Tamm—Horsfall蛋白糖基组分的致肾炎作用

我们在体外试验中证实：Ｔａｍｍ－Ｈｏｒｓｆａｌｌ蛋（ＴＨＰ）刺激人单核细胞产生肿瘤坏死因子和ＩＬ－１的作用依赖其糖基组分的完整。为了探讨糖基组分在ＴＨＰ所致肾小管间质肾炎（ＴＩＮ）发病机制中的作用，我们给Ｗｉｓｔａｒ大鼠肾内直接注射ＴＨＰ制成ＴＩＮ模型。该模型在发病第４ｄ即有明显的肾间质巨噬细胞（ＭФ）浸润。用高碘酸氧化去除ＴＨＰ的糖基组分明显破坏了ＴＨＰ诱发ＴＩＮ的能力。注射去糖基ＴＨＰ的动物只     

兔肾小管基底膜所致Wistar大鼠肾小管间质性肾炎模型的建立及环磷酰胺对其防治作用

选用兔肾小管基底膜（ＴＢＭ）、完全福氏佐剂及百白破疫苗免疫雌性Ｗｉｓｔａｒ大鼠，成功地建立了肾小管间质性肾炎（ＴＩＮ）模型。实验证明在ＴＩＮ发生时，ＴＢＭ上有ＩｇＧ和Ｃ３沉积，肾间质大量单个核细胞浸润，主要是淋巴细胞，部分有肉芽肿形成。随后出现肾小管萎缩和肾间质纤维化。用环磷酰胺可以抑制ＴＩＮ的发生和进展，其作用机制可能是抑制细胞免疫反应     

单核因子在Tamm—Horsfall蛋白所致肾小管间质肾炎纤维化形…

将Ｗｉｓｔａｒ大鼠的腹腔巨噬细胞（Ｍφ）分别与Ｔａｍｍ－Ｈｏｒｓｆａｌｌ蛋白（ＴＨＰ，Ａ组）、去糖基ＴＨＰ（Ｂ组）或ＲＰＭＩ１６４０（Ｃ组）在体外共育４小时，而后更换接培养液继续孵育２４小时。用生物学方法测定发现唯Ａ组Ｍφ上清液含肿瘤坏死因子和ＩＬ－１样活性。将三组Ｍφ上清液分别注入各自大鼠右肾，６周后Ａ组右肾全部发生了炎症和纤维化，伴有肾小管功能改变，而Ｂ、Ｃ组肾间质无明显异常。由此表明，ＴＨＰ     

兔肾小管基底膜所致Wistar大鼠肾小管间质性肾炎模型的建…

选用兔肾小管基底膜，完全福氏佐剂及百日破疫苗免疫雌性Ｗｉｓｔａｒ大鼠，成功地建立了肾小管间质性肾炎模型。实验证明在ＴＩＮ发生时，ＴＢＭ上有ＩｇＧ和Ｃ３沉积，肾间质大量单个核细胞浸润，主要是淋巴细胞，部分有肉芽肿形成。随后出现肾小管萎缩和肾间质纤维化。用环磷酰胺可以抑制ＴＩＮ的发生和进展，其作用机制可能是抑制细胞免疫反应。     

小管间质肌成纤维细胞激活对大鼠残余肾硬化的影响

目的：本文研究５／６肾大部切除大鼠肾小管间质肌成纤维细胞（ｍｙｏｆｉｂｒｏｂｌａｓｔ，ＭＦＢ）标记性抗原，α－平滑肌肌动蛋白（α－ｓｍｏｏｔｈ ｍｕｓｃｌｅ ａｃｔｉｎ，α－ＳＭＡ）免疫组化表达及其意义。方法：成年雄性Ｗｉｓｔａｒ大鼠（６－８周龄，２００－２５０ｇ）随机分成两组：１．假手术（ｓｈａｍ，ｎ＝５）ｍ，；２，ＳＸｎ 组（ｎ＝５）。     

