Experimental infection of king crab hemocytes with a herpes-like virus in culture

Abstract

To date, herpes-like viruses have been repeatedly found in wild king crab populations. In this study, freshly collected hemocytes of the red king crab Paralithodes camtschaticus have been experimentally exposed in culture to the herpes-like virus from thawed antennal gland samples from infected blue king crabs P. platypus. After 3–4 months of cultivation, significant differences in the pigmentation were observed between control and virus-infected hemocytes. Using Raman spectroscopy, we detected two obligatory peaks, characteristic for melanin identification, in the spectra of pigmented inclusions in harvested virus-infected hemocytes. These peaks are absent in the spectra obtained from control hemocytes. The cells of virus-infected cultures were viable after 10 months, while all control uninfected hemocytes were lost. As demonstrated by electron microscopic studies, virus-like particles become abundant at 7 days post-inoculation. Our results suggest that hemocytes could be used as a suitable model system for studies of crab pathogens. The in vitro studies confirm previous findings regarding the presence of viral infection in the natural population of king crabs.