bacterin

Given the significant zoonotic threat posed by Salmonella enterica serovar Dublin (S. Dublin) and its substantial impact on animal populations and public health, the objective of the present study was to assess the immunogenicity and protectivity of subcutaneous administration of Salmonella Dublin bacterin in a murine model. 

Specific pathogen-free female BALB/c mice were tested for Salmonella-free status, and housed in controlled conditions. A formalin-killed bacterin was prepared from a local isolate of S. Dublin using a well-established protocol, ensuring bacterial inactivation and safety. Groups 1 through 3 of mice were received, respectively, either phosphate buffered saline plus alum or a single dose of inactivated bacterins with and without alum adjuvant via subcutaneous route. Immune responses were evaluated through microagglutination, enzyme-linked immunosorbent assay, delayed-type hypersensitivity, interferon-gamma assays, and challenge with viable S. Dublin.

Microagglutination and enzyme-linked immunosorbent assay tests revealed alum-adjuvanted injection as the best method for stimulation of anti-S. Dublin antibodies production. The gamma interferon production and delayed hypersensitivity tests, crucial for cellular immunity, were also most elevated in mice injected with alum-adjuvanted S. Dublin bacterin. After the challenge with the live bacteria, the isolation rate of S. Dublin was significantly different (P=0.03) among the different groups but only mice injected with alum-adjuvanted showed a significant difference (P≤0.05) compared to the control group.

This study emphasizes the efficacy of alum as an adjuvant in inactivated S. Dublin vaccines. Insights gained from both humoral and cellular immune responses, provide valuable knowledge for the development of S. Dublin vaccination strategies.

Bacterin-based vaccination may be a stressful condition, leading to harmful effects, such as high lipid peroxidation and telomere shortening. This study aimed to reduce these probable side effects via the administration of different concentrations of licorice (because of its anti-oxidative and anti-aging properties).

Japanese quails as animal models were reared for 42 days under standard conditions. The birds were divided into eight groups, including a control group, licorice treatments (licorice 0.02%, Licorice 0.04%, and licorice 0.08% groups), and Salmonella bacterin treatments (bacterin, bacterin+licorice 0.02%, bacterin+licorice 0.04%, and bacterin+licorice 0.08% groups). The Salmonella enterica bacterin-based vaccine was injected twice on days 14 and 28. Serum lipid peroxidation and telomere length of immune cells in all experimental groups were measured. 

Lipid peroxidation and telomere shortening enhanced following bacterin vaccination. Licorice at doses of 0.04%, 0.08%, or both reduced the lipid peroxidation and telomere shortening in non-vaccinated and vaccinated birds, while the dose of 0.02% was not effective.

This study confirmed the side effects of high lipid peroxidation and telomere attrition for S. enterica bacterin-based vaccination. Also, the improving properties of licorice for these side effects were considered to be effective.

Pasteurella multocida continues to pose a danger to prone farm and wild animals all over the world. Chemotherapeutic treatments are progressively losing their effectiveness, last for long time, and cost a lot of money, as well as being toxic to human consumers. Therefore, clearing the way for immunization as a big-wheel alternative against the economic grain. Yet, the vaccines available in the market do not confer the necessary protection against the pathogen. The integration of the well adjuvanted killed vaccine with the attenuated vaccines proved to offer an effective protection to the host animals. However, the bare use of the killed bacterin to provide protection from the possible harm of the live attenuated vaccine was doubtful.
In the present study, propolis extracts were used to ameliorate the immunogenicity of the Pasteurella bacterin. The cellular and humoral activities were assessed for the different bacterin formulations.
Propolis extracts adjuvants proved to broaden and extend the IgG potency, as well as to induce a unique mucosal protection against the bacterium. Simultaneously it offered an anti-inflammatory effect that increased the tolerability to the bacterin. While the cellular activity was relatively reduced with propolis extracts.
These results confirm the effectiveness of the formulation of the bacterin with propolis to offer a potent homologous primary protection to the animals against the long-life use of the attenuated Pasteurella vaccines.