ADENOVIRUS FLT3 LIGAND INDUCES NALT DCs FOR SALIVARY GLAND S-lgA Ab RESPONSES

描述（申请人提供）：在过去的五年中，我们研究了诱导和调节唾液分泌免疫球蛋白（S-lgA）抗体（Ab）反应的先天因子和免疫细胞。我们已经证明，编码flt3配体（FL）、淋巴蛋白（LTN）、RANTES和MCP-1 cDNA以及未甲基化的胞嘧啶-鸟嘌呤二核苷酸寡脱氧核苷酸（CpG ODN）的质粒，当用作鼻佐剂时，可以增强粘膜和全身免疫反应。给予这些鼻腔cDNA佐剂的小鼠鼻咽相关淋巴网状组织（NALT）和下颌下腺（SMGs）显示树突状细胞（dc）数量增加，这是诱导唾液S-lgA抗体反应的关键因素。此外，我们最近的研究使用表达FL cDNA （pFL）的腺病毒（Ad）作为鼻佐剂，显著增强了唾液S-lgA抗体的应答。基于这些发现，我们在此更新应用中的总体假设是NALT dc通过加工Ag然后迁移到smg来调节唾液S-lgA抗体反应。更具体地说，我们假设用基于fl的佐剂靶向NALT会优先诱导NALT dc向SMGs迁移，并增强粘膜S-lgA抗体反应的诱导。我们最近的研究表明，当用tlag加天然霍乱毒素鼻腔免疫小鼠时，T细胞独立（Tl） Ag特异性唾液S- IgA抗体反应与SMGs中B-1 B细胞数量增加相关。此外，研究人员还发现，鼻腔注射tlag的小鼠SMGs中有78个T细胞的toll样受体4 （TLR4）表达水平升高。这些结果清楚地表明，先天型和获得型免疫细胞之间的串音在诱导ag特异性唾液S-lgA抗体应答中是重要的，即使是对Tl ag的免疫应答。我们假设，以fl为基础的佐剂靶向NALT可诱导NALT dc向SMGs迁移，SMGs与B-1 B细胞和y& T细胞相互作用，诱导粘膜S-lgA抗体反应。为了检验我们的假设，我们提出了四个具体目标。我们将：1)通过ad - fl诱导的CD11b+ dc在NALT中趋化因子受体的表达特征及其成熟和重新定位到SMGs的过程。2)追踪ad - fl诱导的NALT DC迁移诱导唾液S-lgA抗体反应。3) Ad- fl诱导的NALT和SMG dc在诱导CD4'1' Th1和th2型细胞因子反应和持久记忆功能方面的免疫功能比较。4)确定ad - fl诱导的唾液dc、B-1 B细胞和yS T细胞对唾液S-lgA抗体应答的串扰精确机制。

DESCRIPTION (provided by applicant): Over the past five years, we have studied the innate factors and immune cells which induce and regulate salivary secretory immunoglobulin (S-lgA) antibody (Ab) responses. We have shown that plasmids encoding the flt3 ligand (FL), lymphotactin (LTN), RANTES and MCP-1 cDNA as well as unmethylated cytosine-guanine dinucleotides oligodeoxynucleotide (CpG ODN), when used as nasal adjuvants, enhance both mucosal and systemic immune responses. Nasopharyngeal-associated lymphoreticular tissues (NALT) and the submandibular glands (SMGs) from mice given these nasal cDNA adjuvants showed increased numbers of dendritic cells (DCs) and were a key factor in the induction of salivary S-lgA Ab responses. Further, our recent study using an adenovirus (Ad) expressing FL cDNA (pFL) when used as nasal adjuvant significantly enhanced salivary S-lgA Ab responses. Based upon these findings, our overall hypothesis in this renewal application is that NALT DCs regulate salivary S-lgA Ab responses by processing Ag followed by their migration into the SMGs. More specifically, we hypothesize that targeting NALT with FL-based adjuvants will preferentially induce migration of NALT DCs into the SMGs and enhance the induction of mucosal S-lgA Ab responses. Our recent study showed that T cell-independent (Tl) Ag-specific salivary S- IgA Ab responses correlated with an increased number of B-1 B cells in the SMGs when mice were immunized nasally with Tl Ag plus native cholera toxin. Further, we found that increased levels of Toll-like receptor four (TLR4) expression by 78 T cells in the SMGs of mice given nasal Tl Ag. These results clearly showed that cross-talk between innate- and acquired-type immune cells was important in the induction of Ag-specific salivary S-lgA Ab responses even for immune responses to Tl Ags. We hypothesize that targeting NALT with FL-based adjuvants induce migration of NALT DCs to the SMGs that interact with B-1 B cells and y& T cells in the SMGs for the induction of mucosal S-lgA Ab responses. In order to test our hypothesis, we propose four Specific Aims. We will: 1) Characterization of chemokine receptor expression by Ad-FL-induced CD11b+ DCs in NALT for their maturation and their relocation into the SMGs. 2) Tracking Ad-FL-induced NALT DC migration for the induction of salivary S-lgA Ab responses. 3) Comparison of Ad- FL-induced NALT and SMG DCs for their immunological function in the induction of CD4'1' Th1- and Th2-type cytokine responses as well as long-lasting memory function. 4) Determination of the precise mechanism for cross-talk between Ad-FL-induced salivary DCs, B-1 B cells and yS T cells for salivary S-lgA Ab responses.