Fig. 1. Erythroid lineage-specific TFPI knockout results in erythropoietic impairment in mice.

A TFPI and TF concentrations in the plasma of healthy controls and JAK2V617^F mutation polycythemia (Healthy, n = 18; JAK2^V617F, n = 21). B Protocol used for human EBI formation. C Representative cytospin images of EBIs formed between erythroblasts and macrophages with JAK2^V617F mutation (n = 3). Scale bars, 10 μm. D TFPI and TF mRNA expression in erythroblasts or macrophages with JAK2^V617F mutation (n = 5). E TFPI mRNA expression in erythroblasts cultured with or without macrophages. Alone, erythroblasts culture independently; co-culture, erythroblasts co-culture with macrophages (n = 5). F TFPI mRNA and protein expression in F4/80⁺CD169⁺Vcam-1⁺ macrophages (CM) and Ter119⁺ cells (RT-qPCR, n = 5; Western blot, n = 3). G Protocol used to prepare TFPI^f/f;EpoR mice. H PB RBC numbers, Hb, and HCT in TFPI^f/f;EpoR mice (n = 5). I Frequency of erythroblast populations among BM cells in TFPI^f/f;EpoR mice (n = 5). J Frequency of apoptotic erythroblasts among BM cells in TFPI^f/f;EpoR mice (n = 5). K CFU-E number in TFPI^f/f;EpoR mice (n = 5). L EBI (F4/80⁺Ter119⁺ live multiplets) numbers in the BM of TFPI^f/f;EpoR mice. (n = 5). M EBI numbers in the spleen of TFPI^f/f;EpoR mice (n = 5). N PB RBC numbers, Hb, and HCT in Jak2^V617F-mutated, TFPI^f/f;Vav, or Jak2^V617F;TFPI^f/f;Vav mice (n = 5). O Frequency of RIII and RIV erythroblast populations among BM cells in Jak2^V617F-mutated, TFPI^f/f;Vav, or Jak2^V617F; TFPI^f/f;Vav mice (n = 5). Statistical analysis was performed using one-way ANOVA (A, D, F, H–I, J-K and L–O). Data are shown as mean ± SEM and are representative of two (C, H–I, and L–O) or three (A, D–F, and J, K) independent experiments. Source data are provided as a Source Data file.