{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\n Glycophorin B (GYPB) is an abundant sialoglycoprotein on the erythrocyte surface that serves several critical functions. A major role for GYPB is in malaria pathogenesis, where it acts as an essential receptor for Plasmodium falciparum invasion. Notably, studies have demonstrated that GYPB serves as the receptor for the parasite ligand EBL‐1, with certain parasite strains showing marked dependence on this protein during erythrocyte invasion."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": " In addition, allelic variations in GYPB, particularly the GYPB*S/s alleles, are associated with differential susceptibility to infection in malaria‐endemic regions, underscoring the epidemiological importance of this glycoprotein."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "3"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n "}, {"type": "p", "children": [{"type": "t", "text": "\n Beyond its role in parasite entry, GYPB is a key determinant of the MNS blood group system. The presence or complete deletion of GYPB defines the expression of the S/s antigens and the U antigen on red blood cells, with complete GYPB deletions being the basis for the U‐negative phenotype observed primarily in individuals of African descent."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "5"}]}, {"type": "t", "text": " Furthermore, GYPB contributes to the organization and stability of the red cell membrane by participating in complexes with other membrane proteins, such as those of the Rh antigen system; alterations in GYPB content, for example in hybrid forms like GP.Mur, correlate with reduced expression of Rh antigens, indicating its structural as well as immunohematologic significance."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "6"}]}, {"type": "t", "text": "\n "}]}, {"type": "t", "text": "\n "}, {"type": "p", "children": [{"type": "t", "text": "\n Finally, the antigenic determinants of GYPB are central to blood group serology. Detailed epitope mapping using monoclonal antibodies has revealed that the S/s antigenic determinants reside on specific regions of GYPB, information that is crucial for both transfusion medicine and for understanding immune responses against variant glycophorins."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "7"}]}, {"type": "t", "text": " Moreover, the regulation of GYPB gene expression in the erythroid lineage by transcription factors further helps to explain the diversity observed in blood group phenotypes, emphasizing the broader physiological relevance of this molecule."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "9"}]}, {"type": "t", "text": "\n "}]}, {"type": "rg", "children": [{"type": "r", "ref": 1, "children": [{"type": "t", "text": "D C Ghislaine Mayer, Joann Cofie, Lubin Jiang, et al. 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"}, {"type": "b", "children": [{"type": "t", "text": "Population genetics of GYPB and association study between GYPB*S/s polymorphism and susceptibility to P. falciparum infection in the Brazilian Amazon."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "PLoS One (2011)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1371/journal.pone.0016123"}], "href": "https://doi.org/10.1371/journal.pone.0016123"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "21283638"}], "href": "https://pubmed.ncbi.nlm.nih.gov/21283638"}]}, {"type": "r", "ref": 4, "children": [{"type": "t", "text": "Philaiphon Jongruamklang, Shane Grimsley, Nicole Thornton, et al. "}, {"type": "b", "children": [{"type": "t", "text": "Characterization of GYP"}, {"type": "i", "children": [{"type": "t", "text": "Mur and novel GYP"}]}, {"type": "t", "text": "Bun-like hybrids in Thai blood donors reveals a qualitatively altered s antigen."}]}, {"type": "t", "text": " "}, {"type": "i", "children": [{"type": "t", "text": "Vox Sang (2020)"}]}, {"type": "t", "text": " DOI: "}, {"type": "a", "children": [{"type": "t", "text": "10.1111/vox.12909"}], "href": "https://doi.org/10.1111/vox.12909"}, {"type": "t", "text": " PMID: "}, {"type": "a", "children": [{"type": "t", "text": "32201961"}], "href": "https://pubmed.ncbi.nlm.nih.gov/32201961"}]}, {"type": "r", "ref": 5, "children": [{"type": "t", "text": "William J Lane, Nicholas S Gleadall, Judith Aeschlimann, et al. 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