Abstract

Background

The ovarian tumour microenvironment is an abundant source of tumour-infiltrating lymphocytes (TILs) which can be readily harnessed for infusion in the context of adoptive TIL therapy. This strategy has been proven feasible, but it appears clinically ineffective in ovarian cancer patients due to the absence of tumour-reactive TILs and the presence of immunosuppression. Hence, we hypothesized that an oncolytic adenovirus expressing Tumour Necrosis Factor (TNF)-alpha(a) and Interleukin (IL)-2 (Ad5/3-E2F-D24-hIL-2-IRES-TNFa; TILT-123) could overcome this by generating a proinflammatory microenvironment and reinvigorating TIL anti-tumour activity.

Methods

Fresh explants from metastatic or primary tumour sites were obtained from stage III-IV ovarian cancer patients and short-term cultures were established in the absence or presence of oncolytic adenovirus. The remainder of the tumour explant was used to generate clinically relevant TILs which were co-cultured with autologous T cell-depleted single cell suspensions pre-treated with or without oncolytic adenoviruses. Cytokine content changes and TIL reactivity was assessed during culture by flow cytometry or interferon (IFN) gamma(g) enzyme-linked immune sorbent assay.

Results

Treatment of short-term cultures with oncolytic adenovirus coding for TNFa and IL-2 introduced profound changes within the microenvironment, which were characterized by an increase in proinflammatory cytokines and decrease in suppressive cytokines. Further benefits were seen in T-cell depleted ovarian cancer single-cell suspensions infected with cytokine-coding oncolytic adenovirus, which enabled significant production of IFNg by autologous TILs. Such levels were not seen in co-cultures where no virus or the backbone oncolytic adenovirus (no cytokine transgenes) was added.

Conclusion

These data illustrate the potential of oncolytic adenovirus coding for TNFa and IL-2 to rewire the ovarian tumour microenvironment for effective TIL anti-tumour reactivity. This approach may improve the efficacy of adoptive TIL therapy in ovarian cancer patients, thus warranting further clinical investigation.

Legal entity responsible for the study

TILT Biotherapeutics Ltd.

Funding

TILT Biotherapeutics Ltd.

Disclosure

J.M. Santos: Full / Part-time employment: TILT Biotherapeutics Ltd. V. Cervera-Carrascon: Full / Part-time employment: TILT Biotherapeutics Ltd. M. Siurala: Full / Part-time employment: TILT Biotherapeutics Ltd. T. de Gruijl: Advisory / Consultancy: TILT Biotherapeutics Ltd. A. Hemminki: Shareholder / Stockholder / Stock options, Full / Part-time employment, Officer / Board of Directors: TILT Biotherapeutics Ltd. All other authors have declared no conflicts of interest.

中文翻译：

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149P用溶瘤腺病毒改造卵巢肿瘤微环境可增强肿瘤浸润淋巴细胞的抗肿瘤活性

抽象的

背景

卵巢肿瘤微环境是肿瘤浸润淋巴细胞（TIL）的丰富来源，在过继TIL治疗的背景下，可以很容易地利用它们进行输注。该策略已被证明是可行的，但由于缺乏肿瘤反应性TIL和存在免疫抑制作用，因此在卵巢癌患者中临床上似乎无效。因此，我们假设表达肿瘤坏死因子（TNF）-α（a）和白介素（IL）-2（Ad5 / 3-E2F-D24-hIL-2-IRES-TNFa; TILT-123）的溶瘤腺病毒可以克服通过产生促炎性微环境并增强TIL抗肿瘤活性来实现这一点。

方法

来自转移性或原发性肿瘤部位的新鲜外植体来自III-IV期卵巢癌患者，并且在不存在或存在溶瘤性腺病毒的情况下建立了短期培养物。肿瘤外植体的其余部分用于产生临床相关的TIL，其与用或不用溶瘤性腺病毒预处理的自体T细胞耗尽的单细胞悬浮液共培养。在培养过程中，通过流式细胞仪或干扰素（IFN）γ（g）酶联免疫吸附测定法评估了细胞因子含量的变化和TIL反应性。

结果

用编码TNFα和IL-2的溶瘤腺病毒治疗短期培养物，在微环境中引入了深刻的变化，其特征在于促炎性细胞因子的增加和抑制性细胞因子的减少。在用细胞因子编码溶瘤性腺病毒感染的T细胞耗竭的卵巢癌单细胞悬液中看到了进一步的好处，这使自体TIL能够大量产生IFNg。在没有添加病毒或主链溶瘤性腺病毒（无细胞因子转基因）的共培养物中，未观察到这样的水平。

结论

这些数据说明了溶瘤腺病毒编码TNFa和IL-2可能重新连接卵巢肿瘤微环境以实现有效的TIL抗肿瘤反应性。这种方法可能会提高卵巢癌患者中过继性TIL治疗的疗效，因此值得进行进一步的临床研究。

负责研究的法人实体

蒂尔生物疗法有限公司

资金

蒂尔生物疗法有限公司

揭露

JM Santos：全职/兼职：TILT Biotherapeutics Ltd. V. Cervera-Carrascon：全职/兼职：TILT Biotherapeutics Ltd. M. Siurala：全职/兼职：TILT Biotherapeutics Ltd. T. de Gruijl ：咨询/顾问：TILT Biotherapeutics Ltd. A. Hemminki：股东/股东/股票期权，全职/兼职，官员/董事会：TILT Biotherapeutics Ltd.所有其他作者均声明没有利益冲突。