Studies of Chemokine-Receptor Interactions with Chemokines and alarmins

趋化因子受体与趋化因子和警报素相互作用的研究

• 批准号: 7965166
• 负责人: JOOST J OPPENHEIM
• 金额: $ 115.53万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7965166
• 关键词: Accounting; Adjuvant; Antibody Formation; Antigens; Antiviral Agents; Autoimmunity; B-Lymphocytes; C3H/HeN Mouse; CCR6 gene; Cell Line; Cells; Chimeric Proteins; Colon Carcinoma; Coupled; Cytoplasmic Granules; Cytotoxic T-Lymphocytes; Defensins; Dendritic Cells; Development; Endotoxins; Eosinophil-Derived Neurotoxin; Epithelial Cells; Family; G-Protein-Coupled Receptors; GTP-Binding Proteins; Gastrointestinal tract structure; Gi-alpha protein; Homologous Gene; Host Defense; Human; IgG1; Immune; Immune response; Immunity; Immunization; Immunologic Adjuvants; Infection; Inflammation; Ingestion; Injury; Interleukin-4; Interleukin-5; Laboratories; Lactoferrin; Leukocytes; Ligands; Malignant Neoplasms; Mononuclear; Mus; Myelogenous; Natural Killer Cells; Organism; Pain; Parasitic Diseases; Pattern; Pertussis Toxin; Preparation; Production; Property; Receptor Cell; Recruitment Activity; Signal Transduction; Source; System; T-Lymphocyte; TLR2 gene; TLR4 gene; Therapeutic; Tissues; Tracheobronchial; Trauma; Trees; Tumor Antigens; Vaccines; alpha-Defensins; aluminum sulfate; antimicrobial peptide; base; beta-Defensins; cathelicidin; cell injury; chemokine; chemokine receptor; cytokine; eosinophil; granulocyte; granulysin; in vivo; keratinocyte; macrophage; melanoma; member; microbial; monocyte; receptor; response; tumor; tumor growth

Overall, my laboratory investigates the interactions of cognate chemokine ligands and chemokine mimics with G-protein coupled chemotactic receptors and activating receptors with resultant effects on inflammation, immunity, autoimmunity, cancer and algesia. We have shown that a variety of antimicrobial peptides (AMPs) mimic chemokines and also have the capacity to rapidly activate host immune responses. We have proposed calling these early warning signals alarmins. Alarmins are characterized by having chemotactic activity for cells expressing GiPCR, together with the capacity to activate iDC to mature into antigen- presenting, T lymphocyte activating dendritic cells (mDC) with resultant in vivo immunoadjuvant effects. These activities of alarmins, if administered together with an antigen, result in considerable augmentation of both cellular and humoral in vivo immune responses to the antigen. We previously identified both alpha and beta types of defensins as alarmins with chemotactic and activating effects on immature dendritic cells (iDC) and in vivo immunoadjuvant effects. Some of the beta defensins interact with the CCR6 chemokine receptor, while alpha defensins interact with an as yet unknown G-Protein Coupled Receptors (GiPCR). Another antimicrobial peptide known as cathelicidin (LL37) and its murine homologue CRAMP are chemotactic for FPRL-1 receptors expressed on monocytes and precursors of iDC, induce the maturation of iDC and are equally as potent adjuvants in vivo as alum. Although alarmins are structurally distinct, they are rapidly released from granules of leukocytes or damaged cells. Alarmins can also be induced in response to proinflammatory stimulants by keratinocytes or epithelial cells lining the GI tract, GU tract and tracheobronchial tree. As such, alarmins probably represent an early warning system to alert the host defense to danger signals During the previous year we also investigated the immune activating and chemotactic effects of another leukocyte granule derived alarmin known as eosinophil derived neurotoxin (EDN), which is a member of the RNAse family, and has antiviral activity including anti-HIV activity. EDN based on its interactions with a pertussis toxin susceptible GiPCR is chemotactic for iDC, and mDC. In addition, EDN based on interactions with TLR2 activates iDC to produce multiple proinflammatory cytokines and to mature into mDC. EDN also has potent in vivo immunostimulating effects. However, EDN activated DC in a manner that preferentially promotes a Th2 pattern of polarization with greater induction of IgG1 antibody production by B-lymphocytes and the production of Interleukin (IL)-5 and 13, but not IL-4 or IFNgamma. Although EDN has the properties of an alarmin this suggests that the adjuvant effect of EDN may prove more useful in vaccines aimed at immunization against parasitic diseases rather than tumors. We have also shown that lactoferrin has alarmin activities. We have used GMP preparations of human lactoferrin (TLF) for our studies. TLF is being evaluated as an anti-tumor therapeutic at other centers. TLF is chemotactic for monocytic APCs, but uses an unidentified receptor to recruit and mobilize mononuclear cells. Since C3H/HeJ, unlike C3H/HeN, mice are not activated by TLF, this suggests TLR4 is involved in the immune adjuvant effects of TLF. TLF activity appears to survive transport through the gastrointestinal tract of mice. We are therefore investigating whether TLF can exacerbate IBD and whether ingestion of lactoferrin may thus predispose subjects to develop colon cancer. During the past year we identified granulysin, which is normally stored in the granules of natural killer (NK) cell and cytotoxic T cells (CTL), as an alarmin. Both 9kDa and 15kDa forms of granulysin are chemotactic for immature myeloid derived dendritic cells (iDC) and can activate such iDC to mature into antigen presenting dendritic cells (mDC). Granulysin interacts with an unidentified pertussis toxin sensitive Gi alpha protein cell receptor (GiPCR) to induce chemotactic responses. Like TLF, granulysin also fails to induce maturation of C3H/HeJ iDC, suggesting TLR4 is involved in the immune activating effect of granulysin. The possibility that endotoxin contamination accounts for the TLR4 stimulating effect of granulysin has been ruled out. Consequently, we can add NK and CTL cells to eosinophils, granulocytes, epithelial cells and macrophages as sources of alarmins. We are at present preparing fusion proteins consisting of some of the more potent alarmins fused to several different melanoma tumor antigens in order to obtain a potent antitumor vaccine.

