1. The Impact of Circulation Access in Allogeneic Peripheral Blood Stem Cell Harvest Shang-Hsien Yang1, Tso-Fu Wang2,3, Shu-Hui Wen4, Sung-Chao Chu3, Ruey-Ho Kao3,4, Shu-Huey Chen1,2,4 Department of Pediatrics 1, Buddhist Tzu-Chi Stem Cell Center 2,HematoOncology 3, Hualien Tzu-Chi Hospital, Tzu-Chi University 4 Background The pre-aphaeresis circulating CD34+ cell count in peripheral blood had been proven to be the strongest predictor for the outcome of peripheral blood stem cell (PBSC) harvest but there’re still great variations among different studies. Procedural settings were seldom discussed but might be an important factor affecting harvest outcome after mobilization. In this study, we analyzed the procedural effects on the relationship of peripheral blood circulating CD34+ cell and the aphaeresis yield.. Materials and methods From September 2006 to December 2008, 337 donors had PBSC donation in our institute after G-CSF mobilization. We evaluated the the relationship between donor factors, procedural settings (vein or artery) and harvest CD34+ cell products. The comparisons of procedural settings and aphaeresis products for arterial and venous group were performed and the relationships among study variables were assessed using Pearson’s correlation. Results The correlation between circulating CD34+ cells and stem cell harvest yields in 422 aphaeresis was analysed to clarify the impact of aphaeresis settings. The harvest outcomes were also compared in different access groups. A highly significant correlation (r=0.8310, p<0.0001) was noted. The correlation coefficient was significant higher in arterial group than that in venous group (r=0.9218 vs. 0.7952, p<0.0001) but not difference between was found high and low flow rate groups (r=0.8376 vs. 0.8193, p=0.5515). Although the harvest yields were not different (23.1 vs. 26.0 x 106/L, p=0.67), the circulating CD34+ cells were relative lower in the arterial group (71.3 vs. 62.1/µL, p=0.07). The harvest yields were not different in those poor mobilisers. Conclusions Arterial access could be an alternative option for its higher correlation efficient between circulating CD34+ cell and final harvest yield. * Data presented as number (%). BMI indicates body mass index; G-CSF, granulocyte colony stimulating factor; BW, body weight; WBC, white blood cell; PLT, platelet. Fig 1. Correlation analysis between pre-apheresis circulating CD34+ cell count and apheresis CD34+ cell yields. The correlation coefficient and p value are shown. (A) All donors (r = 0.8310, p 44.66ml/min (r = 0.8376, p < 0.0001). (E) Donors had flow rate < 44.66ml/min (r = 0.8193, p < 0.0001). Table I. Donor characteristics, procedural settings and harvest products. Table II. Procedural settings and harvest results in arterial and venous groups on Day 1. Day 1 (n=337)Day 2 (n=85) meanmedianrangemeanmedianrange Gender (male, %)*205 (60.8%)44 (51.8%) Access (artery, %)*113 (33.5%)27 (31.8%) Age (year)32.131.020-5433.331.020-54 Body height (cm)167.0167.5145.5-190.7167.1167.0150.0-188.0 BMI (kg/m 2 )23.823.317.0-42.422.622.11017.4-34.7 Body weight (kg)66.766.042.0-109.063.52563.042.0-105.4 G-CSF dose (  g) 645.4600.0450-1050610.6600.0450-1050 G-CSF (  g/kg) 9.68 8.33-10.999.619.458.39-10.91 Processing volume (L)17.118.08.1-18.76.46.04.0-12.0 Aphaeresis volume per donor BW (ml/kg)266.0264.9113.0-428.7103.796.052.7-183.9 Recipient BW (kg)62.062.87.0-108.066.965.028.0-108.0 Running time (mins)385.3390.0191-490148.5143.0115-230 Flow rate (ml/min)44.4644.9130.96-59.2142.9543.0921.11-73.67 Collected volume (ml)209.3215.062.0-276.062.363.029.0-123.0 Pre-aphaeresis WBC (x10 3 /  l) 47.2546.3519.56-80.5934.8232.0817.68-67.46 Pre-aphaeresis platelet (x10 3 /  l) 20620177-42712011855-292 Pre-aphaeresis CD34 + cells (/  l) 76.768.710.0-214.831.422.16.8-108.0 Total CD34 + count (x10 6 cells)457.4414.019.0-1395.154.645.212.0-206.3 CD34 + cell dose (x10 6 cells/Kg)7.987.110.25-34.60.830.610.17-3.72 CD34 + cell yield (x10 6 cells/L)26.824.41.1-77.58.67.51.8-34.4 Artery (n=113)Vein (n=224)P value Processed volume (L)18 (11.0-18.7)18 (8.1-18.6)0.1549 Flow rate (ml/min)45.7 (31.0-59.2)44.7 (31.3-56.5)0.0134 Time (min)382 (230-475)394 (191-490)< 0.0001 Collect volume (ml)214 (107-276)215 (62-265)0.8702 Total CD34 + count (x10 6 cells)385.1 (75.8-1264.4)442.2 (19.0-1395.1)0.5259 Recipient BW (kg)60 (10.6-108)65 (7-105)0.0607 CD34 + cell Dose < 2x10 6 /kg*4 (3.5%)19 (8.5%)0.1416 CD34 + cell Dose < 4x10 6 /kg*18 (15.9%)59 (26.3%)0.0443 CD34 + cell Dose < 5x10 6 /kg*29 (25.7%)76 (33.9%)0.1550 2nd aphaeresis*23 (20.4%)63 (28.1%)0.1578 Day 1 cell dose < 5x10 6 /kg but no 2nd aphaeresis* 6 (5.3%)13 (5.8%)0.9485 Pre-aphaeresis CD34 + cells (/  l) 62.1 (10.0-195.7)71.3 (13.6-214.8)0.0725 CD34 + cell dose (x10 6 cells/kg)6.73 (0.76-30.31)7.16 (0.25-34.58)0.7717 CD34 + cell yield (x10 6 cells/L)23.12 (4.8-69.9)26.0 (1.1-77.5)0.6660 A B C D E Data are presented as the median (range) and a p value is derived from Mann-Whitney test. * Data presented as number (%) and p value was calculated by the Chi-square test. BMI indicates body mass index; G-CSF, granulocyte colony stimulating factor; BW, body weight; WBC, white blood cell; PLT, platelet.