Intratumoral adoptive transfer of inflammatory macrophages engineered by co-activating TLR and STING signaling pathways exhibits robust antitumor activity.

Despite the success of chimeric antigen receptor (CAR) T cells in hematologic malignancies, adoptive cell therapy (ACT) has not been effective in treating solid tumors. Here, we developed an inflammatory macrophage-based ACT to effectively treat solid tumors. We engineered inflammatory macrophages to enhance their antitumor activities, including proinflammatory cytokine secretion and co-stimulatory molecule expression by co-activating toll-like receptor and stimulator of interferon genes signaling pathways. Engineered macrophages maintain an inflammatory phenotype after their adoptive transfer into the anti-inflammatory tumor microenvironment (TME), whereas conventional inflammatory macrophages prepared using interferon-γ treatment are repolarized to an anti-inflammatory phenotype. In a mouse melanoma model, intratumoral adoptive transfer of engineered macrophages showed robust tumor growth inhibition by increasing CD8+ T cells in the TME and tumor antigen-specific CD8+ T cells in the blood. This study demonstrated that engineered inflammatory macrophages have potential as an effective ACT for treating solid tumors.

Porous Silicon-Based Nanomedicine for Simultaneous Management of Joint Inflammation and Bone Erosion in Rheumatoid Arthritis.

The lack of drugs that target both disease progression and tissue preservation makes it difficult to effectively manage rheumatoid arthritis (RA). Here, we report a porous silicon-based nanomedicine that efficiently delivers an antirheumatic drug to inflamed synovium while degrading into bone-remodeling products. Methotrexate (MTX) is loaded into the porous silicon nanoparticles using a calcium silicate based condenser chemistry. The calcium silicate-porous silicon nanoparticle constructs (pCaSiNPs) degrade and release the drug preferentially in an inflammatory environment. The biodegradation products of the pCaSiNP drug carrier are orthosilicic acid and calcium ions, which exhibit immunomodulatory and antiresorptive effects. In a mouse model of collagen-induced arthritis, systemically administered MTX-loaded pCaSiNPs accumulate in the inflamed joints and ameliorate the progression of RA at both early and established stages of the disease. The disease state readouts show that the combination is more effective than the monotherapies.

Coimmunomodulation of tumor and tumor-draining lymph nodes during in situ vaccination promotes antitumor immunity.

In situ vaccination has demonstrated the feasibility of priming local immunity for systemic antitumor responses. Although direct intratumoral (IT) delivery of adjuvant is the mainstay, tumor-draining lymph nodes (TDLNs) also play essential roles in antitumor immunity. We report that directing an adjuvant to both tumors and TDLNs during in situ vaccination can induce robust antitumor responses. Conventional IT dosing leads to tumor-limited delivery of agents; however, delivery to both tumors and TDLNs can be ensured through a micellar formation. The peritumoral delivery of micellar MEDI9197 (mcMEDI), a toll-like receptor 7/8 agonist, induced significantly stronger innate and adaptive immune responses than those on conventional dosing. Optimal dosing was crucial because excessive or insufficient accumulation of the adjuvant in the TDLNs compromised therapeutic efficacy. The combination of local mcMEDI therapy significantly improved the efficacy of systemic anti-programmed death receptor 1 therapy. These data suggest that rerouting adjuvants to tumors and TDLNs can augment the therapeutic efficacy of in situ vaccination.

Dual size-exclusion chromatography for efficient isolation of extracellular vesicles from bone marrow derived human plasma.

Isolation of pure extracellular vesicles (EVs), especially from blood, has been a major challenge in the field of EV research. The presence of lipoproteins and soluble proteins often hinders the isolation of high purity EVs upon utilization of conventional separation methods. To circumvent such problems, we designed a single-step dual size-exclusion chromatography (dSEC) column for effective isolation of highly pure EVs from bone marrow derived human plasma. With an aim to select appropriate column design parameters, we analyzed the physiochemical properties of the major substances in bone marrow derived plasma, which include EVs, lipoproteins, and soluble proteins. Based on these findings, we devised a novel dSEC column with two different types of porous beads sequentially stacked each other for efficient separation of EVs from other contaminants. The newly developed dSEC columns exhibited better performance in isolating highly pure EVs from AML plasma in comparison to conventional isolation methods.

A mutant KRAS-induced factor REG4 promotes cancer stem cell properties via Wnt/ß-catenin signaling.

Mutant KRAS provides a driving force for enhancement of cancer stem cells (CSCs) characteristics contributing transformation of colorectal cancer (CRC) cells harboring adenomatous polyposis coli (APC) mutations. Here, we identified the factors mediating the promotion of CSCs properties induced by KRAS mutation through microarray analyses of genes specifically induced in CRC spheroids harboring both KRAS and APC mutations. Among them, REG4 was identified as a key factor since CRISPR/Cas9-mediated knockout of REG4 most significantly affected the stem cell characteristics in which CSCs markers were effectively suppressed. We show that REG4 mediates promotion of CSCs properties via Wnt/ß-catenin signaling in various in vitro studies including tumor organoid systems. Furthermore, expression patterns of CSCs markers and REG4 correlated in intestinal tumors from Apcmin/+ /KrasG12D LA2 mice and in CRC patient tissues harboring both KRAS and APC mutations. The role of REG4 in the tumor-initiating capacity accompanied by enhancement of CSCs characteristics was also revealed by NSG mice xenograft system. Collectively, our study highlights the importance of REG4 in promoting CSCs properties induced by KRAS mutation, and provides a new therapeutic strategy for CRC harboring both APC and KRAS mutations.