Vaccines

World First Trial Of ‘Sweet’ Flu Vaccine

Antibodies For Avian Influenza

World First Trial Of ‘Sweet’ Flu Vaccine
First Published: Investigator - July 2008
Updated:

A trial of a plant extract enhanced influenza vaccine – one of the largest single-centre trials of its type in the world – is being conducted at Flinders Medical Centre.

Researchers are seeking up to 1,000 participants to trial the standard flu vaccine ‘boosted’ with a natural plant sugar.

The team has already demonstrated that the enhanced vaccine is effective in improving immunity against influenza in healthy people, and now hopes to show it improves immunity in the aged and chronically ill who are most at risk of complications when they get the flu.

‘Although the vaccine is still in its trial stage, we are hoping that this will prove to be the best defence against an influenza epidemic,’ chief investigator Dr Dimitar Sajkov said.

Vaccines are made up of two components: an antigen, which is a modified form of the influenza virus that enables the body to recognise and respond to the real thing; and an adjuvant, which acts as a ‘booster’ and amplifies the immune system’s response to the virus to make the vaccine more effective.

Scientists around the world have been searching for a suitable adjuvant to boost the effectiveness of the flu vaccine for decades without success.

A Flinders team led by Director of Diabetes and Endocrinology, Professor Nikolai Petrovsky has discovered that a natural sugar based adjuvant safely boosts the effectiveness of current commercial flu vaccines.

‘In a safety trial of 220 volunteers last year we were able to demonstrate that the adjuvantboosted flu vaccine was not only safe, but also very effective in terms of producing more immunity against the flu virus,’ Professor Petrovsky said.

He said adding the sugar-based adjuvant made the flu vaccine many times more effective. ‘Basically, you get to use less vaccine but get more immunity when you add the adjuvant.’

‘So in the event of a pandemic we could potentially stretch precious vaccine supplies up to 10-fold, enabling us to protect 10 times more people than with the traditional vaccine.’

Four groups are being targeted for the trial: people with chronic lung disease, heart disease, kidney disease, diabetes or healthy people aged over 60 years. Participants should not have already received a flu vaccination this year.

Those selected for the trial will receive either the standard flu vaccine or the adjuvant enhanced flu vaccine and then be followed up for a 12-month period. Researchers will determine from regular blood tests which vaccine provides participants with better protection against the flu.

Antibodies For Avian Influenza
First Published: Investigator - April 2006
Updated:

Professor David Gordon, Dr Tania Sadlon and Dr Peter Hallsworth from Microbiology and Infectious Diseases are working on developing a new diagnostic test for Avian Influenza (Bird Flu).

The aim of this project is to develop a blood test to discover whether human antibodies can be formed when there is exposure to avian influenza.

The body’s immune system uses antibodies to identify and neutralise the effects of bacteria and viruses. They are very specific to a particular virus and can only develop when a person has been exposed to that disease. Importantly, they are required to develop immunity.

However, because the avian flu is not related to normal strains of influenza, humans have no pre-existing immunity to these viruses.

Using gene technology, the research team will clone the H5 surface protein of the avian flu virus, which by itself is harmless.

The H5 gene will then be introduced into a yeast cell which will continue to produce this small component of the virus for the researchers to use in developing the blood test. By extracting the H5 protein and adding a sample of blood they will be able to see if antibodies are formed and bind to it.

This will give an indication of the body’s natural ability to develop antibodies against the avian flu virus. From this testing it will be possible to determine how the disease may spread, how many people will develop immunity and, the potential number of people who may become infected.

Another potential benefit from this test is the ability to measure antibodies and see if a vaccine will be effective. This would involve administering the vaccine, then running the developed blood test to see if antibodies exist.

“If an outbreak were to occur then an understanding of the pattern of infection, the potential mortality rate and the level of infection is vitally important in preparing strategies to deal with this,” says Professor Gordon.