Varsha Singh
Indian Institute of Science, Bangalore, India
INTRODUCTORY TALK
Recognition of microbial products in multicellular organisms: Role of nervous system
Multi cellular organisms recognize microbe associated molecular patterns via the use of pattern
recognition receptors or PRRs. They can also recognize damage associated molecular patterns or
DAMPs released as a result of sterile injury or infection. Many of these are recognized by resident
phagocytic cells in various tissues, or by circulating macrophages. Recognition of microbial products
and DAMPs in the nervous systems is an important aspect of immune surveillance in vertebrates as
well as invertebrates and may be very relevant in health certain pathological situations. Studies from
invertebrates such as Caenorhabditis elegans, and in mammals point to importance of both sensory
neurons and glia in surveillance.
RESEARCH TALK
Survival of Caenorhabditis elegans in the wild: Role of sensory neurons in avoidance behavior and
innate immunity
How does a bacterivore defend itself from pathogenic microbes? C. elegans lives in soil, close to
dead or decaying matter which provides source of nutrition. A decaying piece of fruit may have both
pathogenic bacteria and food bacteria making it essential for worms to pick and choose. One might
imagine the use of specific pattern recognition receptor or novel sensors of microbial factors in C.
elegans to prevent coming in contact with pathogenic bacteria. C. elegans is indeed capable of
avoiding some bacteria such as Pseudomonas aeruginosa. At the same time C. elegans is unable to
avoid another pathogenic bacterium Salmonella enterica. This may point to evolution of C. elegans
with P. aeruginosa in the wild. Olfactory neurons appear to play a big part in attraction to non pathogenic bacteria as well as avoidance of pathogenic bacteria.