title: Immunohistochemistry analysis of pulmonary infiltrates in necropsy samples of children with non-pandemic lethal respiratory infections (RSV; ADV; PIV1; PIV2; PIV3; FLU A; FLU B).
abstract: BACKGROUND
  Acute viral respiratory infections represent a globally important cause of morbidity and mortality in childhood. An individual's cellular response appears to play a critical role in recovery from infections, given that individuals with impaired cellular immunity, congenital or acquired, have more severe diseases and secrete the virus for longer periods.
  
  
  OBJECTIVE
  The aim of this study was to immunohistochemically evaluate the expression of the cell surface antigens CD4, CD8, CD25, CD14 and CD74, in pneumonic infiltrates in the alveolar septa using paraffin-embedded lung samples from autopsies of immunocompetent children who died of lethal, non-pandemic, severe acute respiratory infections.
  
  
  METHODS
  From 794 cases of pediatric autopsies of patients with severe respiratory disease (between 1960 and 2004), 193 cases were selected for this study. To identify subpopulations of inflammatory cells in the alveolar septa, cell surface antigen expression was assessed by immunohistochemistry using the following primary antibodies: anti-CD4, anti-CD8, anti-CD14, anti-CD25 and anti-CD74.
  
  
  RESULTS
  The TCD8+ lymphocyte count was higher in the virus-positive group (p = 0.04) and was also much higher among cases that were positive for more than three viral types (p = 0.016). There were fewer CD14+ cells in cases of AdV (adenovirus) infection (p = 0.002), and there was a predominance of CD74+ cells in the histopathological pattern defined as interstitial pneumonitis (p = 0.037).
  
  
  CONCLUSIONS
  The results of this study demonstrate that TCD8+ lymphocytes present in the alveolar septa participate to a greater extent in the response toward viral pneumonia, while CD14+ cell numbers are often reduced in cases of AdV.
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: victor.costajr@gmail.com.
authors: Victor Horácio
authors: VH
authors: de Souza Costa
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: manubaurakiades@gmail.com.
authors: Emanuele
authors: E
authors: Baurakiades
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: malu_tu@yahoo.com.br.
authors: Marina Louise
authors: ML
authors: Viola Azevedo
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: gabrielatraiano@hotmail.com.
authors: Gabriela
authors: G
authors: Traiano
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: jeana-jkr@hotmail.com.
authors: Jeana
authors: J
authors: Kowal Rosales
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: kskl@onda.com.br.
authors: Kelly Susana
authors: KS
authors: Kunze Larsen
authors: Universidade Federal do Paraná - Hospital de Clínicas, Rua General Carneiro, 181 Centro, Curitiba, Paraná, Brazil. Electronic address: sraboni@ufpr.br.
authors: Sonia Maria
authors: SM
authors: Raboni
authors: Pontifícia Universidade Católica do Paraná, Rua Imaculada Conceição, 1155 Prado Velho, Curitiba, Paraná, Brazil. Electronic address: lnno@terra.com.br.
authors: Lucia
authors: L
authors: de Noronha
mesh_terms: D000293:Adolescent; D015703:Antigens, CD / Q000032:analysis; D001344:Autopsy; D002648:Child; D006801:Humans; D007150:Immunohistochemistry; D007223:Infant; D008168:Lung / Q000473:pathology*; D008297:Male; D011650:Pulmonary Alveoli / Q000473:pathology; D012141:Respiratory Tract Infections / Q000276:immunology / Q000473:pathology*; D014777:Virus Diseases / Q000276:immunology / Q000473:pathology*
chemical_list: D015703:Antigens, CD
keywords: Autopsy; Childhood; Immunohistochemistry; Pneumonia; Virus