Joint Fellowship Training Program
Mentor:
Indira Hewlett, Ph.D
Organizational Affiliation and Position:
Chief, Laboratory of Molecular Virology, Division of Emerging and Transfusion Diseases, Office of Blood Research and Review, Center for Biologics Evaluation and Research (CBER), FDA
Email:
indira.hewlett@fda.hhs.gov
Phone:
301-827-0795
Running Title of Program:
Application of a novel, multiplex nanoparticle based Bio-barcode amplification assay for detection of major blood borne and biodefense pathogens as well as cancer biomarkers.
Research Project Summary:
A primary goal of FDA is to bring new technologies including better methods that are rapid, more accurate, and less expensive to disease screening and diagnosis. An exciting, new, ultra sensitive technique based on nanotechnology referred to as Bio-barcode amplification (BCA) has been developed to detect attomolar concentrations of antigens and nucleic acids. The technique is considered to be easier, faster, more accurate and cost-effective than polymerase chain reaction (PCR). It is particularly suitable for multiplexed, simultaneous detection of multiple pathogens in a single sample. In the work funded by FDA intramural funds during the last fiscal year we proposed to develop and validate the BCA Nanoparticle assay for HIV, a blood borne virus and the cause of AIDS, as proof of concept. In collaboration with Dr. Chad Mirkin (Northwestern University), a BCA-RNA and BCA-protein assay have been set up to detect HIV-1 RNA and HIV-1 capsid protein (p24), respectively. Our preliminary results showed that without PCR amplification, 1.5 copy of HIV-1 RNA could be detected by our BCA-RNA assay while 10pg of HIV-1 capsid protein was detected by the BCA-protein assay. We are now further optimizing the conditions to make the assays repeatable, more sensitive and specific. With additional funding for the second year, we intend to extend this technique to other pathogens of relevance to FDA's public health mission including West Nile virus (WNV), Hepatitis B virus (HBV), hepatitis C virus (HCV), Y. pestis, a biodefense pathogen and M. tuberculosis, a significant co-infection in AIDS. We will evaluate the feasibility of developing a multiplex assay to simultaneously detect these pathogens in a single sample. The proposed project will benefit FDA in the following ways: 1) it will give FDA scientists involved in regulating diagnostics hands-on expertise and knowledge of how to regulate related products since BCA tests and other nanotechnology-based assays could be available for use in public health settings in the near future 2) laboratory experience with the nanoscale technology should enable FDA scientists to develop review criteria and standards for effective regulation of product applications of future nanoscale assays.
Proposed project for IOTF fellow:
The fellow will be involved with development and optimization of the nanoparticle-based assays for detection of HIV and hepatitis viruses. In addition, the nanoparticle-based assay technology will be extended to detection of serum biomarkers using single and multiplexed diagnostic assays for early detection of epithelial cancers.
Regulatory Activity:
The fellow would be involved in review of diagnostic (nucleic acid) assays for HIV and WNV. Laboratory experience with nanoparticle based diagnostics will provide the fellow with knowledge that would help in defining validation methods for nanoscale diagnostics.
