Cell-based therapeutics for the treatment of hematologic diseases inside the bone marrow

Targeted Delivery of c(RGDfk)-Modified Liposomes to Bone Marrow Through In Vivo Hitchhiking Neutrophils for Multiple Myeloma Therapy

Multiple myeloma (MM) is a prevalent bone marrow disorder. The challenges in managing MM include selecting chemotherapy regimens that effectively modulate the myeloma microenvironment and delivering them to the bone marrow with high efficacy and minimal toxicity. Herein, a novel bone marrow targeting strategy using c(RGDfk) peptide-modified liposomes loaded with chemotherapeutics is developed, which can specifically recognize and hitchhike neutrophils following systemic administration, capitalizing on their natural aging process to facilitate precise drug delivery to the bone marrow, thus minimizing off-target effects. On the one hand, c(RGDfk)-functionalized liposomes containing carfilzomib (CRLPs) successfully transformed macrophages from M2 phenotype to M1 phenotype, enhancing immunotherapeutic responses. On the other hand, c(RGDfk)-functionalized liposomes encapsulating BMS-202 (BRLPs), a small molecule checkpoint inhibitor, interrupted the PD-1/PD-L1 axis and promoted the infiltration of cytotoxic T cells. The co-administration of CRLPs and BRLPs successfully delivered drugs to bone marrow, leading to significant modulation of the myeloma microenvironment, reduced tumor growth, and improved survival time of MM-bearing mouse models. These findings introduced an alternative approach to modulating the myeloma microenvironment and underscored the efficacy of hitchhiking neutrophils for bone marrow drug delivery. This strategy show advantages over traditional drug delivery methods in terms of improved efficacy and lowered toxicity.

Silver nanoclusters show advantages in macrophage tracing in vivo and modulation of anti-tumor immuno-microenvironment

Macrophage-based nanomedicine represents an emerging powerful strategy for cancer therapy. Unfortunately, some obstacles and challenges limit the translational applications of macrophage-mediated nanodrug delivery system. For instance, tracking and effective cell delivery for targeted tumor sites remain to be overcome, and controlling the states of macrophages is still rather difficult due to their plastic nature in response to external stimuli. To address these critical issues, here, we reported a novel type of silver nanoclusters (AgNCs) with excellent fluorescent intensity, especially long-lasting cell labeling stability after endocytosis by macrophages, indicating promising applications in tracking macrophage-based nanomedicine delivery. Our mechanistic investigations uncovered that these merits originate from the escape of AgNCs from lysosomal degradation within macrophages. In addition, the AgNCs would prime the M1-like polarization of macrophages (at least in part) through the toll-like receptor 4 signaling pathway. The engineered macrophages laden with AgNCs could be employed for lung metastasis breast cancer treatment, showing the effective targeting propensity to metastatic tumors, remarkable regulation of tumor immune microenvironment and inhibition of tumor growth. Collectively, AgNC-trained macrophages appear to be a promising strategy for tumor immune-microenvironment regulation, which might be generalized to a wider spectrum of cancer therapeutics.

Biomimetic doxorubicin/ginsenoside co-loading nanosystem for chemoimmunotherapy of acute myeloid leukemia

BACKGROUND

Acute myeloid leukemia (AML) showed limited clinical therapeutic efficiency with chemotherapy for its multi-distributed lesions and hard-to-kill leukemia cells deep in the bone marrow.

RESULTS

Here, a biomimetic nanosystem (DR@PLip) based on platelet membrane (PM) coating and doxorubicin (DOX)/ginsenoside (Rg3) co-loading was developed to potentiate the local-to-systemic chemoimmunotherapy for AML. The PM was designed for long-term circulation and better leukemia cells targeting. The participation of Rg3 was proved to enhance the tumor sensitivity to DOX, thus initiating the anti-tumor immune activation and effectively combating the leukemia cells hiding in the bone marrow.

CONCLUSIONS

In conclusion, the strategy that combining immediate chemotherapy with long-term immunotherapy achieved improved therapeutic efficiency and prolonged survival, which provided a new perspective for the clinical treatment of AML.

Recent advances of nanodrug delivery system in the treatment of hematologic malignancies

Although the survival rate of hematological malignancies (HM) has increased in recent years, the unnecessary adverse effect to the body is usually generated by the traditional chemotherapy for HM due to the lack of specificity to tumor tissue. Nanodrug delivery systems have exhibited unique advantages in targetability, stability and reducing toxicity, attracting wide concern, which is expected to be the prevalent alternative for the treatment of HM. In this review, we systemically introduced the current therapeutic strategies and the categories of HM. Subsequently, five key factors including circulation, targeting, penetration, internalization and release involving in tailoring nanoparticles were demonstrated, followed by the introduction of the development of nanodrug delivery-traditional synthetic nanomaterilas, biomimetic cell membrane coating nanomaterials, cell-based nanomaterials as well as immunotherapy combined with nanodrug. Afterwards, the recent advances of nanodrug delivery system for the treatment of HM were introduced. Moreover, the challenge and prospect of nanodrug delivery system in treating HM were discussed. The promising drug delivery system will provide new therapeutic avenues for the treatment of HM.