title: Immunoglobulin M-enriched human intravenous immunoglobulins reduce leukocyte-endothelial cell interactions and attenuate microvascular perfusion failure in normotensive endotoxemia.
abstract: Clinical studies indicate potential differences in the efficacy of immunoglobulin (Ig) preparations in patients with sepsis. A recent meta-analysis showed improved survival rates with IgM-enriched Igs. It was the objective of the present study to characterize microcirculatory actions of different clinically used Ig preparations in a rodent endotoxin model by intravital microscopy. Male Syrian golden hamsters 6 to 8 weeks old with a body weight of 60 to 80 g were investigated by intravital fluorescence microscopy. Endotoxemia was induced by administration of 2 mg/kg (i.v.) endotoxin (LPS, Escherichia coli). Two different Ig preparations containing IgM, IgA, and IgG (intravenous IgM group; n = 6; 5 mL Pentaglobin/kg body weight, i.v.) or exclusively IgG (intravenous IgG group; n = 5; 5 mL Flebogamma/kg body weight, i.v.) were applied 5 min before LPS. Saline-treated endotoxemic animals served as controls (control; n = 8). In controls, LPS induced massive leukocyte-endothelial cell interactions, pronounced microvascular leakage, a decrease of systemic platelet count, and distinct capillary perfusion failure (P < 0.05). Both intravenous IgM and IgG reduced venular leakage (P< 0.05) and ameliorated the decrease in platelet count (P < 0.05). Of interest, intravenous IgM was capable of significantly (P< 0.05) reducing leukocyte adhesion in venules. This was associated with normalization of capillary perfusion at 24 h of endotoxemia, whereas intravenous IgG could not prevent LPS-mediated microvascular perfusion failure. We demonstrate that IgM-enriched Igs are superior to IgG alone in attenuating LPS-induced leukocytic inflammation and microcirculatory dysfunction. Our findings can explain better efficacy of IgM-enriched Igs in patients with severe sepsis.
authors.affiliation: Department of Surgery, Klinikum Grosshadern, Ludwig-Maximilians-University, Munich, Germany. Johannes.Hoffman@med.uni-muenchen.de
authors.forename: Johannes N
authors.initials: JN
authors.lastname: Hoffman
authors.forename: Jan M
authors.initials: JM
authors.lastname: Fertmann
authors.forename: Brigitte
authors.initials: B
authors.lastname: Vollmar
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Laschke
authors.forename: Karl W
authors.initials: KW
authors.lastname: Jauch
authors.forename: Michael D
authors.initials: MD
authors.lastname: Menger
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D006224:Cricetinae; D004195:Disease Models, Animal; D042783:Endothelial Cells / Q000187:drug effects / Q000502:physiology; D019446:Endotoxemia / Q000473:pathology / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D007074:Immunoglobulin G / Q000008:administration & dosage / Q000627:therapeutic use; D007075:Immunoglobulin M / Q000008:administration & dosage / Q000627:therapeutic use*; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use*; D036904:Leukocyte Rolling / Q000187:drug effects; D007962:Leukocytes / Q000187:drug effects / Q000502:physiology; D008070:Lipopolysaccharides / Q000633:toxicity; D008297:Male; D008647:Mesocricetus; D008833:Microcirculation / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D008856:Microscopy, Fluorescence; D018805:Sepsis / Q000473:pathology / Q000503:physiopathology / Q000628:therapy
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M; D016756:Immunoglobulins, Intravenous; D008070:Lipopolysaccharides