Elevated transferrin receptor 1 promoting B-cell autoimmunity in systemic lupus erythematosus

Area of Science:

• Immunology
• Autoimmunity
• Molecular Biology

Background:

• Transferrin receptor 1 (TFR1) is a key iron receptor on immune cells.
• TFR1 may negatively impact T cell metabolism and function in systemic lupus erythematosus (SLE).
• This study investigates TFR1's role and mechanisms in lupus B cells.

Purpose of the Study:

• To examine the effects of TFR1 on B cells in lupus.
• To elucidate the mechanisms by which TFR1 influences lupus B cell function.
• To explore the relationship between TFR1, toll-like receptor 7 (TLR7), and SLE pathogenesis.

Main Methods:

• Flow cytometry (FCM) was used to analyze TFR1, iron, reactive oxygen species (ROS), and lipid peroxidation in B cells from lupus models and patients.
• Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) assessed TFR1 transcript levels.
• In vitro gene silencing identified upstream regulatory molecules.

Main Results:

• Toll-like receptor 7 (TLR7) agonist R848 increased TFR1 expression in B cells from certain lupus mouse models.
• Anti-TFR1 antibody treatment reduced iron deposition, ROS, lipid peroxidation, and autoantibody production in lupus B cells.
• TFR1 was highly expressed in SLE patient B cells, correlating with TLR7, disease activity, iron deposition, and ROS production.

Conclusions:

• TLR7-regulated TFR1 drives B-cell autoimmunity by increasing ROS production.
• TFR1 plays a significant role in the pathogenesis of systemic lupus erythematosus (SLE).
• Targeting TFR1 may offer a therapeutic strategy for SLE.