Immunomodulatory effects of hyperthermia on resisting WSSV infection in Procambarus clarkii.

Abstract

White spot disease remains a constant threat to aquaculture worldwide. Hyperthermia has been shown to reduce mortality in white spot syndrome virus (WSSV)-infected shrimps, but the mechanism still remains unclear. In this study, we sought to identify host immune factors that contribute to inhibition of WSSV infection during hyperthermia. In WSSV-infected red swamp crayfish Procambarus clarkii (Girard) cultured at 24 ± 1 °C, transcriptional levels of the heat shock protein 70 (Hsp70) gene showed a modest, 2.2-fold increase in haemocytes following 48 h post-infection (hpi). In contrast, in WSSV-infected crayfish cultured at 32 ± 1 °C, Hsp70 gene expression showed a rapid, 19.5-fold induction by 4 hpi. This suggests that Hsp70 plays a positive regulatory role in resistance to WSSV infection during hyperthermia. Furthermore, total haemocyte counts (THC) and phenoloxidase (PO) activity were both significantly increased in WSSV-infected crayfish cultured at 32 ± 1 °C by 48 hpi. Both may be critical for crayfish survival in the late stages of WSSV infection. Collectively, the up-regulation of host protein Hsp70 expression and increase in THC and PO activity suggest that hyperthermia has immunomodulatory effect that enhanced the resistance of P. clarkii to WSSV infection.

• Authors: X Wu, H Xiong, Y Wang, H Du
• Journal: Journal of fish diseases (J Fish Dis) Vol. 38 Issue 6 Pg. 567-74 (Jun 2015) ISSN: 1365-2761 [Electronic] England
• PMID: 24934502 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2014 John Wiley & Sons Ltd.

Chemical References

• HSP70 Heat-Shock Proteins
• Monophenol Monooxygenase

Topics

• Animals
• Astacoidea (immunology, virology)
• Gene Expression Regulation
• HSP70 Heat-Shock Proteins (genetics)
• Hemocytes (cytology, enzymology, immunology)
• Hot Temperature
• Monophenol Monooxygenase (metabolism)
• White spot syndrome virus 1 (physiology)