*Review* **Activation of Cellular Players in Adaptive Immunity via Exogenous Delivery of Tumor Cell Lysates**

**Jihyun Seong and Kyobum Kim \***

Department of Chemical and Biochemical Engineering, Dongguk University, 30 Pildong-ro 1-gil, Jung-gu, Seoul 22012, Korea; jh.seong520@gmail.com

**\*** Correspondence: kyobum.kim@dongguk.edu; Tel.: +82-2-2260-8597

**Abstract:** Tumor cell lysates (TCLs) are a good immunogenic source of tumor-associated antigens. Since whole necrotic TCLs can enhance the maturation and antigen-presenting ability of dendritic cells (DCs), multiple strategies for the exogenous delivery of TCLs have been investigated as novel cancer immunotherapeutic solutions. The TCL-mediated induction of DC maturation and the subsequent immunological response could be improved by utilizing various material-based carriers. Enhanced antitumor immunity and cancer vaccination efficacy could be eventually achieved through the in vivo administration of TCLs. Therefore, (1) important engineering methodologies to prepare antigen-containing TCLs, (2) current therapeutic approaches using TCL-mediated DC activation, and (3) the significant sequential mechanism of DC-based signaling and stimulation in adaptive immunity are summarized in this review. More importantly, the recently reported developments in biomaterial-based exogenous TCL delivery platforms and co-delivery strategies with adjuvants for effective cancer vaccination and antitumor effects are emphasized.

**Keywords:** tumor cell lysate; adjuvant; dendritic cell; exogenous delivery system; cancer immunotherapy
