title: Chemiluminescent analysis of light-irradiated leukocytes as a diagnostic tool for fast identification of pathological states.
abstract: OBJECTIVE
  Reactive oxygen species (ROS), mainly produced by polymorphonuclear neutrophils (PMN), are a significant part of host defense in pathologic states. We attempted to relate numbers of PMN and ROS generated within PMN to develop an alternative photochemical approach for evaluation of the potential of these cells to resist the development of inflammatory pathology.
  
  
  BACKGROUND
  Lack of sensitivity to light has been reported in healthy cells, while sensitivity to light characterizes cell pathology.
  
  
  METHODS
  Human leukocytes from 34 donors were isolated and irradiated with a non-laser blue light (2 and 5 mW/cm(2) for 2 minutes), and a luminol-dependent chemiluminescence assay that reflects intracellular production of ROS was applied thereafter. The levels of basal chemiluminescence (BCL) were related to respective numbers of PMN.
  
  
  RESULTS
  A light-insensitive cluster was discovered within the total sample and was considered to be a discrete nonpathological group. Following elimination of this group, the rest of the sample was divided into three well-defined light-sensitive groups, which were attributed to various pathological states, and differed in PMN numbers and BCL counts. Within these groups the two traits were interrelated, and each PMN range was associated with a respective level of intracellular ROS.
  
  
  CONCLUSIONS
  Leukocyte responsiveness to light can be used for discrimination between pathological and nonpathological states and prognostic evaluation of pathological development. Patients exhibiting similar clinical symptoms could be divided into separate groups with potentially different outcomes. A novel definition of nonpathological states as well as the mechanism underlying the bell-shaped curve that delineates the relationship between PMN number and intracellular ROS is suggested in pathological states.
authors.affiliation: The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel. sinyakov@mail.biu.ac.il
authors.forename: Michael S
authors.initials: MS
authors.lastname: Sinyakov
authors.forename: Tanya S
authors.initials: TS
authors.lastname: Shlenskaya
authors.forename: Sandro
authors.initials: S
authors.lastname: Belotsky
authors.forename: Helena M
authors.initials: HM
authors.lastname: Zhevelev
authors.forename: Bracha
authors.initials: B
authors.lastname: Shainberg
authors.forename: Rachel
authors.initials: R
authors.lastname: Lubart
authors.forename: Harry
authors.initials: H
authors.lastname: Friedmann
authors.forename: Ramy R
authors.initials: RR
authors.lastname: Avtalion
mesh_terms: D000704:Analysis of Variance; D002469:Cell Separation; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism; D007962:Leukocytes / Q000378:metabolism*; D008163:Luminescent Measurements; D008165:Luminol / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*