Apoptosis ; physiology ; Cells, Cultured ; DNA, Viral ; blood ; Epithelial Cells ; cytology ; virology ; Female ; Hepatitis B virus ; pathogenicity ; Hepatitis B, Chronic ; virology ; Humans ; Kidney Tubules ; cytology ; virology ; Male ; Serum

Epstein-Barr virus (EBV) is a human herpesvirus associated with important human diseases, including infectious mononucleosis syndrome, malignant lymphoma, and nasopharyngeal carcinoma. The mechanism of EBV entry into host cells remains a subject of intensive research. After decades of study, researchers have identified several key proteins and different patterns of EBV intrusion into host cells. The viral surface glycoproteins, gp350/220, gp42, gB, gH, and gL, are involved in interactions with the CR2 receptor on the surface of B lymphocytes during viral entry. However, the majority of epithelial cells lack CR2 receptor expression, which makes viral invasion much more complex than in B lymphocytes. Three different models have been proposed to explain how EBV enters epithelial cells: (1) "transfer of infection", mediated by B lymphocytes or Langerhans cells; (2) EBV utilizes its own proteins during the process of fusion with the cell membrane; and (3) progeny virions arising from EBV-infected epithelial cells cross lateral membranes into adjacent epithelial cells. This review will discuss the relevant mechanism of viral entry into B lymphocytes and epithelial cells during EBV infection.
Animals ; B-Lymphocytes ; virology ; Epithelial Cells ; virology ; Epstein-Barr Virus Infections ; virology ; Herpesvirus 4, Human ; genetics ; physiology ; Humans ; Viral Proteins ; genetics ; metabolism ; Virus Internalization

Respiratory virus poses a serious threat to human life and health. Airway epithelial cells are the body's first line of defense from a wide variety of foreign pathogens, such as viruses and bacteria. Therefore, successful airway epithelial cell culture can provide a model for investigating the mechanisms underlying respiratory pathogenic diseases following airway virus infection. This respiratory disease model can also be used for the potential development of novel therapeutics. Here we provide a brief review of recent developments on the culture of cells derived from human trachea-bronchial airway epithelium, and the application of this model for studying respiratory virus and disease.
Animals ; Cell Culture Techniques ; Epithelial Cells ; virology ; Humans ; Respiratory Tract Diseases ; virology ; Virus Diseases ; virology ; Virus Physiological Phenomena ; Viruses ; genetics ; isolation & purification

Cell Line, Transformed ; Cell Transformation, Viral ; DNA, Viral ; genetics ; Epithelial Cells ; cytology ; virology ; Human papillomavirus 16 ; genetics ; Humans ; Plasmids

OBJECTIVETo observe the biological changes of primary human nasopharyngeal epithelial cells in the early stage of immortalization.

METHODSThe morphological changes of nasopharyngeal epithelial cells were observed by phase contrast microscopy, and the activity profile of senescence-associated beta-galactosidase (SA-beta-Gal) was detected by SA-beta-Gal staining. The expression of p16(INK4a) protein was tested by immunochemical assay, and the life span in vitro of nasopharyngeal epithelial cells was calculated as population doublings. In addition, the expression of Epstein-Barr (EB) virus latent membrane protein 1 (LMP1) was also detected by immunofluorescence staining.

RESULTSMorphologically, cells treated with EB virus and 12-o-tetradecanoyl-phorbol-13-acetate (TPA) formed multi-layer foci, and their cellular life span in vitro was extended (about 155 days of culture). A low percentage of cells (about 4.8%) expressed SA-beta-Gal activity at late primary culture, and did not always express p16(INK4a) protein in the progression of culture.

CONCLUSIONSNasopharyngeal epithelial cells treated with EB virus in cooperation with TPA can pass through the stage of senescence and enter the early stage of immortalization. Some changes of phenotype occur in these cells. Our results provide data for further studying the mechanism of immortalization and the establishment of a human nasopharyngeal epithelial cell line.

Cell Transformation, Viral ; Cellular Senescence ; Cyclin-Dependent Kinase Inhibitor p16 ; analysis ; Epithelial Cells ; physiology ; virology ; Herpesvirus 4, Human ; physiology ; Humans ; Nasopharynx ; cytology ; virology ; Tetradecanoylphorbol Acetate ; pharmacology

OBJECTIVETo investigate the Epstein-Barr virus (EBV) BamH I "f" variant in primary nasopharyngeal carcinoma (NPC) and its metastases in lymph nodes (LN).

