Isolation and differentiation of embryonic stem cells from BALB/c mouse

Objective To invest the efficient method which can culture and induce embryonic stem cells to neuroeyte in vitro. Methods Isolate the blastula o f 3.5 d from BALB/c species mouse. Culture the cells from inner cell mass （inner cell mass, ICM） which were isolated by mechanical method on the mouse embryonic fibroblaste cell （MEF） feeder layer or 0.1% gelatin coated dishes. The stem ceils were identified by characterized morphology, alkaline phosphatase stain, differential potency in vivo and immunoehemistry stain. The isolated cells were differentiated by serial induction method that mimicking the intrinsic developmental process of the neural system. Results The isolated cells were positive for alkaline phosphatatse and SSEA-1 （ stage specific embryonic antigen 1 ）. Moreover they were identified pluripotent by differentiation in vivo. Therefore the isolated ceils presented the characters of ESCs. Then the isolated cells were able to differentiate into neuroeytes in vitro. Conclusion Mouse embryonic stem ceils isolation, culture and differentiation system has been established.

Cow milkα_(s1)-casein induces allergic responses in a mouse model of atopy

α_(s1)-Casein is a potential allergen to induce hypersensitivity in cow milk.We had identifiedα_(s1)-casein and its epitopes in previous studies.The present study aimed to evaluate the allergic mechanism ofα_(s1)-casein in a BALB/c mouse model.The levels of specific IgE,mast cell proteinase,histamine and cytokines in sensitized mice were determined,and the clinical and pathological observation were evaluated.Results showed that the levels of specific IgE,mast cell proteinase,histamine,IL-4,IL-5,IL-10 increased significantly with a dose-dependent trend.The local alveolar septum collapsed or thickened,and lymphatic foci were produced in the spleen and thymus,and the inflammatory cells infiltrated in small intestinal mucosa mesenchyme.In conclusion,the levels of specific IgE,mast cell proteinase,histamine,IL-4,IL-5,IL-10 and some inflammatory factors could possibly serve as allergic biomarkers ofα_(s1)-casein,however,additional studies on signal transduction and gene expression are necessary in future.

Study on the Gene Transcription Level of Hippocampus NGF in C_(57) Mouse Development

β-Nerve growth factor (β NGF) mRNA levels in hippocampa from C57BL/6J mice of different ages were compared by semi-quantitative RT-PCR method, taking β-actin gene as an internal control. The levels of 6-and 12-month-old C57 mice were much lower compared with that of the l-month-old mouse. However, there was no significant difference between these two groups. This result suggests that gene transcription level of hippocampus β NGF in a C57, mouse descends evidently as it grows up. Base T at Site 294 of β NGF cDNA was substituted by C in the C57, mouse, as revealed by DNA sequencing for the first time. Nevertheless, this polymorphism of nucleotide did not make any difference in amino acid composition.

不同基因型牛病毒性腹泻病毒对BALB/c小鼠致病性研究

牛病毒性腹泻病毒(BVDV)是危害养牛业的重要病原。2021年本实验室从患有肺炎的牛肺中分离出1株BVDV(毒株编号为JS2201),经鉴定为1b亚型。为了评价该分离株的毒力与致病性,分别建立了分离株与参考株BVDV-1型Oregon C24V株、BVDV-2型C1602株BVDV感染BALB/c小鼠模型,通过检测攻毒后小鼠临床症状、体重变化、病毒血症情况、血液中白细胞与淋巴细胞的变化、组织器官的病理组织学变化及病毒载量,比较了分离株JS2201与1型和2型参考株的致病性差异。结果显示:BVDV分离株JS2201与参考株均能够成功感染BALB/c小鼠,攻毒BALB/c小鼠均形成病毒血症,导致血液中白细胞数量、淋巴细胞数量以及淋巴细胞百分比短暂下降;BVDV分离株JS2201株攻毒组小鼠肝脏、肾脏、肺脏、脾脏中BVDV载量要高于C24V、C1602株攻毒组;攻毒组小鼠均表现为间质性肺炎病变,JS2201株攻毒组与1型参考株C24V株攻毒组小鼠肺脏病理组织学变化相似,BVDV-2型参考株C1602株攻毒组小鼠肺脏病变更为严重。综上,本研究成功建立了不同亚型BVDV急性感染BALB/c小鼠的模型,且比较分析了分离株与参考株之间的致病性差异,为BVDV疫苗的研制以及致病机制的研究奠定了基础。

