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Glioblastoma (GBM) is an aggressive primary brain cancer; with a 5-year survival of ~5%. Challenges that hamper GBM therapeutic efficacy include: (i) tumor heterogeneity, (ii) treatment resistance, (iii) immunosuppressive tumor microenvironment (TME) and (iv) the blood-brain barrier (BBB). The C-X-C Motif Chemokine Ligand-12/ C-X-C Motif Chemokine Receptor-4 (CXCL12/CXCR4) signaling pathway is activated in GBM and is associated with tumor progression. Although the CXCR4 antagonist (AMD3100) has been proposed as an attractive anti-GBM therapeutic target, it’s poor pharmacokinetic properties, and unfavorable bioavailability have hampered its clinical implementation. Thus, we developed synthetic protein nanoparticles (SPNPs) coated with the transcytotic peptide iRGD (AMD3100-SPNPs) to target the CXCL2/CXCR4 pathway in GBM via systemic delivery. We showed that AMD3100-SPNPs block CXCL12/CXCR4 signaling in three mouse and human GBM cell cultures in vitro and in a GBM mouse model in vivo. This results in (i) inhibition of GBM proliferation, (ii) reduced infiltration of CXCR4(+) monocytic myeloid derived suppressor cells (M-MDSCs) into the TME, (iii) restoration of BBB integrity, and (iv) induction of immunogenic cell death (ICD), sensitizing the tumor to radiotherapy, and leading to anti-GBM immunity. Additionally, we showed that combining AMD3100-SPNPs with radiation led to long term survival; with ~60% of GBM tumor bearing mice remaining tumor free, after rechallenging with a second GBM in the contralateral hemisphere. This was due to a sustained anti-GBM immunological memory response that prevented tumor recurrence without additional treatment. In view of the potent ICD induction and reprogrammed tumor microenvironment, this SPNP-mediated strategy has a significant clinical translation applicability.

Glioblastoma (GBM), the most aggressive form of brain cancer, has witnessed very little clinical progress over the last decades, in part, due to the absence of effective drug delivery strategies. Intravenous injection is the least invasive drug delivery route to the brain, but has been severely limited by the blood-brain barrier (BBB). Inspired by the capacity of natural proteins and viral particulates to cross the BBB, we engineered a synthetic protein nanoparticle (SPNP) based on polymerized human serum albumin (HSA) equipped with the cell-penetrating peptide iRGD. SPNPs containing siRNA against Signal Transducer and Activation of Transcription 3 factor (STAT3i) result in in vitro and in vivo downregulation of STAT3, a central hub associated with GBM progression. When combined with the standard of care, ionized radiation, STAT3i SPNPs result in tumor regression and long-term survival in 87.5% of GBM-bearing mice and prime the immune system to develop anti-GBM immunological memory., The lack of effective drug delivery strategies has impaired the therapeutic progress in the treatment of glioblastoma (GBM). Here, the authors engineer synthetic protein nanoparticle based on polymerized human serum albumin equipped with the cell-penetrating peptide iRGD to deliver siRNA against STAT3 and report improved survival in a mouse model of GBM.

This study shows that the supramolecular arrangement of proteins in nanoparticle structures predicts nanoparticle accumulation in neutrophils in acute lung inflammation (ALI). We observed homing to inflamed lungs for a variety of nanoparticles with agglutinated protein (NAPs), defined by arrangement of protein in or on the nanoparticles via hydrophobic interactions, crosslinking and electrostatic interactions. Nanoparticles with symmetric protein arrangement (for example, viral capsids) had no selectivity for inflamed lungs. Flow cytometry and immunohistochemistry showed NAPs have tropism for pulmonary neutrophils. Protein-conjugated liposomes were engineered to recapitulate NAP tropism for pulmonary neutrophils. NAP uptake in neutrophils was shown to depend on complement opsonization. We demonstrate diagnostic imaging of ALI with NAPs; show NAP tropism for inflamed human donor lungs; and show that NAPs can remediate pulmonary oedema in ALI. This work demonstrates that structure-dependent tropism for neutrophils drives NAPs to inflamed lungs and shows NAPs can detect and treat ALI.

