Mucin hypersecretion is considered to be one of the most common components of the immune response to gastrointestinal
nematode infection. However, investigations have not been conducted in the Cattle-Cooperia oncophora system to verify the findings largely derived from murine models. In this study, we examined the expression of seven
mucins and seven
enzymes in the
mucin biosynthesis pathway involved in O-linked glycosylation in the bovine small intestine including goblet cells enriched using
laser capture microdissection during a primary C. oncophora
infection. At the
mRNA level, MUC2 expression was significantly higher in both lamina propria and goblet cells at 28 days post-
infection compared to the naive control. MUC5B expression at the
mRNA level was also higher in lamina propria at 28dpi. Expression of MUC1, MUC4, MUC5AC, and MUC6 was extremely low or not detectable in goblet cells, columnar epithelial cells, and lamina propria from both naive control and infected animals. Among the seven
enzymes involved in post-translational O-linked glycosylation of
mucins, GCNT3, which may represent one of the key rate-limiting steps in
mucin biosynthesis, was up-regulated in goblet cells, columnar epithelial cells, lamina propria, and gross small intestine tissue during the course of
infection. Western blot analysis revealed that MUC2
glycoprotein was strongly induced by
infection in both gross small intestine tissue and its mucosal layer. In contrast, the higher MUC5B
protein expression was observed only in the mucosal layer. Immunohistochemistry provided further evidence of the
mucin glycoprotein production and localization. Our results provided insight into regulation of
mucin biosynthesis in various cell types in the bovine small intestine during gastrointestinal
nematode infection and will facilitate our understanding of
mucins and their role in immune response against parasitic nematodes.