In Situ Reprogramming of Tumor‐Associated Macrophages with Internally and Externally Engineered Exosomes

Abstract

The reprogramming of tumor‐associated macrophages (TAMs) has emerged as an efficient strategy for immunotherapy. However, most of the approaches did not allow the in situ reprogramming of TAM because their low efficiency, non‐specificity, or potential side effects. Herein, we produced exosomes with the clustered regularly interspaced short palindromic repeats interference (CRISPRi) internally engineered and the TAM specific peptide externally engineered onto the exosome membrane. The internally and externally engineered exosomes (IEEE, also named as I3E) allowed the selective homing to tumor tissue and targeted to M2‐like TAMs, which nearly repressed the expression of PI‐3 kinase gamma (PI3Kγ) completely, and induced the TAMs polarizing to M1 both in vitro and in vivo. The polarized M1 macrophages awakened the “hot” tumor‐immunity, causing the increase of T lymphocyte infiltration and the decrease of myeloid‐derived suppressor cells, and inhibiting the tumor growth significantly. I3E reprogramed TAMs in situ precisely and efficiently.

CRISPR/Cas gene editing and delivery systems for cancer therapy

“…(B) I3E reprogrammed the TAMs and stimulated macrophage‐based immunity. Reproduced with permission from Zhang et al (2023). Copyright 2023.…”

“…In addition to directly loading the CRISPR systems with exosomes, exosomes can also be engineered to develop more functions. Jiang and colleagues produced engineered exosomes, which were generated from internally engineered HEK293T cell line with CRISPRi for high expression of peptides on the surface allowed the selective homing to tumor tissue and targeted to M2‐like tumor‐associated macrophages (Figure 10f; Zhang et al, 2023). The engineered exosomes coated on the nuclear‐targeted nanoparticle which formed by mixing the nuclear localization signal modified Poly‐β amino ester (PBAE) with CRISPR/dCas9 system plasmids targeting PI‐3 kinase gamma (PI3K γ ) to result the construction of I3E.…”

Nanotechnology‐based CRISPR/Cas9 delivery system for genome editing in cancer treatment

“…Jiang and coworkers synthesized an amino group ended and NLS modified PBAE to complex a CRISPRi/dCas9 plasmid targeting PI‐3 kinase gamma ( PI3Kγ ) gene (NPC) (Figure 4E). 136 A second coating of CRV‐expressing exosome membranes (CRV‐EM) made from human embryonic kidney (HEK) 293 T cells was applied to the NPC, in which CRV selectively targeted to TAMs. The internally and externally engineered exosomes (IEEE) enabled the preferential migration to tumor site as well as targeting M2‐TAMs.…”

Engineering of M2 Macrophages‐Derived Exosomes via Click Chemistry for Spinal Cord Injury Repair

“…In contrast, exosomes can safely deliver bioactive agents into macrophages due to their superior biocompatibility. [ 17 ] Considering these factors, application of MEX seems to be an ideal agent for the treatment of inflammatory diseases such as SCI.…”