肺结核患者痰和血浆IFN-γ含量检测的临床意义探讨

目的探讨肺结核患者痰和血浆中γ-干扰素（interferon-gamma,IFN-γ）水平在结核病诊断、鉴别诊断中的意义。方法用酶联免疫吸附剂测定法（ELISA）分别检测44例活动性肺结核患者（PTB）、36例正常对照者、18例肺癌患者痰和血浆中IFN-γ含量。结果结核分枝杆菌潜伏感染者（LTBI）痰和血浆IFN-γ含量与健康人相接近（P〉0.05）;肺结核患者血浆IFN-γ含量显著高于正常对照及肺癌患者（P值均〈0.05）,肺结核患者痰中IFN-γ含量显著低于正常对照及肺癌患者（P值均〈0.01）;肺结核患者痰IFN-γ含量低于血浆IFN-γ含量;痰及血浆中IFN-γ的ROC曲线下面积（AUC）分别为0.90和0.91,当痰中IFN-γ诊断临界值为21.40 pg/ml时,敏感度85.71%、特异性82.35%;当血浆IFN-γ诊断临界值为27.91 pg/ml时,敏感度71.43%、特异性94.12%。结论痰和/或血浆中IFN-γ可以作为肺结核诊断（尤其是菌阴肺结核）、鉴别诊断的重要辅助指标之一。     

Bioassay-guided fractionation of a thymol-deprived hydrophilic thyme extract and its antispasmodic effect

Ethnopharmacological relevance

Extracts from Thymus vulgaris L. and Thymus zygis L. are traditionally used for bronchitis, catarrhs of the respiratory tract and supportive treatment of pertussis. A potential spasmolytic effect is thought to be due to the presence of the monoterpenoid phenols thymol and carvacrol in the extract. Based on previous data the present investigation aimed to clarify if thymol-deprived thyme extracts (as been in use within German drug market) have antispasmodic activity. Additionally compounds responsible for this effect had to be identified.

Materials and methods

Thyme fluid extract was subsequently fractionated by FCPC, LPLC, and HPLC and compounds isolated were identified by spectroscopic methods. Bioassay testing was done by quantification of antispasmodic activity in the preconstricted rat smooth muscle trachea model against papaverin as positive control.

Results

Thymol-deprived spissum extract (SE) had good antispasmodic activity (−37%, related to the maximum contraction). Bioassay-guided fractionation indicated that rosmarinic acid and apigenin do not contribute to this effect. Luteolin contributed significantly to the antispasmodic activity (−9%).

Conclusions

Thyme extracts have antispasmodic activity, which is at least due to synergistic effects of phenolic volatile oil compounds and the flavone luteolin. Specifications of thyme-containing preparations should refer to this flavone in addition to focusing on the volatile phenols.     

Cytokine profile after oral food challenge in infants with food protein-induced enterocolitis syndrome

BackgroundAlthough food protein-induced enterocolitis syndrome (FPIES) is supposed to be caused by inflammation, the role of cytokines has not yet been clarified.MethodsTo elucidate the role of cytokines in the development of symptoms and abnormal laboratory findings at an oral food challenge (OFC), changes in serum cytokine levels were analyzed for 6 OFCs in 4 patients with FPIES. The result of OFC was judged positive if any gastrointestinal (GI) symptoms (vomiting, diarrhea, or bloody stool) were induced.ResultsAmong 11 cytokines profiled, serum levels of interleukin (IL)-2, IL-5, and IL-8 were clearly increased in all 4 positive OFCs in which elevations of the serum level of C-reactive protein (CRP) and peripheral blood neutrophilia were also seen. The level of serum IL-10 also rose in 2 positive OFCs. Remarkable increases in the serum level of interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), IL-6, and IL-12 were observed in a positive OFC where the serum level of CRP rose markedly (6.75 mg/dL). The serum levels of IL-5 were also elevated in 2 negative OFCs. No apparent specific correlations were found between cytokines and GI symptoms.ConclusionsThese results suggest that IL-2 and IL-8 are involved in the antigen-specific immune responses in most patients with FPIES. Further studies are needed to elucidate the significance of these cytokine in the pathogenesis of FPIES.     

