Liposome Encapsulated siRNA

Due to its specificity and gene silencing function, RNA interference (RNAi) is expected to become an essential approach for the treatment of various infectious, hematological malignancies, cardiovascular and neurodegenerative diseases. Small interfering RNA (siRNA) is a key player in this technology as it can specifically silence the expression of target genes by triggering mRNA degradation. However, efficient delivery of siRNA to target cells remains a major challenge in the development of RNAi-based therapies. Liposome encapsulation has emerged as a promising strategy to overcome this challenge as it can improve siRNA stability and delivery to target cells. BOC Sciences' siRNA liposome encapsulation services provide researchers and pharmaceutical companies with comprehensive solutions for the design, formulation and evaluation of liposome-encapsulated siRNA nanoparticles for a wide range of research and therapeutic applications. In addition, we also provide liposome encapsulation services for small molecules, mRNA, DNA, oligonucleotides, peptides, and proteins.

Fig. 1. The structure of siRNA (European Journal of Pharmacology. 2021, 905: 174178).

Structure of siRNA

siRNA is a 21-23 nucleotide long double-stranded RNA molecule that functions at the post-transcriptional level. This siRNA duplex occurs when long dsRNA is cleaved by Dicer, a member of the RNAse III family. The double strand consists of a passenger strand (sense strand) and a guide strand (antisense strand). siRNA is incorporated into the RNA-induced silencing complex (RISC), where it interacts with Argouate 2 components, leading to duplex unwinding and degradation of the passenger strand (sense strand). A guide strand complementary to the target mRNA guides the RISC complex to the mRNA. In order for the above to occur and result in efficient gene silencing, siRNA should be loaded onto the RISC correctly.

Fig. 2. Selectivity and efficacy challenges of siRNA therapeutics (European Journal of Pharmacology. 2021, 905: 174178).

Notably, the length of siRNA is a key factor in determining the outcome, as siRNAs longer than 30 nucleotides lead to interferon induction and immune responses through activation of Toll-like receptors (TLRs), which results in overall gene Silencing and eventual cell death. The introduction of siRNA may also lead to off-target effects by interfering with the expression of other mRNAs that have partial homology to the target mRNA. Therefore, it is necessary to determine the lowest concentration at which a specific siRNA can induce effective gene silencing.

Mechanism of Action of siRNA

siRNA is a negatively charged macromolecule that is easily degraded by serum endonucleases and has poor cell membrane permeability. Therefore, different types of delivery systems have been developed to protect siRNA from degradation and enhance cellular uptake. These delivery systems include nanocarriers, aptamers, peptides, sugars/amino sugars, proteins, and antibodies. Currently, the mechanism of action of siRNA:

1) siRNA enters cells through appropriate nanocarriers;

2) siRNA binds to ribonucleoprotein (called RNA-induced silencing complex (RISC)) in the cytoplasm;

3) The guide strand of siRNA is maintained by the Argonaute protein in (RISC), and the passenger strand is degraded;

4) Activated RISC recognizes the complementary mRNA of the target gene and induces mRNA degradation.

What is Liposome-Encapsulated siRNA?

Liposome-encapsulated siRNA refers to a process by which siRNA can be incorporated into liposomes to improve its stability and delivery to target cells. siRNA molecules are encapsulated within the aqueous core of liposomes, which protects them from enzymatic degradation and facilitates their uptake by cells. This technology has been extensively studied and applied to develop siRNA-based therapies for the treatment of a variety of diseases, including cancer, viral infections, and genetic disorders. The liposome encapsulation process of siRNA usually involves the following steps:

Step 1: siRNA and lipids are mixed in aqueous solution to form a complex.

Step 2: The complex undergoes a process called lipid hydration, in which the lipids reassemble into a bilayer structure, encapsulating the siRNA in the process.

Step 3: The resulting liposome-encapsulated siRNA complex can be purified and used for in vitro or in vivo applications.

Advantages of Liposome-Encapsulated siRNA

• Liposome encapsulation improves the stability of siRNA molecules.
• Liposome encapsulation protects siRNA from nuclease degradation in the extracellular environment.
• Liposome encapsulation enhances cellular uptake of siRNA.
• Liposome encapsulation enhances specificity of siRNA delivery and minimizes off-target effects.
• Liposome-encapsulated siRNA can be designed to target specific cell types or tissues.
• Liposome encapsulation can enhance the specificity of siRNA delivery and minimize off-target effects.

Our Liposome-Encapsulated siRNA Services

Liposome-encapsulated siRNA services from BOC Sciences leverage our expertise in liposome formulation and siRNA delivery to provide comprehensive solutions for researchers and pharmaceutical companies seeking to develop RNAi-based therapeutics. The service includes the design and synthesis of custom siRNA molecules, formulation of liposome-encapsulated siRNA nanoparticles, and in vitro and in vivo testing to evaluate the efficacy and safety of the delivery system.

