Tilapia lake virus downplays innate immune responses during early stage of infection in Nile tilapia (Oreochromis niloticus)

Mugimba, Kizito K.; Lamkhannat, Mustapha; Dubey, Saurabh; Mutoloki, Stephen; Munang’andu, Hetron Mweemba; Evensen, Øystein

doi:10.1038/s41598-020-73781-y

Cited by 30 publications

(47 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Various factors and mechanisms such as differences in innate immunity or host cell permissiveness are likely involved in weight-dependent susceptibility to TiLV infection. Prior to this study, a different expression of cytokines and immune-related genes was reported in tilapia during TiLV infection (Mugimba et al, 2020;Pierezan et al, 2020;Sood et al, 2021). For example, Mugimba et al (2020) showed that the TiLV viral load and expression of immune-related genes were inversely correlated in the brain and spleen of infected fish.…”

Section: Discussionmentioning

confidence: 88%

“…Prior to this study, a different expression of cytokines and immune-related genes was reported in tilapia during TiLV infection (Mugimba et al, 2020;Pierezan et al, 2020;Sood et al, 2021). For example, Mugimba et al (2020) showed that the TiLV viral load and expression of immune-related genes were inversely correlated in the brain and spleen of infected fish. Alternatively, a mechanism to facilitating viral persistence in younger fish e.g., production of immunosuppressive cytokines, could play a role in suppressing the host response to TiLV.…”

Section: Discussionmentioning

confidence: 88%

See 1 more Smart Citation

Weight-dependent susceptibility of tilapia to tilapia lake virus infection

Roy¹,

Yamkasem²,

Tattiyapong³

et al. 2021

PeerJ

View full text Add to dashboard Cite

The emergence of tilapia lake virus (TiLV) has had a severely negative impact on global tilapia aquaculture. TiLV infection has been reported at different life stages of tilapia, with more emphasis on fry and fingerlings; however, the virulence and pathology of TiLV at different tilapia size remains unexplored. In this study, tilapias from a single spawning were raised to 5 g, 25 g, and 65 g, and subsequently challenged by the intraperitoneal injection and cohabitation of a virulent strain of TiLV. The cumulative mortality, viral load, and histopathology of the fish were determined until 22 days post-infection (dpi). The cumulative mortality of the 5 g, 25 g, and 65 g fish was 85% (±1.67), 55% (±2.89), and 51.67% (±7.49), respectively. At 14 dpi, the mean TiLV load in the liver of the 5 g fish was significantly higher than in the 25 g and 65 g fish. All the weight groups showed severe pathological changes in the liver, spleen, and intestine after TiLV infection, but no particular difference was otherwise noted during the study with the exception of higher pathological scores in the liver of the small fish at 14 dpi. Overall, this study indicated that small fish are more susceptible to TiLV infection than large fish. Although multiple factors, including environmental factors, farm management practices, strains of virus could contribute to different susceptibility of fish to viral infection, the present study provides the evidence to support that fish weight affects the mortality and clinical outcome during TiLV infection. More intensive measures such as strict biosecurity and disease surveillance during the susceptible weight should therefore be emphasized to reduce the impact of this virus.

show abstract

Section: Discussionmentioning

confidence: 88%

Section: Discussionmentioning

confidence: 88%

Weight-dependent susceptibility of tilapia to tilapia lake virus infection

Roy¹,

Yamkasem²,

Tattiyapong³

et al. 2021

PeerJ

View full text Add to dashboard Cite

show abstract

“…TiLV has a linear, negative-sense single-strand RNA genome with 10 segments and about 10.323 kb in total length (22,23). Interestingly, a high level of TiLV was observed in the brain of infected tilapia (23,25), and this was correlated with the clear histopathological changes (23) and activation of the expression of genes involved in the antiviral immune response in the tilapia brain (25,26). We recently described the TiLV infection model in adult and larvae of zebrafish (27,28), and our virus tropism study revealed that in adult fish the highest viral load of TiLV was found in the brain (27).…”

