Tudan C, Fong D, Duronio V, Burt H M, Jackson J K
Faculty of Pharmaceutical Sciences and the Department of Medicine, University of British Columbia, Vancouver, Canada.
J Rheumatol. 2000 Oct;27(10):2463-72.
Spontaneous neutrophil apoptosis may be inhibited by various proinflammatory stimuli. which may result in prolonged lifetimes and responses of these phagocytic cells with the potential for extended inflammation. We investigated the effect of short term incubation of opsonized crystals of monosodium urate monohydrate (MSUM) or calcium pyrophosphate dihydrate (CPPD) on both spontaneous and tumor necrosis factor-alpha (TNF-alpha) induced neutrophil apoptosis.
Peripheral neutrophils were incubated with plasma opsonized crystals of CPPD or MSUM in the presence or absence of TNF-alpha for 4 h at 37 degrees C. Apoptosis was determined using 3 separate assays: (1) an agarose DNA fragmentation assay, (2) a cytoplasmic histone associated DNA fragmentation assay, and (3) a caspase 3 fluorometric assay.
All 3 assays showed similar results. Both MSUM and CPPD crystals inhibited spontaneous apoptosis in neutrophils. TNF-alpha induced high levels of apoptosis in neutrophils. However, co-incubation of the cells with TNF-alpha and crystals resulted in the inhibition of apoptosis to levels below those of control cells. Pretreatment of neutrophils with the protein synthesis inhibitor cycloheximide prevented the inhibition of apoptosis by crystals.
These data support the concept of crystal induced inhibition of neutrophil apoptosis as part of the pathophysiology of the diseases collectively known as crystal induced arthritis.
多种促炎刺激可能抑制中性粒细胞的自发凋亡，这可能导致这些吞噬细胞寿命延长和反应增强，进而引发炎症持续。我们研究了短期孵育尿酸单钠（MSUM）或二水焦磷酸钙（CPPD）调理晶体对自发及肿瘤坏死因子-α（TNF-α）诱导的中性粒细胞凋亡的影响。
将外周血中性粒细胞与CPPD或MSUM的血浆调理晶体在有或无TNF-α的情况下于37℃孵育4小时。使用3种不同的检测方法测定凋亡：（1）琼脂糖DNA片段化检测，（2）细胞质组蛋白相关DNA片段化检测，（3）半胱天冬酶3荧光检测。
所有3种检测方法显示出相似的结果。MSUM和CPPD晶体均抑制中性粒细胞的自发凋亡。TNF-α诱导中性粒细胞高水平凋亡。然而，细胞与TNF-α和晶体共同孵育导致凋亡抑制至低于对照细胞的水平。用蛋白质合成抑制剂环己酰亚胺预处理中性粒细胞可防止晶体对凋亡的抑制。
这些数据支持晶体诱导中性粒细胞凋亡抑制这一概念，它是统称为晶体诱导性关节炎的疾病病理生理学的一部分。
