DIRECT MEASUREMENT OF LEUKEMIC CELL TURNOVER (SYNTHESIS AND REMOVAL) IN PATIENTS

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。B细胞慢性淋巴细胞白血病(B-CLL)是一种临床异质性的疾病，因为一些患者在不需要治疗的情况下可以长时间存活，而另一些患者尽管接受了积极的治疗，但死亡很快。然而，在细胞水平上，这种疾病被认为是同质性的，原因是来自正常CD5+B淋巴细胞的白血病克隆积累。我们小组的数据表明，B-CLL病例在细胞水平上是不同的，根据白血病B细胞的分子和表型特征，B-CLL病例至少分为两个亚组。这一区别具有非常重要的临床意义，因为不同组的患者遵循明显不同的过程和结果。在这个方案中，我们将通过研究新诊断的、未经治疗的B-CLL患者来更准确地确定这些亚组中的白血病细胞有何不同。这些研究包括一系列体外实验(目标1和3)，旨在分析细胞激活和成熟的表面和细胞内标记的表达以及基因表达谱。此外，将进行一系列体内实验(目标2)，以确定不同亚组之间是否存在白血病细胞动力学(增殖与细胞死亡)的差异。这些研究涉及患者在12周内摄取氚水，并对新产生的白血病细胞中氚DNA的出现和消失进行纵向分析，以此作为细胞周转的衡量标准。同时，还将测定多形核白细胞和T淋巴细胞的动力学。多形核白细胞将作为正常自体非淋巴细胞群迅速转换的指示物，T细胞将作为克隆扩增的自体正常淋巴细胞群。我们将把这些白血病和非白血病细胞动力学的活体测量与其他目前使用的B-CLL生长和疾病进展的临床标记物相关联。该方法有助于了解不同患者B-CLL细胞体内生物学的差异，并可能比目前使用的参数更敏感和更快速地分析B-CLL的进展。这种动力学方法也可能识别新的预后亚群的患者。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. B cell chronic lymphocytic leukemia (B-CLL) cases are clinically heterogeneous since some patients survive for prolonged periods without requiring therapy, while others die rapidly despite aggressive treatment. However at the cellular level, the disease has been considered homogeneous, resulting from the accumulation of a leukemic clone derived from a normal CD5+ B lymphocyte. Data from our group has documented that B-CLL cases are heterogeneous at the cellular level and segregate into at least two subgroups based on the molecular and phenotypic features of the leukemic B cells. This distinction has very significant clinical implications since the patients in the different groups follow strikingly different courses and outcomes. In this protocol, we will determine more precisely how the leukemic cells in these subgroups differ by studying newly diagnosed, untreated B-CLL patients. These studies involve a series of in vitro experiments (Aims 1 & 3) designed to analyze the expression of surface and intracellular markers of cell activation and maturation as well as gene expression profiling. In addition, a series of in vivo experiments (Aim #2) will be carried out to determine if there is a difference in leukemic cell kinetics (proliferation vs. cell death) between the subgroups. These studies involve the ingestion of deuterated water by patients over a 12 week period, with longitudinal analyses of the appearance and disappearance of deuteriated DNA in newly created leukemic cells as a measure of cell turnover. Concomitantly, the kinetics of polymorphonuclear leukocytes and T lymphocytes will be determined. Polymorphonuclear leukocytes will serve as indicators of a rapidly turning over population of normal autologous non-lymphoid cells, and T cells will serve as an autologous normal lymphocyte population that is clonally expanded. We will correlate these in vivo measurments of leukemic and non-leukemic cell kinetics with other currently used clinical markers of B-CLL growth and disease progression. This approach should help to understand differences among patients of the in vivo biology of B-CLL cells, and may represent a more sensitive and rapid method to analyze B-CLL progression than the currently used parameters. This kinetic approach also may to identify new prognostic subgroups of patients.