Multiple transcripts associated with the myeloid lineage of immune cells were also upregulated, including CD36, LY6E and the macrophage-associated TF MAFB. However, transcripts associated with macrophage activation also numbered among the downregulated transcripts, including several that were upregulated in leukocytes from MDD versus control subjects at baseline (for example, APOBEC3B*, ARG1*, IL-1R1, MMP8, PI3* and XIST*). Here, PI3 is linked to major depressive disorder.