Hello whynot,
physcally like filtration or gravity effect , or chemical reaction antibodies reacts with ( against formely ) foreign agent in blood then after this reaction we could separate from blood.
Keep in mind that any surgical intervention is potentially lethal. So , something like transfusion is potentially lethal ... but it's very very very ....very very :) rare.
To pursue on "white cells in breast milk"
For the Watchtower a blood patch - formelly a total transfusion - is acceptable ...
albumin is acceptable because it cross placentae from one vascular system to another ... but red blood cells with nucleus do the same ... but red cell are forbiden :(
Another thing is twin it exist in the TT syndrome there is a problem in the vascular system at the placentae exchange surface where veins from a twin make a bond with veins or arter of the other twin ... if the bond is vein-vein bond it could be problematic ... if it 's vein-arter it's a BIG problem ... generally a surgical intervention is necessary to save babies.
But there is a third possibility ... an arter-arter bond ... and this one is not a problem at all ...
Yes I wrote arter-arter bond is not a problem , God permit that during 9 month of pregnancy that each twin could be totally transfused with the blood of is brother/sister ...
But when, they are born ... strange ... transfusion become forbiden
Some older reférence
Infection And Immunity Dec 1982 p 1073-1077
Infection And Immunity nov 1981 p 498-502 .
Infection And Immunity apr 1983 p 8-15
clin. exp. Immunol. (1979) 38, 585-597
JAMA Vol. 299 No. 19, May 21, 2008 . . . .
Ultrasound Obstetric Gynecology 2001 ; 17 ; 4-6
In fact, Watchtower and GB knows that there is not link between blood in Bible and Blood in medical care
in 1958 , if i corretly remember , the magazine Watchtower said ( then formelly the GB ... and God )
" each time the blood is mentioned in the scripture , it's for an food interdiction"
Best Regards