Thuvander A, Dahl P, Breitholtz-Emanuelsson A
Toxicology Division, Swedish National Food Administration, Sweden.
Nat Toxins. 1996;4(4):174-80. doi: 10.1002/19960404nt5.
The mycotoxin ochratoxin A (OA) is a well-documented immunotoxic agent which affects both cellular and humoral immunity. In the present study, the effects of maternal exposure to single doses of OA during gestation or lactation were studied in Balb/c offspring. A single dose exposure of the dams to OA (500 micrograms/kg body weight) on day 16 of gestation resulted in decreased proliferation of splenic and thymic lymphocytes in response to mitogens in the pups at 15 days of age. Flow cytometry analysis of thymocyte subpopulations revealed lower percentages of mature CD4+ cells and higher percentages of immature, double-positive (CD4+CD8+) cells in the exposed pups. In contrast, a single exposure of the dams of OA on day 10 postpartum significantly increased the proliferative responsiveness of lymphocytes in the offspring when stimulated with B or T cell mitogens 3 days after the exposure. This effect was most prominent in the highest dose group (500 micrograms/kg body weight). The present results are in accordance with previous observations in rats, and show that the time of exposure significantly influences the immunotoxic effects of OA on the developing immune system in rodents.
霉菌毒素赭曲霉毒素A（OA）是一种有充分文献记载的免疫毒性剂，会影响细胞免疫和体液免疫。在本研究中，我们对Balb/c后代中母鼠在妊娠期或哺乳期单次接触OA的影响进行了研究。在妊娠第16天给母鼠单次注射OA（500微克/千克体重），导致15日龄幼崽的脾淋巴细胞和胸腺淋巴细胞对有丝分裂原的增殖反应降低。对胸腺细胞亚群的流式细胞术分析显示，暴露组幼崽中成熟CD4+细胞的百分比降低，未成熟双阳性（CD4+CD8+）细胞的百分比升高。相比之下，产后第10天给母鼠单次注射OA，在接触3天后用B或T细胞有丝分裂原刺激时，后代淋巴细胞的增殖反应显著增加。这种效应在最高剂量组（500微克/千克体重）最为明显。本研究结果与先前在大鼠中的观察结果一致，表明接触时间显著影响OA对啮齿动物发育中免疫系统的免疫毒性作用。
