Defenseless (Image: Phanie Agency/Rex Features)
THE creation of a lab rat with no functioning immune system is opening up the possibility of more realistic testing of cancer treatments, transplantation techniques and other therapies. Such animals are useful to researchers because the immune response in a normal animal can complicate test results.
Until now, mice have been the only lab animals readily available with no immune system. They are produced by knocking out key genes in mouse embryonic stem cells required for the immune system to function. Development of a rat equivalent has lagged behind, as the first “knockout rats” were…
