Previous Research

Cancer Vaccines, Immune Modulation

The goal is to recruit immune responses against tumors through a combination of vaccines and immune modulation agents, such as antibodies that block PD-1 (Programmed Death 1).

HIV Vaccines

Research to design and test prophylactic vaccines against HIV, the virus that causes AIDS. An effective vaccine should incorporate both antibody and T-cell based approaches.

Monoclonal Antibodies

  • Selection and characterization of anti-PD-1 monoclonal antibodies; non-human primate experiments
  • Discovery of CMV-specific antibodies from Morphosys phage display library
  • SPR experiments of neutralizing and non-neutralizing mAbs (e.g., HIV, Staph, Dengue)

Bioinformatics

  • Modeling and predictions of cross-clade efficacy of HIV vaccines
  • Design of optimal gene sequences for worldwide vaccines
  • Analyses of correlates of immune protection in SIV / SHIV challenge rhesus experiments
  • Bioinformatics analyses to guide vaccine sequence selection for influenza, CMV, Chikungunya programs.  Germline analyses of monoclonal antibodies.

Assay Development

  • ELISpot assay for efficient mapping of epitopes in HIV gag/pol/nef to individual 9-mer peptides
  • Multiplex Luminex assay of gag/pol/nef antibody concentrations in rhesus and human sera
  • Multiplex Luminex assay for influenza M2/HA antibody concentrations in rhesus and human sera
  • Implement in vitro HLA type-specific assays on MHC-I ↔ 9-mer peptide binding to assess affinities and off-rates, to discover potential epitopes and complement ELISpot mapping
  • Data fitting and analytical questions related to assay design and interpretation.  Member and contributor to clinical assay teams for multiple programs.

Cytomegalovirus (CMV) vaccines

Development of a vaccine against cytomegalovirus (CMV).

Gene delivery and Electroporation in vivo

  • Experiments of electroporation technology for enhanced gene expression and immunogenicity in DNA-based vaccines against cancer and HIV, in mice and non human primates.
  • Design of electric pulse generators and applicators for pre-clinical and clinical use for cancer vaccine.
  • Member of joint device team on safety assessment and clinical implementation for cancer vaccine.

Nanomaterials and Microfluidic Devices

Generation of new devices at the sub-micron length scale to manipulate and study individual cells in the laboratory.

Inorganic-Organic Hybrid Nanocomposites

Nanostructural control at the near-atomic scale of organic as well as inorganic materials is an essential feature of growth phenomena in living organisms.  In biological systems it has been achieved through long evolutionary optimization processes and is often the result of a complex interplay between a large number of constituents.  Such nanostructural control in the synthetic approach to polymer-inorganic nanocomposite materials is still a challenge.  Block copolymers can act as structure directing agents.  Morphology control is achieved by changing from conventional silicon precursors to organically modified ceramic (ormocer) precursors in the block copolymer directed synthesis.  The resulting polymer-inorganic nanocomposite materials show a unique type of interface between organic and inorganic components in which one of the blocks is entirely embedded into the inorganic phase.  This leads to a two phase system which shows very similar phase behavior as observed in phase diagrams of block copolymers and mixtures with their respective homopolymers.  With the help of transmission electron microscopy (TEM) and two-dimensional small angle x-ray scattering (SAXS) we have demonstrated the existence of a whole range of block copolymer microstructures for the polymer-inorganic nanocomposites, particularly bicontinuous cubic structures in which the polymer phase is the minority component.  Subsequent calcination leads to mesoporous materials which have potential applications in the fields of catalysis, separation technology and microelectronics.

Electrochemical Deposition of Single Atomic Monolayers

Simultaneous time-resolved measurements of the charge transfer and x-ray scattering during the phase transition. This is a transition between a phase with a single layer of copper atoms adsorbed on a surface and a phase where some of those atoms has been desorbed. We examined the desorption and subsequent nucleation of islands of the new phase.

Charge-Density Waves

A charge-density wave (CDW) is a low temperature phenomenon which creates a standing longitudinal wave in the crystal. Once, CDWs were believed to be good models for superconductivity. While that is no longer true today, they are still ideal systems for understanding certain types of physical problems, and interesting systems in their own right. We studied CDWs through simultaneous kinetic x-ray scattering and electronic measurements.

Professor Rob Thorne has written a good introduction (PDF) in Physics Today, and introductory slides (powerpoint).

Electronic states at semiconductor-metal interfaces Surfaces

Schottky Band-bending at the interface of gallium-arsenide (a common semiconductor) and aluminum.  A nicely done tutorial has been written by Professor Tung.at CUNY.  Explanation of band bending and metal-induced gap states on Wikipedia.