Human papillomavirus (HPV) is the most common sexually transmitted infection (STI) in the United States. There are 14 high-risk types of HPV that can cause various cancers of the cervix, penis, oropharynx, vulva, and vagina. The current HPV vaccine, Gardasil 9, protects against 7 types that can cause cancer and 2 types that can cause warts. The limited coverage is concerning because uncovered cancer-causing types are found at higher prevalence within certain Native American communities. Thus, vaccines that cover more cancer-causing types of HPV are extremely important to Native American communities and the country.

Self-assembling peptides display hydrophobic and hydrophilic amino acid side chains. In polar solutions, these peptides spontaneously form β-sheets which laminate into fibrils that expose the hydrophilic side chains. KFE8 (Ac-FKFEFKFE -NH2) is an emerging self-assembling peptide that has high thermostability. This project aims to understand the biophysics of KFE8’s self-assembling properties, while testing its effectiveness as a vaccine antigen platform for HPV.

KFE8 was synthesized using a Prelude synthesizer with standard Fmoc solid phase procedures. High Pressure Liquid Chromatography (HPLC) was used to assess the purity of the peptide. Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) was used to confirm the molecular weight of the peptide. The peptide was placed in water and sonicated to induce β-sheet formation. Circular Dichroism (CD) was used to confirm successful fibrilization and to assess the thermostability of the synthesized peptide. The HPV linker was conjugated onto the KFE8 fibril using standard SMPH procedures. MALDI-TOF was used to assess successful conjugation. Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM) were used to visualize the KFE8 fibrils and conjugated fibrils.

HPLC and MALDI-TOF showed that the synthesized KFE8 had the correct molecular weight and was pure. CD confirmed successful fibrilization after sonication. MALDI-TOF confirmed successful conjugation of HPV linker onto KFE8 fibrils. AFM and TEM visually confirmed and characterized non-conjugated and conjugated fibrils.

KFE8 was able to be successfully synthesized and create fibrils. HPV linkers and KFE8 fibrils were able to successfully conjugate. Future studies will continue to assess the viability of KFE8 and explore the placement of HPV antigens along the fibril surface.

Naomi Lee

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