title: Pilot investigation of the association between serum stress neuropeptide levels and lymphocyte expression of fas and fas ligand in critical illness.
abstract: BACKGROUND
  In critical illness, apoptotic loss of immunocytes is associated with immunosuppression.
  
  
  OBJECTIVE
  To explore expression of Fas/Fas ligand (FasL) on B and T cells from critically ill patients without sepsis compared to matched controls and associations with disease severity and neuropeptide Y (NPY), cortisol, adrenocorticotropic hormone (ACTH), and prolactin (PRL) levels.
  
  
  METHODS
  Repeated-measures correlational design with 36 critically ill patients (14-day follow-up) and 36 controls. Disease severity was assessed using the Multiple Organ Dysfunction Score (MODS) and Multi Organ Failure scale. Fas/FasL values were standardized for viable cell counts. An enzyme-linked immunosorbent assay (NPY) and electrochemiluminescence immunoassay (cortisol, ACTH, and PRL) were employed.
  
  
  RESULTS
  Fas and FasL expression on T-helper (p < .0001-.03) and T-cytotoxic cells (p < .0001-.002) and Fas expression on B cells (p < .0001-.03) were higher in patients. MODS severity was associated with FasL expression on cytotoxic T cells (r = .752-.902, p = .023-.037). There was an inverse association between Day 1 NPY levels and Fas expression on T-helper cells (r = -.447, p = .019). On the day of maximum severity, we report for the first time an inverse association between NPY levels and FasL expression on helper (r = -.733, p = .016) and cytotoxic (r = -.862, p = .003) T cells. Cortisol levels were positively associated with counts of FasL-positive helper (r = .828) and cytotoxic (r = .544, p < .05) T cells.
  
  
  CONCLUSIONS
  Results suggest a potential role for stress neuropeptides in lymphocyte survival and activation in critical illness.
authors.affiliation: Department of Nursing, Cyprus University of Technology, Limassol, Cyprus e.papathanassoglou@cut.ac.cy.
authors.forename: Elizabeth D E
authors.initials: ED
authors.lastname: Papathanassoglou
authors.affiliation: Department of Nursing B, Faculty of Health and Caring Professions, Technological Educational Institute of Athens, Egaleo, Greece.
authors.forename: Meropi D A
authors.initials: MD
authors.lastname: Mpouzika
authors.affiliation: University of Athens, School of Nursing, Athens, Hellas, Greece.
authors.forename: Margarita
authors.initials: M
authors.lastname: Giannakopoulou
authors.affiliation: University of Athens, School of Nursing, Athens, Hellas, Greece.
authors.forename: Evangelos
authors.initials: E
authors.lastname: Bozas
authors.affiliation: Department of Nursing, Cyprus University of Technology, Limassol, Cyprus.
authors.forename: Nicos
authors.initials: N
authors.lastname: Middleton
authors.affiliation: Department of Pathophysiology, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Sofia
authors.initials: S
authors.lastname: Boti
authors.affiliation: Surgical Care Unit, Onassis Cardiac Surgery Center, Athens, Greece.
authors.forename: Andreas
authors.initials: A
authors.lastname: Karabinis
mesh_terms: D000324:Adrenocorticotropic Hormone / Q000097:blood; D001402:B-Lymphocytes / Q000737:chemistry; D016638:Critical Illness; D004797:Enzyme-Linked Immunosorbent Assay; D053222:Fas Ligand Protein / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008214:Lymphocytes / Q000737:chemistry*; D009102:Multiple Organ Failure / Q000097:blood; D009478:Neuropeptide Y / Q000097:blood*; D010865:Pilot Projects; D011388:Prolactin / Q000097:blood; D012720:Severity of Illness Index; D013601:T-Lymphocytes / Q000737:chemistry
chemical_list: D053222:Fas Ligand Protein; D009478:Neuropeptide Y; D000324:Adrenocorticotropic Hormone; D011388:Prolactin; D006854:Hydrocortisone
keywords: PBMC; apoptosis; critical illness; neuropeptides; stress