The objective of the studies presented was to define a molecular basis for infectivity and pathogenicity of influenza virus. It is demonstrated that activation of the HA glycoprotein by post-translational proteolytic cleavage is indispensable for the formation of infectious influenza virus. There are two preconditions for influenza virus to be pathogenic: (1) the presence on the virus particle ...

conclusions after seven consecutive passages of both cell cultures, the h9n2 virus showed similar antigenicity, also no change on viral titer level and virus replication behavior in adaptation was found. the results highlighted the use of a549 cells for efficient virus isolation. results the influenza virus infectivity was not significant difference in these cells in the presence of trypsin. th...

Chicken anemia virus is commonly found in commercially produced chickens and has a worldwide distribution. It is difficult to inactivate thermally or with common disinfectants, which limits the utility of normal sanitization practices. The virus is important because of the disease it produces following transovarian transmission and because of its potential for inducing immunosuppression alone o...

To detect the molecules that interact with infectious bursal disease virus (IBDV), the chicken B lymphoblastoid cell line, LSCC-BK3, which is permissive for virulent IBDV infection was investigated. The sodium dodecyl sulfate-solubilized plasma membrane fraction from the cells was subjected to a virus overlay protein binding assay. The IBDV specifically bound to proteins in LSCC-BK3 plasma memb...

The objective of the studies presented was to define a molecular basis for infectivity and pathogenicity of influenza virus. It is demonstrated that activation of the HA glycoprotein by post-translational proteolytic cleavage is indispensable for the formation of infectious influenza virus. There are two preconditions for influenza virus to be pathogenic: (1) the presence on the virus particle ...

Trachea, lung, and conjunctive samples from 51 commercial layer farms from Bastos region, São Paulo, Brazil, were submitted to nestedPCR and virus isolation in SPF chicken embryos for ILT diagnosis. This region experienced an outbreak characterized by respiratory signs, decrease in egg production and increased mortality. Out of the 51 tested field samples, 23 were positive for ILT by nested-PCR...

Infectious bursal disease (also known as IBD, Gumboro Disease, Infectious Bursitis and Infectious Avian Nephrosis) is a highly contagious disease of young chickens caused by infectious bursal disease virus (IBDV), characterized by immunosuppression and mortality generally at 3 to 6 weeks of age. The disease was first discovered in the USA, near the town of Gumboro, Delaware in 1962. It is econo...

Ten temperature-sensitive mutants of Sendai virus, a paramyxovirus, were isolated and partially characterized. The mutants replicated in chicken embryo lung cells at 30 C, but not at 38 C; wild-type virus grew equally well at both temperatures. Complementation tests divided the mutants into seven groups. Six groups synthesized neither infectious virus nor RNA when incubated at 38 C from the beg...