Figure 2. Preferential localization of B cells in the splenic MZ upon inducible B cell–specific deletion of irf4. irf4fl/flCD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and CD20-TAM-Cre mice were injected with three doses of TAM on three consecutive days and analyzed 11–14 d after the last injection. Images show one representative mouse per group (irf4fl/flCD20-TAM-Cre: n = 6; irf4fl/+CD20-TAM-Cre: n = 8; CD20-TAM-Cre: n = 4; four independent experiments), except for C. (A) CD21 and CD23 expression by CD19+ splenic B cells from CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice were analyzed by flow cytometry. Numbers above gates indicate the percentage of CD23+CD21int FO and CD23−CD21hi MZ B cells. (right) eGFP expression by splenic FO and MZ B cells from CD20-TAM-Cre (green lines), irf4fl/+CD20-TAM-Cre (blue lines), and irf4fl/flCD20-TAM-Cre (red lines) mice was assessed by flow cytometry. (B) Spleen sections from CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice were stained with H&E or analyzed for expression of eGFP counterstained with hematoxylin or with anti-IgM. Boxes demarcate the area shown at higher magnification to the right. (C) Ratio between the MZ and the lymphoid follicle areas in the spleen of CD20-TAM-Cre (+/+), irf4fl/+CD20-TAM-Cre (fl/+), and irf4fl/flCD20-TAM-Cre (fl/fl) mice was calculated using the ImageJ software on three mice of each genotype from three independent experiments (+/+: 24 follicles; fl/+: 33 follicles; fl/fl: 25 follicles). Data are shown as mean ± SD. Statistical significance was determined by Student’s t test (**, P < 0.01). (D) IgM expression in splenic sections of CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice was assessed by IHC. Boxes demarcate the area shown at higher magnification below. (B and D) Dashed lines demarcate the border between the FO and MZ areas. (E) IgD and IgM expression in the spleen of CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice was analyzed by IHC. Dashed lines mark the inner and outer border of the MZ area. Bars: (B [left] and D [top]) 500 µm; (B, right) 125 µm; (D [bottom] and E) 100 µm.
Figure 2.

Preferential localization of B cells in the splenic MZ upon inducible B cell–specific deletion of irf4. irf4fl/flCD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and CD20-TAM-Cre mice were injected with three doses of TAM on three consecutive days and analyzed 11–14 d after the last injection. Images show one representative mouse per group (irf4fl/flCD20-TAM-Cre: n = 6; irf4fl/+CD20-TAM-Cre: n = 8; CD20-TAM-Cre: n = 4; four independent experiments), except for C. (A) CD21 and CD23 expression by CD19+ splenic B cells from CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice were analyzed by flow cytometry. Numbers above gates indicate the percentage of CD23+CD21int FO and CD23−CD21hi MZ B cells. (right) eGFP expression by splenic FO and MZ B cells from CD20-TAM-Cre (green lines), irf4fl/+CD20-TAM-Cre (blue lines), and irf4fl/flCD20-TAM-Cre (red lines) mice was assessed by flow cytometry. (B) Spleen sections from CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice were stained with H&E or analyzed for expression of eGFP counterstained with hematoxylin or with anti-IgM. Boxes demarcate the area shown at higher magnification to the right. (C) Ratio between the MZ and the lymphoid follicle areas in the spleen of CD20-TAM-Cre (+/+), irf4fl/+CD20-TAM-Cre (fl/+), and irf4fl/flCD20-TAM-Cre (fl/fl) mice was calculated using the ImageJ software on three mice of each genotype from three independent experiments (+/+: 24 follicles; fl/+: 33 follicles; fl/fl: 25 follicles). Data are shown as mean ± SD. Statistical significance was determined by Student’s t test (**, P < 0.01). (D) IgM expression in splenic sections of CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice was assessed by IHC. Boxes demarcate the area shown at higher magnification below. (B and D) Dashed lines demarcate the border between the FO and MZ areas. (E) IgD and IgM expression in the spleen of CD20-TAM-Cre, irf4fl/+CD20-TAM-Cre, and irf4fl/flCD20-TAM-Cre mice was analyzed by IHC. Dashed lines mark the inner and outer border of the MZ area. Bars: (B [left] and D [top]) 500 µm; (B, right) 125 µm; (D [bottom] and E) 100 µm.

This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal