title: Clinical relevance of the severe abnormalities of the T cell compartment in septic shock patients.
abstract: BACKGROUND
  Given the pivotal role of T lymphocytes in the immune system, patients with septic shock may show T cell abnormalities. We have characterised the T cell compartment in septic shock and assess its clinical implications.
  
  
  METHODS
  T lymphocytes from the peripheral blood of 52 patients with septic shock and 36 healthy control subjects were analysed on admission to the intensive care unit, baseline, and 3, 7, 14 and 28 days later. T cell phenotypes (CD3+CD4+/CD3+CD8+, CD45RA+/CD45RO+, CD62L+/CD28+) were assessed by quantitative flow cytometry.
  
  
  RESULTS
  CD3+, CD3+CD4+ and CD3+CD8+ lymphocyte counts were significantly lower in patients with septic shock than control subjects. In surviving patients, CD3+CD4+ lymphocytes had normalised after 14 days, yet CD3+CD8+ numbers were still low. Non effector CD45RA+CD45RO- subsets of CD3+CD4+ and CD3+CD8+ were persistently low during patient follow up. CD3+CD8+CD28+ and CD3+CD8+CD62L+ were reduced in patients versus controls and survivors versus nonsurvivors in the first three days. A prediction receptor operative curve revealed that for the CD3+CD8+CD28+ subset, a cutoff of 136 cells/ml showed 70% sensitivity and 100% specificity for predicting death and the area under the curve was 0.84 at admission. Corresponding values for CD3+CD8+CD62L+ were 141 cells/ml, 60% sensitivity, 100% specificity and an area under the curve of 0.75.
  
  
  CONCLUSIONS
  A severe redistribution of T lymphocyte subsets is found in septic shock patients. A different kinetic pattern of T cell subset involvement is observed in surviving and nonsurviving patients, with lower numbers of circulating CD3+CD8+CD28+ and CD3+CD8+CD62L+ associated with a better disease outcome.
authors.affiliation: Department of Medicine (CNB-CSIC) Associated Unit, Laboratory of Immune System Diseases and Oncology, National Biotechnology Center, University of Alcalá, Alcalá de Henares, Madrid, Spain. jorge.monserrat@uah.es
authors.forename: Jorge
authors.initials: J
authors.lastname: Monserrat
authors.forename: Raul
authors.initials: R
authors.lastname: de Pablo
authors.forename: Eduardo
authors.initials: E
authors.lastname: Reyes
authors.forename: David
authors.initials: D
authors.lastname: Díaz
authors.forename: Hugo
authors.initials: H
authors.lastname: Barcenilla
authors.forename: Manuel R
authors.initials: MR
authors.lastname: Zapata
authors.forename: Antonio
authors.initials: A
authors.lastname: De la Hera
authors.forename: Alfredo
authors.initials: A
authors.lastname: Prieto
authors.forename: Melchor
authors.initials: M
authors.lastname: Alvarez-Mon
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000473:pathology; D018655:Lymphocyte Count / Q000379:methods / Q000639:trends; D008297:Male; D008875:Middle Aged; D012772:Shock, Septic / Q000097:blood* / Q000473:pathology*; D016176:T-Lymphocyte Subsets / Q000473:pathology*