T-cell Responses in the Microenvironment of Primary Renal Cell Carcinoma—Implications for Adoptive Cell Therapy

Abstract

expansion of large numbers of highly potent tumor-reactive T cells appears a prerequisite for effective adoptive cell therapy (ACT) with autologous tumor-infiltrating lymphocytes (TIL) as shown in metastatic melanoma (MM). We therefore sought to determine whether renal cell carcinomas (RCC) are infiltrated with tumor-reactive T cells that could be efficiently employed for adoptive transfer immunotherapy. TILs and autologous tumor cell lines (TCL) were successfully generated from 22 (92%) and 17 (77%) of 24 consecutive primary RCC specimens and compared with those generated from metastatic melanoma. Immune recognition of autologous TCLs or fresh tumor digests was observed in CD8 TILs from 82% of patients (18/22). Cytotoxicity assays confirmed the tumoricidal capacity of RCC-TILs. The overall expansion capacity of RCC-TILs was similar to MM-TILs. However, the magnitude, polyfunctionality, and ability to expand in classical expansion protocols of CD8 T-cell responses was lower compared with MM-TILs. The RCC-TILs that did react to the tumor were functional, and antigen presentation and processing of RCC tumors was similar to MM-TILs. Direct recognition of tumors with cytokine-induced overexpression of human leukocyte antigen class II was observed from CD4 T cells (6/12; 50%). Thus, TILs from primary RCC specimens could be isolated, expanded, and could recognize tumors. However, immune responses of expanded CD8 RCC-TILs were typically weaker than MM-TILs and displayed a mono-/oligofunctional pattern. The ability to select, enrich, and expand tumor-reactive polyfunctional T cells may be critical in developing effective ACT with TILs for RCC. In summary, TILs isolated from primary RCC specimens could recognize tumors. However, their immune responses were weaker than MM-TILs and displayed a mono-/oligofunctional pattern. The ability to select and expand polyfunctional T cells may improve cell therapy for RCC. .

Local Irradiation Sensitized Tumors to Adoptive T Cell Therapy via Enhancing the Cross-Priming, Homing, and Cytotoxicity of Antigen-Specific CD8 T Cells

“…The first study of adoptive T cell therapy was performed by Rosenberg et al, and the results showed that TILs can be effective against metastatic melanoma (9). Until now, adoptive T cell therapy has been conducted in a variety of tumor types, including renal cell cancer (10), cervical cancer (11), and non-small cell lung cancer (12). Although promising results have been shown in some clinical trials, adoptive T cell therapy still faces some challenges in treating solid tumors.…”

Tumor-Infiltrating T Cells From Clear Cell Renal Cell Carcinoma Patients Recognize Neoepitopes Derived From Point and Frameshift Mutations

“…Tumor-infiltrating lymphocytes (TILs), tumor fragments (TFs), and tumor cell lines (TCLs) from ccRCC patients were obtained at the Department of Oncology and Center for Cancer Immune Therapy, Copenhagen University Hospital, Denmark, under approval by the Ethics Committee of the Capital Region of Denmark and the Danish Data Protection Agency. Young TIL cultures were obtained from resected tumor lesions from individuals with ccRCC with a Fuhrman grade between 1 and 3 (23). Tumor lesions were resected following surgical removal, and TFs were cultured individually in complete medium [RPMI1640 + GlutaMAX TM (Gibco, cat#61870010) with 10% human serum (Sigma-Aldrich, cat#H3667), 100 U/ml penicillin (P/S, Sigma-Aldrich, cat#P0781), 100 µg/ml streptomycin (P/S, Sigma-Aldrich, cat#P0781), 1.25 µg/ml fungizone (Bristol-Myers Squibb), and 6,000 U/ml IL-2 (Proleukin, Novartis, cat#200-02)] at 37 • C and 5% CO 2 , allowing TILs to migrate into the medium.…”

“…ccRCCs appear to be immune sensitive, as suggested by high levels of T cells infiltrating the tumor site (17), and clinical benefit can be achieved using cytokine-based immunotherapies with interferon-α and high-dose interleukin 2 (18,19) and checkpoint inhibitors (20,21). Nevertheless, the tumor microenvironment of ccRCCs is characterized as highly immunosuppressive (22), which is reflected by the poor functional quality of T cell responses observed, with implications for adoptive cell therapy (23).…”

“…Such investigation is critical for using neoantigens as therapeutic targets and biomarkers of relevance to immunotherapy in this cancer type. For that reason, we evaluated the T cell recognition of neopeptides predicted from SNVs, in-frame, and frameshift indels in six ccRCC patients previously described in (23). The prediction was performed with WES from two sources of tumor material (TCL and TF) to include all potential neopeptides in our screenings.…”

Adoptive Cell Therapy—Harnessing Antigen-Specific T Cells to Target Solid Tumours

“…One of the reasons of a relatively modest therapeutic effect might be a low frequency (3%) of tumour-reactive T cells in ex vivo expanded TIL cultures [95]. Functional characterisation of expanded TILs from renal cell carcinoma and gastrointestinal cancer (GI) also revealed lower frequency of tumour-specific T cells compared to melanoma [96,97]. This can be an effect of relatively low mutational burden of aforementioned tumours and in consequence their low immunogenicity.…”