Original Article

Potential of RH5 Antisense on Plasmodium falciparum Proliferation Abatement


Background: Infections by Plasmodium falciparum, are becoming increasingly difficult to treat. Therefore, there is an urgent need for novel antimalarial agents’ discovery against infection. In present study, we described a 2’-O-Methyl gapmer phosphorothioate oligonucleotide antisense targeting translation initiation region of 3D7 strain RH5 gene.

Methods: The study was conducted in Pasteur Institute of Iran in 2020. ODNs effects were measured by microscopic examination and real time RT-PCR. For microscopy, microplates were charged with 2’-OMe ODNs at different dilutions. Unsynchronized parasites were added to a total of 0.4 ml (0.4% parasitemia, 5% red blood cells), and slides were prepared. Proportion of infected cells was measured by counting at least 500 red blood cells.

Results: RH5 genes start codon regions selected as conserved region besed on alignment results. Gap-RH5-As which was complementary to sequence surrounding AUG RH5 start codon significantly reduced parasite growth (>90% at 50 nM) compared to sense sequence control (Gap-RH5-Se) (17%), (P<0.001). RH5 transcripts were dramatically reduced after exposed to ODNs at a concentration of 5-500 nM for 48 h.

Conclusion: Gemnosis delivery of a chimeric gapmer PS-ODN with 2’-OMe modifications at both sides had high antisense activity at low concentrations (10-100 nM) and shown a good efficiency to reach to target mRNA in human RBCs. Anti-parasite effect was correlated to reduction of target gene mRNA level. In addition, 2’-OMe ODNs free delivery is an effective way and does not need any carrier molecules or particles.

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IssueVol 17 No 4 (2022) QRcode
SectionOriginal Article(s)
DOI https://doi.org/10.18502/ijpa.v17i4.11280
Antisense Plasmodium falciparum Malaria

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How to Cite
Razavi Vakhshourpour S, Nateghpour M, Shahrokhi N, Motevalli Haghi A, Mohebali M, Hanifian H. Potential of RH5 Antisense on Plasmodium falciparum Proliferation Abatement. Iran J Parasitol. 2022;17(4):525-534.