Mouse antibodies with a human look may emerge as the next generation
of warriors in the fight against lung cancer and a type of leukaemia. Clinical
trials of the anti-bodies are now under way in the US.
女生小视频s genetically engineered the mouse antibodies so that their
surface amino acids resemble human ones. This should stop the patient鈥檚
immune system from perceiving them as 鈥榝oreign鈥� and so attacking them. The
antibodies could also be used to carry strong toxins such as ricin as 鈥榓mmunition鈥�
in attacking tumour cells, while leaving healthy cells unharmed.
鈥業nside, it鈥檚 a mouse antibody, but on its surface it looks human,鈥�
says Tony Rees, the executive technical director of Oxford Molecular, a
computer-aided molecular design company based in Oxford. Rees and his team
worked out how to disguise the antibodies through a technique they call
鈥榬别蝉耻谤蹿补肠颈苍驳鈥�.
Advertisement
The company started with two kinds of mouse antibody, both of which
bind strongly to human tumour cells. The company hopes that this characteristic
can be exploited by giving the antibodies strong toxins as 鈥榖aggage鈥� for
delivery to tumour cells.
Such deliveries would be impossible, however, if the mouse antibodies
were 鈥榝ound out鈥� and attacked by a patient鈥檚 immune system. Rees and his
team used software to work out the differences between the amino acids
on the surfaces of the two mouse antibodies, and those of typical human
antibodies. These differences give each species鈥� cells a characteristic
appearance at the molecular level. Using this data, they determined which
surface features had to be changed to 鈥榝ool鈥� the human immune system.
These changes were then genetically engineered by ImmunoGen, a biotechnology
company in Cambridge, Massachusetts. Engineers at ImmunoGen made a synthetic
version of the genetic instructions required to produce mouse antibodies
with the human arrangement of amino acids. They put this into live monkey
kidney cells, which produced the resurfaced antibodies in fermenters. In
laboratory tests, the resurfaced antibodies were able to bind to cancer
cells just as tightly as the original mouse antibodies.
