Cervical cancer is the fourth most common malignancy in women, (Yue et al., 2023) with an estimated annual incidence of approximately 560,000 cases and 310,000 deaths worldwide (Bray et al., 2018). The majority of cervical cancers are caused by chronic infection with high-risk strains of the human papillomavirus (HPV), (Schiffman et al., 2011) (Doorbar et al., 2012). Despite the availability of HPV vaccines for children and young women, cervical cancer remains a leading cause of morbidity and mortality among adults already infected with HPV (Serrano et al., 2018). In addition to cervical cancer, HPV infection is also associated with other related cancers such as penile, vaginal, vulvar and oropharyngeal cancers (De Martel et al., 2017). To date, over 200 subtypes of HPV have been identified, (Bravo and Félez-Sánchez, 2015) which can be classified into into high-risk (oncogenic) and low-risk (non-oncogenic) types based on their association with cervical cancer (Kostareli et al., 2012). Notably, HPV16 and HPV18 emerge as the two most prevalent high-risk subtypes responsible for cervical cancer (Wheeler et al., 2009). Chronic infection with high-risk HPV strains can lead to cancer, whereas low-risk HPV infection often results in debilitating non-cancerous conditions, (Cutts et al., 2007; Doorbar et al., 2015)

The HPV virus belongs to the non-enveloped Papovaviridae family. The genome of HPV consists of a single molecule of circular double-stranded circular DNA, with all Open Reading Frame (ORF) protein-coding sequences confined to one strand (Okunade, 2020). The HPV genome is structured into three distinct regions: the early gene coding region (E), the late gene coding region (L), and the upstream regulatory region (URR). These three regions collectively contain eight ORFs, encoding eight proteins. Among them, E6 and E7 are the main oncogenic proteins, (Taberna et al., 2017; Pal and Kundu, 2019) (Tomaić, 2016). Integration of the E6 and E7 genes into the human genome is considered a key event in the development of cervical cancer. E6 binds to P53 and promotes its degradation, whereas the E7 binds to pRb and disrupts its complex formation with E2F transcription factors, leading to dysregulated cell cycle and cancer development (Leemans et al., 2011). Therefore, E6 and E7 are potential targets for therapeutic interventions (Magaldi et al., 2012). However, the development of drugs targeting E6 or E7 is challenging due to the lack of specific binding sites for small molecules.

T cell receptor (TCR) recognizes epitopes presented by the major histocompatibility complex (MHC) (or human leukocyte antigen, HLA, in human), initiating the “first” signal for T cell activation (Morishima et al., 2007). TCR gene-engineered T cells (TCR-T) have emerged as a promising immune-therapeutic approach and have demonstrated substantial tumor regression in various cancer types, especially solid tumors such as synovial cell cancer, multiple myeloma, and HPV-positive epithelial cancer. These engineered TCR-T cells are designed to target a diverse array of tumor antigens, including MART-1, NY-ESO-1, MAGE-A4, etc, (Johnson et al., 2009), (Robbins et al., 2011), (Rapoport et al., 2015) (Nagarsheth et al., 2021). In 2022, the United States Food and Drug Administration (US FDA) granted approval for the first TCR-based drug, KIMMTRAK (tebentafusp), for the treatment of unresectable or metastatic uveal melanoma, initiating an era for the development of TCR-based therapeutics for cancer immunotherapy.

T cell epitopes derived from HPV-E6 or E7 can be presented on the surface of tumor cells by HLA and recognized by TCRs on T cells, facilitating immune clearance of tumor cells. TCR-T cells targeting HPV16 E629–38 in the context of HLA-A*02:01 demonstrated significant tumor regression in patients with HPV-associated epithelial carcinoma, with 2 out of 12 patients showing objective tumor responses (Draper et al., 2015). A case report detailing a patient with three lung metastases revealed partial regression in two tumors and complete regression in one tumor (Doran et al., 2019). Clinical investigations involving TCR-T cells engineered to target HPV16 E711–19 in the context of HLA-A*02:01 demonstrated objective tumor responses in 6 out of 12 patients, with 3 patients experiencing complete regression of one or more tumors (Zhou et al., 2015). Currently, clinical investigations of HPV-E7 specific TCR-T cells have primarily focused on the context of HLA-A*02:01. However, it is noteworthy that HLA-A*11:01 stands out as one of the most prevalent HLA Class I subtypes and holds the highest frequency allele in China (Bendle et al., 2010).

The identification of specific T cells is challenging due to the notably low frequency of antigen-specific T cells in peripheral blood and the inhibitory immune microenvironment. Additionally, the introduction of exogenous human TCRs may lead to mismatches with endogenous TCRs within T cells, potentially resulting in the formation of self-reactive TCRs and triggering a fatal immune response (Zhang et al., 2021). To address these challenges, the utilization of murine TCRs sourced from HLA transgenic mice emerges as a promising strategy. Murine TCRs have not undergone negative selection in the human thymus and are less prone to developing immune tolerance toward human tumor-associated antigens. Moreover, the likelihood of mismatched pairing with endogenous TCRs is much lower compared to human TCRs.

In this study, we identified HPV-E7 specific TCRs from HLA-A*11:01 transgenic mice. Our analysis revealed these TCRs to be functionally competent, indicating their potential as promising candidates for tumor immunotherapy.