Elevated Serum IL-2 Levels are Associated With Major Depressive Disorder: A Case-Control Study

Area of Science:

• Neuroscience
• Immunology
• Psychiatry

Background:

• Major depressive disorder (MDD) is associated with inflammation.
• The role of specific cytokines, like IL-2, in MDD pathophysiology requires clarification.

Purpose of the Study:

• To investigate the association between serum levels of the pro-inflammatory cytokine IL-2 and MDD.
• To determine if IL-2 levels differ between MDD patients and healthy controls.
• To explore the potential of IL-2 as a biomarker for MDD.

Main Methods:

• Blood samples were collected from 111 MDD patients and 112 healthy controls.
• Depression severity was assessed using the Hamilton Depression (Ham-D) rating scale.
• Serum IL-2 levels were quantified using Enzyme-Linked Immunosorbent Assay (ELISA).

Main Results:

• MDD patients exhibited significantly higher serum IL-2 levels compared to healthy controls.
• Elevated IL-2 levels were particularly noted in female MDD patients.
• A positive correlation was observed between serum IL-2 levels and Ham-D scores in females, with IL-2 showing good diagnostic performance as a biomarker.

Conclusions:

• Elevated serum IL-2 is associated with MDD, suggesting a potential role in the disorder's development or progression.
• Further interventional studies are recommended to elucidate the causal relationship between IL-2 and MDD.
• Serum IL-2 may serve as a valuable biomarker for MDD.