Guillaume Claisse1, Lena Absi2, Fabrice Cognasse3, Eric Alamartine4, Christophe Mariat5, Nicolas Maillard6. 1. Service de Néphrologie et Transplantation Rénale, Hôpital NORD, CHU de Saint-Etienne, Université Jean MONNET, 42055 Saint-Etienne cedex 02, France. Electronic address: claisse.guillaum@gmail.com. 2. Laboratoire d'Immunologie, EFS Loire-Auvergne, 25 Boulevard Pasteur, 42100 Saint-Etienne, France. Electronic address: Lena.Absi@efs.sante.fr. 3. GIMAP - EA3064, COMUE Université de Lyon, 42055 Saint-Etienne cedex 02, France; Laboratoire d'Immunologie, EFS Loire-Auvergne, 25 Boulevard Pasteur, 42100 Saint-Etienne, France. Electronic address: fabrice.cognasse@univ-st-etienne.fr. 4. Service de Néphrologie et Transplantation Rénale, Hôpital NORD, CHU de Saint-Etienne, Université Jean MONNET, 42055 Saint-Etienne cedex 02, France; GIMAP - EA3064, COMUE Université de Lyon, 42055 Saint-Etienne cedex 02, France. Electronic address: eric.alamartine@univ-st-etienne.fr. 5. Service de Néphrologie et Transplantation Rénale, Hôpital NORD, CHU de Saint-Etienne, Université Jean MONNET, 42055 Saint-Etienne cedex 02, France; GIMAP - EA3064, COMUE Université de Lyon, 42055 Saint-Etienne cedex 02, France. Electronic address: christophe.mariat@univ-st-etienne.fr. 6. Service de Néphrologie et Transplantation Rénale, Hôpital NORD, CHU de Saint-Etienne, Université Jean MONNET, 42055 Saint-Etienne cedex 02, France; GIMAP - EA3064, COMUE Université de Lyon, 42055 Saint-Etienne cedex 02, France. Electronic address: nicolas.maillarda@gmail.com.
Abstract
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.
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.
Authors: Maria Meneghini; Edoardo Melilli; Jaume Martorell; Ignacio Revuelta; Elisabet Rigol-Monzó; Anna Manonelles; Nuria Montero; David Cucchiari; Fritz Diekmann; Josep M Cruzado; Salvador Gil-Vernet; Josep M Grinyó; Oriol Bestard Journal: Kidney Int Rep Date: 2018-03-30
Authors: Anat R Tambur; Patricia Campbell; Anita S Chong; Sandy Feng; Mandy L Ford; Howard Gebel; Ronald G Gill; Garnett Kelsoe; Vasilis Kosmoliaptsis; Roslyn B Mannon; Michael Mengel; Elaine F Reed; Nicole M Valenzuela; Chris Wiebe; I Esme Dijke; Harold C Sullivan; Peter Nickerson Journal: Am J Transplant Date: 2020-05-27 Impact factor: 8.086