Axio imager m2

For frozen sections, intestinal tissues were washed with
phosphate-buffered saline (PBS) and fixed with 4% paraformaldehyde (PFA) at
4°C, followed by consecutive 15% and 30% sucrose immersion before
freezing in Optimal Cutting Temperature (O.C.T.) compound (Sakura Finetek,
Torrance, CA). Cryosections were mounted onto glass slides and incubated at room
temperature for 30 minutes in PBS containing 0.1% Triton 100-X (PBST) and 2.5%
normal donkey serum to reduce non-specific immunostaining. Alternatively for
human samples, Protein Block Serum-Free (DAKO, Carpinteria, CA) was used to
reduce non-specific immunostaining. The sections were incubated with primary
antibody at room temperature for one hour. Sections were then washed three times
in PBS, and incubated with secondary antibodies for 30 minutes at room
temperature. Sections were counterstained with 4',6-diamidino-2-phenylindole
(DAPI) for nuclear detection. Primary and secondary antibodies used are listed
in Supplementary Table(Antibody list). Micrographic images were obtained using an Olympus IX-71
(Olympus, Center Valley, PA) for mouse tissue, and Axio Imager.M2 (Zeiss,
Thornwood, NY) for human tissue (Figure 2Eupper row). Images presented are representatives of 3 mouse or human
samples.