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The TLR9 agonist CpG fails to enhance the acquisition of Plasmodium falciparum-specific memory B cells in semi-immune adults in Mali.

ABSTRACT: Antibodies play a key role in controlling blood stage malaria infections, and an effective blood stage malaria vaccine will likely require that it induce vaccine-specific memory B cells (MBCs). Our previous studies showed that the addition of the TLR9 agonist CpG to Plasmodium falciparum protein subunit vaccines greatly increased their efficacy in inducing MBCs in nonimmune U.S. volunteers. Here we show that in contrast the same CpG-containing malaria vaccine did not enhance the acquisition of MBCs in semi-immune adults living in Mali. Understanding the molecular basis of this apparent refractoriness to TLR9 agonist will be of significant interest in vaccine design.

SUBMITTER: Traore B

PROVIDER: S-EPMC2788035 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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The TLR9 agonist CpG fails to enhance the acquisition of Plasmodium falciparum-specific memory B cells in semi-immune adults in Mali.

Traore Boubacar B Koné Younoussou Y Doumbo Safiatou S Doumtabé Didier D Traoré Abdramane A Crompton Peter D PD Mircetic Marko M Huang Chiung-Yu CY Kayentao Kassoum K Dicko Alassane A Sagara Issaka I Ellis Ruth D RD Miura Kazutoyo K Guindo Agnes A Miller Louis H LH Doumbo Ogobara K OK Pierce Susan K SK

Vaccine 20090825 52

Antibodies play a key role in controlling blood stage malaria infections, and an effective blood stage malaria vaccine will likely require that it induce vaccine-specific memory B cells (MBCs). Our previous studies showed that the addition of the TLR9 agonist CpG to Plasmodium falciparum protein subunit vaccines greatly increased their efficacy in inducing MBCs in nonimmune U.S. volunteers. Here we show that in contrast the same CpG-containing malaria vaccine did not enhance the acquisition of M ...[more]

PMID: 19712767

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The TLR9 ligand CpG promotes the acquisition of Plasmodium falciparum-specific memory B cells in malaria-naive individuals.

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| S-EPMC2910392 | biostudies-literature

Nonagonistic Dectin-1 ligand transforms CpG into a multitask nanoparticulate TLR9 agonist.

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2016-03-17 | GSE79272 | GEO

Stimulation of isolated plasmacytoid dendritic cells (pDCs) with TLR9 agonist CpG C (CpG) and TLR7 agonist imiquimod (IMQ)

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The effect of TLR9 agonist CpG oligodeoxynucleotides on the intestinal immune response of cobia (Rachycentron canadum).

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| S-EPMC8560775 | biostudies-literature

A semi-synthetic glycosaminoglycan analogue inhibits and reverses Plasmodium falciparum cytoadherence.

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| S-EPMC5646806 | biostudies-literature

CD82 controls CpG-dependent TLR9 signaling.

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B Cells Produce Type 1 IFNs in Response to the TLR9 Agonist CpG-A Conjugated to Cationic Lipids.

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| S-EPMC5531204 | biostudies-literature

Ultra-sensitive RDT performance and antigen dynamics in a high-transmission Plasmodium falciparum setting in Mali.

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| S-EPMC7469912 | biostudies-literature

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