Coronavirus cell in microscopic view. Virus Vaccine Development

SNAP Vaccine Platform

The SNAP (Spontaneous Nanoliposome Antigen Particleization) platform technology is a unique liposome-based system that functions as a potent vaccine adjuvant designed to address functional and practical limitations facing vaccine development.

Recombinant proteins and peptides represent a safe and simple method of vaccine production with the added benefits of defined antigenicity, rapid manufacturing and scale up. However, recombinant proteins often fail to produce a robust immune response, leading to a lack of protection against the disease of interest.  In order to generate a viable immune response, antigens are often coupled to immunogenic carriers,  nanoparticles, or engineered into virus-like particles, a labor-intensive process with significant detriments for vaccine development and manufacturing. The SNAP platform seeks to address these limitations by providing a novel nanoparticle platform that has the functional simplicity of conventional vaccine adjuvants.


The SNAP approach involves simple incubation of His-tagged antigens with SNAP-liposomes (Figure 1A), leading to the insertion of the His-tagged antigen into the bilayer and coordination with cobalt chelated in the porphyrin lipid, forming a His-tag membrane anchor (Figure 1B).

Figure 1A: Simple aqueous incubation results in binding of his-tagged antigens to SNAP liposomes.
Figure 1B: Model of his-tag peptide binding to a bilayer leaflet in SNAP liposomes.

SNAP liposomes before (left) and after incubation (right) resulting in binding of antigen

Platform Advantages


The binding of His-tagged proteins to SNAP-liposomes occurs through simple aqueous mixing.


Antigens can be mixed with SNAP just prior to vaccination, making the SNAP technology platform a multi-use stockpile strategy against emerging diseases, bioterrorism, or pandemics.


Unlike typical vaccine adjuvants, the resulting antibody responses are orders of magnitude higher due to the stable, high-density antigen presentation to the immune system


SNAP-liposomes produce high antibody titers with relatively low antigen dosing, enabling antigen sparing, and the amount of MPLA used is 1000 times lower than is typical, reducing the chance of MPLA associated adverse effects.

SNAP liposomes produce a potent (top) and
durable (bottom) immune response