Autologous Bone Marrow Transplantation - Blog Science Connections

628 Peripheral Stem Cell Transplantation
Of particular interest is the rapid hematopoietic reconstitution after
ABSCT in patients who received more than 5x10" CFCJ-GM/kg b.w.: 1000
leukocytes, including 500 granulocytes, were reached within 2 weeks after
ABSCT. The rapid early rise in peripheral leukocyte counts may be explained
by assuming the transfusions contained large numbers of committed
progenitor cells, which, like CFCI-GM in the in vitro assay, take about 10-14
days to differentiate to mature cells. Transfusing these committed
progenitors, which differentiate early and subsequently appear as the first
cohort of circulating neutrophils, is clinically important. It significantly
reduces the times of isolation and hospitalization owing to treatmentinduced
neutropenia.
Long-term hematopoiesis, however, is reestablished by early pluripotent
stem cells; they take longer to give rise to differentiated progeny. Hence the
pattern of hematopoietic reconstitution of platelets appears to be composed
of successive cohorts of cells that differentiate from various progenitor and
stem cells.
Figure 4 illustrates the correlation between the numbers of mononuclear
cells and CFU-GMs transfused and early hematopoietic recovery in évaluable
patients from Table 2. Early hematopoietic recovery seems to correlate more
with the number of mononuclear cells transfused ( r = .65 for 1000 WBC and
r = .54 for 50,000 platelets) than with the number of CFCl-GMs transfused ( r =
Time to reach 1000 WBC per (il PB after ABSCT
Time to reach 50,000 Platelets per til PB after ABSCT
Time to reach 1000 WBC per |il PB after ABSCT
Time to reach 50000 Platelets per |il PB after ABSCT
Days
20 40 60 B0 100 120
Days
Figure 4. Correlation between number of cells transfused and hematopoietic recovery after
autologous blood stem cell transplantation (ABSCT).