IN SITU ANTITUMOR IMMUNITY AND EFFECTS OF RADIATION

本研究的目的是确定：（1）为什么细胞的 宿主免疫系统通常不能对 肿瘤细胞，即使这些细胞带有可识别的明显肿瘤 抗原;和（2）辐射对宿主肿瘤细胞的影响 交互. 这项研究的重点是细胞间的相互作用发生 不同类型的宿主细胞之间以及宿主细胞和肿瘤细胞之间， 在实际肿瘤中原位，我们已经证实包含许多 肿瘤反应性宿主免疫细胞。 我们用多细胞肿瘤 EMT 6/Ro乳腺肉瘤细胞的球体，相对免疫原性的BALB/c 小鼠肿瘤和1号线细胞，弱免疫原性BALB/c肺泡 研究宿主免疫细胞识别肿瘤的能力 抗原，浸润肿瘤，并在肿瘤样 微环境 介绍了离心淘洗技术， 免疫荧光流式细胞术用于分离、鉴定和 纯化原位宿主细胞的亚群。 我们已经确定 EMT 6肿瘤细胞分泌一种可溶性因子，其高度抑制肿瘤细胞增殖， 宿主免疫细胞，可能是一种机制，使这种肿瘤， 逃避免疫系统。 （IP）

The objectives of this research are to determine: (1) why cells of the host immune system are often unable to mount an effective response against tumor cells even when those cells bear recognizable distinct tumor antigens; and (2) the effect of radiation on the host-tumor-cell interactions. This study focuses on the cellular interactions occurring between various types of host cells and between host and tumor cells in situ within the actual tumor, which we have confirmed to contain many tumor-reactive host immune cells. We are using multicellular tumor spherolds of EMT6/Ro mammary sarcoma cells, a relatively immunogenic BALB/c mouse tumor, and Line 1 cells, a weakly immunogenic BALB/c alveolar carcinoma, to study the ability of host immune cells to recognize tumor antigens, infiltrate tumors, and function within a tumor-like microenvironment. The technologies of centrifugal elutriation and immunofluorescent flow cytometry are being used to separate, identify, and purify the subpopulations of in situ host cells. We have determined that EMT6 tumor cells secrete a soluble factor which is highly suppressive to host immune cells and is probably a mechanism which allows this tumor to evade the immune system. (IP)