Induction of intestinal immune response to lentogenic vaccine strain of newcastle disease virus in chicken

Mucosal surface provide portal entry for a majority of infectious agents. Hence, protection at the mucosal surface through immunization plays an important role in containing its systemic spread. Mucosal vaccination of chicken at early stages of life with live attenuated strain of Newcastle disease virus (NDV) induces both cellular and humoral immune responses against the Newcastle disease. In order to characterize the mucosal immune response elicited by live virus in chicken, the presence of specific antibodies in intestinal secretions of immunized birds was evaluated. The proliferative response of Intraepithelial Lymphocytes (IELs) and cytotoxicity of IELs against xenogenic targets were also evaluated. The IEL proliferation and cytotoxicity remained un-influenced by the vaccination of chicks with live F strain of NDV. Intranasal and oculonasal route of vaccination induced virus specific IgG and IgA in the intestinal secretions, however, at 7 weeks post vaccination the IgG levels were greatly reduced and IgA levels were undetectable.