Section: Introductionmentioning

confidence: 99%

Tilapia Lake Virus-Induced Neuroinflammation in Zebrafish: Microglia Activation and Sickness Behavior

et al. 2021

View full text Add to dashboard Cite

In mammals, the relationship between the immune system and behavior is widely studied. In fish, however, the knowledge concerning the brain immune response and behavioral changes during brain viral infection is very limited. To further investigate this subject, we used the model of tilapia lake virus (TiLV) infection of zebrafish (Danio rerio), which was previously developed in our laboratory. We demonstrated that TiLV persists in the brain of adult zebrafish for at least 90 days, even when the virus is not detectable in other peripheral organs. The virions were found in the whole brain. During TiLV infection, zebrafish displayed a clear sickness behavior: decreased locomotor activity, reduced food intake, and primarily localizes near the bottom zone of aquaria. Moreover, during swimming, individual fish exhibited also unusual spiral movement patterns. Gene expression study revealed that TiLV induces in the brain of adult fish strong antiviral and inflammatory response and upregulates expression of genes encoding microglia/macrophage markers. Finally, using zebrafish larvae, we showed that TiLV infection induces histopathological abnormalities in the brain and causes activation of the microglia which is manifested by changes in cell shape from a resting ramified state in mock-infected to a highly ameboid active state in TiLV-infected larvae. This is the first study presenting a comprehensive analysis of the brain immune response associated with microglia activation and subsequent sickness behavior during systemic viral infection in zebrafish.

show abstract

“…Furthermore, the presence of the TiLV genomic RNA in the infected brain has also been determined by in situ hybridization (Bacharach et al., 2016; Dong et al., 2017). However, these findings were limited at suggesting that the brain is one of the target tissues for transcription and replication of the virus (Mugimba et al., 2020). In fact, the fish brain divides into different regions and each part is responsible for certain functions (Table 1) (Roberts & Ellis, 2012; Sado et al., 2020).…”

Section: Introductionmentioning

confidence: 99%

Dissecting the localization of Tilapiatilapinevirus in the brain of the experimentally infected Nile tilapia, Oreochromisniloticus (L.)

Dinh-Hung

Sangpo

Kruangkum

et al. 2021

Journal of Fish Diseases

View full text Add to dashboard Cite

Tilapia tilapinevirus or tilapia lake virus (TiLV) is an emerging virus that inflicts significant mortality on farmed tilapia globally. Previous studies reported detection of the virus in multiple organs of the infected fish; however, little is known about the in‐depth localization of the virus in the central nervous system. Herein, we determined the distribution of TiLV in the entire brain of experimentally infected Nile tilapia. In situ hybridization (ISH) using TiLV‐specific probes revealed that the virus was broadly distributed throughout the brain. The strongest positive signals were dominantly detected in the forebrain (responsible for learning, appetitive behaviour and attention) and the hindbrain (involved in controlling locomotion and basal physiology). The permissive cell zones for viral infection were observed mostly to be along the blood vessels and the ventricles. This indicates that the virus may productively enter into the brain through the circulatory system and widen broad regions, possibly through the cerebrospinal fluid along the ventricles, and subsequently induce the brain dysfunction. Understanding the pattern of viral localization in the brain may help elucidate the neurological disorders of the diseased fish. This study revealed the distribution of TiLV in the whole infected brain, providing new insights into fish–virus interactions and neuropathogenesis.

show abstract

Tilapia lake virus downplays innate immune responses during early stage of infection in Nile tilapia (Oreochromis niloticus)

Cited by 30 publications

References 47 publications

Weight-dependent susceptibility of tilapia to tilapia lake virus infection

Weight-dependent susceptibility of tilapia to tilapia lake virus infection

Tilapia Lake Virus-Induced Neuroinflammation in Zebrafish: Microglia Activation and Sickness Behavior

Dissecting the localization of Tilapiatilapinevirus in the brain of the experimentally infected Nile tilapia, Oreochromisniloticus (L.)

Contact Info

Product

Resources

About