I've heard from first and second hand accounts that Jehovah Witnesses abstain from blood (i.e. transfusions)  because they view it as a sin to accept blood.

I've always taken the blood to be an important symbol for those who profess to believe in Christ since it is via the spilling of blood that atones for Man's sin furthermore according to the bible the greatest price was paid when Jesus shed his blood by dieing on the cross to redeem mankind.

How then can people who believe in Christ have such a policy concerning blood?

I understand that Jesus is regarded differently from Man but I wonder if Jehovah Witnesses believe in the redemption of the blood of Jesus?