Plasma cell survival intermediary identified
doi:10.1038/nindia.2014.33 Published online 12 March 2014
Researchers have identified inducible nitric oxide synthase (iNOS) as a key intermediate that supports the survival of plasma cells, the workhorses of immunological protection in mammals1 . They have also shown that iNOS deficiency results in a shorter lifespan for plasma cells.
Biologists from National Institute of Immunology, New Delhi further reported that iNOS deficiency did not have any effect on the activation and terminal differentiation of B cells.
While a number of extrinsic factors have known to promote the survival of plasma cells, the signaling intermediates involved had not been studied properly till now.
The researchers showed in vitro that plasma cells which were deficient in iNOS died more. The protection mediated by iNOS involved activation of protein kinase G and modulation of endoplasmic reticulum stress components, they report. Activation of caspases was also diminished.
"We found that iNOS was required for PCs to respond to some prosurvival mediators associated with bone marrow stromal cells and that at least one mediator, interleukin 6, fed directly into this pathway by inducing iNOS," the researchers report.