title: Very low residual concentrations of rituximab long after infusion still induce positive B-cell complement-dependent cytotoxicity-crossmatch.
abstract: Rituximab may induce positive B-cell complement-dependent cytotoxicity crossmatch (CDC-XM) in the absence of donor-specific antibodies, as we report in these two cases. We retrospectively assessed the in vitro concentration-effect relationship of rituximab in sera. B-cell CDC-XM results were positive only in the presence of rituximab, even with low concentrations (inferior to 1 μg/mL). Moreover, rituximab neutralization with increasing concentration of an anti-rituximab-idiotype monoclonal antibody progressively reduced B-cell lysis. In conclusion, measurement of rituximab content may be useful to identify sera at risk of misinterpretation in immunized patients.
authors.forename: Philippe
authors.initials: P
authors.lastname: Gatault
authors.affiliation: CHRU de Tours, Department of Nephrology and Transplantation, Tours, France; Université François-Rabelais, EA 4245 Tours, France.
authors.forename: Gatault
authors.initials: G
authors.lastname: Philippe
authors.forename: Isabelle
authors.initials: I
authors.lastname: Jollet
authors.forename: Jollet
authors.initials: J
authors.lastname: Isabelle
authors.forename: Gilles
authors.initials: G
authors.lastname: Paintaud
authors.forename: Paintaud
authors.initials: P
authors.lastname: Gilles
authors.forename: Charlotte
authors.initials: C
authors.lastname: Magdelaine
authors.forename: Magdelaine
authors.initials: M
authors.lastname: Charlotte
authors.forename: Franck
authors.initials: F
authors.lastname: Bridoux
authors.forename: Bridoux
authors.initials: B
authors.lastname: Franck
authors.forename: Yvon
authors.initials: Y
authors.lastname: Lebranchu
authors.forename: Lebranchu
authors.initials: L
authors.lastname: Yvon
authors.forename: Matthias
authors.initials: M
authors.lastname: Büchler
authors.forename: Büchler
authors.initials: B
authors.lastname: Matthias
authors.forename: Guy
authors.initials: G
authors.lastname: Touchard
authors.forename: Touchard
authors.initials: T
authors.lastname: Guy
authors.forename: Antoine
authors.initials: A
authors.lastname: Thierry
authors.forename: Thierry
authors.initials: T
authors.lastname: Antoine
mesh_terms: D058846:Antibodies, Monoclonal, Murine-Derived / Q000008:administration & dosage / Q000493:pharmacokinetics*; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D003165:Complement System Proteins / Q000276:immunology*; D003602:Cytotoxicity, Immunologic / Q000187:drug effects*; D006084:Graft Rejection / Q000276:immunology / Q000517:prevention & control; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007155:Immunologic Factors / Q000008:administration & dosage / Q000493:pharmacokinetics*; D016030:Kidney Transplantation / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D000069283:Rituximab
chemical_list: D058846:Antibodies, Monoclonal, Murine-Derived; D016756:Immunoglobulins, Intravenous; D007155:Immunologic Factors; D000069283:Rituximab; D003165:Complement System Proteins
keywords: CDC; DSA; HLA; IvIg; SA; XM; complement-dependent cytotoxicity; crossmatch; donor-specific antibodies; human leucocyte antigen; intravenous immunoglobulin; single antigen