Ordered mesoporous silicas for potential applications in solid vaccine formulations

Author(s):Show less -

Miranda, Matheus C. R. ; Nunes, Carmen M. ; Santos, Luana F. ; da Silva, Leonardo B. ; de Jesus, Vinicius R. ; Andreo Filho, Newton ; Pedro, Jessica A. F. ; Lopes, Jose L. S. ; Oliveira, Cristiano L. P. ; Fantini, Marcia C. A. ; Cardoso, Jessica S. ; Trezena, Aryene G. ; Ribeiro, Orlando G. ; Sant'Anna, Osvaldo A. ; Tino-De-Franco, Milene ; Martins, Tereza S.

• Document type: Journal article
• Source: Vaccine; v. 42, n. 3, p. 12-pg., 2024-02-01.

Abstract

In an effort to develop efficient vaccine formulations, the use of ordered mesoporous silica (SBA -15) as an antigen carrier has been investigated. SBA -15 has required properties such as high surface area and pore volume, including narrow pore size distribution to protect antigens inside its matrix. This study aimed to examine the impact of solvent removal methods, specifically freeze-drying and evaporation on the intrinsic properties of an immunogenic complex. The immunogenic complexes, synthesized and incorporated with BSA, were characterized by various physicochemical techniques. Small Angle X-ray Scattering measurements revealed the characteristic reflections associated to pure SBA -15, indicating the preservation of the silica mesostructured following BSA incorporation and the formation of BSA aggregates within the macropore region. Nitrogen Adsorption Isotherm measurements demonstrated a decrease in surface area and pore volume for all samples, indicating that the BSA was incorporated into the SBA -15 matrix. Fluorescence spectroscopy evidenced that the tryptophan residues in BSA inside SBA -15 or in solution displayed similar spectra, showing the preservation of the aromatic residues' environment. The Circular Dichroism spectra of BSA in both conditions suggest the preservation of its native secondary structure after the encapsulation process. The immunogenic analysis with the detection of antiBSA IgG did not give any significant difference between the non -dried, freeze-dried or evaporated groups. However, all groups containing BSA and SBA -15 showed results almost three times higher than the groups with pure BSA (control group). These facts indicate that none of the BSA incorporation methods interfered with the immunogenicity of the complex. In particular, the freeze-dried process is regularly used in the pharmaceutical industry, therefore its adequacy to produce immunogenic complexes was proved Furthermore, the results showed that SBA -15 increased the immunogenic activity of BSA. (AU)

• FAPESP's process: 19/08582-5 - Multi-User Equipment approved in grant 17/17844-8: thermal analyzer - TG/DTA model sta 2500 TG/DTA room temperature to 1100 °c
• Grantee: Tereza da Silva Martins
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 22/08360-5 - Study of the influence of the morphological properties of SBA-15 on the efficacy of molecules with therapeutic potential and vaccines
• Grantee: Matheus Carlos Romeiro Miranda
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 19/19567-7 - Structural studies of proteins incorporated in ordered mesoporous silica
• Grantee: Jéssica Aparecida Ferreira Pedro
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 22/01951-8 - Study of the chemical and structural integrity of virus-like particles and their incorporation into ordered mesoporous silica
• Grantee: Jose Luiz de Souza Lopes
• Support Opportunities: Research Grants - Initial Project