Piera C, Vázquez A, Hernández M A, Plancha M C, Ruiz A, Mateos J J, Martín F, Ortega M L, Fuertes S, Pons F
Servei de Medicina Nuclear, Centre de Diagnòstic per la Imatge, IDIBAPS, Hospital Clínic, Barcelona, Spain.
Rev Esp Med Nucl. 2002 Sep-Oct;21(5):343-8. doi: 10.1016/s0212-6982(02)72105-8.
To modify the method of labelling leukocytes with 99mTc HM-PAO by centrifuging 15 minutes at low gravity (g) instead of sedimentation at a variable time (30-90 minutes) to obtain leukocytic rich plasma (LRP).
The g number recovering the greatest number of leukocytes was determined. The cellular composition of LRP obtained by centrifugation and sedimentation was analyzed. Lastly, labelling results in two groups of patients (p) were compared: one group of 118 p using the traditional sedimentation method (SM) and another of 124 p using the proposed centrifugation alternative (CM).
Centrifugation at 5xg produced the greatest recovery of leukocytes (93.1 5.1%). No significant difference was observed in leukocyte recovery in LRP obtained either by centrifugation or by sedimentation. However, red blood cell contamination was greater in centrifugation (12.8 4.9 x 108) than in sedimentation (7.7 3.5 x 108) (p < 0.0001). The comparison of the SM and the CM gave the following results:The number of leukocytes recovered in both methods was similar (73.9 15.1% vs 76.5 12.7%) with approximately the same platelet contamination (8.0 6.2 vs 8.4 6.5%). The number of red blood cell contaminants per leukocyte was 3.0 1.0 for the MS and 5.1 2.6 for the MC (p < 0.001). Labelling yield (LY) was somewhat higher for the CM (57.8 11.9%) than for the SM (50.8 12.6%) as a result of greater red blood cell contamination and superior radiochemical purity of the 99mTc HM-PAO used in the labelling by CM (90,9 5,9%) with regard to the SM (87.9 9.5%). No difference was observed in the scintigraphic images obtained with either of the methods, given the scarce uptake of the radiopharmaceutical by the red blood cells (3-7%) in comparison with the leukocyte uptake (70-90%).
The proposed MC considerably reduces the labelling time of leukocytes with 99mTc HM-PAO without affecting the quality of scintigraphic images and represents an important labelling alternative of great interest to the Radiopharmacy Units of Nuclear Medicine Services.
通过在低重力（g）下离心15分钟而非在可变时间（30 - 90分钟）沉降来改良用99mTc HM - PAO标记白细胞的方法，以获得富含白细胞的血浆（LRP）。
确定回收白细胞数量最多的g值。分析通过离心和沉降获得的LRP的细胞组成。最后，比较两组患者（p）的标记结果：一组118例患者使用传统沉降法（SM），另一组124例患者使用提议的离心替代法（CM）。
以5xg离心产生的白细胞回收率最高（93.1±5.1%）。通过离心或沉降获得的LRP中白细胞回收率未观察到显著差异。然而，离心时红细胞污染（12.8±4.9×10⁸）高于沉降时（7.7±3.5×10⁸）（p < 0.0001）。SM和CM的比较结果如下：两种方法回收的白细胞数量相似（73.9±15.1%对76.5±12.7%），血小板污染大致相同（8.0±6.2对8.4±6.5）。每白细胞的红细胞污染物数量，MS为3.0±1.0，MC为5.1±2.6（p < 0.001）。由于红细胞污染更大以及CM标记中使用的99mTc HM - PAO的放射化学纯度更高（90.9±5.9%），高于SM（87.9±9.5%），CM的标记产率（LY）略高于SM（57.8±11.9%对50.8±12.6%）。鉴于与白细胞摄取（70 - 90%）相比，红细胞对放射性药物的摄取很少（3 - 7%），两种方法获得的闪烁图像未观察到差异。
提议的CM方法显著缩短了用99mTc HM - PAO标记白细胞的时间，且不影响闪烁图像质量，是核医学服务放射性药物部门非常感兴趣的一种重要标记替代方法。
