**5. Conclusions**

TCL-mediated cancer immunotherapy has been shown to involve the activation of tumor-specific CD8<sup>+</sup> and CD4<sup>+</sup> T cells via a vast array of immunogenic epitopes. However,

an in-depth understanding of the physiological functions of DCs and in vivo interactions with other immune cell populations are needed to improve therapeutic effectiveness and establish optimal modulation in adaptive immunity. To emphasize the efficacy of TCLmediated anticancer therapy, we reviewed (1) various experimental methods for preparing TCLs as a major immunomodulatory source, (2) TCL-mediated augmentation in DC-T cell interaction, and the subsequently induced activation of T cells, and (3) the recent progress in the biomaterial-based in vivo administration of TCLs. With the aid of co-stimulatory adjuvants, biomaterial-mediated exogenous TCL delivery could be an efficient therapeutic strategy to enhance the stability and sustained release of cargo TCLs, improve the specificity of DC targeting, and activate DCs synergistically. As a result of sufficient DC activation (i.e., increased antigen presentation and cytokine release), antigen-specific T cell-mediated tumor suppression and vaccination can be upregulated through the dynamic interplay of immune responses. Therefore, exogenous TCL delivery techniques could be a promising treatment for enhancing the DC-mediated activation of adaptive immune responses, vaccination, and tumor-specific suppression.

**Funding:** This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2021R1A4A3024237, 2019R1A2C1084828, and 2017M3A7B8061942).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data presented in this study are contained within the article.

**Acknowledgments:** Not applicable.

**Conflicts of Interest:** The authors disclose no conflict of interest in this work.
