The issue here, with all fusion protein, is many fold.

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These are part of the immune system and, if suitably treated with a substance called a fusion protein, can be used to make prostate-cancer cells vulnerable to immune attack.

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Using such fusion proteins, a scientist can follow exactly where a protein moves in a cell, or in an animal's body.

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But as Matthew Herper observed back in June, Medtronic has received something of a black eye this year in connection with its promotion of a key product, recombinant human bone morphogenetic protein-2, (rhBMP-2) which is designed to speed healthy bone growth and fusion in patients with back pain.

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