CCL2 and depressive symptom measurement: For another chemokine MCP-1, median concentrations were highest in the Abuse group (2.58 log pg/mL), followed by Depression (2.36 log pg/mL) and Abuse+Depression (2.21 log pg/mL) with mostly undetectable values for Controls (p = 0.01) (Fig 2B, Table 2B).