Dysregulated CD38 Expression on Peripheral Blood Immune Cell Subsets in SLE.

Area of Science:

• Immunology
• Cell Biology
• Rheumatology

Background:

• CD38 is a therapeutic target in systemic lupus erythematosus (SLE) due to its high expression on plasma cells.
• Investigating CD38 expression on various leukocyte subsets is crucial for understanding its therapeutic potential and biomarker utility in SLE.

Purpose of the Study:

• To analyze CD38 expression distribution across peripheral blood leukocyte lineages in SLE patients.
• To evaluate the potential therapeutic effects of CD38-targeting antibodies on specific immune cell subsets in SLE.
• To determine the utility of CD38 as a biomarker for disease activity in SLE.

Main Methods:

• Flow and mass cytometry were used to analyze CD38 expression on peripheral blood leukocyte subsets.
• Two cohorts totaling 56 SLE patients were studied.
• CD38 expression levels were correlated across immune cell lineages, subsets, and with clinical/serologic disease parameters.

Main Results:

• CD38 expression was significantly increased in SLE patients compared to healthy controls on plasmacytoid dendritic cells, monocytes, natural killer cells, B cells, and T cells.
• Coordinated CD38 expression was observed between innate and memory T cell subsets in SLE patients, but not in healthy controls.
• CD38 expression was heterogeneous across SLE patients and did not correlate with disease activity scores (SLEDAI-2K) or serologic markers.

Conclusions:

• Widespread changes in CD38 expression occur on SLE immune cells, with coordinated expression within individuals but heterogeneity across the patient population.
• CD38 expression levels did not correlate with SLE disease severity or clinical manifestations.
• These findings have implications for personalized anti-CD38 monoclonal antibody therapy in SLE, guiding the targeting of pathogenic leukocytes.