IL17A and escherichia coli infection: The effect of GM on gut mucosal immunity is first reflected in promoting the development of the host immune system (Fiedler et al., 2013)..GM induces gut type 3 Innate lymphoid cells(ILCs) to produce Interleukin-17(IL-17), increasing plasma Granulocyte Colony-Stimulating Factor (G-CSF) levels and neutrophil numbers in a Toll-like receptor 4 (TLR4) and myeloid differentiation factor 88 (MyD88)-dependent manner,which is essential for combating E. coli sepsis in neonatal mice (Deshmukh et al., 2014).