2.7 Immunofluorescence assay
The colon and spleen tissue slices were blocked with goat serum for 30
min in each group. The goat serum was discarded, and the sample was
washed twice with PBS and wiped with water-absorbing paper. 50 µL of
diluted antibody (1:500) was added to the sample, and PBS was added to
the negative control group instead. After washing 3 times, fluorescent
secondary (1:2000) was added, and the sample was incubated in the dark
at room temperature for 2 hours. Washing twice with PBS, adding an
antiquenching agent dropwise, the sample was observed, and images were
acquired under a fluorescence microscope.