A vaccine against mesothelioma, a cancerassociated with exposure to asbestos, has shown early promise in its first clinical trial.

The experimental vaccine is an example ofdendritic cell (DC)-based immunotherapy, in which the body’s own immune system is harnessed to target and destroy cancer cells.

In the vaccine, a sample of the patient’s ‘dendritic’ immune cells are mixed with proteins taken from their tumour.

When implanted back into the patient, these cells can then activate other elements of the patient’s immune system, known as T-cells, and encourage them to attack and destroy the tumour.

Researchers at Erasmus Medical Center in The Netherlands have previously shown that DC vaccinesbring about an anti-tumour response in mice and decided to test the technique in humans.

They enrolled ten people who had recently been diagnosed with a form of mesothelioma called ‘malignant pleural’ mesothelioma, and who had been previously treated with chemotherapy.

The team took a sample of dendritic cells from each patient’s blood, and exposed them to proteins from their tumours.

The dendritic cell samples were also exposed to a ‘marker’ protein called keyhole limpet hemocyanin (KLH).

Patients then received three injections of their ‘activated’ dendritic cells over a two-week period.

Publishing their findings in the American Journal of Respiratory and Critical Care Medicine, the researchers revealed that all ten patients had antibodies to the KLH marker in their blood, confirming that the vaccines had brought about an immune response.

Further tests on four of the patients’ tumours revealed that three of the tumours had got smaller, although this could not be conclusively or directly linked to the vaccine…. (more…)