Lipids for RNA Cancer-Vaccine Research

DA lipid is a dopamine-derived ionizable lipid incorporating a catechol antioxidant headgroup, one tertiary amine and two ester-linked branched hydrophobic tails. In the cited study, DA lipid and DA lipid nanoparticles scavenged reactive oxygen species more effectively than their oxidized ODA counterparts. DA LNPs supported higher mRNA-derived protein expression than ODA LNPs in DC2.4 cells and after intramuscular administration in mice, with expression comparable to ALC-0315 LNPs. OVA mRNA-loaded DA LNPs improved antigen presentation and suppressed tumor growth in a prophylactic B16-OVA melanoma model relative to ODA LNPs. These results support research into antioxidant mRNA delivery and preventive cancer vaccination.

​TOT-5​​, a tri-oleoyl-Tris ionizable lipid (pKa 6.2), enables splenic B cell-targeted mRNA delivery via 15% DSPC-incorporated LNPs. Its charge-neutral, hydrophobic surface minimizes hepatic ApoE uptake and enhances complement C3 adsorption, facilitating CD21/35-mediated uptake by marginal zone B cells. In vivo, intravenous 15%DSPC-LNPs showed 8-fold higher spleen-to-liver luciferase expression vs 3%DSPC, with anti-CD21/35 blocking 60% B cell uptake. Intramuscular administration induced robust OVA-specific IgG (10^5 titer) and CTL responses (3.5% tetramer+ CD8+ T cells) while reducing hepatotoxicity (ALT/AST levels ≤40 U/L vs SM-102-LNPs' 80-120 U/L). Cryo-ET confirmed stable lamellar structures (80-100 nm, ζ-potential -2 mV). This formulation achieves safe, ligand-free splenic targeting for mRNA vaccines.

AMG514 is a novel ionizable lipid designed for formulating spleen-targeting lipid nanoparticles (LNPs) to deliver immune‑remodeling mRNAs (IR‑mRNAs). Its key advantage lies in the formation of a unique “protein corona” enriched with vitronectin, coagulation factors, and specific apolipoproteins (e.g., ApoA‑IV), together with its relatively high apparent pKa (~7.5), which actively redirects LNPs to the spleen instead of the liver. This precise spleen‑targeting property enables efficient transfection of splenic antigen‑presenting cells (APCs). As a vaccine adjuvant, AMG514‑LNPs therefore elicit a more robust activation of adaptive immunity compared to conventional LNPs (e.g., cKK‑E12), generating significantly enhanced antigen‑specific CD8⁺ T‑cell and antibody responses, and inducing durable anti‑tumor immune memory in preclinical models.

D-Lin-MC3-DMA(MC3) is the most potent cationic lipid that has been synthesized for Lipid nanoparticles (LNPs) to deliver the siRNA.

ALC-0315 is an ionisable aminolipid that used for mRNA compaction and aids mRNA cellular delivery. ALC-0315 can be used to form lipid nanoparticle (LNP) delivery vehicles.

CKK-E12 is a ionizable lipid in combination with other lipids make up the lipid nanoparticles which are used to deliver RNA-based therapeutics. cKK-E12 was highly selective toward liver parenchymal cell in vivo.Multitail lipids usually have three or more tails and tend to form more cone-shaped structures due to the increase of tail crosssection, which enhances the endosome escape and mRNA delivery efficiency.CKK-E12 is an ionizable lipid with four lipid tails and diketopiperazine core-based head. It has shown excellent efficiency in delivering CRISPR-Cas9 mRNA and sgRNA.cKK-E12 iLNPs encapsulated mRNA was used to investigate the effect of Toll-like receptor 4 (TLR4) on iLNPsmediated mRNA delivery, and it has been demonstrated that the targeting, safety and efficacy of iLNPs are closely related to disease state. In other words, even though iLNP delivers therapeutic mRNA to a given cell type in one disease state, it is not guaranteed to deliver mRNA to the same cell type in another disease. As same as MC3 and C12-200, CKK-E12 is also used to be a positive control ionizable lipid when exploiting new ionizable lipids.

