The investigation of a rampaging cricket STD that makes its victims both sterile and rabidly lustful led a Dalhousie University researcher to a somewhat less salacious discovery that could, with further exploration, have meaningful implications for human treatment options.
Biologist Dr. Shelley Adamo published a research paper titled, “A viral aphrodisiac” in the Journal of Experimental Biology last month.
She said her colony of crickets contracted the highly virulent IIV-6/CrIV virus from a reptile brought into the lab for a separate study.
She said she noticed her females had stopped laying eggs, though they seemed otherwise completely healthy – not lethargic and eating normally.
“When I opened up a female, I was shocked. This female was not a little sick, she was a lot sick,” said Adamo Thursday, adding the cricket had bloated, bluish fat cells where her eggs should have been.
After confirming the presence of the virus, Adamo said she determined that the virus was responsible for significantly increasing their sexual appetites – an effect not documented in any cricket pathogen.
However, what’s more notable than the aphrodisiac effect is that the virus severed communication between the immune and central nervous systems, blocking normal ‘sick’ behaviours such as lethargy or reduced appetite.
“My guess is, it does what viruses do, which is hijack the genome of its host,” she said. “It’s forcing the host to make viral proteins and suppressing the expression of immune-related proteins. And the actual molecular details of that would be cool to figure out, but we didn’t get that far.”
Adamo said sexually transmitted infections in most mammals are also asymptomatic, suggesting a similar “blocking” mechanism that’s beneficial to the continued survival of the disease.
She said figuring out how viruses suppress immune signals could lead to insights in regulating the intracellular signaling systems – which could have important implications for some human treatment therapies that involve stimulating the immune system.
“Unfortunately, they have serious side effects, and most of these side effects have to do with overactivating these communication signals, so people feel extremely ill,” she said. “So…there would be benefits if you could figure out how to regulate that without suppressing immune function, that would be the key.”