Cloning and expression of single-chain Fv antibodies against H5N1 Avian influenza virus hemagglutinin / 病毒学报

To construct Fv antibodies against H5N1 Avian influenza virus hemagglutinin,extracted mRNA from B lymphoblastoid cell lines secreting anti-HA antibodies was used and the VH and VL genes were amplified by RT-PCR and linked together by splicing overlap extension (SOE) with (Gly4 Ser)3 linker. The recombinant plasmid was then transformed to E. coli BL21(DE3) and sequence analysis indicated the total length of scFv was 714 bp and the expression of Fv was validated by PAGE and Western blot.

Isolation and identification of a canine coronavirus strain from giant pandas (Ailuropoda melanoleuca)

Two giant pandas (Ailuropoda melanoleuca) died of unknown causes in a Chinese zoo. The clinical disease profile suggested that the pandas may have suffered a viral infection. Therefore, a series of detection including virus isolation, electron microscopy, cytobiological assay, serum neutralization and RT-PCR were used to identify the virus. It was determined that the isolated virus was a canine coronavirus (CCV), on the basis of coronavirus, neutralization by canine anti-CCV serum, and 84.3% to 100% amino acid sequence similarity with CCV. The results suggest that the affected pandas had been infected with CCV.

Emergency prophylactic effects of the avian influenza virus immunized serum on the infected mice / 中华预防医学杂志

<p><b>OBJECTIVE</b>To evaluate emergency prophylactic effects of the avian influenza virus immunized serum on experimentally infected mice.</p><p><b>METHODS</b>Serum HI antibody titers of 30 mice were detected at day 1 to 19 after being inoculated with 0.2 ml immune serum to estimate half life of immune serum. Ten mice clinical symptom was recorded to estimate the serum security after mice injected 1.5 ml immune serum. Seventy mice were randomly divided into 7 groups according to random number table and inoculated with 0.2 ml, 0.1 ml and 0.05 ml immune serum respectively via intraperitoneal injection on day 8, 4 and 1 prior to challenged with 10 LD(50) influenza virus intranasal. Mice were observed continually for 14 days to calculate the morbidity, mortality, average survival days and compare the lung index and viral titers in lung.</p><p><b>RESULTS</b>Serum HI antibody titers of mice which inoculated with 0.2 ml immune serum maintained 2(6) in 15 days after injection, but drawdown after day 17, the mice injected 1.5 ml immune serum were all alive and none onset. The survival rate of mice which injected 0.2 ml serum on the day 8, 4, 1 before challenge was 80%, 100% and 100%, and the average survival period was 13.1 days, 14.0 days and 14.0 days respectively. The survival rate of mice which injected 0.1 ml and 0.05 ml serum on day 1 before challenge was 100% and 50%, and the average survival days were 14.0 days and 11.7 days respectively. The mice lung index of experimental groups (0.0096 +/- 0.0033 - 0.0145 +/- 0.0060) was smaller than that of viral control group (0.0199 +/- 0.0025), with a statistical significance (P value 0.0022 - 0.0470, < 0.05). The viral titers in lung were significantly decreased by 2 titer as compared to the viral controls.</p><p><b>CONCLUSION</b>The avian influenza virus immunized serum might contain the emergency prophylactic effects and could be developed as an agent for possible human-avian influenza pandemic.</p>

Pathogenesis of H5N1 avian influenza virus in C57BL/6 mice / 病毒学报

C57BL/6 mice were inoculated intranasally (50 microl) with serial 10-fold dilution of HAB/01 H5N1 virus. Three and five days later, three mice of each group were euthanized. Lung injury was assessed by observation of lung histopathology, virus titers and MCD50 were also measured. Our data showed that H5N1 viral infection in mice resulted in mainly epithelial injury and interstitial pneumonia, featuring significant weight loss, dramatically increased lung wet weight:body weight ratio, inflammatory cellular infiltration, alveolar and interstitial edema, hemorrhage in lungs with high virus titers, and MCD50 was 10(-6.5)/ 0.05 mL. These results suggested that a mouse model of H5N1 viral infection was successfully established which may benefit study of H5N1 avian influenza virus and pathogenic mechanism of host.

Study on the histopathology of cats inoculated with H5N1 subtype high pathogenic avian influenza virus originated from tigers / 病毒学报

In this study, the HPAIV A/Tiger/Harbin/01/2002 (H5N1) used was originated from tigers and propagated in SPF embryonated hen eggs. TCID5, of the virus was 10(-7.36)/0. 05mL on MDCK cell. The cats were inoculated through bronchus route and then, the cats of dead and control were collected for histopathological and immunohistochemistry examination. Meanwhile, the emulsion supernatant fluid of organs and the pharyngeal swab samples of the dead cats were collected for RT-PCR, survived cats and the control cats were tested for the presence of HI antibody by standard method. The results indicated that the damage of lungs from the dead cats were most obvious, the wide range of red consolidation focus emerged on the lobus pulmonis, the fused focus of infection caused injury of lungs. Histology under the microscope revealed diffuse alveolar damage, confluence phlegmasia pathology, infiltration of lymphomonocytes, sackful of infiltration of macrophages and manipulus protein-like effusion in the alveolar. By immunohistochemistry, the positively stained virus particles were found on the epithelial cells of bronchus and alveolus, and also in the endochylema of lymphomonocytes. The specific electophoretic band of 464bp amplified by RT-PCR from samples of pharyngeal swabs, lungs, kidneys, hearts and brains was as same as the theory value. HI antibody titers of the survived cat were 1:32.

Significance and Assaying of Serum Interleukin-1?,Interleukin-6,Interleukin-8 and Tumor Necrosis Factor-? in Highly Pathogenic Avian Influenza Viral Pneumonia in Mice / 实用儿科临床杂志

Objective To study the interrelation between highly pathogenic avian influenza viral pneumonia(HPAIVP) and cellular factors interleukin-1?(IL-1?),interleukin-6(IL-6),interleukin-8(IL-8)and tumor necrosis factor-?(TNF-?) in HPAIVP.Me-thods Sixty Kunming mice were divided into 2 groups randomly:experiment group and control group,each group consisted of 30 mice.The highly pathogenic avian influenza virus was used to establish HPAIDP models.The expressions of serum IL-1?,IL-6,IL-8 and TNF-? in experiment group of different moment and control group were detected by enzyme linked immunosorbent assay(ELISA).Result The levels of serum IL-1?,IL-6 and TNF-? in experiment group were significantly higher than those in control group(Pa

ISOLATION AND IDENTIFICATION OF XJ STRAIN OF CANINE DISTEMPER VIRUS / 微生物学通报

A canine distemper virus strain was isolated from the lung of dog coming from Aksu in Xing Jiang using lung primary M cell during the CDV molecular epidemiological study. It was demonstrated to be a virulent strain of CDV by a series of systematic identification such as morphology , serology neutralization test, canine infection test, and molecular virology test.