Table 1

Stat5a and Stat5b both restore myeloproliferation when coexpressed with TEL-PDGFRB in Stat5a-deficient bone marrow cells

ConstructPhenotypeMedian survival, dPn
TPiGFP into Stat5a+/+Fatal MPD: 631 ± 2.615
TPiGFP into Stat5a+/−Fatal MPD: 2; MPD: 5145 ± 16.0< .00119
TPiGFP into Stat5a−/−Fatal MPD: 1; MPD: 8144 ± 4.1< .00117
TPiStat5a add-back into Stat5a+/−Fatal MPD: 128 ± 9.0.7326
TPiStat5a add-back into Stat5a−/−Fatal MPD: 6; MPD: 296 ± 35.5< .00112
TPiStat5b add-back into Stat5a−/−MPD: 297 ± 7.5< .0018
  • Median survival of mice in each cohort is shown with standard error. Disease phenotype at time of death was characterized as either fatal MPD (WBC, > 50 × 109/L [50 000/μL] and spleen weight, > 450 mg) or MPD (WBC, > 15 × 109/L [15 000/μL] and/or spleen weight, > 450 mg) with number of analyzed mice indicated. Statistical significance in survival between TPiGFPStat5+/+ and each cohort is shown by P value (determined by Mantel-Cox log rank). Statistical significance in survival between cohorts is determined by log rank (Mantel-Cox) such that the difference in survival of TPiGFPStat5a−/− and TPiStat5bStat5a−/− has a P value of .01 and the difference in TPiStat5aStat5a−/− and TPiStat5bStat5a−/− cohort survival has a P value of .79. TPiStat5aStat5a+/− mice developed severe MPD (spleen weight, 520 mg [n = 1]; WBC, 66 × 109/L [66 000/μL] [n = 1]). Moderate MPD was detected in TPiStat5aStat5a−/− mice (spleen weight median, 800 ± 170 mg; range, 550-970 mg [n = 8]; WBC median, 82 ± 106 × 109/L [82 000 ± 106 000/μL]; range, 40-108 × 109/L [40 000-108 000/μL] [n = 7]) and TPiStat5bStat5a−/− mice (spleen weight median, 470 ± 184 mg; range, 340-600 mg [n = 2]; WBC median, 23 ± 10 × 109/L [23 000 ± 10 000/μL]; range, 16-30 × 109/L [16 000-30 000/μL] [n = 2]). TPiGFP indicates TEL-PDGFRB ires eGFP; TPiStat5a, TEL-PDGFRB ires mStat5a; TPiStat5b, TEL-PDGFRB ires Stat5b; MPD, myeloproliferative disease; and WBC, peripheral white blood cell count; and —, not applicable.