Custom siRNA Design and Synthesis

One of the key components of liposome-encapsulated siRNA services is the design and synthesis of custom siRNA molecules tailored to specific gene targets of interest. BOC Sciences' team of experienced scientists can design and synthesize siRNA molecules with high specificity and potency, ensuring effective gene silencing while minimizing off-target effects. Our state-of-the-art facilities and expertise in nucleic acid chemistry enable the production of high-quality siRNA molecules suitable for encapsulation in liposomes.

Liposome Formulation and Optimization

Once custom siRNA molecules are synthesized, they are encapsulated in liposomes to form nanoparticles suitable for targeted delivery to the desired cells and tissues. BOC Sciences' team of formulation experts utilizes multiple lipid compositions and encapsulation methods to optimize the stability, biocompatibility and targeting capabilities of liposome-encapsulated siRNA nanoparticles. By carefully controlling nanoparticle size, surface charge, and lipid composition, we can tailor delivery systems to meet the specific requirements of each research or therapeutic application.

Analysis and Characterization Services

After formulation of the liposome-encapsulated siRNA nanoparticles, BOC Sciences conducted rigorous in vitro and in vivo testing to evaluate the efficacy and safety of the delivery system. In vitro studies involve assessment of cellular uptake, intracellular release, and gene silencing activity of nanoparticles in relevant cell lines or primary cells. On the other hand, in vivo studies involve the administration of nanoparticles to animal models to evaluate their biodistribution, pharmacokinetics, and therapeutic efficacy in disease models.

Application of Liposome Encapsulation siRNA Technology

BOC Sciences' liposome-encapsulated siRNA services have a wide range of applications in both basic research and therapeutic development. In a research setting, this technology can be used to study the function of specific genes and pathways, enabling the identification of potential drug targets and the development of new treatment strategies. In the pharmaceutical industry, liposome-encapsulated siRNA technology holds great promise for the development of RNAi-based therapies to treat a variety of diseases, including cancer, infectious diseases, and genetic disorders.

Fig. 3. siRNA therapies and targeted tissues are currently being studied (European Journal of Pharmacology. 2021, 905: 174178).

Cancer Treatment

One of the most promising applications of liposome-encapsulated siRNA technology is the development of RNAi-based cancer therapies. By targeting the expression of oncogenes, or genes involved in tumor progression, researchers can potentially inhibit the growth and spread of cancer cells. BOC Sciences' liposome-encapsulated siRNA services can be used to design and optimize siRNA molecules targeting specific genes associated with cancer and to formulate liposome-encapsulated nanoparticles for targeted delivery to tumor cells. This approach has huge potential for developing more effective and less toxic cancer treatments.

Infectious Disease Treatment

Another important application of liposome-encapsulated siRNA technology is the development of RNAi-based therapeutics for infectious diseases, including viral and bacterial infections. By targeting essential genes in pathogens, researchers have the potential to inhibit their replication and survival, providing a new approach to antiviral and antibacterial treatments. BOC Sciences' liposome-encapsulated siRNA services can be used to design and optimize siRNA molecules targeting specific viral or bacterial genes and formulate liposome-encapsulated nanoparticles for targeted delivery to infected cells or tissues. This approach holds great promise for the development of more effective and specific treatments for infectious diseases.

Genetic Disease Treatment

Liposome-encapsulated siRNA technology also has great potential in developing RNAi-based therapies for genetic diseases, including hereditary and rare genetic diseases. By targeting the expression of disease-causing genes, researchers have the potential to reduce the symptoms and progression of these diseases. BOC Sciences' liposome-encapsulated siRNA services can be used to design and optimize siRNA molecules targeting specific disease-causing genes and formulate liposome-encapsulated nanoparticles for targeted delivery to affected tissues. This approach holds great promise for developing more targeted and personalized treatments for genetic diseases.

Case Study

BOC Sciences' liposome-encapsulated siRNA services solved a significant challenge for our client, a leading pharmaceutical company. Customers faced challenges in delivering siRNA to specific target cells in the body, which is critical for their gene therapy research. Working with BOC Sciences, they overcame these obstacles and achieved significant success.

The BOC Sciences team leveraged their expertise in liposome formulation and encapsulation to create the appropriate particle size and charge for the siRNA being studied by the customer. Then we also optimized the liposome encapsulation formula according to customer needs to achieve efficient delivery of siRNA. This enables customers to deliver targeted siRNA to desired cells, resulting in significant gene silencing and therapeutic effects. Thanks to BOC Sciences' liposome-encapsulated siRNA services, the customer was able to overcome a major hurdle in this research and move one step closer to developing a potential treatment for a rare genetic disease.

Reference

1. Alshaer, W. et al. siRNA: Mechanism of action, challenges, and therapeutic approaches. European Journal of Pharmacology. 2021, 905: 174178.