大鼠肾小球巨噬细胞产生白细胞介素－1及氧自由基在肾小球损伤发生中的作用

本文用大鼠加速肾毒血清肾炎模型，于注射肾毒血清后７２ｈ，用电子自旋共振（ＥＳＫ）和胸腺细胞增殖检测肾炎鼠的肾小球巨噬细胞（ＧＭφ），自身腹腔Ｍφ（ＰＭφ）及正常鼠腹腔Ｍφ（Ｎ－ＰＭφ）所产生羟自由基（ＯＨ）和ＩＬ－１活性。同时观察ＩＬ－１对ＧＭφ、ＰＭφ和Ｎ－ＰＭφ产生ＯＨ的影响。结果显示：肾炎鼠ＧＭφＩＬ－１活性和ｂＨ明显高于ＰＭφ和Ｎ－ＰＭφ；ＩＬ－１能刺激Ｍφ产生ＯＨ，且炎症ＧＭφ的ＯＨ明显高于ＰＭφ和Ｎ－ＰＭφ，揭示：肾小球中浸润的Ｍφ过度活化并产生大量ＩＬ－１及ＯＨ，ＩＬ－１又能进一步刺激Ｍφ产生更多的ＯＨ，这一肾小球内的局部恶性循环，在加速肾毒血清肾损伤的发病机制中可能起着重要作用。     

化瘀导滞汤防治庆大霉素诱导的大鼠肾纤维化

目的： 探讨化瘀导滞汤对庆大霉素所致的肾间质纤维化的影响及作用机制。方法: 32只健康雄性Wistar大鼠随机分为3组：正常组（6只）、肾纤维化模型组（13只）、化瘀导滞汤治疗组（13只）。肾纤维化模型组和化瘀导滞汤治疗组给予庆大霉素造成肾纤维化,造模同时,治疗组给予化瘀导滞汤煎剂灌胃干预,直至取材。于造模后30 d取材,光镜下观察肾组织形态学改变,计算肾系数、检测血肌酐、血尿素氮、24 h尿蛋白总量,检测各组大鼠肾组织α－平滑肌肌动蛋白（α-SMA）、Smad通路蛋白2（Smad2）、Smad通路蛋白7（Smad7）的表达水平。结果: 肾纤维化模型组大鼠与正常组比较,光镜下可见肾小管上皮细胞以坏死为主,部分变性,肾小管萎缩和扩张,间质中有成纤维细胞增生和炎症细胞浸润,间质明显增宽。模型组肾系数、血肌酐、血尿素氮、24 h尿蛋白总量明显高于正常组（P<0.01）,α-SMA、Smad2蛋白表达明显高于正常组（P<0.01）,Smad7蛋白表达明显低于正常组（P<0.01）;化瘀导滞汤治疗组与肾纤维化模型组比较,光镜下肾小管结构有明显改善,治疗组肾系数、血肌酐、血尿素氮、24 h尿蛋白总量与模型组比较有显著下降（P<0.01）,治疗组α-SMA、Smad2蛋白表达明显低于模型组（P<0.01）,Smad7蛋白表达无明显变化（P>0.05）。结论: 化瘀导滞汤有良好的防治庆大霉素诱导的肾纤维化作用。     

厄贝沙坦对肾硬化大鼠肾小管间质中MMP-9/TIMP-1表达的影响

为探讨基质金属蛋白酶9（MMP－9）及其抑制剂（TIMP－1）在单侧肾切除后，重复注射阿霉素复制肾小球硬化大鼠肾小管－间质的表达，以及厄贝沙坦对其的影响和可能的保护作用机制。将肾小球硬化大鼠分为厄贝沙坦治疗组和对照组，设假手术组为正常对照。检测厄贝沙坦治疗4周后，肾功能和病理改变，并用免疫组化或原位杂交的方法分别检测肾小球和肾小管－间质中MMP－9／TIMP－1，转化生长因子β1（TGF－β1）的表达。结果表明肾小球硬化组肾小管中MMP－9，TIMP－1，TGF－β1显著增加。厄贝沙坦组中肾小管中上述指标表达下降。提示厄贝沙坦在延缓肾小球硬化同时，在减轻肾小管－间质纤维化方面有一定保护作用。     