Mast cells in psoriatic skin are strongly positive for interferon-gamma

The increased number and early activation of cutaneous mast cells is a typical feature of psoriatic inflammation. Interferon-gamma (IFN-gamma) is believed to be one of the important mediators in the cytokine cascade of psoriasis. Human mast cells have been previously reported to release various cytokines upon stimulation including interleukin (IL) -4, IL-5, IL-6, IL-8, IL-13 and tumour necrosis factor-alpha. Here we report that human mast cells synthesize also IFN-gamma at mRNA and protein level and that the number of IFN-gamma producing mast cells is significantly increased in the psoriatic skin. IFN-gamma immunoreactivity in mast cells was demonstrated by staining non-lesional and lesional skin sections from 21 patients with psoriasis. Ten patients with atopic dermatitis (AD) and five healthy persons served as control groups. The percentage (mean +/- SD) of IFN-gamma + mast cells in lesional compared with non-lesional psoriatic skin was 67 +/- 18% vs. 44 +/- 17% (P < 0.0001, paired t-test), respectively, but only 9 +/- 6% vs. 10 +/- 7% in corresponding skin samples of AD. In the skin of healthy controls, only 12 +/- 12% of the mast cells were IFN-gamma +. Using immunoelectron microscopy, we confirmed the ultrastructural localization of IFN-gamma within the granules of mast cells in psoriatic skin. In addition, stimulation of a human mast cell line HMC-1 with phorbol myristate acetate (PMA) (100 nmol/L) for periods of 2-24 h induced expression of IFN-gamma mRNA, which peaked at 24 h. When HMC-1 cells were stimulated with PMA (100 nmol/L) for periods of 0-3 days, the cells released IFN-gamma protein, peaking on day 1. These results provide further evidence for the important role of mast cells in the pathogenesis of psoriasis.     

3种检测方法在儿童活动性结核病诊断中的应用

目的评价γ-干扰素释放试验(IGRA)、结核菌素皮肤试验(TST)及结核抗体(TB-Ab)检测对儿童活动性结核病的临床诊断价值,并分析IGRA及TST在不同年龄患儿中的应用价值。方法收集该院就诊的疑似结核患儿367例资料,其中临床诊断结核病患儿113例,非结核病患儿254例。分析3种方法的灵敏度、特异度、一致性及受试者工作特征曲线下面积(AUC)等。根据年龄将患儿分为不同亚组(0~<2岁组、2~<6岁组、6~<10岁组、10~15岁组),分析IGRA及TST在各组中的参数。结果IGRA的灵敏度(90.1%)高于TST(77.9%)及TB-Ab检测(7.9%);TB-Ab检测的特异度(98.6%)高于IGRA(91.7%)及TST(83.5%)。IGRA与临床诊断结果具有较高的一致性,其次为TST、TB-Ab检测(Kappa值分别为0.800、0.598、0.087)。IGRA准确度最高,其次为TST、TB-Ab检测,AUC分别为0.910、0.807及0.533。4个年龄组间IGRA(Kappa值分别为0.784、0.867、0.744、0.770)与临床诊断结果一致性均高于TST(Kappa值分别为0.459、0.548、0.736、0.567)。6~<10岁组IGRA结果与临床诊断结果比较,差异有统计学意义(P<0.05);0~<2岁组TST结果与临床诊断结果比较,差异有统计学意义(P<0.05)。结论IGRA对儿童活动性结核病的检测价值较高,TB-Ab检测诊断价值较低;联合使用IGRA及TST可以更好地提高各年龄段儿童结核病的诊断效率。     

