Feature: Biosecurity batman

By Fiona Wylie
Wednesday, 27 July, 2011

Besides combating the deadly Hendra virus, Dr Lin-Fa Wang’s team is also looking at the host immune response in bats. “This is a very exciting area, but also a bit difficult as we don’t really know where to start, so we are attacking it in two ways.”

Their hypothesis-driven approach involves studying the known pathways and molecules of innate immunity, which is the first line of defence against viral infection in other mammals.

“We want to know if all the usual suspects, like interferons, cytokines and toll-like receptors, are present in bats, and which ones play an important role in coping with the viruses.

“Also, do these molecules function similarly or differently in bats compared to other know mammalian systems like humans? Perhaps there is a difference in one arm of the innate immunity response that protects bats from being infected with these viruses.”

A second discovery-driven approach will ensure that Wang and his team keep an open mind as he explains.

“Bats may possess some sort of unique immune molecules or pathways. If we just copy what we know from mice or humans we may never be able to f ind such a unique system in bats. This is going to be of course more difficult.”

Using several bat cell lines recently established by the group and some virus samples from the AAHL collection, Wang’s team is using the latest next-generation deep sequencing technology to identify genes that are commonly up- or down-regulated after viral infection, and particularly those altered in the early stages.

The aim is to discover what is different about the bat cells in terms of a global gene response to viral challenge, such as genes that are either unique or part of a novel network not shared by other mammals, or genes that are present in other mammals but for which a function has not been annotated.

Wang’s funding for this work initially came from the Australian Biosecurity CRC (2003-2010), and subsequently from other national and international sources, including a 5-year grant from the US National Institutes of Health to develop a Hendra vaccine.

“One of the tricks with this topic is, of course, convincing the more traditional Australian funding agencies like the NHMRC and ARC that studying bat immunology might reveal novel mechanisms for fighting infection more generally, and not just for these spill over viral diseases. Maybe we can learn from the bats!”

If nothing else, working on such a new and interesting area keeps Wang busy with up to 10 overseas trips and many local commitments a year. “Everyone seems to love our story and bats definitely have a certain fascination and mystery associated with them in almost every human culture.”