Figure 7.

Transgenic Bcl2 Causes Uncontrolled Expansion of Pten-Deficient B Cells

(A) Macroscopic appearance of spleens from Pten^f/f × CD19-cre, Pten^f/f × Bcl2^tg, and Pten^f/f × CD19-cre × Bcl2^tg mice sacrificed at the age of 10 weeks.

(B) Absolute numbers of CD19⁺ and B-1a B cells in Pten^f/f x CD19-cre x Bcl2^tg (n = 5) and Pten^f/f x Bcl2^tg (n = 5) compared to the Pten^f/f x CD19-cre and control mice already shown in Figures 1C and 5F (median ± quartile and range).

(C and D) Cells freshly isolated from spleens (C) and bone marrow (D) of Pten^f/f × CD19-cre, Pten^f/f × Bcl2^tg, and Pten^f/f × CD19-cre × Bcl2^tg mice were analyzed by flow cytometry for surface expression of the indicated markers. Representative data are shown from at least 5 mice sacrificed and analyzed at the age of 10 weeks.

(E) ELISpot assay for secretion of IgM and IgG, respectively. IgM^−/lo/IgD⁻ splenic B cells derived from mice of the indicated genotypes were FACS-purified and their capacity to secrete antibody was analyzed in triplicate after 16–24 hr of incubation (top). Numbers of dots in the triplicates were quantified (bottom), mean ± SD.

(F) IgM levels measured in sera from Pten^f/f × CD19-cre × Bcl2^tg (n = 9), Pten^f/f × Bcl2^tg (n = 7), Pten^f/f × CD19-cre (n = 5), and control mice (n = 3) (mean ± SD).

(G) Splenocytes from Pten^f/f × CD19-cre, Pten^f/f × Bcl2^tg, and Pten^f/f × CD19-cre × Bcl2^tg mice were analyzed by flow cytometry for surface expression of CD138 and B220 in the BCR⁺ (CD19⁺/B220⁺/IgM⁺/IgD⁺) and BCR^−/lo (CD19⁺/B220⁺/IgM^−/lo/IgD⁻) population of B cells.

See also Figure S7.