内皮素抗体在大鼠肾缺血/再灌注损伤中的作用

目的和方法：为探讨内皮素在肾缺血／再灌注损伤中的发病学意义，本实验在大鼠肾缺血／再灌注损伤模型上，观察了内皮素抗体对肾缺血／再灌注损伤的作用。结果：肾缺血／再灌注损伤大鼠，血清尿素氮（ＳＵＮ）、肌酐（ＳＣｒ）含量及血浆内皮素（ＰＥＴ）水平显著升高；脂质过氧化物丙二醛（ＭＤＡ）产生增多；肾小管上皮细胞明显损伤。应用内皮素单克隆抗体能显著降低ＰＥＴ水平和ＭＤＡ含量，减轻肾小管上皮细胞损伤，改善肾功能。结论：内皮素是参与肾缺血／再灌注损伤发病的重要因素之一，阻断ＥＴ的生物学作用是防治肾缺血／再灌注损伤的有效途径。     

雷公藤多苷对单侧输尿管结扎小鼠肾小管间质纤维化和炎性损伤的影响

目的通过雷公藤多苷对UUO小鼠肾组织α-平滑肌肌动蛋白（α-smooth muscle actin,α-SMA）、细胞间黏附分子（Intercellular adhesion molecule1,ICAM-1）、单核细胞趋化因子（Monocyte chem oattractant protein1,MCP-1）表达的影响,探讨其防治肾间质纤维化作用及其机理。方法采用小鼠单侧输尿管结扎（UUO）模型,用雷公藤多苷进行干预,用血管紧张素受体抑制剂蒙诺作为对照。肾脏病理用HE和MASSON染色;肾组织α-SMA表达采用免疫组化;ICAM-1蛋白质表达采用Western blot方法检测;MCP-1基因表达采用逆转录-聚合酶链式反应（RT-PCR）方法。结果UUO模型组小鼠肾间质纤维化程度以及肾组织α-SMA的表达较假手术组显著增高,肾小管间质中炎细胞浸润亦较假手术组明显增加;雷公藤多苷各治疗组肾间质纤维化程度、α-SMA和ICAM-1蛋白、MCP-1基因表达均显著低于模型组;蒙诺治疗亦可显著降低肾间质纤维化程度和肾组织α-SMA的表达,但对于炎细胞浸润和炎症因子的抑制作用不如雷公藤多苷显著,而且未见其抑制ICAM-1表达的作用。结论雷公藤多苷可显著抑制肾间质纤维化和肌成纤维细胞的积聚,其机制可能与其抑制肾组织炎症因子的表达及炎细胞浸润有关。     

Release of gelatinase and superoxide from human mononuclear phagocytes in response to particulate Tamm Horsfall protein.

This study describes the in vitro activation of human mononuclear phagocytes by particulate Tamm Horsfall protein (THP). Peripheral blood monocytes phagocytosed THP particles with the accompanying release of superoxide radicals, N-acetyl-beta-D-glucosaminidase, and neutral metalloproteinase. Immunoprecipitation and substrate gel analysis identified the neutral proteinase as a 95-kd gelatinase. A comparison with other particulate ligands highlighted the specificity of the response to THP and showed that the magnitude of the response was comparable with that obtained with lipopolysaccharide (100 micrograms/ml). Parallel studies using peritoneal macrophages resulted in a similar pattern of enzyme release and reactive oxygen species synthesis. THP has been implicated in the pathogenesis of tubulointerstitial nephritis associated with reflux nephropathy. The present study indicates that an inflammatory response initiated by a neutrophil-THP interaction may be extended into a chronic phase via the activation of mononuclear phagocytes. The subsequent release of reactive oxygen metabolites and proteinases may contribute to the tissue damage and fibrosis associated with chronic immune-mediated tubulointerstitial nephritis.     

Pathogenesis of endometritis and salpingitis in a guinea pig model of chlamydial genital infection.

