אירועים
אירועים והרצאות בפקולטה למדעי המחשב ע"ש הנרי ומרילין טאוב
ישי שמעוני (אונ' קולומביה, ניו יורק)
יום רביעי, 16.02.2011, 15:30
When monocyte-derived human dendritic cells (DCs) are infected by Newcastle
disease virus, the virus is known to be detected by RIG-I proteins, which
induces interferon production. Interferon activates a host of genes, including
the gene coding RIG-I. Single cell measurements is DCs show large cell to cell
variation of 3-4 orders of magnitude at 6-10 hours after infection. In order
analyze early times after infection, when reliable direct single cell data
cannot be obtained, an agent-based mathematical model was developed. The model
was correlated with biochemical time-course measurements of the levels of IFNB1
and DDX58 (RIG-I). Simulations showed that a high level of variation and the
presence at early times of a small number of early responder cells is necessary
for explaining the experimental data as well as for efficient and controlled
activation of the IFNB1-DDX58 positive feedback loop. The model generated
testable predictions that were confirmed by single cell experiments. The
results suggest that large cell-to-cell response variation plays a significant
role in the early innate immune response, and that the variability is in fact
essential to the efficient activation of the IFNB1 based feedback loop.