Interaction studies between human papillomavirus virus-like particles and laminin 332 by affinity capillary...

Area of Science:

• Biochemistry
• Virology
• Extracellular Matrix Research

Background:

• Human papillomavirus (HPV) is known to interact with extracellular matrix components.
• Laminin 332 (LN332) is a crucial protein in the extracellular matrix, involved in cell adhesion and tissue structure.
• Understanding the molecular interactions between HPV and LN332 is important for comprehending viral entry and pathogenesis.

Purpose of the Study:

• To investigate and quantify the binding properties between HPV and LN332.
• To determine the kinetic parameters (association and dissociation rates) of the HPV-LN332 interaction.
• To assess the binding affinity of HPV to LN332 under physiological conditions.

Main Methods:

• Bio-layer interferometry (BLI) was employed to measure VLP binding and release kinetics.
• Affinity capillary electrophoresis (ACE) was developed to study the interaction in solution without labeling.
• HPV16 virus-like particles (VLPs) and purified LN332 were used as model interactants.

Main Results:

• BLI analysis yielded an average association rate constant (k_on) of 1.74 x 10⁴ M^-1s^-1 and a dissociation rate constant (k_off) of 1.50 x 10^-4 s^-1.
• ACE demonstrated a decrease in HPV16-VLP complex mobility with increasing LN332 concentrations, indicating binding.
• Both BLI and ACE approaches reported an apparent equilibrium dissociation constant (K_d) in the nanomolar range (8.89 nM and 17.7 nM, respectively).

Conclusions:

• The study quantitatively characterizes the interaction between HPV16 VLPs and LN332.
• The nanomolar binding affinity suggests a stable interaction relevant to HPV's extracellular matrix interactions.
• These findings provide insights into the molecular mechanisms underlying HPV binding to LN332.