Calprotectin (S100A8/S100A9) and Myeloperoxidase: Co-Regulators of Formation of Reactive Oxygen Species

Inflammatory mediators trigger polymorphonuclear neutrophils (PMN) to produce reactive oxygen species (ROS: O2-, H2O2, ∙OH). Mediated by myeloperoxidase in PMN, HOCl is formed, detectable in a chemiluminescence (CL) assay. We have shown that the abundant cytosolic PMN protein calprotectin (S100A8/A9) similarly elicits CL in response to H2O2 in a cell-free system. Myeloperoxidase and calprotectin worked synergistically. Calprotectin-induced CL increased, whereas myeloperoxidase-triggered CL decreased with pH > 7.5. Myeloperoxidase needed NaCl for CL, calprotectin did not. 4-hydroxybenzoic acid, binding ∙OH, almost abrogated calprotectin CL, but moderately increased myeloperoxidase activity. The combination of native calprotectin, or recombinant S100A8/A9 proteins, with NaOCl markedly enhanced CL. NaOCl may be the synergistic link between myeloperoxidase and calprotectin. Surprisingly- and unexplained- at higher concentration of S100A9 the stimulation vanished, suggesting a switch from pro-oxidant to anti-oxidant function. We propose that the ∙OH is predominant in ROS production by calprotectin, a function not described before

Drug testing: Findings of opiates in urine after ingestion of poppy seeds

Background: It is known that poppy seeds may contain opiates naturally, i.e. morphine and codeine. Morphine and codeine, however, are also commonly used drugs. Drug tests in urine being positive for opiates are sometimes explained by the consumption of poppy seeds in the form of baked goods. In such cases it can be challenging to determine what was actually ingested. The aim of this study was to examine the amount of poppy seeds needed to be ingested to yield positive opiate results with our analytical methods. Material and methods: In all, 16 volunteers divided into 4 groups (A-D) ate poppy seeds from either (A) 1-4 rolls, (B) 1-4 crisp breads, (C) spice jar (48 grams) or (D) spice bag (48 grams). Urine samples collected during the following 24 hours were analyzed with immunological screening method and specific chromatographic method (LC-MSMS). Results: No samples from group A and B were positive with the immunological method, but one subject in group B (4 crisp breads) was positive for morphine with the chromatographic method. In groups C and D all subjects had two or more positive tests measured with immunological and chromatographic method. There were significant differences in measured levels between groups C and D. No samples contained higher concentration of codeine than morphine in this study. Interpretation: Consumption of poppy seeds can yield positive test results for opiates, depending on the quantity of poppy seeds consumed. Consumption of the same amount of poppy seeds can produce very different levels of opiates depending on the type and origin of the seeds ingested