The development of tubal obstruction and subsequent infertility is a major sequelum of upper genital tract infection with Chlamydia trachomatis; however, little is known about the pathogenesis of the infection. In this investigation, the authors present a detailed study of the progression of ascending chlamydial infection in female guinea pigs resulting from intravaginal inoculation of the Chlamydia psittaci agent of guinea pig inclusion conjunctivitis (GPIC). Isolation of chlamydiae from different tissues of the genital tract revealed definitive evidence for ascending infection that was not dose-related. By 7 days after infection, GPIC was isolated from the endometrium and oviducts of 78% of the animals. Pathologic changes analogous to those seen in human chlamydial disease, including polymorphonuclear, mononuclear, and plasma cell infiltration, were seen in the endometrium and oviducts, although not all isolation positive animals developed overt tubal disease. Long-term fibrosis, often in combination with hydrosalpinx, was noted in the mesosalpingeal tissue in 20% of the animals. Thus, the guinea pig:GPIC system represents a model for ascending chlamydial infection resulting from vaginal inoculation of normal guinea pigs that closely approximates the disease as seen in humans and can be used to study the pathogenesis of chlamydial genital infection.     

Aerosol inoculation with a sub-lethal influenza virus leads to exacerbated morbidity and pulmonary disease pathogenesis

A mouse model has been extensively used to investigate disease intervention approaches and correlates of immunity following influenza virus infection. The majority of studies examining cross-reactive and protective immune responses have used intranasal (IN) virus inoculation; however, infectious aerosols are a common means of transmitting influenza in the human population. In this study, IN and aerosol routes of inoculation were compared and end-points of immunity and disease pathogenesis were evaluated in mice using mouse-adapted H3N2?A/Aichi/2/68 (x31). Aerosol inoculation with sub-lethal x31 levels caused more robust infection, which was characterized by enhanced morbidity, mortality, pulmonary cell infiltration, and inflammation, compared to IN-inoculated mice, as well as higher levels of IL-6 expression in the lung. Treatment with IL-6-blocking antibodies reduced pulmonary infiltrates and lung pathology in aerosol-inoculated mice. This study shows that aerosol inoculation results in a distinctive host response and disease outcome compared to IN inoculation, and suggests a possible role for IL-6 in lung pathogenesis.     

Streptococcus pyogenesinfection in mice

We inoculated 5 to 7-week-old female C3HeB/FeJ mice withStreptococcus pyogenesstrain B514-Sm (type M50) by both an intranasal and intratracheal route and characterized the resulting illness. Following intranasal inoculation, the animals developed signs of illness within 1 to 8 days post-inoculation which correlated with acute, suppurative, bronchopneumonia during histopathologic analysis; however, the relationship of response to dose was non-linear, as seen previously in a small group of mice.¹Intratracheal inoculations were then performed to increase the quantitative reliability of the model. Following intratracheal inoculation, the animals succumbed to an illness that was indistinguishable from that seen after intranasal inoculation, and the incidence of pneumonia followed a steep dose response curve. The dose at which 50% of the animals exhibited signs of respiratory illness within 72 h was 1.0×10⁷colony forming units. All of the animals that appeared ill had lung lesions as determined by gross and histopathologic examination. Bacteraemia followed pneumonia in two-thirds of the intratracheally inoculated animals, indicating that theS. pyogeneshad crossed tissue barriers. We hope that this model will be useful in future studies concerning the role of suspected streptococcal virulence factors in the later stages of pathogenesis of invasiveS. pyogenesinfection.     