面愈贴促进Balb/c小鼠急性面神经损伤后神经功能恢复的作用机制

目的 研究面愈贴促进急性面神经损伤神经功能恢复的作用和可能的机制。方法 随机将120只无特定病原体(SPF)雄性Balb/c小鼠分为假手术组(Sham组,n=40)、模型组(Model组,n=40)和治疗组(M+MYT组,n=40)。模型组和M+MYT组小鼠压榨面神经主干建立急性面神经损伤模型。造模成功后,M+MYT组小鼠给予面愈贴贴敷治疗24 h, Sham组和Model组不做处理。各组每24 h进行面神经功能评分。术后第9天采集脑干面神经核、面神经主干组织和眼球静脉血样本;苏木精-伊红(HE)染色和透射电子显微镜观察面神经主干和面神经核神经元的形态变化;免疫荧光和蛋白质免疫印迹分别检测小鼠面神经核单核细胞趋化蛋白-1(MCP-1)、肿瘤坏死因子-α(TNF-α)、诱导型一氧化氮合酶(iNOS)、内皮型一氧化氮合酶(eNOS)、内皮素-1(ET-1)和血管内皮生长因子(VEGF)表达;酶联免疫吸附试验(ELISA)检测小鼠血清MCP-1、TNF-α、iNOS、eNOS、ET-1和VEGF表达;硝酸还原法检测血清中一氧化氮(NO)浓度。结果 术后第9天,M+MYT组小鼠面神经功能评分低于Model组(P<0.05);HE染色和透射电子显微镜显示,M+MYT组面神经核神经元和神经纤维的损伤较Model组明显改善;免疫荧光、蛋白质免疫印迹和ELISA检测显示,M+MYT组MCP-1、TNF-α、iNOS、ET-1和VEGF表达显著低于Model组(P<0.05),而eNOS表达高于Model组(P<0.05);硝酸还原法显示,NO浓度以M+MYT组最高,Sham组最低(P<0.01)。结论 面愈贴可降低急性面神经损伤后MCP-1、TNF-α、iNOS、ET-1及VEGF表达,增强eNOS和NO表达,有效控制炎症,保护微血管内皮功能,降低血管通透性,促进神经功能恢复。

基于Micro-CT的BALB/c小鼠肺腺瘤动物模型研究

目的 建立基于Micro-CT动态表征的BALB/c小鼠肺腺瘤动物模型研究方法。方法 取80只SPF级雌性BALB/c小鼠,随机分为4组:模型低剂量组(1 mg/g乌拉坦腹腔注射1次)、模型中剂量组(1 mg/g乌拉坦腹腔注射,每周1次,连续2周)、模型高剂量组(1 mg/g乌拉坦腹腔注射,每周1次,连续4周)和空白组(等体积生理盐水腹腔注射)。采用Micro-CT定期监测小鼠肺结节生长情况,Analyze 12.0分析系统绘制小鼠肺部3D图像,苏木素-伊红(HE)染色观察肺组织病理学变化。结果 与空白组相比,各模型组小鼠第11周时均观测到类圆形高密度影的肺结节。结节形成率随造模周数增加而升高,至第21周时,模型高、中、低剂量组结节形成率分别为93.8%、93.8%、87.5%;结节数分别以2~4个、1个、1~2个为主;低剂量组肺结节最大直径平均值高于中、高剂量组(P<0.05);肺结节体积三组之间差异无统计学意义。HE染色结果显示模型高、中、低剂量组病理类型均为肺腺瘤。结论 模型各剂量组均成功诱导肺腺瘤,Micro-CT可对小鼠肺结节生长情况进行表征,其中模型中剂量组结节形成率高,肺腺瘤数量适中,模型稳定,更适合小鼠肺腺瘤动物模型的研究。

