A Novel Biomarker for Post-Transplant Recurrent IgA Nephropathy

作者：Temurhan S; Akgul S U; Caliskan Y^*; Artan A S; Kekik C; Yazici H; Demir E; Caliskan B; Turkmen A; Oguz F S; Sever M S

来源：Transplantation Proceedings, 2017, 49(3): 541-545.

DOI：10.1016/j.transproceed.2017.02.003

Background. The serum levels of galactose-deficient immunoglobulin (Ig)A1 (Gd-IgAl) represent the most promising candidate biomarker for IgA nephropathy (IgAN). The aim of this study was to evaluate the serum levels of Gd-IgAl as a novel noninvasive biomarker for post-transplant IgAN recurrence.
Methods. Serum Gd-IgAl levels of 18 patients with recurrent IgAN were compared with control renal transplant recipients (n = 23) with non-recurrent IgAN and control non transplant IgAN patients (n = 44) and healthy relatives (n = 11). Serum Gd-IgA1 levels of patients were measured with the use of KM55 enzyme-linked immunosorbent assay (ELISA). The effects of serum Gd-IgA1 concentrations on IgAN recurrence, post transplant events, and graft survival were evaluated.
Results. All recurrent IgAN patients presented with renal dysmean serum creatinine, 1.62 +/- 0.39 mg/dL) and detectable proteinuria at the time of diagnosis. Serum Gd-IgA1 levels of recurrent IgAN patients (8735 +/- 10854 ng/mL [log10: 3.71 +/- 0.45]) were significantly higher than those of non-recurrent IgAN patients (4790 +/- 6089 ng/mu L [log10: 3.31 +/- 0.64]) (P =.027). Serum Gd-lgAl levels of non-transplant IgAN patients were significantly higher (8791 +/- 8700 ng/mu L [log10: 3.79 +/- 0.36]) than those of non recurrent IgAN patients (4790 +/- 6089 ng/mu L [1og10: 3.31 +/- 0.64]) and healthy relatives (2615 +/- 1611 ng/mu L [log10: 3.34 +/- 0.27]) (P <.001 and P =.021, respectively). Receiver-operating characteristic curve analysis revealed that the area under the curve for recurrence of IgAN was 0.69 (0.53-0.85) for serum Gd-IgA1 (P =.038). Biopsy confirmed allograft rejection rates were similar in the recurrent IgAN group [3 (17%)] compared with the non-recurrent IgAN [6 (26%)] group (P =.47). Graft failure rate was not also significantly different in the recurrent IgAN group [4 (22.2%)] compared with the non-recurrent IgAN group [2 (8.7%)] (P =.224).
Conclusions. This novel lectin-independent Gd-IgAl ELISA that can detect serum Gd-IgAl in patients with recurrent IgAN can be used as a biomarker for diagnosis and activity assessment of post-transplant recurrent IgAN.

• 出版日期2017-4