Identification of the scavenger receptors SREC-I, Cla-1 (SR-BI), and SR-AI as cellular receptors for Tamm-Horsfall protein

Tamm-Horsfall protein (THP) is expressed exclusively in the kidney and constitutes the most abundant protein in urine. An important role for THP in antibacterial host defense but also in inflammatory disorders of the urogenital tract has been suggested. In line with this, THP has been shown recently to potently activate macrophages and dendritic cells (DC) via the toll-like receptor 4 (TLR4) pathway. We show here that THP interacts specifically with surface structures on DC and provides evidence that they are distinct from TLR4. Using retroviral expression cloning, we have identified one such receptor as the scavenger receptor (SR) expressed by endothelial cells I (SREC-I). In addition, we found that two other receptors for acetylated low-density lipoprotein (AcLDL), namely scavenger receptors AI (SR-AI) and Cla-1 (SR-BI), also serve as receptors for THP. SREC-I/THP interaction is of high affinity (16.8+/-6.8 nM), whereas Cla-1 and SR-AI have lower affinities for THP (396 nM+/-114 nM and 802 nM+/-157 nM, respectively). The interaction of THP with these molecules is fully blocked by AcLDL. However, AcLDL only partially blocks binding of THP to DC, and a series of experiments did not support a role in DC activation for SR interacting with THP and AcLDL. Thus, our data point to the existence of additional receptors for THP, which mediate TLR4-dependent DC activation. Interaction and up-take of THP by SR might play an important role in local host defense and could contribute to inflammatory kidney diseases associated with THP-specific antibody responses.     

Differential expression of immunoregulatory genes in monocytes in response to Porphyromonas gingivalis and Escherichia coli lipopolysaccharide

Porphyromonas gingivalis lipopolysaccharide (LPS) (strain W50) interacts with Toll‐like receptor 2 (TLR‐2) leading to cytokine expression and inflammation, and thereby plays a key role in the pathogenesis of periodontal disease. The aims of this study were to investigate gene expression of key regulatory mediators of innate immune responses in a human monocytic cell line (THP‐1) to P. gingivalis LPS and to compare these results with those obtained using the TLR‐4 ligand, Escherichia coli LPS. Custom‐made Taqman low‐density arrays were used for expression profiling of 45 different cytokine‐related genes. Both types of LPS highly up‐regulated interleukin (IL)‐1α and IL‐1β, IL‐18 receptor (IL‐18R), IL‐18R accessory protein and IL‐1 family (IL‐1F)9. Expression levels of IL‐1F6, IL‐1F7 and caspase‐1 were unaltered by either LPS. Genes for tumour necrosis factor‐α, IL‐6, leukaemia inhibitory factor and IL‐32 were also highly induced by both LPS. For a subset of genes, including CXC chemokine ligand 5 (CXCL5), expression was induced only by E. coli LPS or was up‐regulated more highly by E. coli compared with P. gingivalis LPS in THP‐1 monocytes. A similar expression pattern was also observed in dendritic cells. Analysis of signalling pathways which lead to CXCL5 expression indicated that the mechanisms underpinning the differential responses did not involve the recruitment of different adaptor proteins by TLR‐2 and TLR‐4, and therefore occur downstream of the receptor–adaptor complex. We conclude that differences in signalling pathways activated by TLR‐2 and TLR‐4 ligands lead to differential innate immune responses which may be important in polymicrobial diseases such as periodontal disease.     

Establishment of rat pneumococcal meningitis models: a histopathological analysis

The aim of this study was to perform a preliminary investigation of the pathogenesis of bacterial meningitis-induced brain injury by establishing rat pneumococcal meningitis models. Infant Wistar rats were intracranially inoculated with different concentrations of Streptococcus pneumoniae. Rats were sacrificed at different time points to observe clinical symptoms and pathological changes in brain tissues. Twenty-four hours after intracranial inoculation with Streptococcus pneumoniae, regardless of high or low concentrations of bacterial inoculation, all rats developed bacterial meningitis with manifestations such as lethargy and seizures. Pathological changes in brain tissues included subarachnoid and intraventricular inflammation, vasodilation and vascular congestion, and cortical neuronal necrosis. The number of rats with seizures, the degree of cerebral vascular disease, and the extent of neuronal damage were associated with the concentration of bacterial inoculum. Thirty days after infection, brain tissue weight significantly reduced. The pathological changes induced by inoculation with pneumococcal meningitis in Wistar rats were similar to those seen in the human brain. The possible mechanisms of brain damage caused by meningitis are cerebrovascular inflammation and disruption of regional cerebral blood flow.     