美洛昔康对荷瘤BALB/c小鼠的围手术期镇痛效果

目的为了降低肿瘤切除术过程中小鼠的围手术期疼痛,保障动物福利最大化和研究数据的准确性,本研究探究美洛昔康对荷瘤小鼠的围手术期镇痛作用。方法所有BALB/c小鼠均采用舒泰和右美托嘧啶的麻醉方案,分为对照组(A组)和美洛昔康注射组(B组)。采用面部表情评分系统和疼痛行为频率评估小鼠的疼痛程度;监测小鼠的体质量以及脏器的组织病理学方法评估其围手术期安全性。结果B组小鼠的麻醉诱导时间较A组缩短,苏醒时间较A组显著延长(P<0.01);术后3 d内,B组小鼠的面部表情评分和疼痛行为频率较A组显著降低;两组小鼠的主要脏器和肠道组织在组织病理学上均无明显病变,体质量无显著差异,B组小鼠全部存活。结论舒泰和右美托嘧啶麻醉方案联合美洛昔康可以缩短BALB/c小鼠的麻醉诱导时间并使其缓慢苏醒,显著地降低了小鼠的围手术期疼痛,且是安全的。

SOCS3 Expression Correlates with Severity of Inflammation in Mouse Hepatitis Virus Strain 3-induced Acute Liver Failure and HBV-ACLF

Summary： Recently, suppressor of cytokine signaling-3 （SOCS3） has been shown to be an inducible endogenous negative regulator of Janus kinase/signal transducers and activators of transcription （JAK/STAT） pathway which is relevant in inflammatory response, while its functions in acute liver failure and HBV-induced acute-on-chronic liver failure （HBV-ACLF） have not been fully elucidated. In this study, we explored the role of SOCS3 in the development of mouse hepatitis virus strain 3 （MHV-3）-induced acute liver failure and its expression in liver and peripheral blood mononuclear cells （PBMCs） of patients with HBV-ACLF. Inflammation-related gene expression was detected by real-time PCR, immtmohistochemistry and Western blotting. The correlation between SOCS3 level and liver injury was studied. Our results showed that the SOCS3 expression was significantly elevated in both the liver tissue and PBMCs from patients with HBV-ACLF compared to mild chronic hepatitis B （CHB）. Moreover, a time course study showed that SOCS3 level was increased remarkably in the liver of BALB/cJ mice at 72 h post-infection. Pro-inflammatory cytokines, interleukin （IL）-1 β, IL-6, and tumor necrosis factor （TNF）-α, were also increased significantly at 72 h post-infection. There was a close correlation between hepatic SOCS3 level and IL-6, and the severity of liver injury defined by alanine aminotransferase （ALT） and aspartate aminotransferase （AST） levels, respectively. These data suggested that SOCS3 may play a pivotal role in the pathogenesis of MHV-3-induced acute liver failure and HBV-ACLF.

