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Scientists have engineered an antibody that blocks the allergic reaction against common pollen when applied inside the nose of mice.

Around one in five people are allergic to pollen, known as , and their symptoms cause the loss of millions of school and workdays every year.

Scientists say the prevalence of hay fever has been surging for decades and is likely to continue to rise – a change so fast that genetic and health changes can’t be solely responsible.

Improved hygiene, widespread use of antibiotics and antiseptics, lifestyle changes, diet, pollution, and climate change are also believed to contribute to the increase.

But a new study, published in the journal Frontiers in Immunology, offers fresh hope for sufferers.

Researchers in Kazakhstan have engineered an antibody from mice, which when applied to the inside of the nose stops the rodents from developing hay fever and asthma symptoms in response to mugwort pollen.

Mugwort is the most common cause of pollen allergies in central Asia and parts of Europe, where between 10% and 15% of people with are allergic to it.

Study senior author Kaissar Tabynov said: “This is the first time a monoclonal antibody designed to block a specific pollen allergen has been delivered directly into the nose, and been shown to protect against in the upper and lower airways.

“In the future, similar antibodies could be developed for other major pollen allergens, such as ragweed or grass.

"This opens the door to a new generation of precision treatments that are fast-acting, needle-free, and tailored to individual allergen sensitivities.”

He said the traditional treatment is allergen-specific immunotherapy, where patients are exposed to gradually increasing doses of the allergen until they become desensitised.

But that treatment doesn’t work for all patients, and in recent decades, so-called "allergen-specific monoclonal antibody therapy" has increasingly come to the fore as an alternative.

Tabynov explained that in allergen-specific monoclonal antibody therapy, researchers engineer antibodies of the IgG class, which either specifically recognise the allergen itself and block it, or bind to IgE antibodies in general.

In either case, it prevents the allergen from triggering an allergic reaction.

But a disadvantage is that usually the antibodies need to be injected into the bloodstream – until now.

Tabynov, of the (KazNARU), said: “Our method acts immediately and locally at the lining of the nose, by neutralising the allergen on contact.

"This ‘molecular shield’ not only prevents IgE antibodies from being activated, but may also reduce inflammation through other mechanisms, such as calming immune cell responses and promoting regulatory pathways."

The research team injected mice with a dose of mugwort pollen, stimulating them to produce antibodies against it.

The mice were then humanely euthanised and their spleens harvested to isolate white blood cells.

The use of mice was approved by the local , under the .

The white blood cells were then fused with lab-grown cancer cells from mice with multiple myeloma.

That yielded five immortal "hybridoma" cell lines, each of which secreted a single type of antibody against mugwort pollen.

A series of tests showed that the most powerful was produced by the hybridoma cell line XA19, which was selected for further development.

To test their efficiency, purified antibodies from XA19 were administered to the interior of the nose of five mice, which had been stimulated to become allergic to mugwort pollen through injections of pollen extract.

Five other mice, which had been similarly sensitised but received a placebo, served as a positive control, while a further five mice were the negative control - neither sensitised to the pollen nor given monoclonal antibodies.

Three weeks later, all the mice were exposed three times under anaesthesia to an aerosol of mugwort pollen, as well as to pollen extract delivered directly inside the nose.

The results showed that the sensitised mice given the XA19 antibody displayed a "major reduction" in compared to the controls.

They showed a weaker ear swelling response to the pollen, a common allergic reaction in rodents.

They also rubbed their nose less frequently, indicating less irritation of the upper airways.

Their full lung capacity was preserved upon exposure to the pollen, and they also showed less inflammation inside their nostrils.

The researchers concluded that the monoclonal antibody from XA19 is "effective" in blocking allergic reactions against mugwort pollen triggered by IgE, at least in mice.

Tabynov added: “Before this treatment can be tested in people, we need to adapt the antibody to make it suitable for humans – a process called ‘humanisation’ – and conduct additional preclinical safety and efficacy studies.

“If these are successful and provided we have adequate support, we could begin clinical trials in two to three years, though bringing it to market would likely take five to seven years.

"We are already planning for this transition and working on scaling up production.”