Figure legends.
Figure 1. Innate lymphoid cells. A. ILC can be divided into three
subsets ILC1, ILC2 and ILC3. ILC1 express the transcription factor T-bet
and, in response to IL-12, IL-15, and IL-18, produce IFN-γ and TNF-α.
ILC2 express the transcription factor GATA-3 and, in response to the
alarmins TSLP, IL-25, HMGB1 and IL-33, secrete IL-4, IL-5 and IL-13.
ILC3 express the transcription factor RORγt and in response to IL-23 and
IL-1β, release IL-17 and IL-22. B. ILC2 can transdifferentiate into ILC1
or ILC3 in response to IL-1β IL-12 and TGF-β and these trans
differentiations can be reversed by Th2 cytokines, as IL-4. C.
Toll-like-receptor-2 ligands can promote the production of the Th2
cytokines IL-5 and IL-13 by ILC3 cells, which suggests that these cells
might be able to differentiate into ILC2 cells.
Figure 2. Following RSV infection, through the release alarmins
BECs stimulate ILC2 to release IL-4, IL-5, and IL-13. IL-4 drives Th2
cell differentiation and promotes B cell antibody class switch to IgE.
IL-5 is involved in eosinophils recruitment and in their survival
enhancement. IL-13 increases goblet cell mucin and airway
responsiveness.
Figure 3. Changes in gut microbiota community composition
following RSV infection and allergen sensitization in mice. A. RSV
infection was associated with significant increase in the relative
abundance of Bacteroidetes and a corresponding decrease
in Firmicutes . B. In ovalbumin (OVA) sensitized mice, lower
abundance of both Bacteroidetes and Firmicutes infection
was detected. C. in mice, previously sensitized to OVA, RSV infection
was associated with higher abundance of both Bacteroidetes andFirmicutes . Bacteroidetes were most significantly
associated with IL-4, IL-5, IL-13, IL-25, and IL-33 production andFirmicutes with IL-33.