Anti-NDV Monoclonal antibody, Clone C535M

Newcastle disease virus (NDV) causes significant economic losses to the poultry industry worldwide. As a lymphoid organ, the bursa of Fabricius (BF) plays a pivotal role in destroying invading pathogens. Virulent NDV strains can cause rapid atrophy of the BF; however, there is limited knowledge regarding the BF innate immune response to NDV infection. In this study, we used the virulent NDV strain F48E9 to infect four-week-old chickens and found atrophy of the BF, with severe damage and high NDV viral loads after NDV infection in dying chickens. To better understand the interactions between the host and NDV, we compared the transcriptional profiles at 48 and 72 h following infection with the virulent NDV strain F48E9 using RNA-seq. We identified a total of 1498 differentially expressed genes (DEGs), which were enriched in a variety of biological processes and pathways according to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. The enriched pathways were associated with innate immune and inflammatory responses as well as metabolism-related signalling pathways. Excessive inflammatory and innate immune responses induced by the NDV strain may be related to severe BF damage. The global survey of changes in gene expression performed herein provides new insights into complicated molecular mechanisms underlying the interaction between NDV and chickens and will enable the use of new strategies to protect chickens against NDV.

Newcastle disease virus (NDV) and H9N2 subtype Avian influenza virus (AIV) are two notorious avian respiratory pathogens that cause great losses in the poultry industry. Current inactivated commercial vaccines against NDV and AIV have the disadvantages of inadequate mucosal responses, while an attenuated live vaccine bears the risk of mutation. Dendritic cell (DC) targeting strategies are attractive for their potent mucosal and adaptive immune-stimulating ability against respiratory pathogens. In this study, DC-binding peptide (DCpep)-decorated chimeric virus-like particles (cVLPs), containing NDV haemagglutinin-neuraminidase (HN) and AIV haemagglutinin (HA), were developed as a DC-targeting mucosal vaccine candidate. DCpep-decorated cVLPs activated DCs in vitro, and induced potent immune stimulation in chickens, with enhanced secretory immunoglobulin A (sIgA) secretion and splenic T cell differentiation. 40 mu g cVLPs can provide full protection against the challenge with homologous, heterologous NDV strains, and AIV H9N2. In addition, DCpep-decorated cVLPs could induce a better immune response when administered intranasally than intramuscularly, as indicated by robust sIgA secretion and a reduced virus shedding period. Taken together, this chimeric VLPs are a promising vaccine candidate to control NDV and AIV H9N2 and a useful platform bearing multivalent antigens.