Biology subjects

Kan, M.-C.

Publications and source records attributed to Kan, M.-C..

4 recordsLinked to original sources

bioRxiv2023

Adjuvant Effects of Amphipathic Helical Peptides

Subunit vaccines are the focus of research in developing new vaccines against infectious diseases. Due to the low immunogenicity of recombinant proteins, adjuvants are required for the activation of humoral and cellular immunity against a protein antigen. In this study, we reported the identification of a novel pathway that can activate humoral immunity against a recombinant protein without inducing inflammatory responses. By fusing an amphipathic helical peptide to GFP, one can increases the immunogenicity of GFP by up to 1000 fold. This enhancement was correlated with the ability of amphipathic helical peptides to bind to cell membranes and cause lysosomal membrane permeabilization. We showed evidence that the amphipathic helical peptide may induce the delivery of antigen across the lysosomal membrane into cytosol. Amphipathic helical peptide fusion provided a new pathway for stimulating immune responses against recombinant proteins.

immunology↗

bioRxiv2023

The thermostability of a VADEX-Pro based protein nanoparticle

We have adapted split GFP technology into the protein nanoparticle platform, Vaccine Delivery system X (VADEX), created in previous study. To evaluate the capability of this new platform, a model protein, maltose binding protein (MBP), was fused to the {beta}-strand 11 of sfGFP and co-expressed with VADEX-10 which was composed of LYRRLE peptide and N-terminal part up to {beta}-strand 10 of sfGFP. When these two fusion proteins were expressed in a cell, they were assembled into PNP spontaneously with a dynamic light scattering (DLS) particle size of 26 nm. This nanoparticle platform was renamed as VADEX-Pro for its capacity of expressing large protein on PNP. The thermostability of the assembled PNP was verified by both SDS-PAGE and DLS analysis following treatment. This PNP was stable at 25 {degrees}C and at temperatures as high as 40 {degrees}C for at least two months. Mutations that replaced cysteine residue of the LYRRLE peptide with serine or alanine destabilized and induced degradation of the VADEX-based PNP. The results in this study showed that the non-covalent complementation of split sfGFP became irreversible when reconstituted sfGFP was assembled in a VADEX-Pro PNP. This platform may be applied in developing thermostable vaccines.

bioengineering↗

bioRxiv2022

A thermally stable protein nanoparticle that stimulates long lasting humoral immune response

Thermally stable vaccine platform is considered to be the missing piece of vaccine technology. In this article, we are reporting the development of a novel protein nanoparticle and evaluating its ability in withstanding extended high temperature incubation and stimulating long lasting humoral immune response. This protein nanoparticle is assembled from a fusion protein composed of an amphipathic helical peptide derived from M2 protein of H5N1 influenza virus (AH3) and a super folder green fluorescent protein(sfGFP). The proposed structure of this protein nanoparticle is modeled according to transmission electronic microscope (TEM) images of protein nanoparticle. From this proposed protein model, we have generated a mutant with two gain-of-function mutations that function synergistically on particle stability. Protein nanoparticle assembled from this gain-of-function mutant is able to remove a hydrophobic patch from the surface of protein nanoparticle. This gain-of-function mutant also contributes to higher thermostability of protein nanoparticle and stimulates long lasting humoral immune response after single immunization. This protein nanoparticle shows increasing particle stability in higher temperature and higher salt concentration. This novel protein nanoparticle may serve as a thermal-stable platform for vaccine development.

immunology↗

bioRxiv2020

A self-assembled protein nanoparticle serving as a one-shot vaccine carrier

In this paper, we are exploring the role of an amphipathic helical peptide in mediating the self-assembly of a fusion protein into a protein nanoparticle and the application of the nanoparticle as a one-shot vaccine carrier. Out of several candidates, an amphipathic helical peptide derived from M2 protein of type A influenza virus is found to stimulate high antigenicity when fused to a fluorescent protein genetically. This fusion protein was found to form protein nanoparticle spontaneously when expressed and purified protein stimulates long-lasting antibody responses in single immunization. Through modeling peptide structure and nanoparticle assembly, we have improved this vaccine carrier in complex stability. The revised vaccine carrier is able to stimulate constant antibody titer to a heterologous antigen for at least six months in single immunization. The immune response against a heterologous antigen can be boosted further by additional immunization in spite of high immune responses to carrier protein.

immunology↗