腹腔注射攻毒建立蜱媒脑炎病毒感染BALB/c小鼠模型

目的通过腹腔注射攻毒途径建立蜱媒脑炎病毒(TBEV)感染BALB/c小鼠模型,观察小鼠的感染症状和病毒在小鼠体内的复制特征。方法将6周龄雌性BALB/c小鼠随机分为未感染病毒对照组、1×10^(3)空斑形成单位(PFU)TBEV感染组(以每只小鼠1×10^(3)PFU的攻毒剂量经腹腔注射感染小鼠)、1×10^(4)PFU TBEV感染组(以每只小鼠1×10^(4)PFU的攻毒剂量经腹腔注射感染小鼠),观察小鼠的感染症状、体重变化与生存情况。通过H-E染色观察小鼠脑、脾的病理改变,采用免疫组织化学染色检测小鼠脑、脾中TBEV蛋白的表达,采用空斑试验检测小鼠脑、脾中TBEV滴度的动态变化。结果1×10^(4)PFU TBEV感染组小鼠于感染后第6天出现弓背、后肢瘫痪等感染症状,1×10^(3)PFU TBEV感染组小鼠于感染后第7天出现上述症状。与未感染病毒对照组小鼠相比,1×10^(4)PFU TBEV感染组小鼠从第5天、1×10^(3)PFU TBEV感染组小鼠从第6天开始体重明显降低,差异有统计学意义(P<0.05)。1×10^(4)PFU TBEV感染组小鼠第7天开始死亡、第8天全部死亡,1×10^(3)PFU TBEV感染组小鼠第7天开始死亡、第9天全部死亡。H-E染色结果显示,TBEV感染后第5天、第7天小鼠大脑皮质仅出现少量神经元核固缩、深染,未观察到炎症细胞浸润;TBEV感染后第5天小鼠脾红髓轻度淤血、多见中性粒细胞,第7天中性粒细胞数量增多。免疫组织化学染色结果显示,TBEV感染后第5天小鼠脑与脾少量表达TBEV蛋白,第7天TBEV蛋白表达量增加。1×10^(3)PFU TBEV感染第7天,小鼠脑内TBEV滴度高达(1.3±0.6)×10^(5)PFU/mL,而脾中TBEV滴度为(1.3±0.6)×10^(3)PFU/mL。结论经腹腔注射攻毒成功建立了TBEV感染BALB/c小鼠模型,TBEV可在小鼠体内增殖并具致病性。

Establishment of an orthotopic pancreatic cancer mouse model: Cells suspended and injected in Matrigel

AIM: To establish an orthotopic mouse model of pancreatic cancer that mimics the pathological features of exocrine pancreatic adenocarcinoma.

TLR4-HMGB1-, MyD88- and TRIF-dependent signaling in mouse intestinal ischemia/reperfusion injury

AIM: To characterize high-mobility group protein 1-toll-like receptor 4(HMGB1-TLR4) and downstream signaling pathways in intestinal ischemia/reperfusion(I/R) injury.METHODS: Forty specific-pathogen-free male C57BL/6 mice were randomly divided into five groups(n = 8 per group): sham, control, anti-HMGB1, anti-myeloid differentiation gene 88(My D88), and anti-translocatingchain-associating membrane protein(TRIF) antibody groups. Vehicle with the control Ig G antibody, antiHMGB1, anti-My D88, or anti-TRIF antibodies(all 1 mg/kg, 0.025%) were injected via the caudal vein 30 min prior to ischemia. After anesthetization, the abdominal wall was opened and the superior mesenteric artery was exposed, followed by 60 min mesenteric ischemia and then 60 min reperfusion. For the sham group, the abdominal wall was opened for 120 min without I/R. Levels of serum nuclear factor(NF)-κB p65, interleukin(IL)-6, and tumor necrosis factor(TNF)-α were measured, along with myeloperoxidase activity in the lung and liver. Inaddition,morphologic changes that occurred in the lung and intestinal tissues were evaluated. Levels of m RNA transcripts encoding HMGB1 and NF-κB were measured by real-time quantitative PCR, and levels of HMGB1 and NF-κB protein were measured by Western blot. Results were analyzed using one-way analysis of variance.RESULTS: Blocking HMGB 1, MyD 8 8, and TRIF expression by injecting anti-HMGB1, anti-My D88, or anti-TRIF antibodies prior to ischemia reduced the levels of inflammatory cytokines in serum; NF-κB p65: 104.64 ± 11.89, 228.53 ± 24.85, 145.00 ± 33.63, 191.12 ± 13.22, and 183.73 ± 10.81(P < 0.05); IL-6: 50.02 ± 6.33, 104.91 ± 31.18, 62.28 ± 6.73, 85.90 ± 17.37, and 78.14 ± 7.38(P < 0.05); TNF-α, 43.79 ± 4.18, 70.81 ± 6.97, 52.76 ± 5.71, 63.19 ± 5.47, and 59.70 ± 4.63(P < 0.05) for the sham, control, anti-HMGB1, anti-My D88, and anti-TRIF groups, respectively(all in pg/m L).Antibodies also alleviated tissue injury in the lung and small intestine compared with the control group in the mouse intestinal I/R model. The administration of antiHMGB1, anti-My D88, and anti-TRIF antibodies markedly reduced damage caused by I/R, for which anti-HMGB1 antibody had the most obvious effect.CONCLUSION: HMGB1 and its downstream signaling pathway play important roles in the mouse intestinal I/R injury, and the effect of the TRIF-dependent pathway is slightly greater.

