Marginal zone B cells acquire dendritic cell functions by trogocytosis

• Published in: Science (American Association for the Advancement of Science) Vol. 375; no. 6581; p. eabf7470
• Main Authors: Schriek, Patrick, Ching, Alan C, Moily, Nagaraj S, Moffat, Jessica, Beattie, Lynette, Steiner, Thiago M, Hosking, Laine M, Thurman, Joshua M, Holers, V Michael, Ishido, Satoshi, Lahoud, Mireille H, Caminschi, Irina, Heath, William R, Mintern, Justine D, Villadangos, Jose A
• Format: Journal Article
• Language: English
• Published: United States The American Association for the Advancement of Science 11.02.2022
• Subjects: Adaptive immunity; Adult; Animals; Antibodies; Antigen Presentation; Antigens; B-Lymphocytes - immunology; B-Lymphocytes - metabolism; Carbohydrates; Cell Membrane - metabolism; Complement; Complement Activation; Complement C3 - immunology; Complement C3 - metabolism; Complement component C3; Complement receptor 2; Complement system; Covalent bonds; Damage prevention; Dendritic cells; Dendritic Cells - immunology; Dendritic Cells - metabolism; Dendritic structure; Female; Histocompatibility Antigens Class II - metabolism; HLA-D Antigens - immunology; HLA-D Antigens - metabolism; Humans; Immune system; Immunity; Immunoglobulin M; Immunological memory; Immunology; Lymphocytes; Lymphocytes B; Lymphocytes T; Lymphoid tissue; Lymphoid Tissue - immunology; Major histocompatibility complex; Male; Membranes; Memory cells; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Mice, Inbred C57BL; Microorganisms; Middle Aged; Neonates; Pathogens; Peptides; Plasma membranes; Proteins; Receptors; Receptors, Complement 3d - immunology; Receptors, Complement 3d - metabolism; Serum proteins; T-Lymphocytes - immunology; Trogocytosis; Ubiquitin; Ubiquitin-protein ligase; Ubiquitin-Protein Ligases - genetics; Ubiquitin-Protein Ligases - metabolism; Ubiquitination
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.abf7470

Marginal zone (MZ) B cells produce broad-spectrum antibodies that protect against infection early in life. In some instances, antibody production requires MZ B cells to display pathogen antigens bound to major histocompatibility complex class II (MHC II) molecules to T cells. We describe the trogocytic acquisition of these molecules from conventional dendritic cells (cDCs). Complement component 3 (C3) binds to murine and human MHC II on cDCs. MZ B cells recognize C3 with complement receptor 2 (CR2) and trogocytose the MHC II-C3 complexes, which become exposed on their cell surface. The ubiquitin ligase MARCH1 limits the number of MHC II-C3 complexes displayed on cDCs to prevent their elimination through excessive trogocytosis. Capture of C3 by MHC II thus enables the transfer of cDC-like properties to MZ B cells.