Exploring macrophage cell therapy on Diabetic Kidney Disease

Area of Science:

• Immunology
• Nephrology
• Regenerative Medicine

Background:

• Alternatively activated macrophages (M2) possess regenerative capabilities, making them promising for cell therapy in chronic kidney disease (CKD).
• Macrophage plasticity, particularly maintaining the M2 phenotype, presents a significant challenge for therapeutic applications.
• Neutrophil gelatinase-associated lipocalin (NGAL) can stabilize the M2 macrophage phenotype, as shown in previous studies.

Purpose of the Study:

• To investigate the therapeutic efficacy of bone marrow-derived M2 (BM-M2) macrophages and NGAL-modified macrophages (NGAL-M2) in a mouse model of diabetic kidney disease (DKD).
• To assess the impact of these cell therapies on key indicators of kidney damage and inflammation in the context of diabetes.

Main Methods:

• Seventeen-week-old db/db mice with established DKD were allocated into five treatment groups: D+BM-M2, D+NGAL-M2, and controls.
• Macrophages (1 × 10^6) were infused twice, at baseline and two weeks later.
• Therapeutic effects were evaluated by measuring albuminuria, renal fibrosis, inflammatory cytokine profiles, M1 macrophage proportion, podocyte loss, and TGF-β1 levels.

Main Results:

• Bone marrow-derived M2 (BM-M2) macrophages did not demonstrate significant therapeutic effects.
• NGAL-modified macrophages (NGAL-M2) significantly reduced albuminuria and renal fibrosis.
• NGAL-M2 therapy increased anti-inflammatory IL-10, decreased pro-inflammatory cytokines, reduced M1 glomerular macrophages and podocyte loss, and lowered renal TGF-β1.

Conclusions:

• NGAL-modified macrophage cell therapy exhibits significant therapeutic effects in a mouse model of DKD.
• The therapy likely functions by modulating the renal inflammatory response within the diabetic environment.
• This approach holds promise for treating DKD by stabilizing M2 macrophages and mitigating kidney damage.