Abstract
Sublancin is a glycosylated antimicrobial peptide produced by Bacillus subtilis 168 possessing antibacterial and immunomodulatory activities. This study was aimed at investigating the effects of sublancin on immune functions and serum antibody titer in specific pathogen-free (SPF) broiler chickens vaccinated with Newcastle disease (ND) vaccine. For this purpose, 3 experiments were performed. Experiment 1: SPF broiler chicks (14 days old) were randomly allotted to 1 of 7 groups including a blank control (BC), vaccine control (VC), and 5 (3-7) vaccinated and sublancin supplemented at 5, 15, 30, 45, and 60 mg activity/L of water, respectively. Vaccinated groups (2-7) were vaccinated with ND vaccine by intranasal and intraocular routes at the 14th day. On 7, 14, 21, and 28 days post vaccination (dpv), the blood samples were collected for the determination of serum hemagglutination inhibition (HI) antibody titer. Experiment 2: SPF broiler chicks were divided into 1 of 3 groups, i.e., blank control (BC), vaccine control (VC), and sublancin treatment (ST). On 7, 14, and 21 dpv, the blood samples were collected for measuring HI antibody titer by micromethod. Experiment 3: the design of this experiment was the same as that of experiment 2. On 7 and 21 dpv, pinocytosis of peritoneal macrophages, B lymphocyte proliferation assay, measurement of CD4+ and CD8+ T cells, and serum cytokine quantitation were carried out. It was noted that sublancin promoted B lymphocyte proliferation, increased the proportion of CD8+ T lymphocyte subpopulations, and enhanced the antibody titer in broiler chickens. In addition, it was also observed that sublancin has the potential to induce the secretion of IFN-γ, IL-10, and IL-4. In conclusion, these findings suggested that sublancin could promote both humoral and cellular immune responses and has the potential to be a promising vaccine adjuvant.
Highlights
Infectious diseases, especially viral diseases, remain one of the most critical challenges in poultry industry partly due to the genetic variation of viruses or the inferior quality of the vaccines
On 21 dpv, the sublancin treatments with 30 and 60 mg activity/L of water significantly increased (P < 0:05) the antibody titer compared with the vaccine control (VC) group
A numerical increase in antibody titer was observed in the 5 sublancin treatments compared with the VC group on 7, 14, and 28 dpv, there was no statistical difference
Summary
Infectious diseases, especially viral diseases, remain one of the most critical challenges in poultry industry partly due to the genetic variation of viruses or the inferior quality of the vaccines. A number of studies pointed out that AMPs participate in the modulation of the immune response [4, 5]. These immunopotentiating properties of AMPs make them a suitable candidate for the adjuvant design. Intragastric administration of sublancin induced a mixed immune response of Th1 and Th2 in ovalbumin-immunized mice [9]. These reports elucidated that sublancin could be a promising immunomodulator
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
