Seminar: C. elegans as a High-Throughput System for Chemical and Genetic Screens to Explore Neural-Immune Communications

Speaker:
Alejandro Aballay, PhD
Associate Professor
Department of Molecular Genetics & Microbiology
Duke University Medical Center, U.S.A.

Host:
Patrick Casey, Ph.D.
Professor & Senior Vice Dean of Research
Duke-NUS Graduate Medical School, Singapore

Date:
Wednesday, August 31, 2011

Time:
12pm to 1pm

Venue:
Amphitheatre, Level 2
Duke-NUS Graduate Medical School
8 College Road, Singapore 169857
(opposite Singapore General Hospital, Block 6/7)

Contact:
Dolliss 65167251

Synopsis:
Activation of the innate immune system upon pathogen recognition results in a rapid and definitive microbicidal response to invading microorganisms which needs to be fine-tuned as deficiencies or excesses in the response have deleterious effects. While insufficient immune responses can lead to infection and cancer, excessive immune responses have been linked to conditions such as Crohn’s disease, rheumatoid arthritis, atherosclerosis, diabetes, and Alzheimer’s disease. The nervous system, which can respond in milliseconds to many types of nonspecific environmental stimuli, has several characteristics that make it an ideal partner with the innate immune system to regulate the magnitude of immune responses. To provide insights into the neural mechanisms that regulate innate immunity, we have taken advantage of the simple and well-studied nervous and immune systems of the nematode Caenorhabditis elegans. We have demonstrated that specific neurons control innate immunity in the intestinal cells of C. elegans, in part by regulating a mitogen-activated protein kinase signaling pathway similar to the mammalian p38 MAPK pathway and by regulating the expression of non-canonical unfolded protein response genes. Overall, our studies highlight pathways that may play important roles at dealing with pathogens directly and with the damages caused by the infection. In addition, the discovery that inactivation of a neuronal pathway that is involved in the arousal response activates immunity suggest that there is a strong selective advantage to suppressing immune responses during anger/acute stress.

Biography: 
Alejandro Aballay earned his bachelor's degree in Pharmacy from Juan A. Maza University, in Mendoza, Argentina, in 1994. He finished his M.S. equivalent studies in 1995 and started exploring the machinery that governs early steps in endocytosis at Nacional de Cuyo University. In 1998, he earned his Ph.D. at Nacional de Cuyo Univ and received a Pew Fellowship to move to St. Louis, where he continued his studies in endocytosis at Washington University. In 1999, following an interest in bacterial pathogenesis he developed while studying the intracellular transport of Brucella abortus, and he moved to Boston to join the Ausubel laboratory at Harvard Medical Sch.  Dr. Aballay moved to Durham in 2002 to join the Dept of Molecular Genetics and Microbiology, where his studies focus on what makes bacteria pathogenic and hosts resistant.

Dr. Aballay's lab takes advantage of the compromise between complexity and tractability of the C. elegans-S. enterica pathogenesis model. The focus of the laboratory is to use C. elegans as a host to screen thousands of bacterial clones from mutagenized libraries to identify novel Salmonella virulence factors and to address how they alter host signaling pathways. His group is also exploiting the genetic and genomic resources available for C. elegans to study the basis of the immune response.

Dr. Aballay is a recipient of the 2005 ICAAC Young Investigator Award. Dr. Aballay also serves as an editor for the journal PLoS One, a new open access journal from the Public Library of Science, and serves on the editorial board for Virulence.