Biomechanical characterization of Ebola virus-host cell interaction
Advisor: Frank Zhang
View: UGRS Research Poster (PDF)
Since the most recent outbreak in 2014, the Ebola virus (EBOV) epidemic has become one of the world’s major public health and safety concerns. EBOV is a single-stranded, negative-sense RNA virus that can infect humans and primates and cause hemorrhagic fever. It has been proposed that the T-cell immunoglobulin and mucin domain (TIM) family proteins act as cell surface receptors for EBOV, and that the interaction between TIM and phosphatidylserine (PtdSer) on the surface of EBOV mediates the EBOV-host cell attachment (1). Despite these initial findings, the biophysical properties of the TIM-EBOV interaction, such as the mechanical strength of TIM-PtdSer bond that allows the virus-cell pair to resist external mechanical perturbations, have not yet been characterized. This study utilizes an atomic force microscope (AFM), a highly sensitive detection tool, to quantify the specific interaction forces between EBOV and TIM proteins, and thereby to uncover the biophysical mechanisms underlying EBOV-host cell interactions. This was achieved by the means of single molecule force spectroscopy, a method where a single bond rupture between two proteins can be measured directly. The force spectroscopy was performed under multiple conditions: TIM-1 v. PtdSer, TIM-4 v. PtdSer, TIM-1 v. EBOV virus like particle (VLP) and TIM-4 v. EBOV VLP. Further force spectroscopy was carried out on model system where HEK 293T cells were transfected with TIM-1 or TIM-4. Based on a dynamic force spectrum (DFS) and Bell-Evans model analysis, the results suggest that TIM-EBOV interactions are mechanically comparable to antibody-antigen interactions, and that TIM-4/ligand interaction is more resistant to force making TIM-4 the more likely pathway for EBOV infection.
1. Moller-Tank S, Albritton LM, Rennert PD, Maury W. Characterizing functional domains for TIM-mediated enveloped virus entry. Journal of virology. 2014;88(12):6702-13. doi: 10.1128/JVI.00300-14. PubMed PMID: 24696470; PubMed Central PMCID: PMC4054341.
About Michelle Sanabria:
Michelle Sanabria graduated last year with a B.A. with high honors in Music (Composition and Theory) and will complete her B.S. in Bioengineering (Biomechanics and Biomaterials) this semester. She has been conducting research using atomic force microscopy (AFM) in Professor Zhang’s laboratory since 2014. She is focusing her current research on gaining a better understanding of the uptake of Ebola into the host cell. Last summer, under the direction of Dr. Emilios Dimitriadis, she was a fellow at the National Institutes of Health (NIBIB), where she used AFM technologies for the imaging and characterization of protein-DNA complexes and analyzed both the images and force curves with ImageJ and Matlab. Additionally, Michelle is a member of the University Choir, an alumna of Alpha Gamma Delta, and was music director of the Lehigh Melismatics a cappella group for three years. Upon graduation, Michelle will continue her education at Lehigh, pursuing a Master of Science in Management for further career development.