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

SIV/SHIV imaging support 

We develop radiotracers to support noninvasive, in vivo, whole-body imaging in healthy and simian immunodeficiency virus (SIV)/simian-human immunodeficiency virus (SHIV)–infected nonhuman primates. Our work supports the AIDS Imaging Research Section in the Division of Clinical Research at the National Institute of Allergy and Infectious Diseases.  

Radiolabeling for nuclear imaging scan 

Our group performs radiolabeling for nuclear imaging scan — single-photon emission-computed tomography (SPECT) and positron emission tomography (PET) — that utilize injected radioactive tracers to localize specific binding sites in the body. We target antibodies, cytokines, or peptides to radiolabel with gamma (99mTc, 111In, 123I etc.) or positron (89Zr, 64Cu, etc.) emitters.

Single-photon emission-computed tomography (SPECT) room of Radiochemistry Support Group
Image of single-photon emission-computed tomography (SPECT) room.
Room with equipment
Emission tomography (PET) scan room.
laboratory bench
Radiochemistry Support Group laboratory bench space.

Our capabilities and specializations

Radiolabeling of anti-CD4 antibodies

Anti-CD4 antibodies are radiolabeled with gamma or positron emitters for imaging the CD4+ T-cell pool in control and infected rhesus macaques. Antibodies are used as an intact or fragments (Fab or F(ab´)2) and chelated with bifunctional chelators depending on the radionuclides.

  • Immunogenicity testing 

  • Cross-reactivity testing of radiolabeled anti-CD4 mAbs 

Anti-ENV antibody imaging 

We identify SIV virus reservoirs and anatomical foci of viral transcriptional activity using radiolabeled anti-envelope monoclonal antibodies in non-infected, acutely infected, and chronically infected rhesus macaques. The anti-ENV antibodies — murine, primatized, or humanized — are also used as an intact, or fragmented and radiolabeled for SPECT or PET scan.

  • Identification of endogenous mAbs developed via viral infection  

  • In vivo PET imaging support 

Radiolabeling of lipid-based nanoparticles

We develop and optimize radiolabeling methods for liposome or lipid-based nanoparticle to deliver antiretroviral drugs that have been used to extend the life span of the HIV-infected patients.

  • In vitro stability testing 

  • In vivo imaging