![Correlation of circulating platelet count with serum serotonin and serum TGF-β during bone marrow transplant. Note the logarithmic scales; Spearman’s correlation plots are displayed with linear regression line. (A) Median platelet count was significantly different between non-FA patients and patients with FA at baseline (178,000 platelets [102 000-312 000] vs 21 000 platelets [15 500-28 500]; P < .00001) and day 14 (52 000 platelets [32 000-63 500] vs 78 000 platelets [56 500-107 000]; P < .00001). (B) Serum serotonin and platelet count at baseline were significantly positively correlated in patients without FA (Spearman’s correlation coefficient, 0.75; P < .0001). (C) Serum serotonin and platelet count were also significantly positively correlated at day 14 in patients without FA (Spearman’s correlation coefficient, 0.55; P = .0031). (D-E) In patients with FA, there is no correlation between serotonin and platelet count at baseline, when platelets are host derived (Spearman’s correlation coefficient, −0.14; P = .51) (D), nor at day 14 when platelets are generally derived from the blood bank (Spearman’s correlation coefficient, 0.34; P = .12) (E). (F) Serum TGF-β increased from baseline to day 14 in patients with FA (6081.80 pg/mL [3658.49-9638.97] vs 10 745.70 pg/mL [7672.90-15 739.20]; P = .0056) but decreased in patients with other diagnoses during transplant (16 057.94 pg/mL [5804.21-20 798.64] vs 3442.77 pg/mL [2401.36-4838.18]; P = .00038). (G) Serum TGF-β and platelet count at baseline were strongly positively correlated in patients without FA (Spearman’s correlation coefficient, 0.94; P < .0001). (H) TGF-β and platelet count are also correlated at day 14 in patients without FA (Spearman’s correlation coefficient, 0.40; P = .045). (I) In contrast, serum TGF-β and circulating platelet count at baseline (host-derived platelets) show no correlation in patients with FA (Spearman’s correlation coefficient, −0.0074; P = .97). (J) At day 14 (blood bank–derived platelets), there is a strong positive correlation between serum TGF-β and platelet count in patients with FA (Spearman’s correlation coefficient, 0.83; P < .0001).](https://ash.silverchair-cdn.com/ash/content_public/journal/bloodadvances/5/1/10.1182_bloodadvances.2020002794/2/advancesadv2020002794f4.png?Expires=1725467353&Signature=21sLSdW2LXUIM8pxm97MlHhmAQLkKev9qyYKJysdfkjjw8pQBQZc2BjRkEWDzW3oH6BJLEtxMItUueCnnnQ1V6noOsXvRKI3kEMHvGCmdD6OQrpX7qd9haLzu~RoP-AvJ0j1Gn92r6M6ehn3Cuy1cgf28TumEAkCLfMXRrnSOtR45~q88zDeNo3e3hlZQVzuhDvpM-0yPFjV1kTfu9UaFDPDDWcqmnuSsCm3zFS1LJtwufXavkaOfrfsQgc0Txc4tHs4F6eqsMwZjkxfC15LHyyFlecBNwIQjEN8TA10Km~-HzW~DZJg3ErN-DBY-1~k2w5v8f8yFlkiCNHKRFYShQ__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Correlation of circulating platelet count with serum serotonin and serum TGF-β during bone marrow transplant. Note the logarithmic scales; Spearman’s correlation plots are displayed with linear regression line. (A) Median platelet count was significantly different between non-FA patients and patients with FA at baseline (178,000 platelets [102 000-312 000] vs 21 000 platelets [15 500-28 500]; P < .00001) and day 14 (52 000 platelets [32 000-63 500] vs 78 000 platelets [56 500-107 000]; P < .00001). (B) Serum serotonin and platelet count at baseline were significantly positively correlated in patients without FA (Spearman’s correlation coefficient, 0.75; P < .0001). (C) Serum serotonin and platelet count were also significantly positively correlated at day 14 in patients without FA (Spearman’s correlation coefficient, 0.55; P = .0031). (D-E) In patients with FA, there is no correlation between serotonin and platelet count at baseline, when platelets are host derived (Spearman’s correlation coefficient, −0.14; P = .51) (D), nor at day 14 when platelets are generally derived from the blood bank (Spearman’s correlation coefficient, 0.34; P = .12) (E). (F) Serum TGF-β increased from baseline to day 14 in patients with FA (6081.80 pg/mL [3658.49-9638.97] vs 10 745.70 pg/mL [7672.90-15 739.20]; P = .0056) but decreased in patients with other diagnoses during transplant (16 057.94 pg/mL [5804.21-20 798.64] vs 3442.77 pg/mL [2401.36-4838.18]; P = .00038). (G) Serum TGF-β and platelet count at baseline were strongly positively correlated in patients without FA (Spearman’s correlation coefficient, 0.94; P < .0001). (H) TGF-β and platelet count are also correlated at day 14 in patients without FA (Spearman’s correlation coefficient, 0.40; P = .045). (I) In contrast, serum TGF-β and circulating platelet count at baseline (host-derived platelets) show no correlation in patients with FA (Spearman’s correlation coefficient, −0.0074; P = .97). (J) At day 14 (blood bank–derived platelets), there is a strong positive correlation between serum TGF-β and platelet count in patients with FA (Spearman’s correlation coefficient, 0.83; P < .0001).