Figure 4. Localization of polymeric immunoglobulin receptor (pIgR) protein in three sites of the gastric mucosa of a representative pig aged 42 days.

PIgR protein immunostaining in a 42 day-old representative piglet, in the transition from cardiac to oxyntic mucosa (A), in the proper glandular region (oxyntic mucosa) (B) and in the pyloric region (C). Negative control is with the omission of primary antibody (D). Bar indicates 200 µm (50× magnification).