SM-102 is an ionizable amino lipid that has been used in combination with other lipids in the formation of lipid nanoparticles.Administration of luciferase mRNA in SM-102-containing lipid nanoparticles induces hepatic luciferase expression in mice. Formulations containing SM-102 have been used in the development of lipid nanoparticles for delivery of mRNA-based vaccines.

C12-200 is a well-known cationic lipid used in the formulation of lipid nanoparticles (LNPs) for the delivery of therapeutic nucleic acids, including siRNA, mRNA, and CRISPR components. It is widely recognized for its high in vivo potency at low doses and is often used as a positive control ionizable lipid in research exploring new ionizable lipids.

DMA4-H228 is a novel, biodegradable lipidoid specifically engineered for spleen-targeted mRNA delivery.​​ Its structure combines a dimethylamino (DMA4) headgroup with a unique hyperbranched lipid tail (H228) synthesized via Michael addition, incorporating ester bonds for enhanced biodegradability. This design enables the formation of stable lipid nanoparticles (LNPs) (~170 nm) with high mRNA encapsulation efficiency (>96%). Critically, DMA4-H228 exhibits exceptional intrinsic tropism for the spleen (>98% targeting efficiency after IV administration), requiring no external targeting ligands. It selectively delivers mRNA to splenic antigen-presenting cells (APCs), including dendritic cells, macrophages, and B cells. This triggers potent immune activation: rapid IFNα secretion, upregulation of APC maturation markers (CD86/CD40), and robust antigen-specific immune responses. Demonstrating significant therapeutic potential, DMA4-H228-based mRNA vaccines effectively inhibit tumor growth in melanoma models (e.g., B16F10-OVA). This correlates with increased tumor-infiltrating CD8⁺ T cells, a shift towards pro-inflammatory M1 macrophages, elevated antigen-specific antibodies (IgG), and strong T cell responses (evidenced by IFNγ⁺ spots). Its ability to bypass liver tropism and directly activate splenic APCs makes DMA4-H228 a powerful platform for next-generation mRNA vaccines and cancer immunotherapy.

EB-Lipid is an innovatively engineered ionizable lipid designed to replace conventional PEG-lipid in mRNA vaccine formulations. Its structure comprises three key components: an Evans Blue-derived headgroup with high affinity for albumin, a tetraethylene glycol linker that enhances colloidal stability, and dual oleate tails for anchoring into lipid bilayers. This molecular design enables EB-Lipid to actively recruit endogenous albumin, forming an albumin-rich protein corona on the surface of lipid nanoparticles (LNPs). Following intramuscular administration, these albumin-bound EB-LNPs are preferentially transported through lymphatic vessels rather than entering the bloodstream, thereby avoiding hepatic accumulation and associated hepatotoxicity risks.Experimental data demonstrate that EB-LNPs achieve significantly higher accumulation in lymph nodes, where they are efficiently internalized by dendritic cells via albumin receptor-mediated endocytosis (e.g., gp60). This process enhances antigen presentation and activates robust cellular and humoral immune responses. In both tumor models (B16-OVA and HPV-associated) and infectious disease models (H1N1 and SARS-CoV-2 Omicron), EB-LNP-based mRNA vaccines elicited potent cytotoxic T-cell activation and durable neutralizing antibody production at low doses. Unlike traditional PEG-LNPs, EB-LNPs show minimal liver distribution, reduced immunogenicity, and improved safety profiles after repeated administrations.By leveraging albumin’s natural trafficking pathway, EB-Lipid represents a transformative delivery platform that combines targeted lymph node delivery with enhanced biosafety, positioning it as a promising candidate for next-generation mRNA vaccines and therapeutics.

113-O12B LNP, an LN-targeting LNP delivery system, is developed for a mRNA cancer vaccine.

A2-Iso5-2DC18 is a top-performing lipid for mRNA delivery in bone marrow-derived dendritic cells (BMDCs), BMDMs and HeLa cells.

A18-Iso5-2DC18 that could not only deliver mRNA vaccines robustly but also activate the stimulator of interferon genes (STING) pathway.

A12-Iso5-2DC18 is a novel amine containing lipid can be used for mRNA delivery, activate the stimulator of interferon genes (STING) pathway, and exhibit anti-tumor immunity.

