基于细胞高内涵分析表征氮芥HN-3的细胞毒性

目的研究氮芥HN-3对不同来源细胞的毒性表型特征。方法 HN-3100,300和450μmol·L^(-1)分别作用于原代人胚表皮角质细胞(HEKf),原代成人皮肤成纤维细胞(HDFa)和人肺成纤维细胞(HLF)0.5,2,4,6,8,24和48 h后,采用基于细胞成像的多参数分析技术,检测HN-3对细胞存活、细胞核、细胞骨架(微丝和微管)、线粒体膜电位(MMP)、氧化应激、核膜通透性(NMP)、磷酸化组蛋白、溶酶体、自噬、细胞周期和凋亡等参数的影响。结果 HN-3引起不可逆性的细胞损伤,表现为存活细胞数量显著减少(P<0.01)。在存活细胞数量显著减少前,从0.5 h开始,细胞内活性氧和磷酸化组蛋白水平即显著升高,谷胱甘肽含量显著降低(P<0.01)。HEKf细胞内溶酶体在0.5 h时减少,而HDFa和HLF细胞内溶酶体则分别在0.5和2 h升高,并伴有微管相关蛋白1轻链3B(LC3B)蛋白表达升高伴随存活细胞数量减少,HEKf细胞核亮度升高,核面积减少,微丝、微管亮度和面积减少,MMP显著降低(P<0.01),溶酶体亮度有增加趋势;与此相反,HDFa和HLF细胞表现为核面积增加,微丝、微管亮度和面积增加,MMP显著升高(P<0.01),但溶酶体亮度增加,且HLF细胞LC3B的含量显著升高(P<0.01);同时,3种细胞均有NMP增高和锰超氧化物歧化酶含量增加,G2期阻滞。此外,HEKf细胞出现早期和晚期凋亡,HDFa细胞出现早期凋亡。结论 HN-3诱发早期的细胞损伤效应包括DNA损伤、氧化胁迫和溶酶体损伤,晚期导致MMP失衡、NMP增加、G2期细胞周期阻滞;此外,HN-3特异性地诱导HEKf细胞核固缩、细胞骨架蛋白核聚集和细胞凋亡;诱导HDFa和HLF细胞核肿胀和细胞骨架松散,并最终导致HDFa细胞早凋和HLF细胞自噬性死亡。

Effect of Herpes Simplex Virus-2 Infection in Vitro on the Expression of HLA Class II Antigen of Monocytes

Objectives: In order to investigate the role of mono-cytes and human leukocyte antigen (HLA) class II an-tigen in herpes simplex virus-2 (HSV-2) infection, westudied the effect of HSV-2 infection in vitro on theexpression of HLA class II antigen on monocytes.Methods: Monocytes were infected with HSV-2(Strain 333). Culture cells were collected 1, 3, 5 and 7days after infection. The levels of expression of HLAclass II antigen were measured by using alkaline phos-phatase antialkaline phosphatase method (APAAP).Results: The levels of the expression of HLA class IIantigen on monocytes significantly decreased on thefirst day of post-infection, and then gradually returnedto levels found in the controls by the 7th day post-infection.Conclusion: HLA class II antigen expression onmonocytes was inhibited with HSV-2 infection, whichmight be one means of virus escape at an early phase.The expression of HLA class II antigen may play animportant role in herpes simplex viurs-2 pathogenic-ity and immunity.

Memory CD8+ T cell differentiation in viral infection: A cell for all seasons

Chronic viral infections such as hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) are major global health problems affecting more than 500 million people worldwide. Virus-specific CD8+ T cells play an important role in the course and outcome of these viral infections and it is hypothesized that altered or impaired differentiation of virus- specific CD8+ T cells contributes to the development of persistence and/or disease progression. A deeper understanding of the mechanisms responsible for functional differentiation of CD8+ T cells is essential for the generation of successful therapies aiming to strengthen the adaptive component of the immune system.

Development of HBsAg-Binding Aptamers that bind HepG2.2.15 cells via HBV surface antigen

Hepatitis B virus surface antigen （HBsAg）, a specific antigen on the membrane of Hepatitis B virus （HBV）-infected cells, provides a perfect target for therapeutic drugs. The development of reagents with high affinity and specificity to the HBsAg is of great significance to the early-stage diagnosis and treatment of HBV infection. Herein, we report the selection of RNA aptamers that can specifically bind to HBsAg protein and HBsAg-positive hepatocytes. One high affinity aptamer, HBs-A22, was isolated from an initial 115 met library of -1.1 ×10^15 random-sequence RNA molecules using the SELEX procedure. The selected aptamer HBs-A22 bound specifically to hepatoma cell line HepG2.2.15 that expresses HBsAg but did not bind to HBsAg-devoid HepG2 cells. This is the first reported RNA aptamer which could bind to a HBV specific antigen. This newly isolated aptamer could be modified to deliver imaging, diagnostic, and therapeutic agents targeted at HBV-infected cells.

