Serum ALCAM is a potential novel non-invasive marker for predicting the progression of IgA nephropathy.

BACKGROUND: Activated leukocyte cell adhesion molecule (ALCAM) serves as an important effector that activates and traffics lymphocytes into tissues. The expression and role of ALCAM in IgA nephropathy (IgAN) remain unclear. Here, we aim to evaluate the expression and effect of ALCAM in IgAN patients. METHODS: We performed a prospective study including 71 IgAN patients, and 41 controls. Serum and uALCAM levels were evaluated. Renal expression of ALCAM and its ligand S100B were measured. The correlation of serum ALCAM with clinical data, renal pathology, and prognosis was analyzed. Cox regression analysis was conducted to identify independent factors associated with prognosis. Kaplan-Meier survival analysis was performed to explore the role of serum ALCAM. RESULTS: Circulating ALCAM levels were higher in IgAN patients than in controls. Serum ALCAM levels showed a positive correlation with proteinuria and renal pathology. Renal ALCAM expression was also elevated in IgAN patients. IgAN patients were divided into low and high ALCAM groups (< 4.76, and ≥ 4.76 ng/mL) based on the optimal cut-off value for predicting renal progression. The high ALCAM group exhibited more severe clinical parameters and renal pathology. High serum ALCAM level was an independent risk factor for IgAN progression. IgAN patients with high ALCAM level exhibited a lower cumulative renal survival rate compared to the low-level group. CONCLUSIONS: In summary, serum ALCAM level in IgAN patients was elevated, which was consistent with clinical and pathological severity, and served as an independent risk factor and a promising novel predictor for the progression of IgAN. CLINICAL TRIAL NUMBER: Not applicable.