eLife (Dec 2020)

Metabolic control of cellular immune-competency by odors in Drosophila

  • Sukanya Madhwal,
  • Mingyu Shin,
  • Ankita Kapoor,
  • Manisha Goyal,
  • Manish K Joshi,
  • Pirzada Mujeeb Ur Rehman,
  • Kavan Gor,
  • Jiwon Shim,
  • Tina Mukherjee

DOI
https://doi.org/10.7554/eLife.60376
Journal volume & issue
Vol. 9

Abstract

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Studies in different animal model systems have revealed the impact of odors on immune cells; however, any understanding on why and how odors control cellular immunity remained unclear. We find that Drosophila employ an olfactory-immune cross-talk to tune a specific cell type, the lamellocytes, from hematopoietic-progenitor cells. We show that neuronally released GABA derived upon olfactory stimulation is utilized by blood-progenitor cells as a metabolite and through its catabolism, these cells stabilize Sima/HIFα protein. Sima capacitates blood-progenitor cells with the ability to initiate lamellocyte differentiation. This systemic axis becomes relevant for larvae dwelling in wasp-infested environments where chances of infection are high. By co-opting the olfactory route, the preconditioned animals elevate their systemic GABA levels leading to the upregulation of blood-progenitor cell Sima expression. This elevates their immune-potential and primes them to respond rapidly when infected with parasitic wasps. The present work highlights the importance of the olfaction in immunity and shows how odor detection during animal development is utilized to establish a long-range axis in the control of blood-progenitor competency and immune-priming.

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