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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Adult, Blood Donors, Female, Fucose, Galactose, Glycosylation, Humans, Immunization, Immunoglobulin Fc Fragments, Immunoglobulin G, Isoantibodies, Male, Middle Aged, Pregnancy, Protein Processing, Post-Translational, Receptors, IgG, Rh Isoimmunization, Rho(D) Immune Globulin, Sex Characteristics, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization.
user
Do prophylactic anti-D preparations display variable decreases in Fc-fucosylation of anti-D? Context: RhIG is obtained from hyperimmunized healthy anti-D donors (HIDs) boosted with D+ red blood cells (RBCs). One hypothesis for its mechanism of action is fast clearance of opsonized D+ RBCs through Fcγ receptor (FcγR)III. Levels of immunoglobulin (Ig)G Fc-fucosylation influence interactions with FcγRIII, with less Fc-fucosylation strengthening the interaction. Anti-D IgG1 Fc-glycosylation patterns in 93 plasma samples from 28 male and 28 female Dutch HIDs and RhIG were analyzed with mass spectrometry. The Fc-glycosylation profiles of HIDs were evaluated with regard to their immunization history. HID sera demonstrated clearly lowered anti-D Fc-fucosylation compared to normal IgG fucosylation (93%); this was more pronounced for female than for male HIDs (47% vs. 65%, p = 0.001). RhIG preparations from seven manufacturers varied greatly in the level of Fc-fucosylation (56%-91%). The level of fucosylation slightly increased upon repeated immunization, although it remained fairly constant over time. The RhIG from the different manufacturers all demonstrated increased Fc-galactosylation (64%-82%) compared to total IgG (38%-51%).
assistant
RhIG preparations vary in Fc-fucosylation and all demonstrate increased galactosylation. Despite not knowing the exact working mechanism, immunoprophylaxis could perhaps be optimized by selection of donors whose anti-D have low amounts of Fc-fucose, to increase the clearance activity of anti-D preparations, as well as high amounts of galactosylation, for anti-inflammatory effects. Implementing a biologic assay in the standardization of RhIG preparations might be considered. Final Decision: yes