BALB/cSpf小鼠和野生型BALB/c小鼠生物学特性比较

目的比较分析BALB/cSpf小鼠与野生型BALB/c(N-BALB/c,N:normal)小鼠生物学特性指标差异,为其实验应用提供基础数据。方法3~12周,每周对雌雄BALB/cSpf小鼠和N-BALB/c小鼠生长曲线、采食量、饮水量进行统计分析;取BALB/cSpf小鼠雌性和N-BALB/c小鼠雌性各30只,二雌一雄长期同居交配方式繁殖饲养,记录产仔数,产仔性别;采集血液进行17项血液生化指标和22项血液生理指标测定。结果BALB/cSpf小鼠和N-BALB/c小鼠采食量和饮水量差异不显著(P>0.05),BALB/cSpf小鼠体质量显著高于N-BALB/c小鼠(雌性从第5周开始,雄性从第3周开始)。1~3胎产仔数及产仔性别差异不显著。雌性BALB/cSpf小鼠生理指标WBC、Neu、Lym、RBC、HGB、HCT、MPV、PDW显著高于N-BALB/c小鼠(P<0.01)。雄性BALB/cSpf小鼠生理指标WBC、Neu、Lym、Mon、HCT、MCHC显著低于N-BALB/c小鼠(P<0.01)。雌性BALB/cSpf小鼠生化指标UREA显著高于N-BALB/c小鼠(P<0.05);AST、CK、LDH显著低于N-BALB/c小鼠(P<0.01)。BALB/cSpf小鼠生化指标TG、TC、LIP、UREA、MgⅡ显著高于N-BALB/c小鼠(P<0.01);ALT、AST、Glu-G、Ca显著低于N-BALB/c小鼠(P<0.01)。结论BALB/cSpf小鼠和N-BALB/c小鼠生物学特性有一定差异。

Insights into sensitizing and eliciting capacity of gastric and gastrointestinal digestion products of shrimp(Penaeus vannamei)proteins in BALB/c mice

Shrimp(Penaeus vannamei)proteins have been shown an allergenic potential;however,little information is available on the sensitizing and eliciting capacity of shrimp protein digestion products.In this study,a BALB/c mice model was used to explore the allergenicity of shrimp protein sample(SPS)and their gastric and gastrointestinal digestion products(GDS/GIDS).As compared with the SPS groups,the GDS/GIDS groups caused lower specific immunoglobulins(Ig E/Ig G1)levels(P<0.05),but higher than the control groups,indicating that the digestion products sensitized the mice.Meanwhile,spleen index,mouse mast cell protease-1(m MCP-1)concentration and proportion of degranulated mast cells were significantly reduced in the GDS/GIDS groups(P<0.05);simultaneously,allergic symptoms,vascular permeability and histopathological changes of tissues were alleviated.Nevertheless,the allergenicity of digestion products cannot be eliminated and still cause systemic allergic reactions in mice.The study showed that the digestion products of shrimp still had high sensitizing and eliciting capacity.

