Differential regulation of apoptotic cell death in senescent human cells

Aging of human cells can be reproduced in monolayer cultures, revealing the phenotype of replicative senescence. It was shown that diploid human fibroblasts enter a stable growth arrest phenotype at the end of their lifespan and, in particular, these cells are resistant to various apoptotic stimuli. In contrast, human endothelial cells from the umbilical vein (HUVEC) acquire a proapoptotic phenotype when reaching senescence and this probably results from reactive oxygen species (ROS) induced damage and associated signaling. Ceramides were shown to accumulate in senescent fibroblasts and are also known as potent regulators of apoptotic cell death. To further study age-associated changes in proneness to apoptosis between fibroblasts and endothelial cells, both cell types were challenged by administration of exogenous ceramide and apoptotic cell death was determined. While ceramide can efficiently induce apoptosis in both young and senescent cells of either histotype, quantitative evaluation of the data show that senescent fibroblasts are more resistant to apoptosis induction when compared to their young counterparts, whereas in the case of endothelial cells proneness for apoptosis is increased in senescent cells. Together, these data suggest significant differences in the regulation of apoptosis associated with senescence in fibroblasts and endothelial cells.     

Decreased ATP-sensitive K(+) current density during chronic human atrial fibrillation

Chronic atrial fibrillation (AF) is associated with shortening of action potential duration (APD), which involves modified activity of atrial ion currents. However, little is known about the activity of ATP-sensitive K(+) channels (I(K,ATP)) during chronic AF. An AF-related increase in the activity of I(K,ATP) would reduce APD and could contribute to initiation and/or perpetuation of AF. Here, we studied the activity of I(K,ATP) in atrial myocytes from patients with sinus rhythm (SR) and chronic AF. Human atrial myocytes were isolated from atrial tissue obtained from patients undergoing open-heart surgery. Inward rectifier currents were measured with the whole-cell patch-clamp technique by applying a depolarizing ramp pulse (1245 ms) from -100 to +40 mV (0.5 Hz). I(K,ATP) was activated with the I(K,ATP) channel opener rilmakalim. The inward rectifier I(K1) and I(K,ATP) were identified by their sensitivity to 1 mM Ba(2+). Density of I(K1) did not differ between cells from patients with AF (at -100 mV: -14.8 +/- 1.3 pA/pF, n = 38/10 (cells/patients)) and SR (-13.8 +/- 1.5 pA/pF, n = 33/16). In both types of cells, rilmakalim stimulated I(K,ATP) (defined as rilmakalim-inducible current) in a concentration-dependent manner (0.3-10 microM). However, maximum activation of I(K,ATP) with 10 microM rilmakalim was smaller in AF than in SR cells (at -100 mV: -5.3 +/- 0.8 pA/pF, n = 22/7 vs. -11.2 +/- 2.9 pA/pF, n = 19/9; at +40 mV: +9.6 +/- 2.1 pA/pF, n = 22/7 vs. +23.7 +/- 3.4 pA/pF, n = 19/9 for AF and SR, respectively; P < 0.05). Only aortic valve disease and pulmonary hypertension were found to be independent contributors to I(K,ATP) current density. We provide evidence that chronic AF is associated with a downregulation of ATP-sensitive K(+) currents. These changes may provide an additional molecular mechanism for electrical remodeling in chronic AF.     

Differential coupling of m-cholinoceptors to Gi/Go-proteins in failing human myocardium

Muscarinic acetylcholine receptors (mAChRs) mediate their main cardiac effects via pertussis toxin-sensitive G-proteins. Physiological effects differ considerably between atrium and ventricle, and it is unknown to which extent these differences derive from selective receptor-G-protein coupling or further downstream events. We have characterized specific coupling between mAChRs and Gi/Go-protein isoforms in atrial and ventricular myocardium by agonist-dependent photoaffinity labeling with [(32)P]azidoanilido GTP (aaGTP) and immunoprecipitation in sarcolemmal membranes from terminally failing human hearts. The total amount of mAChRs, as determined by specific binding of [(3)H]QNB, was significantly higher in right-atrial (RA +/- SEM, 959 +/- 68 fmol/mg, n = 4) than in left-ventricular membranes (LV, 582 +/- 53 fmol/mg, n = 6). Standardized immunoblots revealed that Gialpha-2 was the predominant subtype in both regions. A 40-kDa splice variant of Goalpha (Goalpha-1 and/or Goalpha-3) was almost exclusively detectable in RA. Levels of Gialpha-3 and a 39-kDa splice variant of Goalpha (Goalpha-2) were also higher in RA. Basal aaGTP binding was higher in RA than in LV for all Gialpha/Goalpha subtypes. The carbachol (10 micromol/l)-induced increase in aaGTP binding was significantly higher in RA than in LV for Goalpha-1/3 (336 +/- 95% of LV, n = 4) and for Gialpha-3 (211 +/- 83%), lower for Gialpha-2 (42 +/- 5%), and was similar in both regions for Goalpha-2 (130 +/- 62%). The differential coupling of mAChRs in human RA and LV suggests that the initiation of different physiological responses to mAChR stimulation starts with signal sorting at the receptor-G-protein level.     

