LA-GAPs, generated by CRISPR/Cas9-mediated gene deletion. One out of four gene-deletion mutants produced sporozoites in sufficient numbers for further preclinical evaluation. This mutant, PfΔmei2, lacking the mei2-like RNA gene, showed late liver growth arrest in human liver-chimeric mice with human erythrocytes, absence of unwanted genetic alterations and sensitivity to antimalarial drugs. These features of PfΔmei2 make it a promising vaccine candidate, supporting further clinical evaluation. PfΔmei2 (GA2) has passed regulatory approval for safety and efficacy testing in humans based on the findings reported in this study.
UR - http://hdl.handle.net/10754/685566
UR - https://www.nature.com/articles/s41541-022-00558-x
UR - http://www.scopus.com/inward/record.url?scp=85141373758&partnerID=8YFLogxK
U2 - 10.1038/s41541-022-00558-x
DO - 10.1038/s41541-022-00558-x
M3 - Article
C2 - 36333336
SN - 2059-0105
VL - 7
JO - npj Vaccines
JF - npj Vaccines
IS - 1
ER -