Treating disease via an immune ‘on/off’ switch

30 May 2014, Immune system, Multiple Sclerosis

Understanding how the immune system induces, enhances, or supresses an immune response is a crucial component of immunology. Knowledge of this opens the doors to targeting components of the immune system, which in turn allows researchers to manipulate immune cells to respond in a way that is therapeutically beneficial.

To put it simply, researchers aim to find a way in which they can harness specific immune responses and turn them ‘on’ or ‘off’ like a light switch.

‘ON’ FOR CANCER

By flicking the switch ‘on’, appropriate immune cells are called to action so that they recognise and attack potential threats. This form of immune response is vital in diseases like cancer where some tumours are able to persist in the body due to their development of mechanisms that enable them to evade or counteract the immune response. The melanoma vaccine being trialled in our current Phase I clinical trial is an example of this form of immune therapy.

‘OFF’ FOR ASTHMA, ALLERGY, GOUT, INFLAMMATORY BOWEL DISEASE AND MS

In contrast, by flicking the switch ‘off’, unwanted immune responses such as those that occur in allergic diseases and multiple sclerosis are suppressed or blocked. Treatments that promote this suppressed reaction would effectively instruct the immune system to tolerate the harmless substances that elicit misdirected immune responses in certain individuals.  In other words, they calm the immune system down, reducing the inflammation that leads to the symptoms of these diseases.

THE KEY IMMUNE CELLS

Specialised immune cells called dendritic cells (pictured above) play a central role in guiding the development and direction of an immune response and could therefore be considered as key players in the immune ‘on/off’ switch.  Understanding how best to direct their activity is an area of ongoing investigation here at the Malaghan Institute.