News & Topics
Research
2010.01.21
Immunogenicity of Whole-Parasite Vaccines against Plasmodium falciparum Involves Malarial Hemozoin and Host TLR9 (Coban 准教授がCell Host & Microbe に掲載)
免疫学フロンティア研究センターのCoban 准教授の論文がCell Host & Microbe に掲載されました。
Article
"Immunogenicity of Whole-Parasite Vaccines against Plasmodium falciparum Involves Malarial Hemozoin and Host TLR9"
Pre. Review<
"Hemozoin: Malaria's Built-InAdjuvant and TLR9 Agonist"
While whole-parasite vaccine strategies for malaria infection have regained attention, although their immunological mechanisms of action remain unclear. We found in this study that:
- Crude extract from blood stages of P. falciparum is effective as a whole blood-stage parasite vaccine via TLR9.
- The malarial heme-detoxification byproduct, hemozoin, but not malarial DNA, acts as a 'built-in' adjuvant.
- Both synthetic and natural hemozoin bind directly to TLR9 and induce conformational changes in the receptor.
- The adjuvant effect of synthetic hemozoin depends on its method of synthesis and particle size.
- Natural and synthetic hemozoin use different receptors for their adjuvant effect
- The adjuvant function of synthetic hemozoin was further validated in a canine anti-allergen vaccine and malaria vaccine models. Hemozoin, both in synthetic and native form, can influence adaptive immune responses to malaria infection, and may have therapeutic value in vaccine adjuvant development.