MECHANISMS OF SYNERGISTIC REGULATION OF STEM/PROGENITORS

描述：（改编自申请人的摘要）血细胞的控制 产生涉及细胞因子-细胞相互作用， 对造血干细胞有积极和消极的影响， 祖细胞 增长因素，如钢铁因素（SLF）和 集落刺激因子（CSF）可以共同作用， 方面的影响. 协同刺激可以被趋化因子抑制， 巨噬细胞炎性蛋白（MIP）-1 α，干扰素诱导型 蛋白质（IP）-10，IL-8和血小板因子（PF）4;趋化因子可 一起协同抑制生长。 我们假设 细胞内存在不同的重叠通路， 多种细胞因子协同刺激细胞增殖， 趋化因子的抑制作用发生在细胞内生长位点 因素协同刺激事件。 我们的目标是评估这些 使用因子依赖性骨髓细胞系的通路，并进行验证 在可行的情况下使用原电池。 具体目标是：（1）继续 研究Raf-1/MEK-1/MAP-激酶途径作为一种 介导的细胞增殖的协同刺激 SLF加CSF，以及c-AMP依赖性蛋白激酶A抑制剂 对Raf-1活化的活性作为 MIP-1 α和IP-10对MEKK 1/Sek 1/SAP-激酶和MKK 3/Hog/MAP-APK 2-激酶的作用。 激酶作为协同诱导细胞刺激可能位点 增殖及其由趋化因子的负调节。 确定 协同诱导的上调即刻表达的作用 反应基因如c-fos、junB、c-myc和c-fos是可能的位点 趋化因子的负调节。 尽可能评估上述内容 协同诱导抑制细胞增殖的位点 通过组合低浓度的以下任何两种物质 趋化因子：MIP-1 α、IP-10、IL-8或PF 4。2)建立一个角色 细胞周期蛋白依赖性激酶抑制剂p21 CIP-1和p27 KIP-1在 协同诱导细胞增殖刺激和确定 如果这是趋化因子抑制细胞生长的部位。 3)评价 真核细胞起始因子4 E（eIF 4 E）在细胞凋亡中的作用 在细胞中观察到的蛋白质合成水平的增强协同作用 SLF和CSF刺激增殖，并抑制 MIP-1 α、IP-10、IL-8和PF 4可诱导细胞凋亡。 4)评估 蛋白酪氨酸磷酸酶Syp和PRP-1C在协同诱导 趋化因子家族对细胞增殖刺激和抑制作用 成员

DESCRIPTION: (Adapted from Applicant's Abstract) Control of blood cell production involves cytokine-cell interactions in which cytokines manifest positive and negative effects on hematopoietic stem and progenitor cells. Growth factors such as steel factor (SLF) and a colony-stimulating factor (CSF) can act together to elicit synergistic effects. Synergistic stimulation can be suppressed by chemokines such as macrophage inflammatory protein (MIP)- 1alpha, interferon inducible protein (IP)-10, IL-8 and platelet factor (PF)4; chemokines can act together to synergistically suppress growth. It is our hypothesis that distinct and overlapping pathways exist within a cell to mediate synergistic stimulation of cell proliferation by multiple cytokines and suppression by chemokines is occurring at intracellular sites of growth factor synergistically stimulated events. Our goal is to evaluate these pathways using factor-dependent myeloid cell lines, with verification where feasible with primary cells. The specific aims are: 1) continue investigation of the role of the Raf-1/MEK-1/MAP-kinase pathway as a mediator of the synergistic stimulation of cell proliferation induced by SLF plus a CSF, and of the c-AMP-dependent protein kinase A inhibitory activity on Raf-1 activation as a site of the negative effects of MIP-1alpha and IP-10 on MEKK1/Sekl/SAP-kinase, and MKK3/Hog/MAP-APK2- kinase, as possible sites for synergistically-induced stimulation of cell proliferation, and its negative regulation by chemokines. Determine a role for the synergistically-induced up-regulation of immediate response genes such as c-fos, junB, c-egr and c-myc as possible sites of negative regulation by chemokines. Evaluate the above as possible sites for synergistically-induced suppression of cell proliferation by combinations of low concentrations of any two of the following chemokines: MIP-1alpha, IP-10, IL-8 or PF4. 2) Establish a role for the cyclin-dependent kinase inhibitors, p21CIP-1 and p27KIP-1 in synergistically-induced stimulation of cell proliferation and determine if this is a site of chemokine suppression of cell growth. 3) Evaluate a role for eukaryotic initiation factor 4E (eIF4E) in the greatly enhanced level of protein synthesis seen in cells synergistically stimulated to proliferate by SLF and a CSF and in the suppression of this by MIP-1alpha, IP-10, IL-8 and PF4. 4) Evaluate roles for the protein tyrosine phosphatases Syp and PRP-1C in synergistically-induced stimulation of cell proliferation and its suppression by chemokine family members.