单核因子在Tamm-Horsfall蛋白所致肾小管间质肾炎纤维化形成中的作用

将Wistar大鼠的腹腔巨噬细胞(Mφ)分别与Tamm-Horsfall蛋白(THP,A组)、去糖基THP(B组)或RPMI1640(C组)在体外共育4小时,而后更换培养液继续孵育24小时。用生物学方法测定发现唯A组Mφ上清液含肿瘤坏死因子和IL-1样活性。将三组Mφ上清液分别注入各自大鼠右肾,6周后A组右肾全部发生了炎症和纤维化,伴有肾小管功能改变,而B、C组肾间质无明显异常。由此表明,THP对单核、Mφ的活化作用及由此而产生的生物活性介质可能在某些肾小管间质疾病纤维化的形成中具有重要意义。     

A TIN2 dyskeratosis congenita mutation causes telomerase-independent telomere shortening in mice

The progressive bone marrow failure syndrome dyskeratosis congenita (DC) is often caused by mutations in telomerase or the factors involved in telomerase biogenesis and trafficking. However, a subset of DC patients is heterozygous for mutations in the shelterin component TIN2. To determine how the TIN2-DC mutations affect telomere function, we generated mice with the equivalent of the TIN2 K280E DC allele (TIN2^DC) by gene targeting. Whereas homozygous TIN2^DC/DC mice were not viable, first-generation TIN2^+/DC mice were healthy and fertile. In the second and third generations, the TIN2^+/DC mice developed mild pancytopenia, consistent with hematopoietic dysfunction in DC, as well as diminished fecundity. Bone marrow telomeres of TIN2^+/DC mice shortened over the generations, and immortalized TIN2^+/DC mouse embryonic fibroblasts (MEFs) showed telomere shortening with proliferation. Unexpectedly, telomere shortening was accelerated in TIN2^+/DC mTR^−/− mice and MEFs compared with TIN2^+/+ mTR^−/− controls, establishing that the TIN2^DC telomere maintenance defect was not solely due to diminished telomerase action. The TIN2^DC allele induced mild ATR kinase signaling at telomeres and a fragile telomere phenotype, suggestive of telomere replication problems. These data suggest that this TIN2-DC mutation could induce telomeric dysfunction phenotypes in telomerase-negative somatic cells and tissues that further exacerbate the telomere maintenance problems in telomerase-positive stem cell compartments.     

Experimental autoimmune tubulointerstitial nephritis in guinea-pigs: effects on renal lesions of cyclophosphamide administered before and after tubular basement membrane immunization

To evaluate the role of immune cells, including suppressor cells, in the tubular basement membrane model (TBM) of autoimmune tubulointerstitial nephritis (TIN) in guinea-pigs, a single high dose of cyclophosphamide (200 mg/kg body weight) was administered intraperitoneally 72 hr before or 72 hr after TBM/FCA (Freund's complete adjuvant, 500 μg/ml) immunization. Animals were divided into control, Group I (TBM immunized, no cyclophosphamide), Group II (cyclophosphamide 72 hr before TBM immunization) and Group III (TBM immunization, 72 hr later cyclophosphamide). Renal lesions in Groups II and III were either mild or absent and no linear deposits of IgG on tubular basement membrane were observed; in contrast Group I animals had renal interstitial infiltrate of mononuclear and giant cells and linear IgG deposits on tubular basement membrane.

Since cyclophosphamide pretreatment at high dosages can remove susceptible suppressor cells and their precursors and enhance some forms of delayed hypersensitivity, the lack of enhanced renal lesions with 72 hr cyclophosphamide pretreatment suggests that subsets of antigen-specific suppressor cells sensitive to cyclophosphamide are not significant in the pathogenesis of the renal lesions of TIN; whereas, in animals given cyclophosphamide after immunization, absence of lesions reflects effect of cyclophosphamide on rapidly dividing cells. The findings also support the central role of anti-TBM autoantibody in the pathogenesis of this model of tubulointerstitial nephritis.