评估近红外光免疫疗法靶向体外和体内表达成纤维细胞激活蛋白-α的细胞。
Evaluating near-infrared photoimmunotherapy for targeting fibroblast activation protein-α expressing cells in vitro and in vivo.
机构信息
Division of Cancer Imaging Research, The Russell H Morgan Department of Radiology and Radiological Science, Baltimore, Maryland, USA.
Laboratory of Molecular Theranostics Molecular Imaging Branch, NCI/NIH, Bethesda, Maryland, USA.
出版信息
Cancer Sci. 2023 Jan;114(1):236-246. doi: 10.1111/cas.15601. Epub 2022 Oct 21.
Photoimmunotherapy (PIT), carried out using an Ab conjugated to the near infrared dye IRDye700DX, is achieving significant success in target-specific elimination of cells. Fibroblast activation protein alpha (FAP-α) is an important target in cancer because of its expression by cancer-associated fibroblasts (CAFs) as well as by some cancer cells. Cancer-associated fibroblasts that express FAP-α have protumorigenic and immune suppressive functions. Using immunohistochemistry of human breast cancer tissue microarrays, we identified an increase of FAP-α CAFs in invasive breast cancer tissue compared to adjacent normal tissue. We found FAP-α expression increased in fibroblasts cocultured with cancer cells. In proof-of-principle studies, we engineered human FAP-α overexpressing MDA-MB-231 and HT-1080 cancer cells and murine FAP-α overexpressing NIH-3T3 fibroblasts to evaluate several anti-FAP-α Abs and selected AF3715 based on its high binding affinity with both human and mouse FAP-α. After conjugation of AF3715 with the phthalocyanine dye IR700, the resultant Ab conjugate, FAP-α-IR700, was evaluated in cells and tumors for its specificity and effectiveness in eliminating FAP-α expressing cell populations with PIT. Fibroblast activation protein-α-IR700-PIT resulted in effective FAP-α-specific cell killing in the engineered cancer cells and in two patient-derived CAFs in a dose-dependent manner. Following an intravenous injection, FAP-α-IR700 retention was three-fold higher than IgG-IR700 in FAP-α overexpressing tumors, and two-fold higher compared to WT tumors. Fibroblast activation protein-α-IR700-PIT resulted in significant growth inhibition of tumors derived from FAP-α overexpressing human cancer cells. A reduction of endogenous FAP-α murine CAFs was identified at 7 days after FAP-α-IR700-PIT. Fibroblast activation protein-α-targeted near infrared PIT presents a promising strategy to eliminate FAP-α CAFs.
光免疫疗法(PIT)使用与近红外染料 IRDye700DX 偶联的抗体进行,正在实现针对细胞的特异性消除的显著成功。成纤维细胞激活蛋白α(FAP-α)是癌症中的一个重要靶点,因为它在癌症相关成纤维细胞(CAFs)以及一些癌细胞中表达。表达 FAP-α 的 CAFs 具有促肿瘤和免疫抑制功能。通过对人乳腺癌组织微阵列的免疫组织化学分析,我们发现与相邻正常组织相比,浸润性乳腺癌组织中 FAP-α CAFs 增加。我们发现与癌细胞共培养的成纤维细胞中 FAP-α 表达增加。在原理验证研究中,我们构建了人 FAP-α 过表达 MDA-MB-231 和 HT-1080 癌细胞和鼠 FAP-α 过表达 NIH-3T3 成纤维细胞,以评估几种抗 FAP-α Ab,并基于其与人及鼠 FAP-α 的高结合亲和力选择 AF3715。AF3715 与酞菁染料 IR700 缀合后,所得抗体缀合物 FAP-α-IR700,在细胞和肿瘤中进行了评价,以评估其在 PIT 中特异性消除表达 FAP-α 的细胞群的效果。FAP-α-IR700-PIT 导致在工程化癌细胞和两种源自患者的 CAFs 中以剂量依赖性方式有效杀伤 FAP-α 特异性细胞。静脉注射后,FAP-α 过表达肿瘤中 FAP-α-IR700 的保留量是 IgG-IR700 的三倍,而与 WT 肿瘤相比则增加了两倍。FAP-α-IR700-PIT 导致 FAP-α 过表达人癌细胞来源的肿瘤生长显著抑制。在 FAP-α-IR700-PIT 后 7 天,鉴定到内源性 FAP-α 鼠 CAFs 的减少。FAP-α 靶向近红外 PIT 为消除 FAP-α CAFs 提供了一种有前途的策略。