Accelerated Blood Clearance of Antibodies by Nanosized Click Antidotes

Clicking in harmony: exploring the bio-orthogonal overlap in click chemistry

In the quest to scrutinize and modify biological systems, the global research community has continued to explore bio-orthogonal click reactions, a set of reactions exclusively targeting non-native molecules within biological systems. These methodologies have brought about a paradigm shift, demonstrating the feasibility of artificial chemical reactions occurring on cellular surfaces, in the cell cytosol, or within the body - an accomplishment challenging to achieve with the majority of conventional chemical reactions. This review delves into the principles of bio-orthogonal click chemistry, contrasting metal-catalyzed and metal-free reactions of bio-orthogonal nature. It comprehensively explores mechanistic details and applications, highlighting the versatility and potential of this methodology in diverse scientific contexts, from cell labelling to biosensing and polymer synthesis. Researchers globally continue to advance this powerful tool for precise and selective manipulation of biomolecules in complex biological systems.

Microgels as Platforms for Antibody-Mediated Cytokine Scavenging

Therapeutic antibodies are the key treatment option for various cytokine-mediated diseases, such as rheumatoid arthritis, psoriasis, and inflammatory bowel disease. However, systemic injection of these antibodies can cause side effects and suppress the immune system. Moreover, clearance of therapeutic antibodies from the blood is limiting their efficacy. Here, water-swollen microgels are produced with a size of 25 µm using droplet-based microfluidics. The microgels are functionalized with TNFα antibodies to locally scavenge the pro-inflammatory cytokine TNFα. Homogeneous distribution of TNFα-antibodies is shown throughout the microgel network and demonstrates specific antibody-antigen binding using confocal microscopy and FLIM-FRET measurements. Due to the large internal accessibility of the microgel network, its capacity to bind TNFα is extremely high. At a TNFα concentration of 2.5 µg mL-1 , the microgels are able to scavenge 88% of the cytokine. Cell culture experiments reveal the therapeutic potential of these microgels by protecting HT29 colorectal adenocarcinoma cells from TNFα toxicity and resulting in a significant reduction of COX II and IL8 production of the cells. When the microgels are incubated with stimulated human macrophages, to mimic the in vivo situation of inflammatory bowel disease, the microgels scavenge almost all TNFα that is produced by the cells.

Polymer Nanoantidotes

Intoxication is one of the most common causes of accidental death globally. Although some antidotes capable of neutralizing the toxicity of certain xenobiotics have become well established, the current reality is that clinicians primarily rely on nonspecific extracorporeal techniques to remove toxins. Nano-intervention strategies in which nanoantidotes neutralize toxicity in situ via physical interaction, chemical bonding, or biomimetic clearance have begun to show clinical potential. However, most nanoantidotes remain in the proof-of-concept stage, and the difficulty of constructing clinical relevance models and the unclear pharmacokinetics of nanoantidotes hinder their translation to clinic. This Concept reviews the detoxification mechanisms of polymer nanoantidotes and predicts the opportunities and challenges associated with their clinical application.

Nanomedicine embraces cancer radio-immunotherapy: mechanism, design, recent advances, and clinical translation

Cancer radio-immunotherapy, integrating external/internal radiation therapy with immuno-oncology treatments, emerges in the current management of cancer. A growing number of pre-clinical studies and clinical trials have recently validated the synergistic antitumor effect of radio-immunotherapy, far beyond the "abscopal effect", but it suffers from a low response rate and toxicity issues. To this end, nanomedicines with an optimized design have been introduced to improve cancer radio-immunotherapy. Specifically, these nanomedicines are elegantly prepared by incorporating tumor antigens, immuno- or radio-regulators, or biomarker-specific imaging agents into the corresponding optimized nanoformulations. Moreover, they contribute to inducing various biological effects, such as generating in situ vaccination, promoting immunogenic cell death, overcoming radiation resistance, reversing immunosuppression, as well as pre-stratifying patients and assessing therapeutic response or therapy-induced toxicity. Overall, this review aims to provide a comprehensive landscape of nanomedicine-assisted radio-immunotherapy. The underlying working principles and the corresponding design strategies for these nanomedicines are elaborated by following the concept of "from bench to clinic". Their state-of-the-art applications, concerns over their clinical translation, along with perspectives are covered.

