Viperin restricts chikungunya virus replication and pathology

102

121

There is a need to develop a single and highly effective vaccine against the emerging chikungunya virus (CHIKV), which causes a severe disease in humans. Here, we have generated and characterized the immunogenicity profile and the efficacy of a novel CHIKV vaccine candidate based on the highly attenuated poxvirus vector modified vaccinia virus Ankara (MVA) expressing the CHIKV C, E3, E2, 6K, and E1 structural genes (termed MVA-CHIKV). MVA-CHIKV was stable in cell culture, expressed the CHIKV structural proteins, and triggered the cytoplasmic accumulation of Golgi apparatus-derived membranes in infected human cells. Furthermore, MVA-CHIKV elicited robust innate immune responses in human macrophages and monocyte-derived dendritic cells, with production of beta interferon (IFN-␤), proinflammatory cytokines, and chemokines. After immunization of C57BL/6 mice with a homologous protocol (MVA-CHIKV/MVA-CHIKV), strong, broad, polyfunctional, and durable CHIKVspecific CD8؉ T cell responses were elicited. The CHIKV-specific CD8 ؉ T cells were preferentially directed against E1 and E2 proteins and, to a lesser extent, against C protein. CHIKV-specific CD8؉ memory T cells of a mainly effector memory phenotype were also induced. The humoral arm of the immune system was significantly induced, as MVA-CHIKV elicited high titers of neutralizing antibodies against CHIKV. Remarkably, a single dose of MVA-CHIKV protected all mice after a high-dose challenge with CHIKV. In summary, MVA-CHIKV is an effective vaccine against chikungunya virus infection that induced strong, broad, highly polyfunctional, and long-lasting CHIKV-specific CD8 ؉ T cell responses, together with neutralizing antibodies against CHIKV. These results support the consideration of MVA-CHIKV as a potential vaccine candidate against CHIKV. IMPORTANCEWe have developed a novel vaccine candidate against chikungunya virus (CHIKV) based on the highly attenuated poxvirus vector modified vaccinia virus Ankara (MVA) expressing the CHIKV C, E3, E2, 6K, and E1 structural genes (termed MVA-CHIKV). Our findings revealed that MVA-CHIKV is a highly effective vaccine against chikungunya virus, with a single dose of the vaccine protecting all mice after a high-dose challenge with CHIKV. Furthermore, MVA-CHIKV is highly immunogenic, inducing strong innate responses: high, broad, polyfunctional, and long-lasting CHIKV-specific CD8 ؉ T cell responses, together with neutralizing antibodies against CHIKV. This work provides a potential vaccine candidate against CHIKV.

Section: Discussionmentioning

confidence: 99%

Section: Hikungunya Virus (Chikv) Is An Alphavirus Of the Familymentioning

confidence: 99%

A Novel Poxvirus-Based Vaccine, MVA-CHIKV, Is Highly Immunogenic and Protects Mice against Chikungunya Infection

García-Arriaza

Cepeda

Holzmann

et al. 2014

102

121

“…Disease score was expressed as the relative increase compared to preinfection (0 dpi) and was calculated as follows: [(x Ϫ y)/y], where x represents the footpad measurement at the respective days postinfection and y is the measurement at 0 dpi. Ten microliters of blood from the tail vein was collected daily from 1 to 8 dpi and subsequently on every alternate day until 14 dpi to track for viremia (26,30,31).…”

Section: Methodsmentioning

confidence: 99%

“…Fixed tissues were then decalcified and embedded in paraffin wax before 8-m-thick sections were cut. Hematoxylin and eosin (H&E) staining was performed using established protocols as previously described (31,33). HistoQuest software (TissueGnostics) was used for the quantification of cellular infiltration.…”

Section: Methodsmentioning

confidence: 99%

The Antiviral Alkaloid Berberine Reduces Chikungunya Virus-Induced Mitogen-Activated Protein Kinase Signaling