METHODSIn situ hybridization was used to detect EBV-encoded small RNA (EBER) expression in 21 paired paraffin-embedded tissue from primary NPC and their lymph node metastases and 22 primary NPC without lymph node metastasis. PCR and restriction fragment length polymorphism (RFLP) assay were used to detect EBV BamH I "f" variant in all cases of NPCs, lymph node metastases and 50 cases of chronic inflammation of nasopharynx from Canton.

RESULTSAll cases of NPCs and their lymph node metastases showed EBER expression, indicating a high EBV-positive rate in Cantonese NPC patients. EBV BamH I "f" variant was found in 11 cases (52.4%, 11/21) of primary NPCs with LN metastasis, 12 cases (57.1%, 12/21) of the LN metastases, and 18 cases (81.8%, 18/22) of primary NPCs without LN metastasis. However, of the 50 cases of chronic inflammation of nasopharynx, only one case (2.1%, 1/47) demonstrated BamH I "f" variant. The frequency of BamH I "f" variant in NPC was therefore dramatically higher than that in chronic inflammation of nasopharynx. It is of note that atypical hyperplasia was observed in a few epithelial cells from the case of chronic inflammation of nasopharynx expressing BamH I "f" variant.

CONCLUSIONSThe frequency of EBV BamH I "f" variant in NPC is significantly higher than that in chronic inflammation of nasopharynx. It is the first demonstration that the BamH I "f" variant is also present in the LN metastases of NPC. The frequency of BamH I "f" variant in metastatic NPC of the lymph node is almost equal to that of primary NPCs.

Epithelial Cells ; drug effects ; Epstein-Barr Virus Infections ; classification ; complications ; virology ; Herpesvirus 4, Human ; classification ; genetics ; Humans ; In Situ Hybridization ; Lymph Nodes ; drug effects ; pathology ; virology ; Lymphatic Metastasis ; physiopathology ; Nasopharyngeal Neoplasms ; genetics ; pathology ; virology ; Nasopharynx ; virology ; RNA, Viral ; analysis ; pharmacology

In this study, apoptosis was induced by new type gosling viral enteritis virus (NGVEV) in experimentally infected goslings is reported in detail for the first time. After 3-day-old goslings were orally inoculated with a NGVEV-CN strain suspension, the time course of NGVEV effects on apoptotic morphological changes of the internal tissues was evaluated. These changes were observed by histological analysis with light microscopy and ultrastructural analysis with transmission electron microscopy. DNA fragmentation was assessed with a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and DNA ladder analysis. A series of characteristic apoptotic morphological changes including chromatin condensation and margination, cytoplasmic shrinkage, plasma membrane blebbing, and formation of apoptotic bodies were noted. Apoptosis was readily observed in the lymphoid and gastrointestinal organs, and sporadically occurred in other organs after 3 days post-infection (PI). The presence and quantity of TUNEL-positive cells increased with infection time until 9 days PI. DNA extracted from the NGVEV-infected gosling cells displayed characteristic 180~200 bp ladders. Apoptotic cells were ubiquitously distributed, especially among lymphocytes, macrophages, monocytes, and epithelial and intestinal cells. Necrosis was subsequently detected during the late NGVEV-infection phase, which was characterized by cell swelling, plasma membrane collapse, and rapidly lysis. Our results suggested that apoptosis may play an important role in the pathogenesis of NGVE disease.
*Adenoviridae/classification/pathogenicity ; Adenoviridae Infections/pathology/*veterinary/virology ; Animals ; *Anseriformes ; *Apoptosis ; Bird Diseases/*virology ; DNA Fragmentation ; Enteritis/*veterinary/virology ; Epithelial Cells/cytology/virology ; In Situ Nick-End Labeling ; Intestines/cytology/virology ; Leukocytes/cytology/virology ; Lymphoid Tissue/cytology/virology ; Macrophages ; Microscopy, Electron, Transmission

OBJECTIVETo observe the influence of Wnt-1 recombinant adenovirus on differentiation tendency of human epidermal stem cells.

METHODSWnt-1 recombinant adenovirus was transduced into hESCs (E group), while normal hESCs were used as control (C) group. The diameter, proliferation,and labeling molecular expression of hESC were determined. The content of MMP-2 and MMP-7 in supernate were also assayed.

