Lindh C H, Jönsson B A
Institute of Laboratory Medicine, University Hospital, Lund, SE-221 85, Sweden.
Toxicol Appl Pharmacol. 1998 Dec;153(2):152-60. doi: 10.1006/taap.1998.8540.
Hexahydrophthalic anhydride (HHPA) and methylhexahydrophthalic anhydride (MHHPA) are highly allergenic compounds used in the chemical industry. The aim of this study was to characterize the protein adducts in erythrocytes following exposure to HHPA and MHHPA. Blood and urine samples were obtained from 51 HHPA- and MHHPA-exposed workers. Erythrocytic proteins from HHPA- and MHHPA-exposed workers were fractionated by gel filtration and ion exchange chromatography. In vitro synthesized conjugates between tritium-labeled and unlabeled HHPA and hemoglobin (Hb) were hydrolyzed by acid or digested by Pronase E. Levels of in vivo formed anhydride-Hb adducts and urinary/plasma levels of the corresponding acids were analyzed by gas chromatography-mass spectrometry (GC-MS) and correlated. The decay of adducts was studied in workers leaving employment or during vacation. More than 85% of the adduct forming protein in vivo coeluted with Hb in gel filtration and ion exchange chromatography. At least 70% of the HHPA in the in vitro formed adducts was found on lysine by GC-MS. Similar findings were obtained using Pronase E-digested tritium-labeled Hb-HHPA. The adduct levels in workers ranged 0-26 pmol/g Hb (mean 2. 7 pmol/g Hb) for HHPA, and the range for MHHPA was 0-55 pmol/g Hb (mean 4.1 pmol/g Hb). The Spearman's rank correlation coefficient between urine data and adducts was for HHPA rs = 0.80 and for MHHPA, rs = 0.78. For the plasma, the correlation using HHPA data was rs = 0.80 and for MHHPA, rs = 0.69. The adducts seemed to be stable in vivo. The adduct levels may be used as biomarkers of exposure to HHPA and MHHPA.
六氢邻苯二甲酸酐（HHPA）和甲基六氢邻苯二甲酸酐（MHHPA）是化学工业中使用的高致敏性化合物。本研究的目的是表征暴露于HHPA和MHHPA后红细胞中的蛋白质加合物。从51名接触HHPA和MHHPA的工人中采集血液和尿液样本。通过凝胶过滤和离子交换色谱法对接触HHPA和MHHPA的工人的红细胞蛋白进行分离。将氚标记和未标记的HHPA与血红蛋白（Hb）之间的体外合成缀合物用酸水解或用链霉蛋白酶E消化。通过气相色谱 - 质谱法（GC-MS）分析体内形成的酸酐 - Hb加合物水平以及相应酸的尿液/血浆水平，并进行相关性分析。在离职或休假的工人中研究了加合物的衰减情况。在凝胶过滤和离子交换色谱中，体内超过85%形成加合物的蛋白质与Hb共洗脱。通过GC-MS发现，体外形成的加合物中至少70%的HHPA存在于赖氨酸上。使用链霉蛋白酶E消化的氚标记Hb-HHPA也得到了类似的结果。工人中HHPA的加合物水平范围为0 - 26 pmol/g Hb（平均2.7 pmol/g Hb），MHHPA的范围为0 - 55 pmol/g Hb（平均4.1 pmol/g Hb）。尿液数据与加合物之间的Spearman等级相关系数，HHPA为rs = 0.80，MHHPA为rs = 0.78。对于血浆，使用HHPA数据的相关性为rs = 0.80，MHHPA为rs = 0.69。加合物在体内似乎是稳定的。加合物水平可作为接触HHPA和MHHPA的生物标志物。
