Figure 1.

Histological analysis and incidence of T cells in small intestines (jejunum) of BALB/c and DO11.10 mice after treatments with OVA. Mice were fed with OVA solution for 7 days (oral OVA), fed with OVA and challenged by ip route (oral + ip OVA), immunized with OVA only by ip route (ip OVA), or non-treated (control). (a) Hematoxylin/Eosin-stained sections of small intestines in low and high magnification showing details of mucosa villi. Note the reduced thickness of the tunica muscular (arrow heads) in DO11.10 when compared with BALB/c, and loss of connective tissue and mild edema in the lamina propria (thin arrows) in Oral + ip OVA and ip OVA groups of DO11.10 mice. Bars = 50 μm. (b) Immunofluorescence of frozen sections of jejunum counterstained with TRITC-phalloidin (red epithelial cells) showing reduced incidence of CD3 positive cells (green) in the mucosa of DO11.10 in comparison to BALB/c mice. Bars = 25 μm; (c, d) Frequency of KJ1-26 positive cells amongst the intraepithelial lymphocytes freshly isolated from DO11.10 mice treated with OVA. The clonotype anti-OVA TCR cells (KJ1-26⁺ cells) decreased from 65% to less than 20% after oral and ip administration of OVA. Data represent mean ± SEM (N = 5) of three independent experiments.