Monitoring adenovirus infections with on-line and off-line methods

Several known process monitoring methods were tested for their efficacy in the detection of adenovirus infections. The methods that we explored include several indirect indications of viral infections, including metabolic rate analysis, secondary gauges of respiration, cell size measurement, cell number and cell viability determination, and changes in capacitance. Direct indications of the adenovirus infection were also applied, including total viral particle and infectious particle measurements, as well as a flow cytometry method for detecting infected cells. All of the methods tested in the study provide some positive indication of an adenovirus infection. Many of the methods require repeated sampling, which may limit their utility in a manufacturing process. All of the indirect measures of viral infection may be limited by the fact that they do not uniquely identify an infection. The simplest monitoring methods appear to be detection of changes in respiration or the capacitance of the culture, both of which seem to provide a clear indication of an infection. Further work will be required to demonstrate that these indications are characteristic of only a successful and productive adenovirus infection.     

Persistent adenovirus infections of nonpermissive monkey cells.

Persisten infections of monkey cells have been established by using two serotypes of human adenovirus. The persistently infected cells show no morpho logical changes, but continue ot produce low titers of infectious adenovirus. The inapparent infection can, at any time, be converted to a cytolytic productive one by superinfection with simian virus 40. Persistence in this system does not appear to result from multiple rounds of lytic infection, nor is it mediated by production of defective interfering particles. The persistently infected cells do not possess the characteristics of oncogenic transformation. Results of these studies also whow that the nonpermissiveness of monkey cells to adenovirus replication can be partially overcome by infection at high multiplicity.     

杭州地区腹泻儿童轮状病毒与腺病毒感染调查

目的 分析不同季节及不同年龄段腹泻患儿感染轮状病毒（RV）与腺病毒（Eads）情况,为临床提供早期、快速、准确、可靠的依据,以便及时采取相应的治疗使患儿早日康复。方法 采用杭州艾博医药有限公司提供的轮状病毒（A组）/腺病毒检测试剂盒（乳胶法）,对2012年1月至2015年12月浙江省人民医院门诊和住院就诊的3 368例腹泻儿童粪便标本进行轮状病毒和腺病毒抗原检测。结果 3 368例腹泻儿童粪便中,RV阳性578例占17.16%,Eads阳性106例占3.15%。11月至次年1月为轮状病毒感染的高发月份,1～3岁为儿童感染的高发年龄;腺病毒感染阳性率低,呈散发性。结论 杭州地区近年1～3岁婴幼儿的腹泻主要是由轮状病毒和腺病毒引起,其中轮状病毒感染率明显高于腺病毒,且有明显的季节性;而腺病毒感染呈散发流行,未表现出明显的季节性及年龄分布。     

Intact microtubules support adenovirus and herpes simplex virus infections

Capsids and the enclosed DNA of adenoviruses, including the species C viruses adenovirus type 2 (Ad2) and Ad5, and herpesviruses, such as herpes simplex virus type 1 (HSV-1), are targeted to the nuclei of epithelial, endothelial, fibroblastic, and neuronal cells. Cytoplasmic transport of fluorophore-tagged Ad2 and immunologically detected HSV-1 capsids required intact microtubules and the microtubule-dependent minus-end-directed motor complex dynein-dynactin. A recent study with epithelial cells suggested that Ad5 was transported to the nucleus and expressed its genes independently of a microtubule network. To clarify the mechanisms by which Ad2 and, as an independent control, HSV-1 were targeted to the nucleus, we treated epithelial cells with nocodazole (NOC) to depolymerize microtubules and measured viral gene expression at different times and multiplicities of infections. Our results indicate that in NOC-treated cells, viral transgene expression was significantly reduced at up to 48 h postinfection (p.i.). A quantitative analysis of subcellular capsid localization indicated that NOC blocked the nuclear targeting of Ad2 and also HSV-1 by more than 90% at up to 7 h p.i. About 10% of the incoming Texas Red-coupled Ad2 (Ad2-TR) was enriched at the nucleus in microtubule-depleted cells at 5 h p.i. This result is consistent with earlier observations that Ad2-TR capsids move randomly in NOC-treated cells at less than 0.1 micro m/s and over distances of less than 5 micro m, characteristic of Brownian motion. We conclude that fluorophore-tagged Ad2 and HSV-1 particles are infectious and that microtubules play a prominent role in efficient nuclear targeting during entry and gene expression of species C Ads and HSV-1.     

Early RNA of adenovirus type 3 in permissive and abortive infections.

Early adenovirus type 3 cytoplasmic polyadenylated RNAs from HeLa and BHK-21 cells were detected and mapped on the viral genome by gel blotting and hybridization techniques. The sizes and locations of the 16 adenovirus type 3 RNAs were identical in the two cell types, although relative molarities of the various RNA species differed. Each of the early adenovirus type 3 RNAs was associated with polysomes in both cell types, suggesting that the abortive infection of hamster cells does not result from a defect in early adenovirus type 3 mRNA biosynthesis. No RNAs from regions transcribed late in infection of permissive cells were detected in BHK-21 cells.     

Experimental study of combined staphylococcal, streptococcal and adenovirus infections in tissue culture]

Associated adenoviral, staphylococcus, and streptococcus infection was studied in the cultures of cells HEp-2 and PAO. Under conditions of monoinfection the cell culture largely inhibited the reproduction of staphylococci, and failed to influence the streptococci. In double and triple associated infections staphylococci overcame the inhibitory action of the cell culture. The pathogenic properties of cocci (plasma coagulation, hemotoxic properties) grown in the cell culture both under conditions of monoinfection, and in associations, failed to change. In double and triple associated infections adenoviruses did reproduce, but in lower titre than in monoinfection. Under conditions of mixed infection cocci penetrated and reproduced in the cell cytoplasm more intensively than in monoinfection. The cytopathic action was determined by viral associate, and was identical by its character to adenoviral monoinfection. A statistically significant increase in the activity of aldolase and transaminase enzymes was noted in mixed infection. The changes in the enzyme activity proved to depend on the character of the associations studied.