Transglutaminase 3 expression in C57BL/6J mouse embryo epidermis and the correlation with its differentiation

Epidermal-type transglutaminase 3 (TGM3) is involved in the cross-linking of structural proteins to form the cornifiedenvelope in the epidermis. In the present study, we detected the expression of TGM3 in the mouse embryo using RT-PCR.TGM3 mRNA is weakly presented from E11.5 to E14.5 and increases significantly from E15.5 to birth. Then wedetermined the spatial and temporal expression pattern of TGM3 in the skin and other organs by in situ hybridization. Wefound a deprivation of TGM3 in skin at E11.5, while a rich supply in periderm cells and a weak expression in basal cellsfrom E12.5 to E14.5. From the period of E15.5 to E16.5, after keratinization in the epidermis, TGM3 was expressed inthe granular and cornified layers. The electron microscopic observation of the C57BL/6J mouse limb bud skin develop-ment provided several morphological evidences for the epidermal differentiation. The above findings suggest that theexpression of TGM3 plays a important role in the epidermis differentiation in embryogenesis.

Hepatocellular carcinoma xenograft supports HCV replication:A mouse model for evaluating antivirals

AIM: To develop a hepatocellular carcinoma (HCC) xenograft model for studying hepatitis C virus (HCV) replication in a mice, and antiviral treatment.METHODS: We developed a stable S3-green fluorescence protein (GFP) cell line that replicated the GFP-tagged HCV sub-genomic RNA derived from a highly efficient JFH1 virus. S3-GFP replicon cell line was injected subcutaneously into γ-irradiated SCID mice. We showed that the S3-GFP replicon cell line formed human HCC xenografts in SCID mice. Cells were isolated from subcutaneous tumors and then serially passaged multiple times in SCID mice by culturing in growth medium supplemented with G-418. The mouse-adapted S3-GFP replicon cells were implanted subcutaneously and also into the liver of SCID mice via intrasplenic infusion to study the replication of HCV in the HCC xenografts. The tumor model was validated for antiviral testing after intraperitoneal injection of interferon-α (IFN-α). RESULTS: A highly tumorigenic S3-GFP replicon cell line was developed that formed subcutaneous tumors within 2 wk and diffuse liver metastasis within 4 wk in SCID mice. Replication of HCV in the subcutaneous and liver tumors was confirmed by cell colony assay, detection of the viral RNA by ribonuclease protection assay and real-time quantitative reverse transcription polymerase chain reaction. High-level replication of HCV sub-genomic RNA in the tumor could be visualized by GFP expression using fluorescence microscopy. IFN-α cleared HCV RNA replication in the subcutaneous tumors within 2 wk and 4 wk in the liver tumor model. CONCLUSION: A non-infectious mouse model allows us to study replication of HCV in subcutaneous and metastatic liver tumors. Clearance of HCV by IFN-α supports use of this model to test other anti-HCV drugs.

Influence of whole peptidoglycan of bifidobacterium on cytotoxic effectors produced by mouse peritoneal macrophages

INTRODUCTIONBifidobacteria are physiologically beneficial bacteria which are perdominant in human intestine ,and possess the most important functions .They play an important role in maintaining microbial balance of the intestine .Furthermore , their presence is thought to be an important indication of health of the body [1-4].Whole peptidoglycan ( WPG) is the major component in the cell wall of bifidobacterium ,which is also a biological responsemodifier with nontoxic side dffcets.

Axonal damage in myelin oligodendrocyte glycoprotein peptide-induced experimental autoimmune encephalomyelitis in a C57BL/6 mouse model may be not secondary to inflammatory demyelination

The present study established a chronic experimental autoimmune encephalomyelitis model in C57BL/6 mice induced by myelin oligodendrocyte glycoprotein peptides and complete Freund＇s adjuvant. Onset latency was 12 days, with an incidence rate of 100%. Neuropathological characteristics included perivascular inflammatory cell infiltration, demyelination, neuronal degeneration, and axonal damage within cerebral and myelic white matter. Electron microscopy revealed swollen mitochondria, complete organ disappearance, and fused or broken myelin sheath structure, which were accompanied by myelin sheath reconstruction. Moreover, axonal damage was not consistent with demyelination distribution, and severity of axonal damage did not correlate with demyelination. Results suggested that axonal damage in an experimental autoimmune encephalomyelitis model is not secondary to inflammatory demyelination.