New approaches to understanding the immune response to vaccination and infection

The immune system is a network of specialized cell types and tissues that communicates via cytokines and direct contact, to orchestrate specific types of defensive responses. Until recently, we could only study immune responses in a piecemeal, highly focused fashion, on major components like antibodies to the pathogen. But recent advances in technology and in our understanding of the many components of the system, innate and adaptive, have made possible a broader approach, where both the multiple responding cells and cytokines in the blood are measured. This systems immunology approach to a vaccine response or an infection gives us a more holistic picture of the different parts of the immune system that are mobilized and should allow us a much better understanding of the pathways and mechanisms of such responses, as well as to predict vaccine efficacy in different populations well in advance of efficacy studies. Here we summarize the different technologies and methods and discuss how they can inform us about the differences between diseases and vaccines, and how they can greatly accelerate vaccine development.     

Risk of spontaneous abortion and other pregnancy outcomes in 15–25 year old women exposed to human papillomavirus-16/18 AS04-adjuvanted vaccine in the United Kingdom

BackgroundWe assessed the risk of spontaneous abortion (SA) after inadvertent exposure to HPV-16/18-vaccine during pregnancy using an observational cohort design.MethodsThe study population included women aged 15–25 years registered with the Clinical Practice Research Datalink General Practice OnLine Database in the United Kingdom (UK), who received at least one HPV-16/18-vaccine dose between 1st September 2008 and 30th June 2011. Exposed women had the first day of gestation between 30 days before and 45 days (90 days for the extended exposure period) after any HPV-16/18-vaccine dose. Non-exposed women had the first day of gestation 120 days–18 months after the last dose. SA defined as foetal loss between weeks 1 and 23 of gestation (UK definition).ResultsThe frequency of SA was 11.6% (among 207 exposed) and 9.0% (632 non-exposed), women: hazard ratio (HR) adjusted for age at first day of gestation 1.30 (95% confidence interval: 0.79–2.12). Sensitivity analysis per number of doses administered (−30 to +45-day risk period) showed a HR for SA of 1.11 (0.64–1.91) for 18/178 women with one dose during the risk period versus 2.55 (1.09–5.93) in 6/29 women with two doses within a 4–5 weeks period. The proportion of pre-term/full-term/postterm deliveries, small/large for gestational age infants, and birth defects was not significantly different between exposed and non-exposed women. Results were consistent using a (United States) SA definition of foetal loss between weeks 1–19 and/or the extended risk period.ConclusionThere was no evidence of an increased risk of SA and other adverse pregnancy outcomes in young women inadvertently HPV-16/18-vaccinated around gestation. Nevertheless, women who are pregnant or trying to become pregnant are advised to postpone vaccination until completion of pregnancy.     

Evaluation of anthrax vaccine safety in 18 to 20 year olds: A first step towards age de-escalation studies in adolescents

Background/objectivesAnthrax vaccine adsorbed (AVA, BioThrax^®) is recommended for post-exposure prophylaxis administration for the US population in response to large-scale Bacillus anthracis spore exposure. However, no information exists on AVA use in children and ethical barriers exist to performing pre-event pediatric AVA studies. A Presidential Ethics Commission proposed a potential pathway for such studies utilizing an age de-escalation process comparing safety and immunogenicity data from 18 to 20 year-olds to older adults and if acceptable proceeding to evaluations in younger adolescents. We conducted exploratory summary re-analyses of existing databases from 18 to 20 year-olds (n = 74) compared to adults aged 21 to 29 years (n = 243) who participated in four previous US government funded AVA studies.MethodsData extracted from studies included elicited local injection-site and systemic adverse events (AEs) following AVA doses given subcutaneously at 0, 2, and 4 weeks. Additionally, proportions of subjects with ≥4-fold antibody rises from baseline to post-second and post-third AVA doses (seroresponse) were obtained.ResultsRates of any elicited local AEs were not significantly different between younger and older age groups for local events (79.2% vs. 83.8%, P = 0.120) or systemic events (45.4% vs. 50.5%, P = 0.188). Robust and similar proportions of seroresponses to vaccination were observed in both age groups.ConclusionsAVA was safe and immunogenic in 18 to 20 year-olds compared to 21 to 29 year-olds. These results provide initial information to anthrax and pediatric specialists if AVA studies in adolescents are required.     

