Locally produced mucosal IgG in chickens immunized with conventional vaccines for Newcastle disease virus

Abstract

Newcastle disease virus (NDV) is the causative agent of an economically important disease, which affects all species of birds worldwide. Current vaccination programs for NDV include the use of either low-virulent live-virus vaccines or inactivated vaccines to induce protective immunity while producing minimal adverse effects in birds. In order to further characterize the immune response elicited by live virus and inactivated NDV conventional vaccines in chickens, we evaluated the presence of specific antibodies in different secretions and in tissue culture supernatants of immunized birds. To this end, we analyzed all the samples by ELISA, using an indirect assay set up in the laboratory. Specific anti-NDV IgG antibodies were detected in tracheal and cloacal swabs and tracheal and intestinal washes of immunized animals. We also found specific anti-NDV IgG antibodies in tracheal and intestinal tissue culture supernatants, indicating that the IgG found in swabs and washes was not transudated from serum or, at least, was not all transudated from serum. Knowledge about the mechanisms involved in the immune response of chickens to different NDV vaccines should increase our understanding of the mucosal response against the virus and, eventually, provide new useful information for the development and evaluation of synthetic vaccines.

Detection of immunoglobulins containing plasma cells in the thymus, bursa of Fabricius and spleen of vaccinated broiler chickens with Newcastle disease virus vaccine

“…The frequency of these cells and the antibody titre in the serum increased with the NDV vaccine alone [25] or perform synergistic effect with immune adjuvant [26]. In the present study, the number of IgG-and IgM-positive cells was statistically higher than IgA-positive cells in the thymus and bursa of Fabricius.…”

Preparation and Efficacy of a Live Newcastle Disease Virus Vaccine Encapsulated in Chitosan Nanoparticles

“…Current vaccination programs for ND include the use of lentogenic live-virus vaccines or inactivated vaccines to induce protective immunity while producing minimal adverse effects in chickens [3]. Inactivated oil-emulsion vaccines have poor immunogenicity and elicit a lower antibody response in the mucosal secretion by the single immunization.…”

Induction of Mucosal Humoral Immunity by Subcutaneous Injection of an Oil-emulsion Vaccine against <i>Salmonella enterica</i> subsp. <i>enterica</i> serovar Enteritidis in Chickens

“…IgA is involved in mucosal immunity in mammals and birds 8,9) . Pathogen-specific IgG antibody has been reported in the trachea and intestine in chickens following the stimulation of mucosal antibody producing cells by an inactivated Newcastle disease vaccine 10) . In this study, anti-SE IgG was found in the intestinal mucosa washings, but the secretion mechanism is not clear, and the ways in which IgG and IgA are secreted from human intestinal mucosa may differ 11) .…”