Sphingosine-1-Phosphate Receptors in Human B Cells: Expression, Role and Signaling

通过对人B细胞中1-磷酸鞘氨醇（S1 P）功能的研究，我们希望有助于对人B细胞恶性肿瘤的认识，并为诊断、分期和治疗提供新的工具和方法。使用原代人B细胞、来自B细胞恶性肿瘤的样品、人B细胞系和人源化小鼠模型，我们研究了S1 P受体如何引发和调节对S1 P的细胞应答，干扰调节人B细胞发育、生长和分化的信号。通过比较正常和恶性B细胞，我们希望我们可以描述S1 P依赖途径如何促进淋巴瘤的发生。通过慢病毒基因转移将S1 P受体和荧光蛋白如GFP之间的融合蛋白引入人B细胞系中，以分析S1 P受体对S1 P结合的响应、受体内化和活细胞中的区室化。这些结果将揭示B细胞中S1 P受体之间的功能差异，确定受体内的关键残基和结构域，并提供对S1 P诱导的信号与必需B淋巴细胞特异性受体之间相互作用的了解。由于新的治疗方法是基于S1 P类似物的应用，预计的结果应有助于了解这些治疗的有益和不利影响。

Studying the functions of sphingosine-1 phosphate (S1P) in human B cells we hope to contribute to the understanding of human B cell malignancies and to provide new tools and procedures for diagnosis, staging and treatment. Using primary human B cells, samples from B cell malignancies, human B cell lines, and humanized mouse models, we examine how S1P receptors elicit and modulate cellular responses to S1P, interfere with signals that regulate human B cell development, growth and differentiation. By comparing normal and malignant B cells we hope that we can characterize how S1P-dependent pathways contribute to lymphomagenesis. Fusion proteins between S1P receptors and fluorescence proteins like GFP are introduced into human B cell lines by lentiviral gene transfer to analyze the S1P receptor response to S1P binding, receptor internalization and compartmentalization in living cells. The results should reveal the functional differences between S1P receptors in B cells, define the critical residues and domains within the receptors and provide insight into the interactions between signals induced by S1P and essential B-lymphocyte specific receptors. Since new therapeutic approaches are based on the application of S1P analoga the projected outcome should help in understanding the beneficial and adverse effects of these therapies.