Popa-Nita Oana, Marois Louis, Paré Guillaume, Naccache Paul H
Laval University, Quebec, Quebec, Canada.
Arthritis Rheum. 2008 Jun;58(6):1866-76. doi: 10.1002/art.23801.
Monosodium urate monohydrate (MSU) crystals are among the most potent proinflammatory stimuli, and an innate immune inflammatory response to the crystal surface is involved in the pathogenesis of gouty arthritis. Release of the crystals into the joint cavity promotes an acute inflammation characterized by massive infiltration of neutrophils, which leads to tissue damage. The aim of the present study was to assess the involvement of the tyrosine kinase Tec in MSU crystal-initiated transduction events in human neutrophils.
Immunoprecipitation and immunoblotting techniques were used for the cellular signaling studies. Chemotaxis and enzyme-linked immunosorbent assay techniques were used for the functional studies. Silencing of Tec expression using specific small interfering RNA was also performed.
MSU crystals induced the phosphorylation and activation of Tec in a Src-dependent manner. This activation was necessary for the MSU crystal-induced secretion of interleukin-1beta (IL-1beta) and IL-8 and for the generation of chemotactic activity in supernatants of MSU crystal-stimulated neutrophils. In addition, colchicine, an effective drug for the treatment of gout, inhibited the MSU crystal-induced tyrosine phosphorylation of Tec, thus modulating its kinase activity.
Our findings show that Tec is the principal kinase of the Tec family that plays a major role in the responses of human neutrophils to MSU crystals, which are likely to be involved in the initiation and perpetuation of gout. Our results suggest that the specific inhibition of Tec during the acute phase of MSU crystal-induced inflammation may be considered for the treatment of gouty arthritis.
一水合尿酸钠（MSU）晶体是最有效的促炎刺激物之一，对晶体表面的先天性免疫炎症反应参与痛风性关节炎的发病机制。晶体释放到关节腔会引发以中性粒细胞大量浸润为特征的急性炎症，进而导致组织损伤。本研究的目的是评估酪氨酸激酶Tec在人中性粒细胞中MSU晶体引发的转导事件中的作用。
采用免疫沉淀和免疫印迹技术进行细胞信号研究。采用趋化性和酶联免疫吸附测定技术进行功能研究。还使用特异性小干扰RNA沉默Tec表达。
MSU晶体以Src依赖的方式诱导Tec的磷酸化和激活。这种激活对于MSU晶体诱导的白细胞介素-1β（IL-1β）和IL-8分泌以及在MSU晶体刺激的中性粒细胞上清液中产生趋化活性是必需的。此外，秋水仙碱作为治疗痛风的有效药物，可抑制MSU晶体诱导的Tec酪氨酸磷酸化，从而调节其激酶活性。
我们的研究结果表明，Tec是Tec家族的主要激酶，在人中性粒细胞对MSU晶体的反应中起主要作用，这可能参与痛风的起始和持续。我们的结果表明，在MSU晶体诱导的炎症急性期对Tec进行特异性抑制可能被考虑用于治疗痛风性关节炎。
