Complex sentence: Transfusion of granulocytes would have been a solution to the problem; however, granulocytes live only ~ 10 hours in the circulation (for days in spleen or other tissue), which gives a very short-lasting effect.
Split into simpler sentences: Transfusion of granulocytes would have been a solution to the problem. However, granulocytes live only ~ 10 hours in the circulation (for days in spleen or other tissue), which gives a very short-lasting effect.