Rs. Anthony et al., FLOW-CYTOMETRY USING ANNEXIN-V CAN DETECT EARLY APOPTOSIS IN PERIPHERAL-BLOOD STEM-CELL HARVESTS FROM PATIENTS WITH LEUKEMIA AND LYMPHOMA, Bone marrow transplantation, 21(5), 1998, pp. 441-446
Quantifying progenitor cells in peripheral blood stem cell (PBSC) harv
ests by Row cytometric enumeration of CD34(+) cells does not account f
or cell viability. Cell membrane asymmetry in early apoptosis exposes
phosphatidylserine on the cell surface, This can be detected by staini
ng with annexin V FITC, Apoptosis in 30 autologous PBSC harvests mobil
ised by cyclophosphamide + G-CSF or standard chemotherapy + G-CSF was
analysed immediately after collection by dual-colour flow cytometry wi
th CD34 PE and annexin V FITC. Harvests contained a median of 3.4 x 10
(6)/kg (range 0.3-91.8) CD34(+) cells, Of these 87.6% (range 30-96.5)
were annexin V-. In 10% of harvests more than 50% of CD34(+) cells wer
e apoptotic, Differences in PBSC mobilisation or collection could not
explain the variation in annexin V binding, Cyclophosphamide + G-CSF s
ignificantly increased the yield of CD34(+) cells but did not increase
apoptosis. Comparison of consecutive harvests showed no difference in
the numbers of CD34(+) cells collected but found a significant decrea
se in apoptotic CD34(+) cells through multiple collections, Analysis o
f annexin V binding in PBSC harvests is a simple flow cytometry techni
que which gives additional information on the status of CD34(+) progen
itor cells.