The influence of hepatitis B virus X protein on the clock genes in liver cells and its significance

Objective： The aim of this study was to investigate the influence of hepatitis B virus X protein （HBx） on the clock genes in LO2 cells and its significance. Methods： A cell line LO2-HBx, Stably transfected with HBx gene, was established. The levels of mRNA and protein expression of CLOCK and BMAL1 were detected by real-time PCR and western blot. Resuits： The expression of CLOCK mRNA and protein were increased in cell line LO2-HBx （P 〈 0.05）, while the expression of BMAL1 mRNA and protein were decreased in cell line LO2-HBx （P 〈 0.05）. Conclusion： The expressions of core clock gene CLOCK and BMAL1 have been changed by HBx, which breaks down the previous circadian rhythm of liver cells. This maybe one of the reasons leads to the formation of liver cancer.

Significance of hepatitis B virus surface antigen, hepatitis C virus expression in hepatocellular carcinoma and pericarcinomatous tissues

AIM： To investigate the correlation between hepatitis B virus surface antigen （HBsAg）, hepatitis C virus （HCV） expression in hepatocellular carcinoma （HCC）, the HAI score of the noncancerous region of the liver and the serum Alpha fetoprotein （AFP） level. METHODS： The patterns of HBsAg and HCV in 100 cases of HCC and their surrounding liver tissues were studied on paraffin-embedded sections with immunohistochemistry, the histological status was determined by one pathologist and one surgeon simultaneously using the hepatitis activity index （HAIl score, and AFP was detected by radioimmunity. The study included 100 consecutive patients who underwent curative resection for HCC. Based on HBsAg and HCV expression, the patients were classified into 4 groups： patients positive for HBsAg （HBsAg group）, patients positive for HCV （HCV group）, patients negative for both HCV and HBsAg （NBNC group） and patients positive for both HBsAg and HCV （BC group）. RESULTS： The BC group had significantly higher HAI scores than the other three groups. （BC 〉 HCV 〉 HBsAg 〉 NBNC）. HBV and HCV virus infection was positively correlated with HAI （rs = 0.39, P = 0.00011. The positive rate of AFP （85.7%） and the value of AFP （541.2 ng/mL） in the group with HBV and HCV co-infection were the highest among the four groups. The positive rate （53.3%） of AFP and the value of AFP （ 53.3 ng/mL） in the group with none-infection of HBV and HCV were the lowest. HBV and HCV virus infection was positively correlated with AFP（rs = 0.38, P = 0.0001）. CONCLUSION： The AFP increase in patients with liver cancer was positively correlated with the infection of HBV and HCV. The-serum AFP elevation by the infection of HBV and HCV is one of mechanisms which lead to hepatocarcinogenesis, and the antivirus intervening treatment of hepatitis is significant for the prognosis of liver cancer. From our Spearman＇s rank correlation analysis, we can conclude that the severity of virally induced inflammation is correlated with HBsAg and HCV expression in HCC tissues and noncancerous tissues. Prior co-infection of HBV in HCV patients may be an adverse risk factor for intrahepatic inflammation.

The phenotype and activation status of regulatory T cells during Friend retrovirus infection

The suppressive capacity of regulatory T cells （Tregs） has been extensively studied and is well established for many diseases.The expansion,accumulation,and activation of Tregs in viral infections are of major interest in order to find ways to alter Treg functions for therapeutic benefit.Tregs are able to dampen effector T cell responses to viral infections and thereby contribute to the establishment of a chronic infection.In the Friend retrovirus （FV） mouse model,Tregs are known to expand in all infected organs.To better understand the characteristics of these Treg populations,their phenotype was analyzed in detail.During acute FV-infection,Tregs became activated in the spleen and bone marrow,as indicated by various T cell activation markers,such as CD43 and CD103.Interestingly,Tregs in the bone marrow,which contains the highest viral loads during acute infection,displayed greater levels of activation than Tregs from the spleen.Treg expansion was driven by proliferation but no FV-specific Tregs could be detected.Activated Tregs in FV-infection did not produce Granzyme B （GzmB） or tumor necrosis factor α （TNFα）,which are thought to be a potential mechanism for their suppressive activity.Furthermore,Tregs expressed inhibitory markers,such as TIM3,PD-1 and PD-L1.Blocking TIM3 and PD-L1 with antibodies during chronic FV-infection increased the numbers of activated Tregs.These data may have important implications for the understanding of Treg functions during chronic viral infections.

Transient Expression of Human Papillomavirus Type 16(HPV 16) mRNA in Normal Human Keratinocytes Transfected by pSV2-neo/16

Objective: To investigate the expression of HPV16 mRNA innormal human keratinocytes transfected with pSV2-neo/16. Methods: First human keratinocytes were cultured in theserum-free medium M154.Second, the plasmid pSV2-neo/16was transfected into the human keratinocytes using atransfecting reagent. Third, RT-PCR and Southern Blottingwere used to detect the expression of HPV16 mRNA and DNAin the transfected keratinocytes, respectively. Results: The expression of HPV 16 mRNA was successfullyamplified and an 110bp was detected by RT-PCR. A 7.9kbfragment was confirmed in the transfected keratinocytes bySouthern Blot analysis. Conclusion: HPV 16 mRNA and DNA were successfullydetected in the human keratinocytes.