Overview

The Radiochemistry Support Group develops radiochemical methods to produce radiotracers for in vivo imaging in HIV studies, and chemical and biochemical methods to synthesize, identify, and characterize the radiolabeled antibody, cytokine, and small molecular probes. 

We develop radiotracers to support noninvasive, in-vivo whole-body imaging in healthy and SIV/SHIV-infected nonhuman primates. The group uses single photon emission-computed tomography or positron emission tomography, nuclear imaging techniques that use radioactive substances injected into animals to provide images of the body.  

We target antibodies, cytokines, or peptides by radiolabeling them with gamma emitters or positron emitters through appropriate chelating agents. The group also performs biochemical and radiochemical analysis and pharmacokinetic studies, including: 

  • analysis of the radiotracers and their metabolites in the biological specimens after administration 

  • in vivo and in vitro stability tests 

  • in vitro immunogenicity test 

  • ex vivo autoradiography 

Our work supports the AIDS Imaging Research Section in the Division of Clinical Research at the National Institute of Allergy and Infectious Diseases. 

Focus

Anti-CD4 antibodies imaging 

  • Radiolabel different anti-CD4 monoclonal antibodies with positron emitters.  
  • Perform immunogenicity tests. 
  • Test cross-reactivity between radiolabeled anti-CD4 mAbs. 
  • Support in vivo positron emission tomography imaging for comparing the uptakes by the different anti-CD4 mAbs using gamma or positron emitters. 

Antiviral drug delivery by lipid-based nanoparticle 

  • Develop and optimize radiolabeling methods for lipid or antiviral drugs using gamma or positron emitters. 
  • Evaluate purification methods.  
  • Perform in vitro stability tests.  
  • Support in vivo imaging. 

Anti-ENV antibodies imaging 

  • Radiolabel anti-ENV antibodies with positron to detect the SIV ENV expression in vivo
  • Identify endogenous mAbs developed by viral infection. 
  • Provide in vivo positron emission tomography imaging support.