Feola R P, Collins M T, Czuprynski C J
Department of Pathobiological Sciences, University of Wisconsin, Madison, WI, 53706, USA.
Microb Pathog. 1999 Jan;26(1):1-11. doi: 10.1006/mpat.1998.0246.
In this study, we evaluated the effects of several hormones (i.e. growth hormone, prolactin, vitamin D3, luteinizing hormone, oxytocin) on the phagocytosis and intracellular survival of Mycobacterium avium ss. paratuberculosis within bovine peripheral blood monocytes. Phagocytosis of M. avium ss. paratuberculosis declined in a dose-dependent manner when monocytes were exposed to increasing amounts of recombinant bovine growth hormone, with little phagocytosis occurring at a growth hormone concentration of 50 ng/ml. The other hormones tested had little effect on phagocytosis. Continuous exposure of bovine monocytes to bovine growth hormone (10 ng per ml) resulted in enhanced intracellular bacillary growth. This was detected within 3 days of monocyte infection, and resulted in a 1 Log10 greater number of M. avium ss. paratuberculosis in growth hormone treated, than control, monocytes at 12 days of infection. When monocytes were incubated with growth hormone for only the first 5 days of a 12 day incubation period, a further increase in bacillary multiplication was observed. A similar increase in bacillary multiplication was observed when M. avium ss. paratuberculosis monocytes were incubated with prolactin for the first 5 days of a 12 day incubation period. These data indicate that varying levels of growth hormone and prolactin can affect the intracellular multiplication of M. avium ss. paratuberculosis in bovine monocytes.
在本研究中，我们评估了几种激素（即生长激素、催乳素、维生素D3、促黄体生成素、催产素）对牛外周血单核细胞内鸟分枝杆菌副结核亚种吞噬作用和细胞内存活的影响。当单核细胞暴露于越来越多的重组牛生长激素时，鸟分枝杆菌副结核亚种的吞噬作用呈剂量依赖性下降，在生长激素浓度为50 ng/ml时几乎没有吞噬作用发生。所测试的其他激素对吞噬作用影响很小。牛单核细胞持续暴露于牛生长激素（每毫升10 ng）导致细胞内细菌生长增强。这在单核细胞感染后3天内即可检测到，并且在感染12天时，生长激素处理的单核细胞中鸟分枝杆菌副结核亚种的数量比对照单核细胞多1个对数级。当单核细胞仅在12天培养期的前5天与生长激素一起孵育时，观察到细菌增殖进一步增加。当鸟分枝杆菌副结核亚种单核细胞在12天培养期的前5天与催乳素一起孵育时，也观察到类似的细菌增殖增加。这些数据表明，不同水平的生长激素和催乳素会影响牛单核细胞内鸟分枝杆菌副结核亚种的细胞内增殖。
