Impact of Mannose-Binding Lectin (MBL) on Graft Survival in Transplant Recipients with IgAN

Background: The progression of IgAN has been linked to functional defects and serum levels of MBL.Specific SNPs in the promoter and exon1 of the MBL2 gene are associated with these qualitative/quantitative deficiencies.Given that deregulation of the lectin pathway may impact IgAN progression in native kidneys, we evaluated whether MBL2 SNPs and MBL levels affect graft survival in kidney transplant recipients with IgAN. Methods: We enrolled 60 kidney transplant patients diagnosed with IgAN in the native kidney.The MBL2 variants (promoter: L/H, Y/X, P/Q alleles and exon1: A/O allele) were analyzed by Sanger sequencing.MBL levels were measured using ELISA kit. Clinical data at baseline and during the follow-up were collected. An eGFR <60mL/min/1.73m2 (CKD-EPI) was considered the primary outcome in univariate and multivariate analyses. Results: No significant impact of MBL2 genotype and serum levels on demographic features, donor variables, transplant-related variables, recurrence, and DGF was found.However, patients with the “O” allele exhibited higher creatinine values at the time of graft biopsy and lower MBL serum levels (P<0.001).The “L” and “Y” alleles were linked to faster disease progression in native kidneys but not during transplantation.Notably, patients with low MBL levels had worse graft outcome (P = 0.0023) over an average follow-up of 151 months. Conclusion: Low MBL levels are associated with graft dysfunction in kidney transplant recipients with IgAN.This finding highlights the importance of monitoring MBL levels as a potential marker for graft prognosis in these patients. Funding: Clinical Revenue Support