Glioblastoma multiforme (GBM) is an aggressive primary brain tumor, with poor prognosis. Major obstacles hampering effective therapeutic response in GBM are tumor heterogeneity, high infiltration of immunosuppressive myeloid cells, and the presence of the blood-brain barrier. The C-X-C Motif Chemokine Ligand 12/ C-X-C Motif Chemokine Receptor 4 (CXCL12/ CXCR4) signaling pathway is implicated in GBM invasion and cell cycle progression. While the CXCR4 antagonists (AMD3100) has a potential anti-GBM effects, its poor pharmacokinetic and systemic toxicity had precluded its clinical application. Moreover, the role of CXCL12/ CXCR4 signaling pathway in anti-GBM immunity, particularly in GBM-mediated immunosuppression has not been elucidated. Here, we developed a synthetic protein nanoparticle (SPNPs) coated with the cell-penetrating peptide iRGD (AMD3100 SPNPs) to target the CXCR4/CXCL12 signaling axis in GBM. We showed that AMD3100 SPNPs effectively blocked CXCR4 signaling in mouse and human GBM cells in vitro as well as in GBM model in vivo. This results in inhibition of GBM proliferation and induction of immunogenic tumor cell death (ICD) leading to inhibition of GBM progression. Our data also demonstrate that blocking CXCR4 sensitizes GBM cells to radiation, eliciting enhanced release of ICD ligands. Combining AMD3100 SPNPs with radiotherapy inhibited GBM progression and led to long-term survival; with 60% of mice remaining tumor-free. This was accompanied by an anti-GBM immune response and sustained immunological memory that prevented tumor recurrence without further treatment. Finally, we showed that systemic delivery of AMD3100 SPNPs decreased the infiltration of CXCR4+ monocytic myeloid-derived suppressor cells to the tumor microenvironment. With the potent ICD induction and reprogrammed immune microenvironment, this strategy has significant potential for future clinical translation.Graphical abstractImmunological mechanism targeting Glioblastoma (GBM) upon blocking CXCR4 signaling pathway with AMD3100-conjugated nanoparticles (SPNPs).(1) Radiotherapy induces glioma cell death, followed by Damage-associated molecular patterns (DAMPs) release. Dendritic cells (DC) are activated by DAMPs and migrate to the regional lymph node where they prime cytotoxic T lymphocyte immune response. Tumor-specific cytotoxic T cells infiltrate the tumor and attack glioma cells. (2) Glioma cells express CXCR4, as well its ligand CXCL12. CXCL12 induces glioma cell proliferation and, (3) as well as mobilization in the bone marrow of CXCR4 expressing myeloid MDSC, which will infiltrate the tumor, and inhibit tumor-specific cytotoxic T cells activity. GEMM of glioma when treated systemically with SPNPs AMD3100 SPNPs plus radiation, nanoparticles block the interaction between CXCR4 and CXCL12, thus (4) inhibiting glioma cell proliferation and (5) reducing mobilization in the bone marrow of CXCR4 expressing myeloid MDSC, (6) generating a reduced MDSC tumor infiltration, as well as releasing MDSC inhibition over tumor specific cytotoxic T cell response.

Patterned fiber formation The ability of liquid crystalline materials to order spontaneously has driven many innovations, from display technologies to extremely tough polymer fibers. Cheng et al. exploited this preponderance toward long-range ordering to direct the growth of nonliquid crystalline polymers into sheets of highly ordered fibers. Small changes to the processing conditions could be used to tweak the arrangement of the liquid crystals to generate a wide range of polymer mats or sheets for potential use in sensing or filtration applications. Science , this issue p. 804

Glioblastoma is an aggressive brain tumor with poor prognosis. The brain is protected by the blood–brain barrier, which precludes transport of chemotherapeutics. We developed nanoparticles that achieve delivery of small-interfering RNA against Stat3 after systemic administration. Nanoparticles combined with radiation inhibited tumor progression and elicited anti-glioblastoma immunity in mice.

Protein nanoparticles are a promising approach for nanotherapeutics, as proteins combine versatile chemical and biological function with controlled biodegradability. In this work, the development of an adaptable synthesis method is presented for synthetic protein nanoparticles (SPNPs) based on reactive electrojetting. In contrast to past work with electrohydrodynamic cojetting using inert polymers, the jetting solutions are comprised of proteins and chemically activated macromers, designed to react with each other during the processing step, to form insoluble nanogel particles. SPNPs made from a variety of different proteins, such as transferrin, insulin, or hemoglobin, are stable and uniform under physiological conditions and maintain monodisperse sizes of around 200 nm. SPNPs comprised of transferrin and a disulfide containing macromer are stimuli-responsive, and serve as markers of oxidative stress within HeLa cells. Beyond isotropic SPNPs, bicompartmental nanoparticles containing human serum albumin and transferrin in two distinct hemispheres are prepared via reactive electrojetting. This novel platform provides access to a novel class of versatile protein particles with nanoscale architectures that i) can be made from a variety of proteins and macromers, ii) have tunable biological responses, and iii) can be multicompartmental, a prerequisite for controlled release of multiple drugs.