Interferon-gamma release assays in tuberculous uveitis: a comprehensive review

Tuberculous uveitis (TBU) comprises a broad clinical spectrum of ocular manifestations, making its diagnosis challenging. Ophthalmologists usually require evidence from investigations to confirm or support a clinical diagnosis of TBU. Since direct isolation of the causative organism from ocular specimens has limitations owing to the small volume of the ocular specimens, resultant test positivities are low in yield. Immunodiagnostic tests, including the tuberculin skin test and interferon-gamma release assays (IGRAs), can help support a clinical diagnosis of TBU. Unlike the tuberculin skin test, IGRAs are in vitro tests that require a single visit and are not affected by prior Bacillus Calmette-Guerin vaccination. Currently, available IGRAs consist of different techniques and interpretation methods. Moreover, newer generations have been developed to improve the sensitivity and ability to detect active tuberculosis. This narrative review collates salient practice points as a reference for general ophthalmologists, such as evidence for the utilization of IGRAs in patients with suspected TBU, and summarizes basic knowledge and details of clinical applications of these tests in a clinical setting.     

呼吸道合胞病毒感染促进哮喘小鼠气道分泌TSLP和Th2炎症反应

目的 探讨呼吸道合胞病毒(RSV)对哮喘小鼠胸腺基质淋巴细胞生成素(TSLP)分泌的影响,以探索RSV对哮喘小鼠Th1/Th2免疫反应的调节作用.方法 雌性BALB/c小鼠32只.随机分成4组,分别为磷酸盐缓冲液(PBS)对照组、鸡卵白蛋白(OVA)组、RSV组、OVA/RSV组;应用OVA腹腔注射致敏、OVA气道雾化结合RSV滴鼻激发哮喘;无创肺功能检测小鼠气道反应性,ELISA法检测小鼠血清IL-4、IFN-γ、IL-5、IL-13水平;ELISA法检测气管灌洗液(BALF)TSLP含量并进行细胞分类计数;小鼠肺组织病理观察炎症反应,免疫组化观察小鼠气管上皮细胞TSLP表达水平.结果 RSV感染促进哮喘小鼠呼吸道分泌TSLP增加,OVA/RSV组小鼠TSLP浓度达(2.13±0.05)ng/ml,高于其他组(P<0.01);同时促进IL-4、IL-5、IL-13等Th2型细胞因子的分泌,并增加IFN-γ分泌;0VA/RSV组BALF细胞总数、嗜酸性粒细胞数、中性粒细胞数、淋巴细胞数与其他各组比较均明显增加;无创肺功能检测显示OVA/RSV组小鼠气道反应性明显增高,乙酰甲胆碱浓度达6.25 mg/ml时,Penh值(318.66±50.87)明显增加,与其他各组比较具有统计学意义(P<0.01);病理观察显示RSV感染明显加重哮喘小鼠气道炎症细胞浸润;免疫组化染色证实RSV/OVA组小鼠气道上皮细胞TSLP表达量较高.结论 RSV感染可以增加小鼠气道上皮细胞表达TSLP,促进Th2细胞因子的表达,加重哮喘小鼠肺部Th2炎症反应.     

抗奶牛γ-干扰素特异性单克隆抗体的研制及其特性

利用IPTG诱导大肠杆菌表达牛-γ干扰素融合蛋白(GST-BovIFN-γ),经聚丙烯酰胺凝胶电泳(SDS-PAGE)后,切取融合蛋白条带作为抗原免疫BALB/c小鼠。利用杂交瘤技术研制抗牛-γ干扰素(BovIFN-γ)的特异性单克隆抗体(mAb)。采用间接酶联免疫吸附试验(ELISA)方法筛选、Western-blotting、间接免疫荧光(IFA)方法进行鉴定,筛选出2株分泌特异性抗BovIFN-γ的杂交瘤细胞株,分别命名为BovIFN--γ4A3和BovIFN--γ4G5。该单抗可以与重组GST-BovIFN-γ和真核细胞表达的rBovIFN-γ反应,但不能与GST和鸡IFN-γ反应,说明单抗具有很好的特异性。进一步研究表明单抗能中和BovIFN-γ对水泡性口炎病毒(VSV)对牛肾细胞的致病变作用。这些单抗可用于奶牛结核病的监测和防治。