Xenotransplantation of MDS cells in NSG mice. (A-B) Immunophenotypic profiling of human cells in NSG mice. Shown are percentages of hCD45⁺, myeloid (CD14⁺ or CD15⁺), and B lymphoid (CD19⁺) cells in the hCD45⁺ cell fraction, at 5 to 15 weeks posttransplantation. (C-G) Genotype of sorted MDS CD14⁺CD15⁺, CD19⁺, or CD34⁺ populations after xenografting. Shown are VAFs and the 95% CIs of each mutation in BM MNCs, PDX CD14⁺CD15⁺, PDX CD19⁺, and PDX CD34⁺. In UPNs 2, 10, and 12, mutations were screened by NGS. For UPN 8, mutations in PDX CD14⁺CD15⁺ and CD19⁺ populations were detected by Sanger sequencing on amplified whole genome DNA. (D) For UPN 2, hypotheses regarding the contribution of CD34⁺-mutated clones to their myeloid CD14⁺CD15⁺ (My) and lymphoid CD19⁺ (Ly) progenies are schematically depicted. Each mutation is represented by its initial. A color spectrum is used for the different intervals of variant allele frequencies.