WT and SPARC-deficient mice die of hematopoietic failure in response to serial 5-FU treatment. (A) Hematoxylin and eosin stainings of bone and gut sections of WT and Sparc^−/− mice dying from serial 5-FU treatment (age at start of treatment, 8 weeks; age at examination, 14 and 16 weeks for WT and Sparc^−/− mice, respectively). Trabecular and central bone regions are aplastic, suggesting WT and Sparc^−/− mice die of hematopoietic failure. Examples for aplastic BM regions are indicated with arrowheads. In contrast, the intestinal architecture is still intact in WT and Sparc^−/− mice. (B) BM counts of untreated and WT and Sparc^−/− mice dying from serial 5-FU treatment indicate that all mice dying from serial 5-FU treatment show severe aplastic anemia. (C) WBC counts of untreated and WT and Sparc^−/− mice dying from serial 5-FU treatment. All mice dying from serial 5-FU treatment show severe leukopenia. (D) RBC counts of untreated and WT and Sparc^−/− mice dying from serial 5-FU treatment. All mice dying from serial 5-FU treatment show severe anemia. (E) Platelet counts of untreated and WT and Sparc^−/− mice dying from serial 5-FU treatment. All mice dying from serial 5-FU treatment show severe thrombocytopenia. Each data point represents an individual mouse. N = 6-7 per group; mean; ****P < .001; unpaired 2-tailed Student t test).