Category: Automation and High-Throughput Technologies
The increase in prevalence and geographic range for numerous pathogenic viruses and bacteria poses a significant threat to public health due to the insufficient medical countermeasures available. The most recent outbreaks of Zika virus, B. mallei, Ebola virus, and other pathogens highlight the need for integration of viral and bacterial assays in Biosafety Levels 2, -3, and -4 into an efficient screening process enabling evaluation of small molecules, siRNAs, antibodies and other biologics as potential anti-viral or anti-bacterial therapeutics.
The Therapeutic Development Center (TDC) at the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) in support of drug discovery effort has implemented a High Content Screening (HCS) approach that utilizes state-of-the-art multidisciplinary technologies. HCS has the potential to discover compounds that modulate relevant biological processes in an unbiased target-and-mechanism-agonistic fashion. The integration of high-content imaging (HCI), automated liquid handling, compound tracking, numerous cell types, and the ability to test multiple BSL-2, -3, and -4 pathogens provides a flexible screening platform with unique capabilities.
The screening process begins with cell seeding into 96-, 384-, or 1536-well assay plates using a Thermo Fisher Combi Multi-drop. Compound treatment is completed with a combination of automation workstations, including a Perkin Elmer (PE) Janus MDT/Varispan, Hewlett-Packard (HP) D300 Digital Dispenser, Thermo Fisher Combi Multi-Drop, and Biomek FXP. Infection occurs within BSL-2, -3, or -4 labs with the use of Integra Viafill. Pathogens are incubated in cell culture for a specified time prior to formalin fixation. Immunostaining of fixed cells is performed using a BioTek EL406. A confocal PE Opera with PE Acapella algorithms is programmed for acquisition and analysis of images in order to determine percent viability and infection. A robotic arm and large capacity plate carousel allows for constant operation without user intervention. Data analysis is done using Columbus, Genedata, and Spotfire. This provides information for quality control and further data analysis. Assessment of effectiveness for the tested compounds is done using GeneData curve fitting algorithms that provide potency (EC50) and toxicity (CC50) values.
Throughout this process, an in-house plate tracking program, Metadata Management System (MMS), ensures user coordination for proper cell plating, treatment, infection, fixation, staining, and imaging timing with the use of high-quality record-keeping. This instrumentation provides flexibility in compound quantity, concentration, and pathogens that can be tested simultaneously.
Glenn Gomba– Laboratory Automation Technician, USAMRIID, Fairfield, Pennsylvania
Laboratory Automation Technician
Glenn Gomba is a Laboratory Automation Technician in the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) Molecular and Translational Sciences division; with experience in molecular/cellular biology, numerous screening automation workstations, and assay development.
In 2010, Glenn began work at USAMRIID and has participated in many projects, presenting work at Toxins and Interagency Botulism Research Coordinating Committee conferences and coauthor on three publications. With the support of a fellowship program from Oak Ridge Institute for Science Education, Glenn graduated from Frederick Community College in 2012 with an AS in Chemistry followed by a BA in Biochemistry from Hood College in 2016.