title: Association of apoptosis inhibitor of macrophage (AIM) expression with urinary protein and kidney dysfunction.
abstract: BACKGROUND
  Apoptosis inhibitor of macrophage (AIM) expressed on macrophages prolongs inflammation by protecting macrophages from apoptosis. Most circulating AIM co-exists with immunoglobulin M (IgM). AIM's pathophysiological role in relation to IgM remains unclear. Here we evaluated the glomerular expression/deposition of AIM and IgM in the kidney using immunohistochemistry and its associations with clinical manifestations in 43 patients with biopsy-confirmed kidney diseases.
  
  
  METHODS
  Kidney biopsy tissue from all patients was immunostained for AIM and IgM. Staining patterns and percent stained areas within the glomeruli were determined. Cells expressing AIM were identified by co-staining with macrophage and endothelial cell surface markers. Correlations between staining results and clinical parameters were evaluated using univariate and multivariate analyses.
  
  
  RESULTS
  AIM was deposited in various areas, such as mesangial and capillary area. A part of AIM expression was localized to CD68-positive macrophages in the glomerulus. Amount of glomerular expression was positively correlated with urinary protein in patients with severe proteinuria (urinary protein ≥0.5 g/day) and kidney dysfunction [estimated glomerular filtration ratio (eGFR) <60 ml/min/1.73 m2]. Urinary protein was higher in patients exhibiting overlapping glomerular expression of AIM and IgM. Annual eGFR decline rate negatively correlated with AIM-positive area. AIM-positive area and initial serum creatinine were independently associated with decreased kidney function.
  
  
  CONCLUSIONS
  AIM expression in the kidney was associated with urinary protein and decline in kidney function. Co-expression with IgM appeared to exacerbate AIM's deleterious effects on kidney function. Combined glomerular AIM and IgM expression is a candidate prognostic index for kidney disease.
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Megumi
authors: M
authors: Oshima
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan. iwata-knz@umin.ac.jp.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan. iwata-knz@umin.ac.jp.|Division of Infection Control, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan. iwata-knz@umin.ac.jp.
authors: Yasunori
authors: Y
authors: Iwata
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Kengo
authors: K
authors: Furuichi
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Norihiko
authors: N
authors: Sakai
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Miho
authors: M
authors: Shimizu
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Akinori
authors: A
authors: Hara
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Shinji
authors: S
authors: Kitajima
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Tadashi
authors: T
authors: Toyama
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Yasuyuki
authors: Y
authors: Shinozaki
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Akihiro
authors: A
authors: Sagara
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.
authors: Eri
authors: E
authors: Umeda
authors: Department of Disease Control and Homeostasis, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Shuichi
authors: S
authors: Kaneko
authors: Laboratory of Molecular Biomedicine for Pathogenesis, Faculty of Medicine, Center for Disease Biology and Integrative Medicine, The University of Tokyo, Tokyo, Japan.
authors: Satoko
authors: S
authors: Arai
authors: Laboratory of Molecular Biomedicine for Pathogenesis, Faculty of Medicine, Center for Disease Biology and Integrative Medicine, The University of Tokyo, Tokyo, Japan.
authors: Toru
authors: T
authors: Miyazaki
authors: Division of Nephrology, Kanazawa University Hospital, Kanazawa, Ishikawa, Japan.|Department of Laboratory Medicine, Faculty of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Ishikawa, Japan.
authors: Takashi
authors: T
authors: Wada
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D051017:Apoptosis Regulatory Proteins; D001706:Biopsy; D042783:Endothelial Cells / Q000737:chemistry; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis; D007150:Immunohistochemistry; D007674:Kidney Diseases / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D007678:Kidney Glomerulus / Q000737:chemistry* / Q000473:pathology / Q000503:physiopathology; D008264:Macrophages / Q000737:chemistry; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011507:Proteinuria / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology; D051116:Receptors, Scavenger / Q000032:analysis*; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D051017:Apoptosis Regulatory Proteins; C492821:CD5L protein, human; D007075:Immunoglobulin M; D051116:Receptors, Scavenger
keywords: Apoptosis inhibitor of macrophage (AIM); IgM; Kidney disease