Antigen presentation of Type II collagen in rats

Collagen-induced arthritis (CIA) is a T-cell dependent disease of rats which follows immunization with bovine type II collagen (bCII). Susceptibility to CIA is linked to the genes encoding the major histocompatibility complex (MHC), suggesting that antigen presentation is important in disease pathogenesis. Antigen-presenting cells (APC) (macrophages, dendritic cells (DC) and B cells) were prepared from WA/KIR/KCL rats and presentation of antigen, in the form of native protein (bCII) or synthetic peptide (bCII:184-198), was assessed in T-cell proliferation assays. Whilst macrophages inhibited proliferative responses to bCII, splenic or thymic low density cells, enriched for DC, presented both bCII and bCII(184-198) peptide. However, bone marrow-derived DC, which stimulated T-cell responses to OVA, failed to present bCII, suggesting differences in processing of these two antigens. B-cell depletion from lymph node cells abrogated the proliferative response to bCII and reconstitution of a T-cell population with B cells restored the proliferative response, indicating that B cells are important for stimulating T-cell responses to bCII. B cells play a critical role in CIA by producing pathogenic anti-bCII antibodies, and we propose that B cells are also important APC which present bCII to CD4+ T cells.     

氨基葡萄糖胶囊干预膝骨关节炎患者外周血单个核细胞中软骨代谢相关基因的表达

背景:目前关于氨基葡萄糖的研究多集中于对膝骨关节炎的治疗作用,但关于其对膝骨关节炎患者外周血中软骨代谢相关基因影响的研究有限。目的:观察氨基葡萄糖胶囊对膝骨关节炎的治疗效果及对软骨代谢相关基因表达的影响。方法:选取2017年3月至2019年2月郑州大学附属郑州中心医院收治的90例膝骨关节炎患者,另选取同期医院体检中心收入的40例健康受试者,检测并对比健康受试者与膝骨关节炎患者治疗前外周血单个核细胞中软骨寡聚基质蛋白、Ⅱ型胶原纤维α1、聚糖蛋白、特异性组织抑制物3基因表达水平。采用随机数表法将膝骨关节炎患者分为常规组和研究组,分别给予双氯芬酸钠缓释片、双氯芬酸钠缓释片+氨基葡萄糖胶囊治疗12周,对比治疗前后2组外周血单个核细胞中各基因表达水平、Lequesne指数,统计治疗期间2组不良反应发生情况。结果与结论:①与健康受试者比较,膝骨关节炎患者外周血单个核细胞中软骨寡聚基质蛋白、特异性组织抑制物3 mRNA相对表达量升高(P<0.05),Ⅱ型胶原纤维α1、聚糖蛋白mRNA相对表达量降低(P<0.05);②治疗前研究组和常规组外周血单个核细胞中各基因表达水平比较,差异均无显著性意义(P>0.05);治疗后2组外周血单个核细胞中软骨寡聚基质蛋白、特异性组织抑制物3 mRNA相对表达量均低于治疗前,且研究组低于常规组(P<0.05);治疗后2组外周血单个核细胞中Ⅱ型胶原纤维α1、聚糖蛋白mRNA相对表达量均高于治疗前,且研究组高于常规组(P<0.05);③治疗前研究组和常规组Lequesne指数比较,差异均无显著性意义(P>0.05);治疗后2组Lequesne指数均低于治疗前,且研究组低于常规组(P<0.05);④研究组和常规组不良反应发生率比较,差异均无显著性意义(P>0.05);⑤结果表明,氨基葡萄糖胶囊可有效改善膝骨关节炎患者临床症状且安全可靠,可能通过抑制软骨寡聚基质蛋白、特异性组织抑制物3基因表达,促进Ⅱ型胶原纤维α1、聚糖蛋白基因表达实现的。     

Age-related changes in gene expression patterns of matrix metalloproteinases and their collagenous substrates in mandibular condylar cartilage in rats

Matrix metalloproteinases (MMPs) have been implicated in physiological cartilage matrix remodelling as well as in pathological and invasive extracellular matrix remodelling of tissue. Age-related changes in the gene expression patterns of MMPs in mandibular condylar cartilages (MCCs) were analysed. We examined the gene expression patterns of Mmp-8 and -13 and their substrates, Col1a1, Col2a1 and Col10a1, in MCC of growing and ageing rats. Temporomandibular joints of male Wistar rats aged 4, 8, 16 and 32 weeks were subjected to in situ hybridization analysis. Histologically, MMCs showed characteristics of growth plate cartilage at ages 4 and 8 weeks, and more closely resembled articular cartilage thereafter. Mmp-8 was expressed in the cells in all cartilaginous cell layers at ages 4 and 8 weeks, and then was localized only in the mature cells at ages 16 and 32 weeks. Whereas Mmp-13 expression was limited to the lowermost hypertrophic chondrocytes in the growth stage, mature chondrocytes instead of hypertrophic chondrocytes expressed Mmp-13 in adult non-hypertrophic MCC. Because Mmp-8 and -13 expression overlapped with Col2a1 and Col10a1, chondrocytes could play a pivotal role in degradation as well as production of the cartilaginous matrix in MCC.     