总体而言，我的实验室研究了同源趋化因子配体和趋化因子模拟物与G蛋白偶联趋化受体和激活受体的相互作用，从而对炎症、免疫、自身免疫、癌症和疼痛产生影响。我们已经证明，各种抗菌肽(AMPs)模拟趋化因子，也具有快速激活宿主免疫反应的能力。我们提议将这些早期预警信号称为警报。Alarmins的特征是对表达GiPCR的细胞具有趋化活性，并能够激活IDC成熟为抗原提呈，T淋巴细胞激活树突状细胞(MDC)，从而产生体内免疫佐剂效应。如果与抗原一起使用，警报的这些活性会导致对该抗原的体内细胞和体液免疫反应的显著增强。我们先前发现α和β类型的防御素都是对未成熟树突状细胞(IDC)具有趋化和激活作用以及体内免疫佐剂作用的警戒素。一些β防御素与CCR6趋化因子受体相互作用，而阿尔法防御素与一种未知的G蛋白偶联受体(GiPCR)相互作用。另一种抗菌肽长春花素(LL37)及其小鼠同源基因对表达在单核细胞和IDC前体细胞上的FPRL-1受体具有趋化作用，可诱导IDC成熟，在体内与明胶一样具有强大的佐剂作用。虽然警报在结构上是不同的，但它们很快就会从白细胞颗粒或受损细胞中释放出来。此外，胃肠道、胃肠道和气管支气管树上的角质形成细胞或上皮细胞也可以对促炎症刺激作出反应，从而诱导警报器的产生。因此，Alarmins可能代表了一种早期预警系统，以提醒宿主防御危险信号。在前一年，我们还研究了另一种白细胞颗粒衍生的Alarmin的免疫激活和趋化作用，即嗜酸性粒细胞衍生神经毒素(EDN)，它是RNase家族的成员，具有抗病毒活性，包括抗HIV活性。EDN基于其与百日咳毒素敏感的GiPCR的相互作用，对IDC和MDC具有趋化作用。此外，基于与TLR2的相互作用，EDN可激活IDC产生多种促炎细胞因子，并成熟为MDC。EDN在体内也有很强的免疫刺激作用。然而，EDN以一种优先促进Th2极化的方式激活DC，B淋巴细胞诱导更多的IgG1抗体产生和IL-5和13的产生，而不是IL-4或IFNγ的产生。虽然EDN具有警报的特性，但这表明EDN的佐剂作用可能被证明在针对寄生虫病免疫的疫苗中比在肿瘤免疫中更有用。我们还证明了乳铁蛋白具有警报活性。我们使用人乳铁蛋白(TLF)的GMP制剂进行研究。TLF正在被其他中心评估为一种抗肿瘤疗法。TLF对单核细胞APC具有趋化作用，但使用一种未知的受体来招募和动员单核细胞。由于C3 H/HeJ不同于C3 H/HEN，小鼠不被TLF激活，提示TLR4参与了TLF的免疫佐剂作用。TLF活性似乎通过小鼠的胃肠道运输而存活下来。因此，我们正在调查TLF是否会加重IBD，以及摄入乳铁蛋白是否会因此使受试者易患结肠癌。在过去的一年里，我们鉴定了颗粒溶素，它通常储存在自然杀伤细胞(NK)和细胞毒性T细胞(CTL)的颗粒中，是一种警报蛋白。9 kDa和15 kDa两种形式的颗粒溶素对未成熟的髓系树突状细胞(IDC)具有趋化作用，可激活这些IDC成熟为抗原提呈树突状细胞(MDC)。颗粒溶素与一种未知的百日咳毒素敏感的GIα蛋白细胞受体(GiPCR)相互作用，诱导趋化反应。与TLF一样，颗粒溶素也不能诱导C3H/HeJ IDC成熟，提示TLR4参与了颗粒溶素的免疫激活作用。颗粒溶素的TLR4刺激作用与内毒素污染有关的可能性已被排除。因此，我们可以将NK和CTL细胞添加到嗜酸性粒细胞、粒细胞、上皮细胞和巨噬细胞中作为警报的来源。我们目前正在制备融合蛋白，这些融合蛋白由一些更有效的警示蛋白与几种不同的黑色素瘤肿瘤抗原融合而成，以获得有效的抗肿瘤疫苗。