Tumour immunology and immunotherapy

many genetic and environmental factors can cause tumors to form for instance UV radiation from the Sun can damage DNA and other structures in melanocytes which are the pigment producing cells in the skin chronic damage to melanocytes by UV radiation leads to most cases of melanoma which is a type of skin cancer as melanomas grow they can eventually spread to other sites in the body such as the lungs and liver the cells of the immune system are continuously monitoring our tissues natural killer cells or NK cells sent stress associated molecules on damaged and cancerous cells dendritic cells or dcs activate cytotoxic T cells which can then send tumor associated antigens using their T cell receptor and other Co receptors once activated NK cells and cytotoxic T cells release perforin and granzymes these molecules punch holes in the surface of the chima cells causing them to die by apoptosis helper T cells support these responses they help DC's to activate cytotoxic T cells and they produce cytokines such as interferon gamma that recruit and activate more NK cells as the tumor evolves genetic changes occur that can give some tumor cells a survival advantage this means tumors are often heterogeneous for instance tumor cells may no longer express the molecules that are sensed by the killer immune cells as the immune system continues to kill the tumor cells it can recognize the cells it can't sense more prevalent this is immuno editing it leads to the emergence of a tumor that can't be detected by the immune system some tumor cells actively suppress t-cells by expressing inhibitory molecules such as PDL one PDL one binds to the PD one receptor on t-cells and deactivates them this is an immune checkpoint in addition tumor cells can attract immune cells that suppress the activity of other immune cells thereby supporting tumor growth these immunosuppressive cells include regulatory t-cells and certain types of myeloid cells therefore the tumor microenvironment is like the scene of a battle between two opposing immune responses one side of the immune system is attacking the tumor while the other side is helping it to grow scientists are developing immunotherapies to help strengthen the immune attack one approaches adoptive t-cell transfer cytotoxic t-cells taken from patients with melanoma are selected for their ability to attack tumor cells the best killers are infused back into the patient treating patients with cytokines such as interleukin 2 and interferon alpha can also boost the activity of anti-tumor immune cells an alternative approach is to target the immune checkpoints for instance antibodies that bind to PD one stop this molecule from switching off cytotoxic T cells another immune checkpoint being targeted is ctla-4 blocking this molecule helps DC's to drive anti tumour t-cell responses not all patients will respond to these immunotherapies and some responses will be delayed combining immunotherapies with chemotherapy or radiotherapy can lead to a better response in some patients immunotherapies can themselves be combined for example PD one and ctla-4 blockade can improve responses when administered in combination activating the immune system has risks some patients develop harmful side effects when their immune system attacks healthy cells nevertheless there have been encouraging results from clinical trials this animation has focused on melanoma but it's becoming clear that immunotherapies can be used to treat many different types of cancer you

Channel: nature video

Views: 1,042,164

Rating: 4.9113503 out of 5

Keywords: Immunotherapy (Medical Treatment), Immunology (Field Of Study), Research (Industry)

Id: K09xzIQ8zsg

Length: 5min 3sec (303 seconds)

Published: Thu Sep 17 2015

Reddit Comments

[u/7ypo]

What kind of predictions has your research yielded?

[u/Veeno_]

What part of this immuno-cancer relationship are you currently studying? Man am I falling in love with immunology. Feels like there's so much clinical potential

[u/withlacoochee]

Thank you for spreading this knowledge. I've gotten severely downvoted on here more than once for telling people that the immune system can in fact prevent/combat cancer.

[u/dvaccaro]

Our research has developed the technology to label various immune system cells with iron nanoparticles such that the labeled cells can be followed in the body by MRI. These nanoparticle-labeled cells are also highly magnetic. Therefore it is now possible to focus immune system cells at any location in the body through the use of external magnetic fields. Thus we have the potential of putting the immune system inside of a tumor for immunotherapy.