Exploring of Primate Models of Tick-Borne Flaviviruses Infection for Evaluation of Vaccines and Drugs Efficacy

PLoS One

Liubov I. Kozlovskaya¹  Andrey V. Timofeev¹  Natalia V. Tereshkina¹  Yulia V. Rogova¹  Lidiya Iu. Romanova¹  Natalia S. Pripuzova¹  Mikhail F. Vorovitch¹  Larissa V. Gmyl¹  Liubov L. Terekhina¹  Galina G. Karganova¹  Karina G. Grishina¹ 

[1] FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia

关键词: Monkeys;    Viremia;    Vaccines;    Central nervous system;    Spleen;    Lymph nodes;    Tick-borne encephalitis;    Viral vaccines;   

DOI  :  10.1371/journal.pone.0061094

学科分类：医学（综合）

来源: Public Library of Science

【 摘 要 】

Tick-borne encephalitis virus (TBEV) is one of the most prevalent and medically important tick-borne arboviruses in Eurasia. There are overlapping foci of two flaviviruses: TBEV and Omsk hemorrhagic fever virus (OHFV) in Russia. Inactivated vaccines exist only against TBE. There are no antiviral drugs for treatment of both diseases. Optimal animal models are necessary to study efficacy of novel vaccines and treatment preparations against TBE and relative flaviviruses. The models for TBE and OHF using subcutaneous inoculation were tested in Cercopithecus aethiops and Macaca fascicularis monkeys with or without prior immunization with inactivated TBE vaccine. No visible clinical signs or severe pathomorphological lesions were observed in any monkey infected with TBEV or OHFV. C. aethiops challenged with OHFV showed massive hemolytic syndrome and thrombocytopenia. Infectious virus or viral RNA was revealed in visceral organs and CNS of C. aethiops infected with both viruses; however, viremia was low. Inactivated TBE vaccines induced high antibody titers against both viruses and expressed booster after challenge. The protective efficacy against TBE was shown by the absence of virus in spleen, lymph nodes and CNS of immunized animals after challenge. Despite the absence of expressed hemolytic syndrome in immunized C. aethiops TBE vaccine did not prevent the reproduction of OHFV in CNS and visceral organs. Subcutaneous inoculation of M. fascicularis with two TBEV strains led to a febrile disease with well expressed viremia, fever, and virus reproduction in spleen, lymph nodes and CNS. The optimal terms for estimation of the viral titers in CNS were defined as 8–16 days post infection. We characterized two animal models similar to humans in their susceptibility to tick-borne flaviviruses and found the most optimal scheme for evaluation of efficacy of preventive and therapeutic preparations. We also identified M. fascicularis to be more susceptible to TBEV than C. aethiops.

【 授权许可】

CC BY