Protective immunity against lethal anaphylactic reaction in Toxoplasma-infected mice by DNA vaccination with T. gondii-derived heat shock protein

Parasitol Int. 2010 Mar 23. [Epub ahead of print]

Protective immunity against lethal anaphylactic reaction in Toxoplasma gondii-infected mice by DNA vaccination with T. gondii-derived heat shock protein 70 gene

Kikumura A, Fang H, Mun HS, Uemura N, Makino M, Sayama Y, Norose K, Aosai F.

Department of Infection and Host Defense, Chiba University Graduate School of Medicine, 1-8-1 Inohana Chuo-ku, Chiba 260-8670, Japan.

Toxoplasma gondii-derived heat shock protein 70 (T.g.HSP70) was proven to induce lethal anaphylactic reaction in T. gondii-infected mice through platelet-activating factor (PAF)-mediated, but not classical IgE-dependent, pathway via TLR4/MyD88 signal pathway. The effector cells generating PAF and causing T.g.HSP70-induced anaphylactic reaction were CD11b(+) and CD11c(+) cells, although the reaction was enhanced by marked IFN-gamma production by CD11b(+), CD11c(+), CD4(+) and CD8(+) splenocytes. In the present study, the effects of T.g.HSP70 gene vaccine targeting peripheral dendritic cells were evaluated against T.g.HSP70-induced anaphylactic reaction in T. gondii-infected mice. C57BL/6 mice receiving T.g.HSP70 gene vaccine showed prolonged survival. Platelets of peripheral blood, which completely disappeared during the T.g.HSP70-induced anaphylactic reaction, were partially restored with the T.g.HSP70 gene vaccination. The T.g.HSP70-induced marked production of PAF and IFN-gamma from splenocytes of infected mice during the T.g.HSP70-induced anaphylactic reaction was shown to decrease after the T.g.HSP70 gene vaccination. Thus, T.g.HSP70 gene vaccine induced protective immunity against T.g.HSP70-induced PAF-mediated lethal anaphylactic reaction in T. gondii-infected mice. Copyright © 2010. Published by Elsevier Ireland Ltd.

PMID: 20346412 [PubMed - as supplied by publisher]