PetSavers funds project to improve the diagnosis of feline infectious peritonitis

9 January 2024

Professor Danièlle Gunn-Moore received BSAVA PetSavers’ funding for a master’s degree by research project entitled Acute phase protein and microRNA signatures for the diagnosis and prognosis of feline infectious peritonitis.

Student Rachael Hammond (shown right) tells us more. Ever since I can remember I have always been fascinated by science, although it took me a few years to realize that what I was mainly interested in was microorganisms and how they affect us both clinically and agriculturally. To this day I am still amazed that these minuscule organisms which are all around us can have such devastating effects on health, as well as plant and livestock production. As my first degree in microbiology and biotechnology progressed, I found that I wanted to focus on host-pathogen interactions, meaning I could combine my two favourite areas of study: pathogens and immunology. I love how the body is (usually) able to fight off infectious disease and, in response, how in some cases these same pathogens can evade these systems.

As well as being a scientist I am also a cat lover, and this is what led me to undertake my master’s research project at The Royal (Dick) School of Veterinary Studies. I joined the vet school as a technician, and now as a researcher I try to make a difference in veterinary medicine, even if only in a small way. Playing a part in keeping families and their pets together, even for just a short while, is the most rewarding part of my job. Unfortunately, over the years, I have seen many cats that haven’t been able to recover from their illnesses; feline infectious peritonitis (FIP) being just one of them. FIP had been invariably fatal until recently, but now it is no longer a death sentence due to the advent of novel antivirals GS-441524 and Remdesivir. Access to these drugs has been a literal lifesaver for cats across the country, including Louis who suffered from a non-effusive form of FIP which progressed to neurological involvement. The photos show him before starting treatment with oral GS-441542 and at 12 weeks post-diagnosis (Figure 1). His symptoms have now almost resolved completely. It is so important to diagnose cats with FIP quickly and accurately, which is why I asked two people who are more than qualified in this subject if they would like to work together. Professor Danièlle Gunn-Moore and Dr Alex Malbon have both contributed extensively to understanding FIP and I couldn’t have chosen a better team if I tried.

FIGURE 1: (Left) Louis on the feline ward before starting treatment with oral GS-441542; (Right) Louis at home 12 weeks post-diagnosis on GS medication.

What the research will tell us
We hope that through our research we will be able to determine if acute phase proteins (APPs) α1-acid glycoprotein [AGP], serum amyloid A [SAA] and haptoglobin [Hp] and micro (mi)RNA signatures can be used in the diagnosis, response to treatment and even prognosis of FIP. We are investigating whether these particular inflammatory proteins, which are commonly elevated in cats with FIP, can be used as biomarkers when treating cats with antivirals. FIP treatment typically lasts for 84 days, so we want to see if baseline concentrations of these APPs decrease whilst undergoing treatment, as they may help to tell how well a cat is responding alongside clinical signs and routine investigations. We also hope to see if miRNA analysis can be used in the diagnosis and prognostication of FIP as little is currently known about the feline miRNAome; this approach proved helpful in Covid patients.

Early findings
We are still in the early stages of our research as I am undertaking the MScR part-time to allow me to continue with my regular job. We are currently recruiting patients for our study and are following them from diagnosis until the end of their treatment and for a further 12 weeks after this. It is within the first 6 months of stopping treatment with GS or Remdesivir that we think cats are more likely to relapse, if they are going to, hence why we have chosen to continue to follow up with patients even though their treatment has ended. From the small amount of data we have collected so far, we have seen AGP concentrations decline within a few weeks of treatment; by the end of the treatment period these have fallen below the reference range of 500 µg/ml. Interestingly, feedback from colleagues treating FIP in Japan, where they have a cage-side test for SAA, shows that SAA falls within days of starting successful treatment. So, measuring SAA may be useful in determining whether treatment is working, while AGP may be more useful to know when treatment can be stopped. But these are just thoughts from a few cases. We have yet to assess SAA and Hp responses to antivirals ourselves because we need to recruit more patients as we are batch-testing these, and our miRNA analysis should begin shortly.

As veterinarians and researchers alike are still learning how cats respond to FIP antivirals, we need to collect more data. Ultimately, we will be able to understand better this distressing disease and should be able to develop appropriate treatment protocols tailored to each cat. This will, of course, take time due to the long duration of treatment required in these cases (12 weeks in the first instance, but longer if they relapse or respond poorly to treatment), plus the observation period which follows (another 12 weeks). But it will be worth it if it helps save cats’ lives. Given the fact that very little is known about feline miRNAs, we aim to generate pilot data that will be the backbone of potential future studies which we hope may even lead to novel and sensitive diagnostic tests for FIP.

Facing challenges
The biggest challenge so far has been sample recruitment. Although it is thought that 5–12% of cats develop FIP, especially if they are young pedigree cats in multi-cat households, it can be difficult to diagnose as clinical signs can often be nonspecific. Reaching a diagnosis of FIP can take time as there is no single test that can confidently confirm the disease. This, coupled with expensive investigations and costly treatment, means that we are not always able to save every cat with FIP. This only emphasizes the need for more rapid diagnostics and further research. We are confident that now we can advertise our studies we will be able to generate more than enough data.

Personally, this experience has further confirmed that I would like to pursue research full-time. It has given me access to new equipment and assays that I have never used before, allowing me to learn new techniques and develop new and existing lab skills. I am also able to tap into years of experience through my supervisors whom I will be forever grateful for taking a chance on me.

I highly recommend applying to the PetSavers MDR grant. As a non-vet student, I doubted I would be successful as I was sure that there would be far more qualified people out there with better ideas than myself. Without the help from PetSavers, I would never have been able to embark on this new journey into the huge world of research. My success in this award just proves this opportunity is open to anyone with an interest in science and veterinary medicine. So, if you have that voice in the back of your head saying you won’t be good enough, ignore it and just go for it!

About the author
I graduated from Napier University in 2016 where I studied microbiology and biotechnology. Since leaving university I’ve held positions in commercial microbiology laboratories, and I have also worked in the Histopathology Department within NHS Lothian. For the last 4 years, I have worked as a laboratory technician in the Clinical Pathology lab based at The Royal (Dick) School of Veterinary Studies.