Neurodevelopmental Timing of Ethanol Exposure May Contribute to Observed Heterogeneity of Behavioral Deficits in a Mouse Model of Fetal Alcohol Spectrum Disorder (FASD)

Maternal drinking during pregnancy can result in a wide spectrum of cognitive and behavioral abnormalities termed fetal alcohol spectrum disorders (FASD). The heterogeneity observed in FASD-related phenotypes can be attributed to a number of environmental and genetic factors;however, ethanol dose and timing of exposure may have significant influences. Here, we report the behavioral effects of acute, binge-like ethanol exposure at three neurodevelopmental times corresponding to the first, second, and third trimester of human development in C57BL/6J mice. Results show that developmental ethanol exposure consistently delays the development of basic motor skill reflexes and coordination as well as impairs spatial learning and memory. Observed changes in activity and anxiety-related behaviors, however, appear to be dependent on timing of alcohol exposure. The variability in behaviors between different treatment models suggests that these may be useful in evaluating the mechanisms disrupted by ethanol at specific neurodevelopmental times. The results provide further evidence that, regardless of developmental stage, the developing brain is acutely sensitive to alcohol exposure.

Contributions of transgenic mouse studies on the research of hepatitis B virus and hepatitis C virus-induced hepatocarcinogenesis

Transgenic mouse technology has enabled the investigation of the pathogenic effects, including those on development, immunological reactions and carcinogenesis, of viral genes directly in living organism in a real-time manner. Although viral hepatocarcinogenesis comprises multiple sequences of pathological events, that is, chronic necroinflammation and the subsequent regeneration of hepatocytes that induces the accumulation of genetic alterations and hepatocellular carcinoma(HCC), the direct action of viral proteins also play significant roles. The pathogenesis of hepatitis B virus X and hepatitis C virus(HCV) core genes has been extensively studied by virtue of their functions as a transactivator and a steatosis inducer, respectively. In particular, the mechanism of steatosis in HCV infection and its possible association with HCC has been well studied using HCV core gene transgenic mouse models. Although transgenic mouse models have remarkable advantages, they are intrinsically accompanied by some drawbacks when used to study human diseases. Therefore, the results obtained from transgenic mouse studies should be carefully interpreted in the context of whether or not they are well associated with human pathogenesis.

Changes of the intestinal endocrine cells in the C57BL/6 mouse after implantation of murine lung carcinoma (3LL): An immunohistochemical quantitative study

AIM: To study the distributions and frequencies of intestinal endocrine cells in the C57BL/6 mouse with immunohistochemical method using seven types of specific antisera against chromogranin A (CGA), serotonin,somatostatin, glucagons, gastrin, cholecystokinin (CCK)-8 and human pancreatic polypeptide (hPP) after abdominal subcutaneous implantation of murine lung carcinoma (3LL).METHODS: The experimental animals were divided into two groups, one is non-implanted Sham and the other is 3LL-implanted group. Samples were collected from six regions of intestinal tract at 28th d after implantation of 3LL cells (1×105 cell/mouse).RESULTS: In this study, five types of immunoreactive (IR) cells were identified except for gastrin and hPP. The regional distributions of the intestinal endocrine cells in the 3LL-implanted group were similar to those of the non-implanted Sham. However, significant decreases of IR cells were detected in 3LL-implanted group compared to those of non-implanted Sham. CGA- and serotonin-IR cells significantly decreased in 3LL-implanted groups compared to that of non-implanted Sham. Somatostatin-IR cells in the jejunum and ileum and CCK-8-IR cells in the jejunum of 3LL-implanted groups significantly decreased compared to that of non-implanted Sham. In addition,glucagon-IR cells were restricted to the ileum and colon of non-implanted Sham.CONCLUSION: Implantation of tumor cell mass (3LL)induced severe quantifiable changes of intestinal endocrine cell density and the abnormality in density of intestinal endocrine cells may contribute to the development of gastrointestinal symptoms such as anorexia and indigestion, frequently encountered in patients with cancer.