Profound CD4+ T lymphocytopenia in human immunodeficiency virus negative individuals,improved with anti-human herpes virus treatment

Lymphocytopenia and CD4+ T lymphocytopenia can be associated with many bacterial, fungal, parasite and viral infections. They can also be found in autoimmune and neoplastic diseases, common variable immunodeficiency syndrome, physical, psychological and traumatic stress, malnutrition and immunosuppressive therapy. Besides, they can also be brought into relation, without a known cause, with idiopathic CD4+ T lymphocytopenia. Among viral infections, the Retrovirus, specially the human immunodeficiency virus, is the most frequently cause. However, many acute viral infections, including cytomegalovirus and Epstein Barr virus can be associated with transient lymphocytopenia and CD4+ T lymphocytopenia. As is well known, transient lymphocytopenia and CD4+ T lymphocytopenia are temporary and overcome when the disease improves. Nonetheless, severe CD4+ T Lymphocytopenia associated with chronic infections by human herpes virus has not been reported. We describe 6 cases of human immunodeficiency virus negative patients, with chronic cytomegalovirus and Epstein Barr virus infections and profound lymphocytopenia with clinical symptoms of cellular immunodeficiency. These patients improved rapidly with ganciclovir or valganciclovir treatment. We claim here that it is important to consider the chronic human herpes virus infection in the differential diagnosis of profoundly CD4+ T lymphocytopenia etiology, when human immunodeficiency virus is absent, in order to start effective treatment and to determine, in future studies, the impact of chronic human herpes virus infection in human beings'' health.     

基因多态性对人胎盘ABCG2基因mRNA及其蛋白表达的影响

目的 评估单核苷酸多态位点对人胎盘ABCG2基因mRNA及蛋白表达的影响.方法 选择2013年3月至5月在四川大学华西第二医院产科待产分娩的46例汉族正常孕产妇及新生儿为研究对象,收集其胎盘及脐带标本（本研究遵循的程序符合四川大学华西第二医院人体试验委员会制定的伦理学标准,得到该委员会批准,获得胎盘及脐带标本时均取得产妇及家属的知情同意,并与之签署临床研究知情同意书）.其中,脐带标本用于胎儿DNA的提取,胎盘标本用于ABCG2基因的RNA及蛋白提取;通过测序确定ABCG2基因421C＞A及34G＞A多态位点的基因型;分别通过实时荧光定量（RT）-PCR及Western-blotting法获得ABCG2基因的mRNA及蛋白表达情况.对ABCG2基因421C＞A及34G＞A多态位点不同基因型之间mRNA及蛋白相对表达量进行比较.ABCG2基因421C＞A及34G＞A多态位点不同基因型之间孕产妇及新生儿一般临床资料比较,差异均无统计学意义（P＞0.05）.结果 对于421C＞A多态位点,携带CC、CA、AA各基因型的胎盘标本的平均mRNA及蛋白表达水平比较,其差异均无统计学意义（F=1.060,3.051;P＞0.05）;对于34G＞A多态位点,携带GG基因型的胎盘标本平均mRNA及蛋白表达水平较携带AA基因型的胎盘标本高,且差异均有统计学意（q=3.540,4.720; P＜0.05）,而携带GA基因型的胎盘标本,其平均mRNA及蛋白表达水平分别与携带其他2种基因型的胎盘标本比较,其差异均无统计学意义（P＞0.05）.结论 421C＞A多态位点对人胎盘ABCG2基因mRNA及蛋白的表达无影响,而34G＞A多态位点对人胎盘ABCG2基因mRNA及ABCG2蛋白（BCRP）的表达均有影响.     

In vitro 3-dimensional tumor model for radiosensitivity of HPV positive OSCC cell lines

The incidence of oropharyngeal squamous cell carcinoma (OSCC) is increasing due to the rising prevalence of human papillomavirus (HPV) positive OSCC. HPV positive OSCC is associated with better outcomes than HPV negative OSCC. Our aim was to explore the possibility that this favorable prognosis is due to the enhanced radiosensitivity of HPV positive OSCC. HPV positive OSCC cell lines were generated from the primary OSCCs of 2 patients, and corresponding HPV positive cell lines generated from nodal metastases following xenografting in nude mice. Monolayer and 3 dimensional (3D) culture techniques were used to compare the radiosensitivity of HPV positive lines with that of 2 HPV negative OSCC lines. Clonogenic and protein assays were used to measure survival post radiation. Radiation induced cell cycle changes were studied using flow cytometry. In both monolayer and 3D culture, HPV positive cells exhibited a heterogeneous appearance whereas HPV negative cells tended to be homogeneous. After irradiation, HPV positive cells had a lower survival in clonogenic assays and lower total protein levels in 3D cultures than HPV negative cells. Irradiated HPV positive cells showed a high proportion of cells in G1/S phase, increased apoptosis, an increased proliferation rate, and an inability to form 3D tumor clumps. In conclusion, HPV positive OSCC cells are more radiosensitive than HPV negative OSCC cells in vitro, supporting a more radiosensitive nature of HPV positive OSCC.     

Human Antibody Fragments Specific for the Epidermal Growth Factor Receptor Selected from Large Non-immunised Phage Display Libraries

Antibodies to EGFR have been shown to display anti-tumour effects mediated in part by inhibition of cellular proliferation and angiogenesis, and by enhancement of apoptosis. Humanised antibodies are preferred for clinical use to reduce complications with HAMA and HAHA responses frequently seen with murine and chimaeric antibodies. We have used depletion and subtractive selection strategies on cells expressing the EGFR to sample two large antibody fragment phage display libraries for the presence of human antibodies which are specific for the EGFR. Four Fab fragments and six scFv fragments were identified, with affinities of up to 2.2 nM as determined by BIAcore analysis using global fitting of the binding curves to obtain the individual rate constants (k_a and k_d). This overall approach offers a generic screening method for the identification of growth factor specific antibodies and antibody fragments from large expression libraries and has potential for the rapid development of new therapeutic and diagnostic reagents.