Antigen Engineering has allowed scientists to formulate a cancer vaccine that is effective in preventing liver cancer in mice.
By modifying Alpha-Fetoprotien (AFP), an antigen for liver cancer, Dr. Yukai He was able to make it so that the immune system would still recognise it, but would keep the protein expressed by cancer cells. AFP is expressed during development and by around 80% of common liver cancer cells, but is not common within healthy adults.
The cancer vaccine was tested using a model that exposed mice to chemical known to induce liver cancer and was successful around 90% of the time. Mice who received the modified AFP were not only significantly less likely to develop liver cancer, they also had more T cells which would be able to target re-emerging liver cancer. Recurrence of the disease is highly likely within the first five years, with a recurrence rate of 70%.
Dr Yukai He, immunologist at the Medical College of Georgia and Georgia Regents University Cancer Center, has been granted $1.6 million by the National Cancer Institute and intends to continue moving his studies toward human applications.
His new studies will involve taking healthy blood and removing monocytes – the plentiful white blood cells that can become dendritic cells – and developing them to be given the vaccine. These cells will then be returned to the mice to see if they will produce AFP-focused T cells. He is hoping that a safer delivery method and liogand packaged with the antigen in a ‘tripartite’ vaccine will prove to be successful.
Carcinogen- and hepatitis B-induced liver cancer models are being used for the studies as hepatitis vaccines have reduced liver cancer rates in many other countries. So far only two vaccines are approved as preventatives for cancer by the FDA: the hep B vaccine and vaccines against the human papillomavirus (HPV).