Washington: In pioneering work, researchers from the University of Colorado-Boulder have grown "humanised" models of mice in the lab that will lead to better testing of cancer therapies.
In the new model called "XactMice", human blood stem cells are used to grow a "humanised" mouse immune system prior to human tumour transplantation to test promising anti-cancer therapies.
With a human-like immune system interacting with a human-like tumour in this model, researchers can test anti-cancer therapies in an environment much more akin to that found in real patients.
The new model may be especially important in testing immunology-based therapies which attempt to recruit the immune system to target tumour tissues.
"One of the reasons that anti-cancer immune therapies have been difficult to develop is that perhaps we have not had adequate models. Now we have a model that will enable some of those studies," said Antonio Jimeno, director of the University of Colorado's school of medicine.
The team performed a bone marrow transplant on these "humanised" mice.
Mice were treated with radiation to knock down the existing blood system and then human stem cells from human cord blood were introduced to regrow the blood system with elements of the human immune system.
"After a few months, the mice became chimeras (a single organism composed of genetically distinct cells) - with human blood cells and hence a human immune system," added Yosef Refaeli, co-author from the Gates Centre for Regenerative Medicine.
Human tumours grown in mouse models have long been used to test promising anti-cancer therapies.
In further research, small tumour samples will be taken from melanoma and also head and neck cancer patients.
Blood stem cells from these patients will be used to "humanise" mice and then patients' tumours will be grown on mice matched with their immune systems.
The mice will then be treated with anti-cancer therapies and the results will be compared with results in the human patients.
"This might be a better model for several areas of cancer (and non-cancer) research, and since each mouse provides a lot of information, we will be able to do more with less mice," Jimeno added.
In addition to a humanised immune system, the new model allows patient-derived tumours to develop in a much more human-like environment.
"For example, this will be a valuable platform to understand the basis of response to immune therapies and find better ways to give the right drug to the right patient at the right time," the authors concluded in a paper that was published in the journal Oncogene.
