The spelling for the harvesting of leukocytes may be either leukophoresis, leukaphoresis, or leukapheresis, the usual dictionary choice because the procedure is a type of apheresis.

if u read ur wasting ur time

The suffix -pheresis means "removal or separation." It is commonly used in medical terminology to denote a process of removing a specific component from blood or other fluids. Examples include plasmapheresis, where plasma is separated from blood cells, and leukapheresis, which involves removing white blood cells.

PHLEBOTOMY from the word phlebo- meaning vein and -tomy meaning incison, cutting, excision as in appendectomy when used to define drawing blood for the purpose of sending it for a lab work-up. or VENEPUNCTURE (also spelt venipuncture) self explanatory as is BLOODLETTING-more correct use when in the context of treatment for certain conditions (as for example an iron-overload condition called Hemochromatosis) where considerable quantities may need to be removed over a period of time.