Penn IMIG

Description of Penn IMIG Expertise

Research:

Research in the Baumgart lab is primarily focused on the biophysics of biologically relevant membranes. Experimental systems of interest include membranes self-assembled from synthetic or purified lipids or diblock-copolymer amphiphiles, membranes purified from biological cells, and membranes of whole cells.

In particular, work focuses on:

• The characterization of curvature sensing and curvature generating peripheral membrane binding proteins such as amphiphysin and endophilin, along with protein domains, such as ENTH and BAR. This work combines the use of micropipette aspiration techniques and optical tweezers with laser scanning fluorescence microscopy.

• The biophysics of signal cluster formation and function in T-cells stimulated by complex surfaces. This project employs fluorescence wide-field, regular total internal reflection microscopy and photo-activation localization microscopy to study T-cells stimulated by ligand surfaces with varying mobilities and surface patterns.

• The elucidation of physicochemical aspects of amphiphile membranes with phase coexistence.  Particular areas of interest include the partitioning of membrane proteins among liquid ordered and liquid disordered phases, properties associated with phase boundaries, and aspects of mixing / demixing phase transitions.

Lab expertise and resources:

• Micropipette aspiration of giant unilamellar vesicles and polymersomes


• Force measurements using an optical trapping system


• Dual-color TIRF of living cells


• Photoactivation localization microscopy (PALM) of fixed and live cells


• Matlab image processing

IMIG Collaborations:

• Baumgart, Burkhardt, and Koretzky: immune cell/patterned surface interactions

Lab members:

• Ben Capraro – Graduate student
  
  
  
  • Membrane-curvature sensing proteins
  
  
  • capraro@sas.upenn.edu
    
    
  
  
  
  


• Marcela Carmona – Undergraduate
  
  
  
  • Receptor cross-linking on immune cells
  
  
  • carmona@sas.upenn.edu
    
    
  
  
  
  


• Cinzia Esposito – Post-doctoral Fellow
  
  
  
  • Membrane-active peptides
  
  
  • cinzia.esp@gmail.com
    
    
  
  
  
  


• Michael Heinrich – Graduate student
  
  
  
  • Mechanical properties of lipid membranes
  
  
  • heinric@sas.upenn.edu
    
    
  
  
  
  


• Wan-Ting Hsieh – Graduate student
  
  
  
  • Lipid monolayers and bilayers
  
  
  • hsiehw@sas.upenn.edu
    
    
  
  
  
  


• Chih-Jung Hsu – Graduate student
  
  
  
  • T-cell signaling, microclusters
  
  
  • chijung@sas.upenn.edu
    
    
  
  
  
  


• Sarah Johnson – Undergraduate
  
  
  
  • Calcium signaling of immune cells
  
  
  • johnsa@sas.upenn.edu
    
    
  
  
  
  


• Aiwei Tian – Graduate student
  
  
  
  • Material properties of polymer and lipid membranes
  
  
  • aiwei@seas.upenn.edu
    
    
  
  
  
  


• Abraham Waldman – Undergraduate
  
  
  
  • Molecular cloning
  
  
  • abrahamw@sas.upenn.edu
    
    
  
  
  
  


• Ting-Ting Wu – Graduate student
  
  
  
  • Immune cells on patterned surfaces
  
  
  • tintwu@sas.upenn.edu
    
    
  
  
  
  


• Chen Zhu – Graduate student
  
  
  
  • Physical chemical properties of tubular membranes
  
  
  • chenzhu@sas.upenn.edu