Fig. 4

Transcriptome profiling analysis of isolated E- and M-MDSC phenotypes. The top 20 KEGG pathways for 533 differentially expressed genes between pre-ASCT E- and M-MDSC populations (a) and for 65 differentially expressed genes between post-ASCT E- and M-MDSC phenotypic populations (b), using a threshold of a 2-fold change and P-value < 0.05. The most remarkable difference was osteoclast differentiation in pre-ASCT M- versus E-MDSCs, which was not observed in post-ASCT M- versus E-MDSC phenotypes. Among the genes associated with osteoclast differentiation, CSF1R was the most significant (c) and was confirmed using qRT-PCR in isolated peri-ASCT E- and M-MDSC phenotypes (d). The data are presented as the mean ± SEM. *P < 0.05. Next, M-CSF and IL-34, which are known to trigger CSF-1R signalling in patient sera (n = 75 for M-CSF, n = 82 for IL-34), were measured, and the correlation between these factors and the frequency of pre-ASCT (e) and post-ASCT (f) MDSC phenotypes was analysed. The Spearman correlation coefficient was used to evaluate association for continuous variables. The label of post-ASCT MDSCs on the figure means the cells expressing each MDSC phenotype