Introducing Cytofinity™ LNP, a groundbreaking solution in the non-viral delivery of nucleic acid payloads for in vivo cell and gene therapy. Unlike existing LNP systems, Cytofinity™ LNP has the unique ability to target extrahepatic cells and organs without needing antibody conjugation, revolutionizing the current approaches for targeted delivery.
Cytodigm has successfully developed Cytofinity™ LNPs by replacing PEG-lipid, a key component in traditional LNP formulations, with ganglioside, a natural lipid that contains sialic acid (Sia) ligands. The hydrophilic Sia ligands are located on the surface of the LNPs and bind Siglec receptors on different types of cells, facilitating cell and tissue targeting via receptor-mediated endocytosis.
a. Hematopoietic stem cells (HSCs) in the bone marrow
b. Epithelial, endothelial, and ciliated cells in the lung
c. T cells and NK cells in PBMC and Spleen
Cytofinity™ LNPs target cells through the binding of Siglec receptors on the cell surface
Unlike traditional LNPs, which cannot withstand the high shear forces during nebulization, Cytofinity™ LNPs can be nebulized for efficient delivery of RNA cargo to the lung
mRNA-loaded Cytofinity™ LNPs survived the nebulization process and kept their particle size and encapsulation efficiency (EE) unchanged whereas standard LNPs had increased size and reduced EE
In vivo and ex vivo IVIS images 4 hours after inhalation of
nebulized Cytofinity™ LNPs loaded with Luc-mRNA
Immunohistochemical analysis indicates that the CytofinityTM LNPs loaded with Luc-mRNA
have been delivered to epithelial, endothelial, and ciliated cells in the lung.
Polyethylene glycol (PEG) is widely used to enhance drug delivery because PEG can reduce clearance by the reticuloendothelial system (RES) to prolong the circulation of therapeutic substances and improve their pharmacokinetics. PEG-lipid has been an essential component of LNPs, stabilizing the nanoparticles and reducing their sizes.
However, PEG has recently been discovered to trigger anaphylaxis to the mRNA-based Covid vaccines. Formation of anti-PEG antibodies can lead to accelerated blood clearance (ABC), rendering repeat dosing impossible. Additionally, PEG can induce complement activation-related pseudo-allergies (CARPA).
The efforts to replace PEG-lipid in LNP formulations have been largely unsuccessful. Most PEG-replacing approaches use synthetic analogs, which can cause immunogenicity like PEG.
Certain natural or biocompatible substances proposed to replace the PEG-lipid, such as hyaluronic acid and polysialic acid, must be chemically linked to lipids or LNPs. However, these conjugates might induce an immune response, and the conjugation process can produce harmful byproducts. Additionally, some of these “PEG Substitutes” may be too large and hydrophilic, which could compromise the integrity and stability of the LNPs.
Cytofinity™ is the first LNP system formulated with ganglioside, a non-immunogenic natural lipid, to replace the PEG-lipid in the LNP formulation.
Ganglioside is a natural lipid widely present in the human body. As a result, it is very safe and has low immunogenicity. Cytofinity™ LNP contains a selected ganglioside with a good hydrophobic-hydrophilic balance, ensuring high LNP integrity and stability. Incorporating the ganglioside in Cytofinity LNP avoids the conjugation, further improving the LNP safety.
In the realm of gene therapy, traditional lipid nanoparticles (LNPs) are primarily liver-tropic, meaning they naturally accumulate in the liver. While this characteristic can be advantageous for therapies targeting liver-specific diseases, it poses significant challenges when the therapeutic target lies elsewhere in the body. The unintended accumulation of LNPs in the liver can lead to off-target effects and liver toxicity, compromising patient safety and therapeutic efficacy. As such, “detargeting” the liver is a critical focus in the development of next-generation LNPs. By engineering LNPs to bypass the liver and reach specific target tissues or cells, researchers aim to minimize liver-related side effects and unleash the full potential of gene therapies for a broader range of diseases, thereby improving treatment outcomes and expanding the therapeutic applications of LNP-based delivery systems.
As shown in the figure below, 48 hours after systemically injecting Cytofinity LNP and traditional LNP loaded with a GFP-mRNA, the Cytofinity group exhibited much lower GFP expression in the liver than the traditional LNP group. This indicates that Cytofinity LNPs can detarget the liver and thus reduce LNP-mediated liver toxicity.
Ex vivo IVIS on Liver at 48-hr
