N642H^vav/+ mice develop a hematopoietic malignancy. (A) Schematic overview of the generation of N642H^vav/+ mice. (B) V5, pYSTAT5, and STAT5A/B immunoblot analysis of BM cells from vav-N642H (n = 1), N642H^vav/+ (n = 4), and control (N642H^STOP/+) mice (n = 4) (left). α-TUBULIN served as loading control. Quantification of fold change (fc) of pYSTAT5 relative to total STAT5A/B levels, based on immunoblot analysis, from 8-week-old control and N642H^vav/+ BM cells (n = 4 per genotype; mean ± standard deviation [SD]) (right). (C) Relative quantification of spleen weights from 8-week-old control and N642H^vav/+ mice (n = 4 per genotype; mean ± SD). (D) Relative quantification (percentages out of living cells) (left) and total numbers (right) of myeloid cells (CD11b⁺Gr1⁺), B cells (CD19⁺), CD4⁺ T cells (CD3⁺CD4⁺), CD8⁺ T cells (CD3⁺CD8⁺), and NK cells (CD3^–NK1.1⁺) in the spleen of 8-week-old control and N642H^vav/+ mice (n = 4 per genotype; mean ± SD). (E) Survival analysis of aged N642H^vav/+ (142-363 days of survival) and control mice (n ≥ 5 per genotype). (F) Representative pictures of spleens and LNs of aged control (left) and diseased N642H^vav/+ mice (right). (G) Relative quantification (left) and total numbers (right) of myeloid cells (CD11b⁺Gr1⁺), B cells (CD19⁺), CD4⁺ T cells (CD3⁺CD4⁺), CD8⁺ T cells (CD3⁺CD8⁺), and NK cells (CD3^-NK1.1⁺) in the spleen of aged control (∼360 days old) and diseased N642H^vav/+ mice (end point analysis; n ≥ 5 per genotype; mean ± SD). (H) Hemacolor Rapid staining of blood smears from control and diseased N642H^vav/+ mice (1 representative picture per genotype). (I) Hematoxylin and eosin staining of lung tissue from control and diseased N642H^vav/+ mice (1 representative picture per genotype). Levels of significance were calculated using the unpaired t test (B-D and G) and the Mantel-Cox test (E). ∗P < .05; ∗∗P < .01; ∗∗∗P < .001; ∗∗∗∗P < .0001. LNs, lymph nodes.