Kurihara H, Murayama Y, Warbington M L, Champagne C M, Van Dyke T E
Department of Periodontology and Endodontology, Okayama University Dental School, Japan.
Infect Immun. 1993 Aug;61(8):3137-42. doi: 10.1128/iai.61.8.3137-3142.1993.
Protein kinase C is a key molecule in neutrophil signal transduction after receptor stimulation by soluble bioactive molecules. It has been reported that neutrophils from most patients with localized juvenile periodontitis (LJP) do not have a normal response after stimulation with a chemotactic ligand such as N-formylmethionylleucylphenylalanine (FMLP). To further clarify the mechanism of this altered response and to confirm and expand earlier observations, the calcium-dependent protein kinase C activity of neutrophils from patients with LJP was evaluated. Peripheral blood neutrophils from 12 patients and 12 healthy subjects, age, sex, and race matched, were sonicated and subsequently subfractionated by ultracentrifugation into a soluble fraction (cytosol rich) and a particulate fraction (membrane rich). The calcium-dependent protein kinase C activity was evaluated in each fraction by phosphorylation of histone with radiolabeled ATP in the presence or in the absence of phorbol 12-myristate 13-acetate stimulation. Results revealed that the total calcium-dependent protein kinase C activity of neutrophils from patients with LJP and depressed chemotactic migration to FMLP (201.0 +/- 63.6 pmol/min/10(7) cells) was lower than that of neutrophils from healthy subjects (287.6 +/- 55.7 pmol/min/10(7) cells) (P < 0.01). The calcium-dependent protein kinase C activity in neutrophils from patients with LJP exhibited a positive correlation with chemotactic migration to FMLP (P < 0.05). The low activity of calcium-dependent protein kinase C in neutrophils from the patients reflected the low activity in the soluble fraction from the neutrophils. After stimulation with phorbol 12-myristate 13-acetate, the calcium-dependent protein kinase C activity was found to be lower from patients with LJP than from healthy subjects. These results suggest that lower calcium-dependent protein kinase C in neutrophils is a predisposing factor for LJP.
蛋白激酶C是可溶性生物活性分子刺激受体后中性粒细胞信号转导中的关键分子。据报道，大多数局限性青少年牙周炎（LJP）患者的中性粒细胞在用趋化配体如N-甲酰甲硫氨酰亮氨酰苯丙氨酸（FMLP）刺激后没有正常反应。为了进一步阐明这种反应改变的机制，并确认和扩展早期观察结果，对LJP患者中性粒细胞的钙依赖性蛋白激酶C活性进行了评估。对12例患者和12名年龄、性别和种族匹配的健康受试者的外周血中性粒细胞进行超声处理，随后通过超速离心将其亚分级为可溶性部分（富含胞质溶胶）和颗粒部分（富含膜）。在存在或不存在佛波醇12-肉豆蔻酸酯13-乙酸酯刺激的情况下，通过用放射性标记的ATP使组蛋白磷酸化来评估每个部分中的钙依赖性蛋白激酶C活性。结果显示，LJP患者中对FMLP趋化迁移降低的中性粒细胞的总钙依赖性蛋白激酶C活性（201.0±63.6 pmol/分钟/10⁷个细胞）低于健康受试者的中性粒细胞（287.6±55.7 pmol/分钟/10⁷个细胞）（P<0.01）。LJP患者中性粒细胞中的钙依赖性蛋白激酶C活性与对FMLP的趋化迁移呈正相关（P<0.05）。患者中性粒细胞中钙依赖性蛋白激酶C的低活性反映了中性粒细胞可溶性部分中的低活性。在用佛波醇12-肉豆蔻酸酯13-乙酸酯刺激后，发现LJP患者的钙依赖性蛋白激酶C活性低于健康受试者。这些结果表明，中性粒细胞中较低的钙依赖性蛋白激酶C是LJP的一个易感因素。
