ENT researchers are targeting cytokine-producing cells they believe could be among the chief causes of chronic rhinosinusitis.

Dijana Miljkovic, who works in a team led by one of the world's foremost sinus surgeons Peter-John Wormald at The Queen Elizabeth Hospital in South Australia, recently discovered the presence of TH17 cells in chronic sinusitis sufferers.

Following the world-first discovery, Miljkovic is now determining exactly what those TH17 cells are producing.

"We found that patients with a very severe form of sinus disease have the TH17 cell more present in their polyps compared to patients with very mild forms of the disease or patients who don't have the disease at all," she said.

"If the TH17 cells produce molecules called cytokines, which either fight bacteria or cause inflammation, we'll be able to see what role this actual cell is playing.

"If it proves to be a more pathogenic role where it is continuing to cause the inflammation that we see in these patients then we'll be able to target it for therapies."

The research was funded by The Hospital Research Foundation and the Basil Hetzel Institute for Translational Health Research.

Miljkovic, who is also a PhD student at the University of Adelaide, said TH17 cells were mostly found in places where the host interacted with the environment such as mucous linings and in the skin.

"In the normal kind of setting TH17 cells will fight off different types of microbes but in a state of disease like chronic sinusitis where there's a dis-regulated immune response, the cell could be producing other things that are basically just continuing the inflammation even when the microbes have been cleared," she said.

Chronic sinusitis is an infectious disease characterized by severe inflammation of the sinus cavities. Symptoms include severe headaches, facial pain and nasal congestion. It can also impact sleep, taste, sense of smell and significantly reduce a patient's quality of life. More than 13 million people in the United States alone are estimated to be living with chronic sinusitis.

Miljkovic said patients typically presented claiming they felt like they had "a flu that never goes away".

"Basically the treatment is antibiotics and steroid treatment. The medical therapies don't work for a lot of people so they have to go through multiple operations because the polyps just keep growing back," she said.

"Although the TH17 could be clearing the bacteria, rather than disappearing once it has carried out its function, it may just hang around, continue to cause the inflammation when it's not really needed and lead to the growth of these polyps that can lead to nasal blockage and severe headaches. By the end of the year we're hoping to confirm whether the cells are pathogenic or non-pathogenic and then we can move to the next step."

Miljkovic said there were clinical trials in patients with psoriasis and rheumatoid arthritis, which targeted TH17 cytokines.

"So we can look into something quite similar."