The information at the bottom of this post is from the Keep Yourself in God's Love book, the appendix, and is a bit of the discussion of fractions......what I find interesting is this book uses a lot of the information from the November 2006 Our Kingdom Ministry article on blood fractions, but omits the statement:
"Of course many fractions are derived from blood that has been donated for medical purposes."
This seems to be more than just an oversite. I asked my wife where fractions come from and she referred to Keep Yourself in Gods Love book, so she said she really did not know (which I think was acting dumb for the sake of not having to answer the question), but if this omitted statement were in the Keep Yourself book, there would be no doubt.
By leaving this statement out, it would be more palatable for a JW to be willing to accept a fraction since it is not written before them in WTS literature that the fractions are from blood that was not "poured out on the ground"......
Blood Fractions
and Surgical Procedures
Blood fractions. Fractions are derived from the four primary blood
components-red cells, white cells, platelets, and plasma. For example, red cells
contain the protein hemoglobin. Products developed from human or animal
hemoglobin have been used to treat patients who have acute anemia or massive
blood loss.
Plasma-which is 90 percent water-carries scores of hormones, inorganic salts,
enzymes, and nutrients, including minerals and sugar. Plasma also carries clotting
factors, antibodies to fight disease, and such proteins as albumin. If someone is
exposed to a certain disease, doctors might prescribe injections of gamma globulin
extracted from the plasma of people who already had immunity. White blood cells
may be a source of interferons and interleukins, used to treat some viral infections
and cancers.
Should Christians accept therapies incorporating blood fractions? The Bible does not
give specific details, so each one must make his own conscientious decision before
God. Some would refuse all fractions, reasoning that God's Law to Israel required
that blood removed from a creature be "[poured] out upon the ground."
(Deuteronomy 12:22-24) Others, while refusing transfusions of whole blood or its
major components, might accept treatments involving a fraction. They may reason
that at some point fractions that have been extracted from blood cease to represent
the life of the creature from which the blood was taken.