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Updated: Mar 7, 2026
Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion
Published on: June 15, 2019
Relationship between Mean Fluorescence Intensity and C1q/C3d-fixing capacities of anti-HLA antibodies
Guillaume Claisse1, Lena Absi2, Fabrice Cognasse3
1Service de Néphrologie et Transplantation Rénale, Hôpital NORD, CHU de Saint-Etienne, Université Jean MONNET, 42055 Saint-Etienne cedex 02, France.
Background:
Complement-binding assays are proposed to better stratify the risk of antibody-mediated rejection associated-graft failure. Despite promising clinical results, some have suggested that the MFI of anti-HLA antibodies may influence these tests.
Methods:
We investigated the impact of Abs MFI reduction, induced by plasmapheresis, on C1q- and C3d-binding assays. Sera provided from 7 sensitized kidney transplant patients were analyzed.
Results:
Four hundreds and thirty-three SABs were analyzed. Before plasmapheresis, when compared to C1q- SABs, C1q+ SABs had a higher median MFI [17397 (IQR: 14851-18794) vs. 2745 (IQR: 1125-6476), p<0.01]. SABs that remained C1q+ after plasmapheresis had a higher median MFI. Regarding the C3d assay, results were strictly comparable. MFI value was a powerful predictor of both C1q and C3d positivity [AUC 0.97 (CI95% 0.95-0.99) and 0.96, (CI95% 0.93-0.98), respectively].
Conclusion:
Our data suggest that both C1q- and C3d-binding assays are intimately linked to the MFI of anti-HLA Abs.
