Mechanism of IL-10 protective effect in development of childhood B cell acute lymphoblastic leukemia

项目摘要 尽管在了解与B-ALL相关的免疫系统异常方面取得了重大进展，但 与众不同的 这个应用的特点是从细胞免疫的角度来解决这个问题。我建议 这说明除了B细胞前体细胞的内源性突变外，非B细胞系免疫细胞也发挥着突出的作用 在B-ALL发展中的作用。B细胞前体细胞发生突变，作为对炎症刺激的直接反应； 然而，骨髓中含有其他免疫细胞群，可以改变肿瘤的发展。 对炎症的反应。 氮物种(ROS/RNS)诱导癌症相关突变。我假设抗肿瘤药物 IL-10在儿童B-ALL中的保护作用除了加速发展B-ALL外，Il10-/-TEL- AML1CDKN2a-/-小鼠有更多疲惫的、PD1 CD8记忆T细胞，也具有更高的特征 中性粒细胞水平高于IL10/TEL-AML1Ckdn2a-/-小鼠。目标1中的实验将扩大这一观察结果 以及白血病B细胞抑制自身免疫原性的能力，这是免疫逃避的一种机制。 其他实验也将跟踪CD8T细胞在白血病中的募集程度以及他们的 随后的细胞毒作用需要对IL-10有反应性。这些实验将提供一种生物 CD8 T细胞如何在IL-10介导的B-ALL保护中发挥作用。AIM 2中的研究将 确定IL10-/-TEL-AML1CDKN2a-/-小鼠中性粒细胞产生的ROS/RNS是否诱导更多的DNA 与Il10/tel-AML1 Ckdn2a相比，B祖细胞受损并导致B-ALL潜伏期缩短-/- 老鼠。将评估从IL10-/-和IL10/-分离的中性粒细胞的激活和ROS/RNS的产生 白血病。期望值 突变的总数和ROS/RNS相关的突变特征将在 在没有IL10的情况下形成的白血病B细胞。最后，我将确定中性粒细胞的升高 在白血病前期和白血病小鼠中具有特征的IL10-/-TEL-AML1CDKN2a-/-小鼠 加快B-ALL发展。拟议的研究结果将提供新的生物学见解。 研究出生时的免疫缺陷如何有助于儿童B-ALL的发展。此外，这项工作还具有 对于B-ALL。

Project Summary Despite significant advances in understanding immune system abnormalities associated with B-ALL, how the status of the immune system at birth contributes to leukemia development is unknown. The distinguishing feature of this application is the cellular immunity perspective from which this question is addressed. I propose that in addition to B-cell progenitor intrinsic mutagenesis, non-B lineage immune cells also play a prominent role in B-ALL development. B-cell progenitors develop mutations as a direct response to inflammatory stimuli; however, the bone marrow contains other immune cell populations that can alter tumor development in response to inflammation. For example, in solid cancers, low levels of the cytokine IL-10 elicit strong pro-tumor responses of CD8 T cells and neutrophils. Specifically, CD8 T cells lose their ability to detect and lyse tumor cells, whereas neutrophils become elevated in frequency and increase the potential for reactive-oxygen and - nitrogen species (ROS/RNS) to induce cancer-associated mutations. I hypothesize that the anti-tumor mechanisms of IL-10 in increasing CD8 T cell activity and suppressing neutrophils are involved in the protective role of IL-10 in childhood B-ALL. In addition to developing B-ALL at an accelerated rate, Il10-/- TEL- AML1 Cdkn2a-/- mice have more exhausted, PD1+ CD8 memory T cells and are also characterized by higher levels of neutrophils than Il10+/+ TEL-AML1 Ckdn2a-/- mice. Experiments in Aim 1 will extend this observation by testing the impact of Il10 loss on the cytotoxic activity of CD8 memory T cells directed to leukemic B cells and on the ability of leukemic B cells to suppress their own immunogenicity, a mechanism of immune evasion. Additional experiments will also track the extent to which the recruitment of CD8 T cells to leukemias and their subsequent cytotoxic activity requires responsiveness to IL-10. These experiments will provide a biological demonstration for how CD8 T cells can be a factor in IL-10 mediated protection in B-ALL. Studies in Aim 2 will determine if the ROS/RNS produced by neutrophils of Il10-/- TEL-AML1 Cdkn2a-/- mice induce more DNA damage in B progenitors and contribute to decreased B-ALL latency compared to Il10+/+ TEL-AML1 Ckdn2a-/- mice. Activation and ROS/RNS production will be assessed in neutrophils isolated from the Il10-/- and Il10+/+ leukemias. I will then determine how Il10 loss impacts the mutational landscape of leukemia. The expectation is that the total number of mutations and ROS/RNS-associated mutational signatures will be increased in the leukemic B cells that developed in the absence of Il10. Finally, I will determine if the elevation of neutrophils that is characterized in pre-leukemic and leukemic Il10-/- TEL-AML1 Cdkn2a-/- mice is required for the acceleration of B-ALL development. The results of the proposed research will provide new biological insights into how immune defects at birth contribute to the development of childhood B-ALL. Moreover, this work has the potential to identify immune responses that can be targeted for leukemia prevention in children at high risk for B-ALL.