Highly aminated iron oxide nanoworms for simultaneous manufacturing and labeling of chimeric antigen receptor T cells

Cell based therapies including chimeric antigen receptor (CAR) T cells are promising for treating leukemias and solid cancers. At the same time, there is interest in enhancing the functionality of these cells via surface decoration with nanoparticles (backpacking). Magnetic nanoparticle cell labeling is of particular interest due to opportunities for magnetic separation, in vivo manipulation, drug delivery and magnetic resonance imaging (MRI). While modification of T cells with magnetic nanoparticles (MNPs) was explored before, we questioned whether MNPs are compatible with CAR-T cells when introduced during the manufacturing process. We chose highly aminated 120 nm crosslinked iron oxide nanoworms (CLIO NWs, ~36,000 amines per NW) that could efficiently label different adherent cell lines and we used CD123 CAR-T cells as the labeling model. The CD123 CAR-T cells were produced in the presence of CLIO NWs, CLIO NWs plus protamine sulfate (PS), or PS only. The transduction efficiency of lentiviral CD123 CAR with only NWs was ~23% lower than NW+PS and PS groups (~33% and 35%, respectively). The cell viability from these three transduction conditions was not reduced within CAR-T cell groups, though lower compared to non-transduced T cells (mock T). Use of CLIO NWs instead of, or together with cationic protamine sulfate for enhancement of lentiviral transduction resulted in comparable levels of CAR expression and viability but decreased the proportion of CD8+ cells and increased the proportion of CD4+ cells. CD123 CAR-T transduced in the presence of CLIO NWs, CLIO NWs plus PS, or PS only, showed similar level of cytotoxicity against leukemic cell lines. Furthermore, fluorescence microscopy imaging demonstrated that CD123 CAR-T cells labeled with CLIO NW formed rosettes with CD123+ leukemic cells as the non-labeled CAR-T cells, indicating that the CAR-T targeting to tumor cells has maintained after CLIO NW labeling. The in vivo trafficking of the NW labeled CAR-T cells showed the accumulation of CAR-T labeled with NWs primarily in the bone marrow and spleen. CAR-T cells can be magnetically labeled during their production while maintaining functionality using the positively charged iron oxide NWs, which enable the in vivo biodistribution and tracking of CAR-T cells.

Bioorthogonal Reactions in Animals

The advent of bioorthogonal chemistry has led to the development of powerful chemical tools that enable increasingly ambitious applications. In particular, these tools have made it possible to achieve what is considered to be the holy grail of many researchers involved in chemical biology: to perform unnatural chemical reactions within living organisms. In this minireview, we present an update of bioorthogonal reactions that have been carried out in animals for various applications. We outline the advances made in the understanding of fundamental biological processes, and the development of innovative imaging and therapeutic strategies using bioorthogonal chemistry.

An Appraisal of Antidotes' Effectiveness: Evidence of the Use of Phyto-Antidotes and Biotechnological Advancements

Poisoning is the greatest source of avoidable death in the world and can result from industrial exhausts, incessant bush burning, drug overdose, accidental toxication or snake envenomation. Since the advent of Albert Calmette’s cobra venom antidote, efforts have been geared towards antidotes development for various poisons to date. While there are resources and facilities to tackle poisoning in urban areas, rural areas and developing countries are challenged with poisoning management due to either the absence of or inadequate facilities and this has paved the way for phyto-antidotes, some of which have been scientifically validated. This review presents the scope of antidotes’ effectiveness in different experimental models and biotechnological advancements in antidote research for future applications. While pockets of evidence of the effectiveness of antidotes exist in vitro and in vivo with ample biotechnological developments, the utilization of analytic assays on existing and newly developed antidotes that have surpassed the proof of concept stage, as well as the inclusion of antidote’s short and long-term risk assessment report, will help in providing the required scientific evidence(s) prior to regulatory authorities’ approval.

pH/redox dual-stimuli-responsive cross-linked polyphosphazene nanoparticles for multimodal imaging-guided chemo-photodynamic therapy

Multifunctional nanodrugs with the integration of precise diagnostic and effective therapeutic functions have shown great promise in improving the efficacy of cancer therapy. We report herein a simple and effective approach to directly assemble an anticancer drug (curcumin), a photodynamic agent (Ce6) and tumor environment-sensitive molecules into cross-linked polyphosphazene and coat on superparamagnetic Fe3O4 nanoclusters to form discrete nanoparticles (termed as FHCPCe NPs). FHCPCe NPs have high physiological stability and good biocompatibility, and can enhance accumulation in tumor tissue via the enhanced permeability and retention effect. Meanwhile, the FHCPCe NPs exhibit an effective performance of dual-modality magnetic resonance imaging (MRI) due to the Fe3O4 cores and fluorescence imaging (FL) in the xenografted HeLa tumor because of the fluorescence of Ce6. Importantly, under the conditions of supernormal glutathione levels and acidic microenvironment in tumor tissue, curcumin and Ce6 can be effectively released by the degradation of FHCPCe NPs. Therefore, excellent anti-tumor effects both in vitro and in vivo have been achieved by synergistic chemotherapy/photodynamic therapy (CT/PDT) using multifunctional NPs. Our study highlights the promise of developing multifunctional nanomaterials for accurate multimodal imaging-guided highly sensitive therapy of cancer.