Principal Investigator: Robert Duncan, PhD
Office / Division / Lab: OBRR / DETTD / LEP

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General Overview

OBRR performs regulatory evaluation of in vitro diagnostic devices used to screen for infectious microorganisms in blood donations. Currently, this screening is done for only a few specific, pathogenic (disease-causing) microorganisms that public health officials consider the biggest threats to blood safety.

However, there are no donor screening tests for several other pathogens that are uncommon, are transmitted only at certain times of the year, or that occur only in certain areas of the country. Nonetheless these pathogens can be transmitted and cause disease—sometimes fatal—following transfusion in vulnerable populations (newborns, the elderly and those whose immune system is weak).

In addition, over time, certain pathogens may acquire sufficient genetic changes that render them undetectable to existing tests licensed for screening donated blood. This would require modification of existing tests or addition of new ones to detect the altered pathogens.

Fortunately, there is a solution to this growing threat to the blood supply: recent advances in technologies for identifying the genetic makeup of cells and microorganisms, combined with so-called "multiplex platforms" that incorporate such methods into devices that enable very rapid detection of several different pathogens simultaneously. These technologies might simplify routine donor screening of many pathogens, including those that have acquired variations.

To stay abreast of this developing technology and facilitate its advancement, the Division of Emerging and Transfusion Transmitted Diseases (DETTD) established a new program of research and evaluation in the Laboratory of Emerging Pathogens (LEP). This new program encompasses using new technologies and combinatorial approaches to detect simultaneously known blood-borne pathogens to enhance blood safety and availability.

This research program aims to carry out the following OBRR Research Priority: "Evaluate and adapt emerging technologies for high sensitivity detection and novel reduction methods for infectious agents in blood and blood products."

The goal is to identify and test new and better ways to use multiplex devices to detect blood-borne pathogens and to use those devices to investigate how those pathogens cause disease. Therefore, this program addresses the following goal listed in the FDA Strategic Plan for Regulatory Science Priorities: "FDA will develop necessary expertise and infrastructure to evaluate new and emerging technologies through active intramural research and collaboratively with external partners."

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Scientific Overview

Our strategy is to use and evaluate promising new nucleic acid-based detection technologies that could enhance the safety of the blood supply.

We will use our expertise in—and access to—blood-borne pathogens, to evaluate new platforms for detection of pathogen-spiked human blood and plasma specimens. Moreover, we will leverage the equipment and expertise of outside companies through contracts and collaborations as the most cost effective way to evaluate these new technologies. Platforms will undergo final testing using repository blood donor specimens.

The principle investigator has studied new pathogen detection technology since 2000 and has published studies on the use of advanced technology to detect blood-borne pathogens (a Leishmania donovani genomic microarray, a microarray for pathogen detection, PCR-based species identification, and a multiplex real-time PCR platform).

Our laboratory conceived of the OpenArray multiplex real time PCR platform project, optimized it with spiked specimens and validated it with repository specimens of infected blood donors obtained from Creative Testing Solutions.

The laboratory is also evaluating the TessArae Resequencing Pathogen Microarray for its potential in multiplex blood donor screening. It is now evaluating a custom-designed Blood Borne Pathogen Resequencing Pathogen Microarray (BBP-RPM) version 2 for improved identification of pathogens in blood.

The laboratory is now establishing and validating standardized methods for spiking rare pathogens in blood to create specimens for testing new diagnostic devices. The standardized methods will be posted on the National Institute for Allergy and Infectious Diseases (NIAID) website for the use of device developers.

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Publications

J Mol Diagn 2014 Jul;16(4):379-81
Advancing molecular diagnostics for trypanosomatid parasites.
Duncan R

PLoS Negl Trop Dis 2014 Feb 20;8(2):e2707
Deletion of ubiquitin fold modifier protein Ufm1 processing peptidase Ufsp in L. donovani abolishes Ufm1 processing and alters pathogenesis.
Gannavaram S, Davey S, Lakhal-Naouar I, Duncan R, Nakhasi HL

J Mol Diagn 2014 Jan;16(1):136-44
Multiplex screening for blood-borne viral, bacterial, and protozoan parasites using an OpenArray platform.
Grigorenko E, Fisher C, Patel S, Chancey C, Rios M, Nakhasi HL, Duncan RC

J Infect Dis 2013 Apr;207(8):1328-38
A New Model of Progressive Visceral Leishmaniasis in Hamsters by Natural Transmission via Bites of Vector Sand Flies.
Aslan H, Dey R, Meneses C, Castrovinci P, Jeronimo SM, Oliva G, Fischer L, Duncan RC, Nakhasi HL, Valenzuela JG, Kamhawi S

J Immunol 2013 Mar 1;190(5):2138-49
Live attenuated Leishmania donovani p27 gene knockout parasites are nonpathogenic and elicit long-term protective immunity in BALB/c mice.
Dey R, Dagur PK, Selvapandiyan A, McCoy JP, Salotra P, Duncan R, Nakhasi HL

Mol Microbiol 2012 Oct;86(1):187-98
Deletion of mitochondrial associated ubiquitin fold modifier protein Ufm1 in Leishmania donovani results in loss of beta-oxidation of fatty acids and blocks cell division in the amastigote stage.
Gannavaram S, Connelly PS, Daniels MP, Duncan R, Salotra P, Nakhasi HL

J Trop Med 2012;2012:631460
Immunity to visceral leishmaniasis using genetically defined live-attenuated parasites.
Selvapandiyan A, Dey R, Gannavaram S, Lakhal-Naouar I, Duncan R, Salotra P, Nakhasi HL

Antimicrob Agents Chemother 2012 Jan;56(1):518-25
Downregulation of mitogen-activated protein kinase 1 of Leishmania donovani field isolates is associated with antimony resistance.
Ashutosh, Garg M, Sundar S, Duncan R, Nakhasi HL, Goyal N

Mol Biol Int 2011;2011:428486
Identification and Characterization of Genes Involved in Leishmania Pathogenesis: The Potential for Drug Target Selection.
Duncan R, Gannavaram S, Dey R, Debrabant A, Lakhal-Naouar I, Nakhasi HL

PLoS One 2011 Jan 14;6(1):e16156
Mitochondrial Associated Ubiquitin Fold Modifier-1 Mediated Protein Conjugation in Leishmania donovani.
Gannavaram S, Sharma P, Duncan RC, Salotra P, Nakhasi HL