Histology
At 3 days after CLP challenge[21], mice were sacrificed by
CO2 inhalation. Then, the spleens were collected and
fixed in 4% paraformaldehyde solution for more than 48 hours before
being embedded in paraffin and sectioned. After deparaffinization and
rehydration, the sections were stained with hematoxylin and eosin
(H&E). The congestion and necrosis of the spleen tissue and the
aggregation of inflammatory cells were evaluated under an optical
microscope. Then the spleen injury scores of mice based on the results
of H&E[23] was evaluated by two independent, blinded researchers.