Assessing the Role of CD103 in Immunity to an Intestinal Helminth Parasite

Background: In the intestine, the integrin CD103 is expressed on a subset of T regulatory (T(reg)) cells and a population of dendritic cells (DCs) that produce retinoic acid and promote immune homeostasis. However, the role of CD103 during intestinal helminth infection has not been tested. Methodology/Principal Findings: We demonstrate that CD103 is dispensable for the development of protective immunity to the helminth parasite Trichuris muris. While we observed an increase in the frequency of CD103(+) DCs in the lamina propria (LP) following acute high-dose infection with Trichuris, lack of CD103 had no effect on the frequency of CD11c(+) DCs in the LP or mesenteric lymph nodes (mLN). CD103-deficient (CD103(-/-)) mice develop a slightly increased and earlier T cell response but resolve infection with similar kinetics to control mice. Similarly, low-dose chronic infection of CD103(-/-) mice with Trichuris resulted in no significant difference in immunity or parasite burden. Absence of CD103 also had no effect on the frequency of CD4(+) CD25(+) Foxp3(+) Treg cells in the mLN or LP. Conclusions/Significance: These results suggest that CD103 is dispensable for intestinal immunity during helminth infection. Furthermore, lack of CD103 had no effect on DC or Treg recruitment or retention within the large intestine.