C12-2aN is a crosslinked ionizable lipid developed for mRNA vaccine delivery and dendritic-cell metabolic reprogramming. Its structure combines two piperazine-based ionizable amine cores, a bis-amidine crosslinker, and four hydroxylated C12 hydrophobic tails. When formulated with DOPE, cholesterol, and C14-PEG2000, C12-2aN LNPs enhanced mRNA endosomal escape and activated AMPK–mTORC2-dependent glycolysis, supporting dendritic-cell maturation and antigen presentation. In preclinical mouse studies, C12-2aN LNPs generated robust humoral and cellular immune responses in SARS-CoV-2 RBD and OVA cancer-vaccine models. The formulation also demonstrated reduced liver-associated off-target expression and lower acute inflammatory markers than the tested control formulations. C12-2aN is a preclinical research lipid intended for evaluating metabolically active mRNA vaccine delivery systems.

ST12 is a lipid-conjugated DMXAA prodrug designed for temporally controlled STING activation in mRNA vaccine formulations. Its structure integrates a mouse-specific STING agonist, a biodegradable ester linker, an RNA-interacting tertiary amine domain, and two hydrophobic tails. When incorporated as a partial replacement for SM-102, ST12 preserves early antigen mRNA translation and subsequently releases DMXAA to activate STING. This delayed activation supports localized type I interferon signaling, enhanced antigen-specific CD8-positive T-cell responses, and improved antitumor immunity. In preclinical OVA and HPV tumor models, ST12-based Syn-STING vaccines suppressed tumor growth and prolonged survival. ST12 remains a preclinical research lipid developed specifically around DMXAA-sensitive STING systems.

HCQ-4​​ is a rationally engineered ionizable lipid derived from hydroxychloroquine (HCQ), featuring a ​​ditetradecylamine-derived twin-C14 saturated hydrocarbon tail​​ linked to the HCQ headgroup via a ​​succinic acid spacer​​. Synthesized through a three-step route involving HCQ deprotonation, ditetradecylamine carboxylation, and EDC/DMAP-mediated amidation, this lipid forms the core of optimized lipid nanoparticles (LNPs) at a molar ratio of ​​60:10:40:0.5 (HCQ-4:DOPE:cholesterol:DMG PEG 2000 )​​. The structure enables dual functionality: (1) ​​Spleen-selective mRNA delivery​​ (2.3-fold higher splenic vs. hepatic transfection) via 80-100 nm particle size, near-neutral charge (-3 mV), and low PEG density, facilitating immune cell uptake; (2) ​​Tumor microenvironment modulation​​ through HCQ-mediated repolarization of M2 macrophages to antitumor M1 phenotype (iNOS + cells ↑2.5-fold, CD206 + cells ↓60%). This bifunctional design synergistically enhances mRNA cancer vaccine efficacy, demonstrating superior prophylactic/therapeutic antitumor activity and antimetastatic effects compared to clinical benchmarks like MC-3 LNP.

GL5 is an ionizable guanidine-based lipid nanoparticle (G-LNP) designed for superior mRNA delivery. Its guanidinocarbonyl-pyrrole (GCP) headgroup enables pH-responsive behavior and strong mRNA binding via bidentate hydrogen bonds. The cholesterol-free GL5-3 formulation forms compact, stable nanoparticles (~90-120 nm) that exhibit excellent spleen-targeting capability after intravenous injection.GL5-LNPs efficiently deliver mRNA to antigen-presenting cells (APCs), enhancing antigen presentation and T cell activation. In cancer immunotherapy models, GL5-based mRNA vaccines provided complete tumor protection and induced durable immune memory. The platform also enables mRNA delivery to other organs like the pancreas via different administration routes, demonstrating remarkable versatility and therapeutic potential.

(4S)-KEL12​​ is a novel, biodegradable ionizable lipid developed for advanced mRNA vaccine delivery. It was rationally designed by incorporating both a ketal group in the linker and ester segments in the hydrophobic tails, a dual-degradable strategy aimed at enhancing its safety profile. Through iterative optimization, (4S)-KEL12 was identified as a lead candidate with an optimal pKa value of approximately 6.78, which is crucial for efficient mRNA encapsulation and endosomal release.