Chinese vaccine promises to stop plaques building up in arteries

In trials on mice, an experimental nanovaccine created by Chinese scientists inhibited the development of a disease that can lead to blood clots, stroke and heart attacks

Chinese researchers said they have developed a mixture of nanovaccines to prevent the formation of plaque in arteries, the main cause of cardiovascular disease, which is the leading cause of death worldwide. The team of experts said that the experimental vaccine proved to be effective in trials on mice.

The vaccine addresses a disease known as atherosclerosis, which causes the formation of plaques – deposits of fatty substances, cholesterol and cellular debris in the arteries that can lead to blood clots, strokes and heart attacks.

The nanovaccine was developed by a team of researchers from institutions such as Nanjing University of Science and Technology and the University of Science and Technology of China.

To create the nanovaccine, the team attached an antigen that triggers an immune response against atherosclerosis and an immune response enhancer to tiny iron oxide nanoparticles. When the resulting nanovaccine was injected into mice fed a diet high in cholesterol, the team found that the triggered immune response was able to prevent the development of atherosclerosis.

‘Our results demonstrate the efficacy of the bidirectional delivery strategy of the nanovaccine in combating atherosclerosis,’ the team said in a paper published in March in the peer-reviewed journal Nature Communications.

Atherosclerosis is a progressive disease with many causes. Risk factors for this disease include high cholesterol, high blood pressure, smoking, obesity, type 1 diabetes and diets high in saturated fat.

According to the researchers, various immunotherapeutic methods have been studied in animal models of atherosclerosis. One promising molecule that triggers the body’s immune response to prevent the progression of atherosclerosis is the p210 antigen.

The team decided to attach the antigen to superparamagnetic iron oxide nanoparticles and separately attach an immune adjuvant, a substance used in combination with the antigen to enhance the immune response, to the different nanoparticles. They found that combining the resulting particles into a vaccine mixture was more effective in mice than attaching antigen and adjuvant to the same nanoparticles.

‘In studying vaccination against atherosclerosis, an ongoing challenge is deciphering the mechanism of action – a prerequisite for transferring the vaccination protocol to humans,’ the team said. They found that the vaccine works because the nanoparticles help immune cells accept antigen and adjuvant, which activate dendritic cells – that is, immune cells that enhance the response by presenting antigens on their surface to be shown to other cells.

This in turn stimulates T cells – white blood cells that play a key role in immune functions – and triggers the production of antibodies against p210. It turned out that the humoral response, carried out via antibodies, lasted longer than the T-cell response.

‘The duration of protection by nanovaccines against atherosclerosis requires further study,’ the research scientists tell us. And they add that the mice showed no signs of liver toxicity and the vaccine did not lead to ‘undesirable spread’ to organs such as the heart and lungs.