Varghese

Thaa

Amrun

et al. 2016

Self Cite

113

100

Chikungunya virus (CHIKV) has infected millions of people in the tropical and subtropical regions since its reemergence in the last decade. We recently identified the nontoxic plant alkaloid berberine as an antiviral substance against CHIKV in a highthroughput screen. Here, we show that berberine is effective in multiple cell types against a variety of CHIKV strains, also at a high multiplicity of infection, consolidating the potential of berberine as an antiviral drug. We excluded any effect of this compound on virus entry or on the activity of the viral replicase. A human phosphokinase array revealed that CHIKV infection specifically activated the major mitogen-activated protein kinase (MAPK) signaling pathways extracellular signal-related kinase (ERK), p38 and c-Jun NH 2 -terminal kinase (JNK). Upon treatment with berberine, this virus-induced MAPK activation was markedly reduced. Subsequent analyses with specific inhibitors of these kinases indicated that the ERK and JNK signaling cascades are important for the generation of progeny virions. In contrast to specific MAPK inhibitors, berberine lowered virus-induced activation of all major MAPK pathways and resulted in a stronger reduction in viral titers. Further, we assessed the in vivo efficacy of berberine in a mouse model and measured a significant reduction of CHIKV-induced inflammatory disease. In summary, we demonstrate the efficacy of berberine as a drug against CHIKV and highlight the importance of the MAPK signaling pathways in the alphavirus infectious cycle. IMPORTANCEChikungunya virus (CHIKV) is a mosquito-borne virus that causes severe and persistent muscle and joint pain and has recently spread to the Americas. No licensed drug exists to counter this virus. In this study, we report that the alkaloid berberine is antiviral against different CHIKV strains and in multiple human cell lines. We demonstrate that berberine collectively reduced the virus-induced activation of cellular mitogen-activated protein kinase signaling. The relevance of these signaling cascades in the viral life cycle was emphasized by specific inhibitors of these kinase pathways, which decreased the production of progeny virions. Berberine significantly reduced CHIKV-induced inflammatory disease in a mouse model, demonstrating efficacy of the drug in vivo. Overall, this work makes a strong case for pursuing berberine as a potential anti-CHIKV therapeutic compound and for exploring the MAPK signaling pathways as antiviral targets against alphavirus infections. C hikungunya virus (CHIKV) is the causative agent of chikungunya fever, a disease spread by Aedes mosquitoes and characterized by a sudden onset of febrile illness, nausea, headache, and most importantly, severe and persistent musculoskeletal pain (1). It reemerged in tropical Asia and Africa 1 decade ago and since 2013 has infected more than 1.5 million people in the Americas (2). So far, no licensed vaccine or antiviral treatment exists to counter this disease. Over the years, many research groups have focused on...

“…In particular the type I interferon (IFN) pathway is critical for controlling viral replication and pathogenesis during the early stages of CHIKV infection, though this response does not completely ablate CHIKV replication or disease (61)(62)(63)(64)(65)(66). With respect to adaptive immunity, B cells and antibodies are known to be important, as CHIKV RNA persists in the serum of B cell-deficient mice for greater than a year and passive transfer of CHIKV-immune serum to IFNAR Ϫ/Ϫ mice protects against lethal infection (67).…”

mentioning

confidence: 99%

γδ T Cells Play a Protective Role in Chikungunya Virus-Induced Disease

Long

Ferris

Whitmore

et al. 2016

Chikungunya virus (CHIKV) is an alphavirus responsible for causing epidemic outbreaks of polyarthralgia in humans. Because CHIKV is initially introduced via the skin, where ␥␦ T cells are prevalent, we evaluated the response of these cells to CHIKV infection. CHIKV infection led to a significant increase in ␥␦ T cells in the infected foot and draining lymph node that was associated with the production of proinflammatory cytokines and chemokines in C57BL/6J mice. ␥␦ T cell ؊/؊ mice demonstrated exacerbated CHIKV disease characterized by less weight gain and greater foot swelling than occurred in wild-type mice, as well as a transient increase in monocytes and altered cytokine/chemokine expression in the foot. Histologically, ␥␦ T cell ؊/؊ mice had increased inflammation-mediated oxidative damage in the ipsilateral foot and ankle joint compared to wild-type mice which was independent of differences in CHIKV replication. These results suggest that ␥␦ T cells play a protective role in limiting the CHIKV-induced inflammatory response and subsequent tissue and joint damage.