Acute lung inflammation has severe morbidity, as seen in COVID-19 patients. Lung inflammation is accompanied or led by massive accumulation of neutrophils in pulmonary capillaries (“margination”). We sought to identify nanostructural properties that predispose nanoparticles to accumulate in pulmonary marginated neutrophils, and therefore to target severely inflamed lungs. We designed a library of nanoparticles and conducted an in vivo screen of biodistributions in naive mice and mice treated with lipopolysaccharides. We found that supramolecular organization of protein in nanoparticles predicts uptake in inflamed lungs. Specifically, nanoparticles with agglutinated protein (NAPs) efficiently home to pulmonary neutrophils, while protein nanoparticles with symmetric structure (e.g. viral capsids) are ignored by pulmonary neutrophils. We validated this finding by engineering protein-conjugated liposomes that recapitulate NAP targeting to neutrophils in inflamed lungs. We show that NAPs can diagnose acute lung injury in SPECT imaging and that NAP-like liposomes can mitigate neutrophil extravasation and pulmonary edema arising in lung inflammation. Finally, we demonstrate that ischemic ex vivo human lungs selectively take up NAPs, illustrating translational potential. This work demonstrates that structure-dependent interactions with neutrophils can dramatically alter the biodistribution of nanoparticles, and NAPs have significant potential in detecting and treating respiratory conditions arising from injury or infections.

Delivery of multiple therapeutics has become a preferred method of treating cancer, albeit differences in the biodistribution and pharmacokinetic profiles of individual drugs pose challenges in effectively delivering synergistic drug combinations to and at the tumor site. Here, bicompartmental Janus nanoparticles comprised of domains are reported with distinct bulk properties that allow for independent drug loading and release. Programmable drug release can be triggered by a change in the pH value and depends upon the bulk properties of the polymers used in the respective compartments, rather than the molecular structures of the active agents. Bicompartmental nanoparticles delivering a synergistic combination of lapatinib and paclitaxel result in increased activity against HER2+ breast cancer cells. Surprisingly, the dual drug loaded particles also show significant efficacy toward triple negative breast cancer, even though this cancer model is unresponsive to lapatinib alone. The broad versatility of the nanoparticle platform allows for rapid exploration of a wide range of drug combinations where both their relative drug ratios and temporal release profiles can be optimized.

Clinical translation of nanoparticle-based drug delivery systems is hindered by an array of challenges including poor circulation time and limited targeting. Novel approaches including designing multifunctional particles, cell-mediated delivery systems, and fabrications of protein-based nanoparticles have gained attention to provide new perspectives to current drug delivery obstacles in the interdisciplinary field of nanomedicine. Collectively, these nanoparticle devices are currently being investigated for applications spanning from drug delivery and cancer therapy to medical imaging and immunotherapy. Here, we review the current state of the field, highlight opportunities, identify challenges, and present the future directions of the next generation of multifunctional nanoparticle drug delivery platforms. This article is categorized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Nanotechnology Approaches to Biology > Nanoscale Systems in Biology.

Drug delivery by nanocarriers (NCs) has long been stymied by dominant liver uptake and limited target organ deposition, even when NCs are targeted using affinity moieties. Here we report a universal solution: red blood cell (RBC)-hitchhiking (RH), in which NCs adsorbed onto the RBCs transfer from RBCs to the first organ downstream of the intravascular injection. RH improves delivery for a wide range of NCs and even viral vectors. For example, RH injected intravenously increases liposome uptake in the first downstream organ, lungs, by ~40-fold compared with free NCs. Intra-carotid artery injection of RH NCs delivers >10% of the injected NC dose to the brain, ~10× higher than that achieved with affinity moieties. Further, RH works in mice, pigs, and ex vivo human lungs without causing RBC or end-organ toxicities. Thus, RH is a clinically translatable platform technology poised to augment drug delivery in acute lung disease, stroke, and several other diseases., Unwanted uptake in the liver and limited accumulation in target organs is a major obstacle to targeted drug delivery. Here, the authors report on the hitchhiking of nanocarriers on red blood cells and the targeted upstream delivery to different target organs in mice, pigs and ex vivo human lungs.

Electrohydrodynamic cojetting can result in fibers (electrospinning) and particles (electrospraying) with complex, bicompartmental architectures. An important consideration for application of bicompartmental particles and fibers is the limited throughput derived from the use of parallel capillaries, which require laminar flow to form a multifluidic interface. Here, a novel synthesis approach that takes advantage of an extended bicompartmental fluid interface formed at the sharp edge of a 2D plate is reported. Upon application of an electrical potential to the plate, several electrified fluid jets form spontaneously. Depending on the processing conditions, either bicompartmental particles or fibers with well-defined architectures are prepared. Importantly, this needleless process yields production rates that are more than 30 times higher than those of conventional needle-based techniques. Fiber properties, such as morphology or size, are independent of the flow rate, indicating that this process is physically self-regulating by adjusting the number of jets ejecting from the extended fluid interface. The needleless preparation of bicompartmental particles and fibers is an important technological breakthrough that can enable further advances ranging from drug delivery and tissue engineering to industrial applications.