大鼠肝内移植肿瘤与肥大细胞关系的形态学研究

目的：研究大鼠肝内移植肿瘤与其周边肥大细胞的关系。方法：建立40只雄性Wistar大鼠肝内移植肿瘤模型，运用HE染色，肥大细胞（mast cell，MC）Alcian blue特殊染色，苦味酸-天狼猩红染色和电镜等技术，观察移植肿瘤肝组织的形态学改变，肿瘤周边浸润MC的数量以及MC与肿瘤组织的关系，8只正常大鼠为对照组。结果：肿瘤组织周边部分肝细胞形态学异常；肝组织内胶原纤维增生，主要为Ⅰ型和Ⅲ型胶原，并包绕肿瘤组织，肿瘤周边MC浸润，并沿胶原纤维分布，不同大鼠其肿瘤周边MC数量不一，有的差异明显。超微结构观察显示MC通过多个接触点与肿瘤细胞紧密相连，并释放胞质颗粒内容物，导致肿瘤细胞崩解。结论：MC与肿瘤组织有着非常密切的关系，MC可能通过多种途径直接和间接地发挥抗肿瘤作用。     

通痹灵对于IL-2及其受体α链影响的体内外研究

从体内体外两个方面 ,研究通痹灵对于CIA大鼠关节滑膜原代细胞分泌IL 2 ,以及通痹灵总碱对于IL 2受体α链CD2 5表达的影响。体内实验采用CIA大鼠动物模型。容积法测量足肿胀度 ,原代滑膜细胞培养、放免法检测培养液上清 ,观察通痹灵对滑膜内IL 2的影响 ;体外实验 ,分离大鼠淋巴细胞 ,佛波醇酯 (PDB )或刀豆蛋白 (ConA )体外刺激 ,双色免疫荧光标记 ,流式细胞仪检测 ,观察通痹灵总碱对CD3+CD2 5 +表达的影响。结果是体内实验 ,通痹灵高剂量可明显减轻CIA大鼠的足肿胀度 ,与MTX比较无显著性差异 (P >0 0 5 ) ,通痹灵高、低剂量可明显抑制CIA大鼠滑膜内IL 2的合成 (P <0 0 1) ;体外实验 ,通痹灵总碱显著抑制ConA刺激下的CD3+CD2 5 +的表达 ,而对PDB加ionomycin没有明显作用。提示通痹灵可以通过抑制IL 2合成及ConA激活的IL 2受体α链CD2 5信号转导通路 ,减轻局部关节的炎症 ,为其用于类风湿性关节炎的治疗提供了实验依据     

Vestibular and audiological findings in the Alport syndrome

Alport syndrome (AS) is caused by mutations in collagen IV, which is widespread in the basement membranes of many organs, including the kidneys, eyes, and ears. Whereas the effects of collagen IV changes in the cochlea are well known, no changes have been described in the posterior labyrinth. The aim of this study was to investigate both the auditory and the vestibular function of a group of individuals with AS. Seventeen patients, aged 9–52, underwent audiological tests including pure‐tone and speech audiometry, immittance test and otoacoustic emissions and vestibular tests including video head impulse test, rotatory test, and vestibular evoked myogenic potentials. Hearing loss affected 25% of the males and 27.3% of the females with X‐linked AS. It was sensorineural with a cochlear localization and a variable severity. 50% of the males and 45.4% of the females had a hearing impairment in the high‐frequency range. Otoacoustic emissions were absent in about one‐third of the individuals. A peripheral vestibular dysfunction was present in 75% of the males and 45.4% of the females, with no complaints of vertigo or dizziness. The vestibular impairment was compensated and the vestibulo‐ocular reflex asymmetry was more evident in rotatory tests carried out at lower than higher speeds; a vestibular hypofunction was present in all hearing impaired ears although it was also found in subjects with normal hearing. A posterior labyrinth injury should be hypothesized in AS even when the patient does not manifest hearing disorders or evident signs of renal failure.     

mTOR signaling contributes to chondrocyte differentiation.

The mammalian Target Of Rapamycin (mTOR) is a nutrient-sensing protein kinase that regulates numerous cellular processes. Fetal rat metatarsal explants were used as a physiological model to study the effect of mTOR inhibition on chondrogenesis. Insulin significantly enhanced their growth. Rapamycin significantly diminished this response to insulin through a selective effect on the hypertrophic zone. Cell proliferation (bromodeoxyuridine incorporation) was unaffected by rapamycin. Similar observations were made when rapamycin was injected to embryonic day (E) 19 fetal rats in situ. In the ATDC5 chondrogenic cell line, rapamycin inhibited proteoglycan accumulation and collagen X expression. Rapamycin decreased content of Indian Hedgehog (Ihh), a regulator of chondrocyte differentiation. Addition of Ihh to culture medium reversed the effect of rapamycin. We conclude that modulation of mTOR signaling contributes to chondrocyte differentiation, perhaps through its ability to regulate Ihh. Our findings support the hypothesis that nutrients, acting through mTOR, directly influence chondrocyte differentiation and long bone growth.