Description:
Subunit vaccines consist of recombinant or synthetic antigens, such as peptides or protein fragments, which are carefully chosen from the mechanistic analysis of the disease progression. These vaccines offer considerable advantages over the traditional vaccines in terms of specificity, safety and cost of production. However, due to rapid degradation of the vaccines by the host organism, they often show low effectiveness rates. In order to enhance the effectiveness of subunit vaccines there is currently a great need for novel adjuvants. Alum is the most widely used vaccine adjuvant, but it fails to elicit cytotoxic responses needed to mount a strong immune response to an antigen. In recent years mesoporous silica particles have been proposed as an alternative adjuvant, because they provide great stability and controlled release of associated antigens, but loading and synthesis of the particle shells is challenging and inefficient.
The present invention identifies silaffin silica particles as a carrier into which antigen particles can be loaded. Subunit vaccines are attached to silaffin peptides via covalent conjugation. The resulting conjugates are then immobilized within silica particles by simple precipitation from silicic acid solution in a biomimetic manner. This is a very simple process involving mild reaction conditions. The invention combines the strength of silica particles and peptide assemblies as adjuvants and circumvent their shortcomings in a simple production of homogeneously loaded vaccine-adjuvant combinations.
The silaffin silica particle adjuvants can be used for eliciting a therapeutic immune response against human and animal diseases that are currently challenging to treat (e.g. metastatic cancer, HIV).
Benefits:
- Controlled release of associated antigens
- Alternative to alum-based adjuvants
- May improve shelf-life, reduce necessity for cold chain
Patent protection applied for.