KIR and HLA in cis and trans cooperatively shape human NK education

项目摘要 自然杀伤（NK）细胞在造血干细胞移植（HCT）的环境中高度相关， 它们的活性可以大大降低白血病患者复发的风险。尽管捐助方取得了进展， 选择，以尽量减少移植并发症，白血病复发仍然是最具破坏性的原因之一 移植失败。目前普遍缺乏关于NK细胞群体如何被训练用于效应细胞的知识。 功能，白血病识别和清除。虽然已知HLA I类分子之间的相互作用 并且抑制性杀伤Ig样受体（KIR）对于NK教育或效应器功能的“许可”是重要的， 它们相互作用的方向，有助于它们相互作用强度的因素，以及相对的 供体和受体HLA的贡献是未知的。 基础人类NK研究的主要障碍是缺乏体内模型， 忠实地概括NK教育。显示HLA-B*27：05的人源化NOD-RAG 2 IL 2 R γc-/-小鼠品系 成功地允许成熟NK细胞的植入和功能性人NK细胞的发育， CD 34+干细胞。初步研究表明，在体内环境表达同源HLA教育， 开发和转移表达KIR的NK细胞，并提高其长期存活率。与此同时，FRET RNAi技术揭示了细胞固有的HLA和KIR之间的顺式相互作用也促进了NK细胞的增殖。 教育HLA分子可以从邻近细胞转移到NK细胞上的证据引起了 作为一种机制，反式HLA可以通过KIR顺式连接进行教育的研究。 骨髓嵌合体中HLA表达对造血或基质区室的限制 将有助于确定供体和受体HLA对NK许可和持久性的相对贡献。受体- 已知反式结合的配体对也以顺式相互作用，需要进一步澄清以了解如何 这些相互作用影响NK功能。顺式-反式结合之间的竞争将检验顺式 这种相互作用通过保护KIR免受反式HLA的连接而促进NK应答。NK细胞有和没有 将对非天然HLA表达进行功能性测试，以更好地了解棘红细胞增多症如何有助于NK细胞增殖。 在连续或中断暴露于同源HLA后进行教育。最后，实验结果从 人源化小鼠模型和体外研究将使用获得的NK细胞在全人系统中进行验证。 来自接受HLA不匹配的脐带血移植的患者。 这些目标将促进我们对NK教育的基本分子要求的理解 和获得效应器功能。更深入地了解HLA在顺式和反式中提供的许可， 在造血细胞移植和过继性NK细胞疗法中选择供者， 癌

PROJECT SUMMARY Natural Killer (NK) cells are highly relevant in the setting of hematopoietic stem cell transplantation (HCT), where their activity can drastically reduce the risk of relapse in leukemia patients. Despite advances in donor selection to minimize transplant complications, leukemia relapse remains one of the most devastating causes of transplant failure. There is a general lack of knowledge of how NK cell populations are educated for effector function, leukemia recognition and clearance. While it is known that interaction between HLA class I molecules and the inhibitory killer Ig-like receptors (KIR) are important for NK education or “licensing” for effector function, the orientation of their interaction, the factors that contribute to the strength of their interaction, and the relative contributions of donor and recipient HLA are not known. A major impediment to fundamental human NK studies has been the lack of in vivo models that faithfully recapitulate NK education. A humanized NOD-RAG2IL2Rγc-/- mouse strain that exhibits HLA-B*27:05 successfully permits engraftment of mature NK cells and development of functional human NK cells from CD34+ stem cells. Preliminary investigations reveal that in vivo environments expressing cognate HLA educate developing and transferred KIR-expressing NK cells and enhance their long-term survival. In parallel, FRET and RNAi technology reveals that cis-interaction between HLA and KIR intrinsic to the cell also facilitates NK education. Evidence that HLA molecules can be transferred onto NK cells from adjacent cells provokes investigation of trogocytosis as a mechanism by which trans HLA may permit education via cis ligation of KIR. Restriction of HLA expression to the hematopoietic or stromal compartments in bone marrow chimeras will help define the relative contributions of donor and recipient HLA to NK licensing and persistence. Receptor- ligand pairs known to bind in trans also interact in cis, and further clarification is required to understand how these interactions influence NK function. Competition between cis-trans binding will test the hypothesis that cis interactions facilitate NK responsiveness by shielding KIR from ligation of trans HLA. NK cells with and without non-native HLA expression will be functionally tested to better understand how trogocytosis contributes to NK education after continuous or interrupted exposure to cognate HLA. Finally, experimental findings from the humanized mouse model and in vitro studies will be verified in a fully human system using NK cells obtained from patients who have received an HLA-mismatched umbilical cord blood transplant. These goals will advance our understanding of fundamental molecular requirements for NK education and acquisition of effector function. A deeper understanding of licensing by HLA provided in cis and trans will inform donor selection in hematopoietic cell transplantation and adoptive NK cell therapies for the treatment of cancer.