Immunohistochemical analysis of spleens at day 10 after immunization with SRBCs. (A) Representative hematoxylin and eosin (H&E), HGAL, PAX5, B220, and PNA staining of serial sections of spleens from Rosa26^HGAL/Aid-Cre, Rosa26^HGAL/Sca1-Cre, Rosa26^HGAL, Rosa26^HGAL/Mb1-Cre, and WT mice. HGAL is strongly expressed in the GC lymphocytes of Rosa26^HGAL/Aid-Cre and Rosa26^HGAL/Sca1-Cre animals, with weaker expression in Rosa26^HGAL/Mb1-Cre animals because of the smaller size of GCs. (B) Quantification of the number (left panel) and area (right panel) of PNA-stained GC centers in Rosa26^HGAL/Aid-Cre, Rosa26^HGAL/Sca1-Cre, Rosa26^HGAL, Rosa26^HGAL/Mb1-Cre, and wild type-mice (n = 6 each). Data are mean ± standard deviation. *P < .05; **P < .01; ***P < .001, Bonferroni multiple-comparison test (1-way analysis of variance).