Diagnosis and dosimetry of exposure to sulfur mustard: Development of standard operating procedures. Further exploratory research on protein adducts
report
In continuation of previous grants, a tentative standard operating procedure has been developed for two methods for retrospective detection of exposure to sulfur mustard an immunoslotbiot assay andor ELISA for DNA adducts in blood and skin and the modified Edman procedure for determination of adducts to the N-terminal valine in hemoglobin. Both procedures could substantially be shortened, while their sensitivities were improved. Furthermore, exploratory research is performed aiming at the development of a fieldable immunochemical assay for sulfur mustard adducts with three proteins, i.e., hemoglobin, albumin, and keratin. Upon exposure of human blood to sulfur mustard, the major adducts in albumin are formed with histidine and cysteine-34 in the tryptic T5 peptide. Exposure to 10 nM sulfur mustard was determined by LC-tandem MS analysis of a tripeptide containing this adducted cysteine in a pronase digest of only 3 mg albumin, i.e., the most sensitive marker for exposure to sulfur mustard developed so far. Exposure of Iranian victims of the Iran-Iraq conflict was detected by using both this procedure and the modified Edman procedure. Treatment at pH 13 released 80 of the bound radioactivity as C-14thiodiglycol from keratin isolated from C-14sulfur mustard exposed human callus, which suggests that most of the adducts formed are esters of glutamic and aspartic acid residues. Exposure of human callue to 10 micro-M of sulfur mustard could be detected by GC-MS analysis of released thiodiglycol after derivatization. Three partial sequences of hemoglobin, the T5 fragment from albumin, and three partial sequences of keratin were synthesized and used as haptens for raising antibodies, which contain adducted histidine, cysteine, and glutamine or asparagine, respectively. Several clones have been obtained. Some of the antibodies directed against keratin adducts showed binding to the horny layer of human skin exposed to sulfur mustard Ct 1040 mg.min.cu m.
Topics
TNO Identifier
984333
Publisher
TNO
Collation
98 p.