Nanotechnology-enabled immunoengineering approaches to advance therapeutic applications

Purpose: Immunotherapy has improved outcomes in cancer and infectious disease, but off-target effects, systemic toxicities, and variable efficacy remain limiting. Nanoscale engineering offers ways to manipulate immune cell functions—enhancing immunity against cancers and pathogens, controlling the site of immune response, and promoting tolerance—by tuning nanoparticle size, shape, charge, and surface chemistry.

Hypothesis: No formal experimental hypothesis. Central thesis: nano-immunoengineering—using nanoparticle platforms to deliver immunomodulatory drugs, biologics, nucleic acids, and gene-editing tools—can enhance, control, or regulate immune cell functions; improve delivery and efficacy; reduce systemic toxicity; and enable in situ immune cell programming for cancer, infectious disease, autoimmunity, and tissue regeneration.

Aims: Define the concept of nano-immunoengineering and its scope. - Review nanoparticle platforms for enhancing anti-tumor immunity, including checkpoint blockade, tumor microenvironment reprogramming, cancer vaccines, and adoptive cell transfer. - Discuss nanoparticle-based approaches for infectious disease vaccines, including subunit, viral, and mRNA vaccines. - Review nanotechnology for promoting tolerance in autoimmunity and suppressing chronic inflammation. - Highlight nanomaterials for tissue regeneration and wound healing. - Discuss cutting-edge technologies and future translational perspectives.

Delivery system: Nanoparticle materials: lipids (liposomes, lipid nanoparticles, ionizable lipids, cationic lipids), polymers (PLGA, PBAE, PEI, PLL, chitosan, pDMAEMA, PGA), proteins, inorganic materials (gold, iron oxide, silica, mesoporous silica, upconversion nanoparticles), exosomes/extracellular vesicles. - Payloads: monoclonal antibodies (anti-PD-1, anti-CTLA-4, anti-CD47), nucleic acids (pDNA, mRNA, siRNA, miRNA), CRISPR-Cas9 ribonucleoproteins, cytokines (IL-2, IL-15Sa, IL-21, IL-27), small-molecule drugs (TGF-β inhibitors, STAT3/HIF-1α inhibitors, IMD-0354, axitinib, methotrexate, teriflunomide, methylthioadenosine), antigens (Trp2, OVA, MBP, MOG, anthrax PA, flagellin), adjuvants (CpG, TLR agonists). - Targeting/functionalization: mannose, CD45, CD90, anti-CD8, anti-CD3ε, folate receptor β, ART-1 peptide, PEGylation, cell-membrane coatings, magnetic guidance, light-responsive UCNPs. - Routes: intravenous, intramuscular, subcutaneous, intranasal, oral, topical. - Applications: cancer immunotherapy, cancer vaccines, CAR T/NK/macrophage engineering, infectious disease vaccines, autoimmune disease, chronic inflammation, wound healing, cardiac and skeletal muscle regeneration.

Approach: Review of preclinical and clinical literature; no primary experiments. Preclinical models include B16F10 melanoma, EG7-OVA thymoma, prostate cancer, ovarian cancer, glioma, pulmonary melanoma metastases, multiple sclerosis models (EAE, cuprizone), collagen-induced arthritis, wound healing, myocardial infarction, and skeletal muscle regeneration. In vitro systems include RAW264.7, BMDMs, DCs, T cells, NK cells, macrophages, Jurkat, K-562, and NK-92 cells. Clinical context includes COVID-19 mRNA vaccines (Moderna mRNA-1273, Pfizer-BioNTech BNT162b2) and CAR T-cell therapy.

Key methods: Nanoparticle characterization: size, zeta potential, morphology (TEM), encapsulation efficiency, pKa. - Immune cell function: flow cytometry, cytokine secretion (IFN-γ, TNF-α, IL-6, IL-10), T-cell proliferation, CTL activity, macrophage polarization (M1/M2). - Gene delivery/editing: transfection efficiency, CAR expression, gene knockout, indel rates. - In vivo efficacy: tumor size, survival, metastasis, arthritic score, locomotor activity, myelination, wound healing, infarct healing. - Imaging/tracking: MRI, fluorescence imaging, bioluminescence. - Safety: systemic toxicity, cytokine release syndrome markers, B cell aplasia.

Key results: CL4H6 lipid nanoparticles silenced STAT3 and HIF-1α in tumor-associated macrophages by 37% and 48%, respectively, increased M1 markers, reduced tumor size, and altered cytokine profiles in a B16-F10 model. - PBAE-mannose nanocarriers co-delivering IRF5 and IKK mRNA reprogrammed M2 TAMs to M1, slowed tumor growth, and doubled survival in an ovarian cancer mouse model. - In situ CAR T-cell generation via PBAE mRNA nanocarriers achieved ~75% transfection efficiency in vitro; repeated dosing produced ~10% gene transfer into host T cells in vivo, eradicated tumors, and extended survival by 42 days in a prostate tumor model. - Light-switchable CAR T cells with upconversion nanoplates reduced B cell aplasia and serum IL-6 compared with wild-type CAR T cells, lowering on-target/off-tumor toxicity and cytokine release syndrome. - MTA-loaded solid lipid nanoparticles increased elimination half-life from 28 min to 1.25 h, improved locomotor activity to 71% vs 49%, and increased myelination to 80% vs 57% in a cuprizone-induced demyelination model. - mRNA-1273 LNP uses ionizable lipid SM-102 with pKa 6.75; BNT162b2 uses an ionizable lipid with pKa 6.09; both use N1-methylpseudouridine-modified mRNA. - Anthrax T4 virus-like particle vaccine protected mice, rats, and rabbits against 100% lethal toxin challenge, eliciting humoral and cellular immunity. - TB liposomal subunit vaccine encapsulating Ag85B and ESAT-6 induced high IFN-γ and IL-17A responses in mice.

Interpretation: Nano-immunoengineering provides a powerful, versatile way to control and interrogate immune cell functions. Nanoparticles can enable in situ cell programming, overcome viral vector packaging and safety limitations, improve targeting and controlled release, and reduce cost and preparation time for next-generation immunotherapies. The authors argue this approach can broaden patient access to safer and more effective treatments.

Limitations: Review article; no primary data. - Most discussed platforms remain preclinical; clinical translation is limited. - Solid tumor delivery remains inefficient, with less than 1% of systemically administered nanoparticles reaching target tumors. - Gene transfer efficiency into primary immune cells is still low, especially for pDNA. - Viral vectors remain more efficient for gene transfer but carry immunogenicity, tumorigenicity, and packaging limitations. - Nanoparticle toxicity, off-target effects, long-term safety, manufacturing scale-up, and regulatory pathways require further study. - Autoimmune disease pathology is complex and heterogeneous; tolerance induction strategies need more clinical validation. - Stimuli-responsive systems such as light-activated CAR T cells face tissue penetration and absorption limitations. - The field needs deeper understanding of nanomaterial–immune system interactions and standardized translational benchmarks.