Human papillomavirus vaccine uptake in boys and girls in a school-based vaccine delivery program in Prince Edward Island,Canada

BackgroundIn 2013, Prince Edward Island was the first province to introduce HPV vaccine universally to grade six boys in a school-based program. Because uptake rates in boys are unknown in this type of vaccination program, uptake of HPV vaccination in boys was measured and compared with uptake rates in girls and then analyzed with factors such as county, urban–rural location of the school, and school board to identify where the vaccine program could be improved.MethodsHPV vaccination records from the provincial childhood immunization registry in PEI were merged with Department of Education data containing all grade six girls and boys in PEI. Vaccine uptakes between years and between sexes were compared using two sample tests of proportions. Logistic regression modeling which accounted for the hierarchical nature of the data was used to analyze associations between factors and uptake rates.ResultsAlthough uptake was high in boys and girls, a significantly greater proportion of girls (85%) received all three doses of the HPV vaccine compared to boys (79%; p = 0.004). The odds of grade six girls being fully vaccinated for HPV were 1.5 times greater than of grade six boys, and the odds of students in the English Language School Board receiving all three doses were more than twice as great as the odds of French Language School Board students.ConclusionsHPV vaccination for boys in PEI has had a successful launch, almost reaching the Canadian Immunization Committee recommendations of >80% for the early years of a program. PEI has a highly organized Public Health Nursing program that is involved in all childhood and school-based vaccinations in PEI and in this context very high coverage rates were obtained. Areas to target for improving uptake include the boys and the students in the French Language School Board.     

子宫腺肌症患者在位与异位内膜组织中rIL-10诱导下HLA-G的表达变化分析

目的:分析子宫腺肌症患者在位与异位内膜组织中rIL-10诱导下HLA-G的表达变化,探讨其临床意义.方法:选取该科2013年3 ～ 10月收治的子宫腺肌症患者中符合研究需求的在位子宫内膜组织与异位子宫内膜组织各52例,选取同时期收治的子宫腺肌症以外的其他子宫良性疾病患者子宫内膜52例设为对照组,进行rIL-10诱导处理后,运用免疫显色法测定HLA-G的阳性表达及其程度,通过内膜组织染色的深浅程度和存在染色反应的细胞数占总细胞数的比例进行综合评分.结果:研究组在位与异位内膜的HLA-G阳性率相对对照组均有较大变化,差异具有统计学意义(P＜0.05);而研究组在位内膜和研究组异位内膜之间及增生期和分泌期之间的HLA-G阳性率差异无统计学意义(P＞0.05).结论:检测rIL-10诱导下HLA-G的异常表达可提示发生子宫腺肌症的高危人群,建议临床推广使用.     

β-hCG、TGF-β和TβR-Ⅰ在卵巢上皮性癌中的表达及意义

目的:探讨人绒毛膜促性腺激素β亚单位(β-hCG)、转化生长因子β亚单位(TGF-β)及转化生长因子β亚单位受体Ⅰ (TβR-Ⅰ)在卵巢上皮性癌中的表达及临床意义.方法:选取2008年1月～2014年1月在石河子大学医学院第一附属医院以手术切除为初次治疗的卵巢上皮性癌石蜡标本60例、卵巢良性肿瘤组织标本40例和正常卵巢组织20例,采用免疫组化法检测β-hCG、TGF-β及TβR-Ⅰ的表达情况.结果:与卵巢良性肿瘤组织和正常卵巢组织相比,卵巢上皮性癌组织中β-hCG、TGF-β和TβR-Ⅰ的阳性表达率均明显升高,差异有统计学意义(P＜0.05);卵巢上皮性癌组织中β-hCG的阳性表达率与其手术病理分期及病理类型密切相关(P＜0.05),而TβR-Ⅰ及TGF-β的阳性表达率与病理类型密切相关(P＜0.05);β-hCG与TGF-β及TβR-Ⅰ的阳性表达率均呈负相关(r=-0.568,P＜0.01;r=-0.673,P＜0.01),TGF-β与TβR-Ⅰ的阳性表达率无相关性(r=0.128,P＞0.01).结论:β-hCG、TGF-β和TβR-Ⅰ对卵巢良性肿瘤和卵巢上皮性癌的鉴别诊断具有一定的临床意义.