title: The evaluation of metallothionein expression in nasal polyps with respect to immune cell presence and activity.
abstract: BACKGROUND
  The expression of metallothionein (MT) is involved in acquiring resistance to immune-mediated apoptosis; it is also a negative regulator of the immune response. Nasal polyps are typified by a resistance to immune-mediated apoptosis as well as by excessive immune cell infiltration. RCAS1 (receptor-binding cancer antigen expressed on SiSo cells) is a membrane protein capable of inducing the apoptosis of CTLs and NK cells. The aim of the present study has been to explore the expression of metallothionein with respect to immune cell presence and immune cell activity. In our study, we identified immune cells using CD4 and CD68 antigen expression and evaluated their activity using CD25 antigen expression. We then analyzed metallothionein, RCAS1, CD25, CD4, and CD68 in a sampling of 50 nasal polyps using the immunohistochemistry method. We were able to divide the nasal polyps into three main groups according to their predominant immune cell infiltration: eosinophilic nasal polyps (21 cases), lymphocytic nasal polyps (17 cases), and neutrophilic nasal polyps (12 cases).
  
  
  RESULTS
  In the present study, statistically significant differences between the MT expression in the epithelium and that in the stroma of the nasal polyps along with the accompanying alterations in activation markers on immune cells were found and the number of macrophages in both the eosinophilic and the lymphocytic nasal polyps was assessed. RCAS1-expressing macrophages were found only in the eosinophilic nasal polyps.
  
  
  CONCLUSIONS
  MT expression seems to favor the survival of nasal polyp epithelial cells in the adjacent area of increasingly cytotoxic immune activity. RCAS1-expressing macrophages seem to participate in creating the immune suppressive microenvironment and so help to sustain local inflammation.
authors.affiliation: Otolaryngology Head and Neck Surgery Department, Jagiellonian University, Sniadeckich 2, Krakow 31-531, Poland. mowicher@gmail.com
authors.forename: Magdalena
authors.initials: M
authors.lastname: Dutsch-Wicherek
authors.forename: Romana
authors.initials: R
authors.lastname: Tomaszewska
authors.forename: Agata
authors.initials: A
authors.lastname: Lazar
authors.forename: Paweł
authors.initials: P
authors.lastname: Strek
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Wicherek
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Piekutowski
authors.forename: Wojciech
authors.initials: W
authors.lastname: Jóźwicki
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis / Q000235:genetics; D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D017209:Apoptosis / Q000276:immunology; D002465:Cell Movement; D002908:Chronic Disease; D003602:Cytotoxicity, Immunologic; D004804:Eosinophils / Q000473:pathology; D006801:Humans; D008214:Lymphocytes / Q000473:pathology; D008668:Metallothionein / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D009297:Nasal Mucosa / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D009298:Nasal Polyps; D009504:Neutrophils / Q000473:pathology; D012220:Rhinitis / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D012852:Sinusitis / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology; D017154:Stromal Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology
chemical_list: D015703:Antigens, CD; D000951:Antigens, Neoplasm; C120762:EBAG9 protein, human; D008668:Metallothionein