Neonatal Fc receptor for IgG regulates mucosal immune responses to luminal bacteria
J. Clin. Invest. Masaru Yoshida, et al. 116:2142 doi:10.1172/JCI27821 [Go to this article.]

Figure 1
Absence of intestinal luminal IgG in FcRn^–/– mice. (A) The construct for the Tg IFABP-mFcRnTg/mβ2mTg mouse, designed to express mFcRn and mβ2m under the control of the IFABP. (B) Increased mFcRn expression in epithelial cells of IFABP-mFcRnTg/mβ2mTg (Tg) mouse. RNA was extracted from epithelial cells of upper and lower small intestines (USI and LSI, respectively) and cecum in 6-week-old IFABP-mFcRnTg/mβ2mTg founder BALB/c mice and littermate WT BALB/c mice and subjected to RT-PCR. (C and D) Immunohistochemical analysis of lower small intestine in WT (C) and IFABP-mFcRnTg/mβ2mTg mice (D). Arrows indicate staining of FcRn. (E–H) The levels of Igs secreted into the intestinal lumen. Secretory IgM (E), dimeric IgA (F), IgG1 (G), and IgG2a (H) were measured by ELISA. The mean ± SD are shown for each group (n = 8). *P < 0.05. (I) The levels of Igs (IgG1, IgG2a, IgG2b, IgG3, IgA, IgM, and IgE) secreted into the lumen of the indicated mouse strains on a C57BL/6 background were measured by a cytometric bead array.