Abstract:
UNASSIGNED: Spontaneously occurring glioma in pet dogs is increasingly recognized as a valuable translational model for human glioblastoma. Canine high grade glioma and human glioblastomas share many molecular similarities, including accumulation of immunosuppressive regulatory T cells (Tregs) that inhibit anti-tumor immune responses. Identifying in dog mechanisms responsible for Treg recruitment may afford targeting the cellular population driving immunosuppression, the results providing a rationale for translational clinical studies in human patients. Our group has previously identified C-C motif chemokine 2 (CCL2) as a glioma-derived T-reg chemoattractant acting on chemokine receptor 4 (CCR4) in a murine orthotopic model of glioma. Recently, we demonstrated a robust increase of CCL2 in the brain tissue of canine patients bearing high-grade glioma.
UNASSIGNED: We performed a series of in vitro experiments using canine Tregs and patient-derived canine glioma cell lines (GSC 1110, GSC 0514, J3T-Bg, G06A) to interrogate the CCL2-CCR4 signaling axis in the canine.
UNASSIGNED: We established a flow cytometry gating strategy for identification and isolation of FOXP3+ Tregs in dogs. The canine CD4 + CD25high T-cell population was highly enriched in FOXP3 and CCR4 expression, indicating they are bona fide Tregs. Canine Treg migration was enhanced by CCL2 or by glioma cell line-derived supernatant. Blockade of the CCL2-CCR4 axis significantly reduced migration of canine Tregs. CCL2 mRNA was expressed in all glioma cell lines and expression increased when exposed to Tregs but not to CD4 + helper T-cells.
UNASSIGNED: Our study validates CCL2-CCR4 as a bi-directional Treg-glioma immunosuppressive and tumor-promoting axis in canine high-grade glioma.
摘要:
目的:宠物狗自发性神经胶质瘤越来越被认为是人类胶质母细胞瘤的一种有价值的转化模型。犬高级别神经胶质瘤和人类胶质母细胞瘤有许多分子相似性,包括抑制抗肿瘤免疫应答的免疫抑制调节性T细胞(Tregs)的积累。识别负责Treg募集的狗机制可能会靶向驱动免疫抑制的细胞群,该结果为人类患者的转化临床研究提供了理论基础。我们小组先前已将C-C基序趋化因子2(CCL2)鉴定为神经胶质瘤衍生的T-reg化学引诱物,在鼠神经胶质瘤原位模型中作用于趋化因子受体4(CCR4)。最近,我们证明了患有高级别神经胶质瘤的犬患者的脑组织中CCL2的强劲增加。方法我们使用犬Tregs和患者来源的犬神经胶质瘤细胞系(GSC1110,GSC0514,J3T-Bg,G06A)以询问犬科动物的CCL2-CCR4信号轴。结果我们建立了流式细胞术门控策略来鉴定和分离狗中的FOXP3+Treg。犬CD4+CD25高T细胞群高度富集FOXP3和CCR4表达,表明他们是真正的Tregs.CCL2或神经胶质瘤细胞系来源的上清液增强了犬Treg的迁移。CCL2-CCR4轴的阻断显著降低了犬Treg的迁移。CCL2mRNA在所有神经胶质瘤细胞系中均表达,当暴露于Tregs而不是CD4辅助T细胞时,表达增加。结论我们的研究证实CCL2-CCR4是犬高级别神经胶质瘤中双向的Treg-神经胶质瘤免疫抑制和促进肿瘤的轴。