RESULTSThere was no obvious difference in diameter of hESC between two groups. The density of hESC in E group was (1.45 +/- 0.09) x 10(5)/mL, which was obviously higher than that in C group [(1.18 +/- 0.10) x 10(5)/mL, P < 0.05]. There were no obvious differences in expression of markers between two groups,including keratin 5 (KS), K6, K7, KS, K14, CD44, carcinoembryonic-like antigen (CEAA), ER, PR (P > 0.05) ,while the expression of K 10 was different among groups [(60 +/- 3)% in E group, 0 in C group], also K18 [(34.3 +/- 2.1)% in E group vs. (13.8 +/- 1.7)% in C group, P < 0.05], and K19 [(17.1 +/- 1.8)% in E group vs. (24.4 +/- 1.5)% in C group, P < 0.05].The contents of MMP-2 and MMP-7 in E group were higher than those in C group (P < 0.01).

CONCLUSIONWnt-1 recombinant adenovirus can induce the differentiation of hESCs to glandular epithelium-like cells.

Adenoviridae ; genetics ; Cell Differentiation ; Cell Line ; Epithelial Cells ; cytology ; virology ; Humans ; Matrix Metalloproteinase 2 ; metabolism ; Matrix Metalloproteinase 7 ; metabolism ; Stem Cells ; cytology ; Wnt1 Protein ; genetics

Avian influenza virus subtype H9N2 has been circulating in multiple terrestrial birds and repeatedly infecting mammals, including swines and humans to pose a significant threat to public health. The cross-species infection of human, replication activity and tissue tropism of avian influenza virus H9N2 was evaluated in this study. The results showed that surgically removed human lung tissue samples were infected ex vivo by avian influenza virus subtype H9N2 (Ck/GX/1875/04, Ck/GX/187/05) and seasonal human influenza virus H3N2 (A/ST/602/05). Examination of nucleoprotein expression replication in the infected human lung tissue samples showed that the replication of avian influenza virus H9N2 and seasonal human influenza virus H3N2 were mainly prevalent in alveolar epithelial cells, respiratory bronchiole epithelial cells and bronchial epithelial cells. Double-immunostaining for viral antigens and cellular markers indicated that avian influenza virus subtype H9N2 replicated in type 2 alveolar epithelial cells. These findings suggest that the H9N2 virus may be better adapted to the human host and replicates efficiently in human lung epithelial cells. Moreover, H9N2 avian influenza virus repeatedly infecting human, may favor gene evolution and the potential emergence of pandemic influenza virus.
Animals ; Epithelial Cells ; virology ; Humans ; Influenza A Virus, H3N2 Subtype ; genetics ; physiology ; Influenza A Virus, H9N2 Subtype ; genetics ; isolation & purification ; physiology ; Influenza, Human ; virology ; Lung ; cytology ; virology ; RNA-Binding Proteins ; genetics ; metabolism ; Viral Core Proteins ; genetics ; metabolism ; Virus Replication

OBJECTIVETo investigate the effects of human cytomegalovirus (HCMV) on the proliferation of duct epithelial cells of human salivary gland (HSG).

METHODSThe expression of proliferating cell nuclear antigen (PCNA) and p53 were studied in 11 cases of parotid cytomegalic inclusive disease (PCID) using immunohistochemical staining method. The effects of human cytomegalovirus (HCMV) on the proliferation of HSG were investigated by MTT method in vitro. The expression of PCNA in HSG infected by HCMV was examined using immunocytochemical staining and Western blotting.

RESULTSPCNA was expressed weakly in most of megalic inclusion cells which were positive for HCMV, while all the megalic inclusion cells were p53 negative in all 11 cases of PCID. HCMV inhibited proliferation of HSG in vitro in a time dependent and dose dependent manner. Down-regulation of PCNA was shown in infected cells.

CONCLUSIONHCMV inhibits proliferation of HSG and down-regulation of PCNA may be an expression of the inhibition.

Cell Division ; Cells, Cultured ; Cytomegalovirus ; genetics ; pathogenicity ; physiology ; Cytomegalovirus Infections ; genetics ; pathology ; Down-Regulation ; Epithelial Cells ; pathology ; Female ; Humans ; Male ; Parotid Gland ; pathology ; virology ; Proliferating Cell Nuclear Antigen ; analysis ; Salivary Ducts ; pathology ; virology ; Tumor Suppressor Protein p53 ; analysis