Ex vivo purging of allogeneic marrow with L-Leucyl-L-leucine methyl ester. A phase I study.
Ex vivo purging of allogeneic marrow with L-Leucyl-L-leucine methyl ester. A phase I study.
复制标题
用 L-亮氨酰-L-亮氨酸甲酯离体清除同种异体骨髓。
作者：
C. Rosenfeld;D. Thiele;R. Shadduck;Z. Zeigler;J. Schindler
L-亮氨酰-L-亮氨酸甲酯（LLME）是一种亲溶酶体化合物，可通过二肽基肽酶I转化为细胞毒性T细胞、NK细胞和LAK细胞的膜溶解代谢物。用LLME离体处理鼠骨髓可改善急性移植物抗宿主病（GVHD），这导致考虑进行临床研究。由于LLME也抑制人祖细胞，因此启动了I期研究设计，以评价同种异体骨髓的离体净化对植入的影响。所有患者均接受环磷酰胺加全身照射的准备方案。GVHD预防包括环孢菌素+/-皮质类固醇。该研究包括19名患有高危疾病的患者，这些患者接受来自HLA相同的同胞（n = 12）或部分HLA匹配的家族供体（n = 7）的同种异体移植。在剂量递增研究中，用浓度为0.25 mM、0.375 mM和0.5 mM的LLME离体处理骨髓单核细胞。在浓度>或= 0.375 mM LLME时，骨髓NK和LAK活性基本消除。CD 8+细胞也减少。在0.5 mM LLME下，粒细胞巨噬细胞集落形成单位回收率为3%。中性粒细胞绝对计数达到500/μ L的中位时间为移植后17天（95%置信区间= 14-18天）。1例接受0.5 mM LLME治疗的骨髓患者死于继发性移植物衰竭。在每个可评价病例中记录了完全供体嵌合体。在LLME浓度>或= 0.375 mM LLME时，NK恢复延迟。18例可评价患者中有4例发生II/IV级GVHD。用LLME离体处理人骨髓减少NK活性、LAK活性、CD 8+细胞和粒细胞巨噬细胞集落形成单位，但不能完全预防急性GVHD。
L-Leucyl-L-leucine methyl ester (LLME) is a lysosomatropic compound that is converted by dipeptidyl peptidase I to metabolites that are membranolytic for cytotoxic T cells, NK cells, and LAK cells. Ex vivo treatment of murine marrow with LLME ameliorates acute graft-versus-host-disease (GVHD), which led to consideration of a clinical study. A phase I study design was initiated to evaluate the effects of ex vivo purging of allogeneic marrow on engraftment, since LLME also suppresses human progenitor cells. All patients received a preparative regimen of cyclophosphamide plus total body irradiation. GVHD prophylaxis consisted of cyclosporine +/- corticosteroids. This study included 19 patients with high risk disease undergoing allogeneic transplantation from an HLA-identical sibling (n = 12) or a partially HLA-matched family donor (n = 7). Marrow mononuclear cells were treated ex vivo in a dosage escalation study with LLME concentrations of 0.25 mM, 0.375 mM, and 0.5 mM. Marrow NK and LAK activities were essentially eliminated at concentrations > or = 0.375 mM LLME. CD8+ cells were also reduced. Granulocyte macrophage colony-forming unit recovery was 3% at 0.5 mM LLME. The median time to an absolute neutrophil count of 500/microliters was 17 days after transplantation (95% confidence interval = 14-18 days). One patient that received marrow treated with 0.5 mM LLME died of secondary graft failure. Complete donor chimerism was documented in each evaluable case. NK recovery was delayed at LLME concentrations > or = 0.375 mM LLME. Grade II/IV GVHD occurred in 4/18 evaluable patients. Ex vivo treatment of human marrow with LLME diminishes NK activity, LAK activity, CD8+ cells, and granulocyte macrophage colony-forming units, but does not totally prevent acute GVHD.