Comparison of the Immunogenicity of Different Proportions of Chitosan Adjuvant in Attenuated Neospora caninum Vaccine in BALB/c Mice

Articles in Press

Document Type : Research Article

Authors

Seyed Reza Hosseini ¹

Milad Hamzehali Tehrani ²

marzieh kefayat ³

Amir Hosein Norouzi ³

¹ Department of veterinary medicine, Shk. C. Islamic Azad University, Shahrekord, Iran.

² Department of Pathobiology, Faculty of Veterinary, Science and Research Branch, Islamic Azad University, Tehran, Iran.

³ Department of Pathobiology, Faculty of Veterinary, Karaj Branch, Islamic Azad University, Karaj, Iran.

10.22067/ijvst.2025.94043.1567

Abstract

Neosporosis is a neuromuscular infectious disease in dogs caused by the protozoan N. caninum. This disease is globally distributed; dogs and canines are the definitive hosts, while a wide range of animals serve as intermediate hosts. Therefore, this study aimed to compare the immunogenicity of different proportions of chitosan adjuvant in an attenuated N. caninum vaccine in BALB/c mice. Twenty-eight BALB/c mice were divided into four groups of seven. Groups 1, 2, and 3 were subcutaneously immunized with attenuated tachyzoites of N. caninum strain Nc-1 combined with micronized chitosan adjuvant at concentrations of 10%, 50%, and 90%, respectively. The fourth group served as the control. All groups were monitored daily over a three-week period. Following sample collection, antibody titters were quantified using ELISA, and cellular immune responses were evaluated by measuring IFN-γ levels with a commercially available assay kit. According to ELISA results, the highest antibody levels were observed in the group immunized with the attenuated N. caninum strain plus 90% chitosan adjuvant, showing a significant difference compared to the control and other groups (P < 0.05). Measurement of IFN-γ revealed that the strongest cellular immune response was observed in the group immunized with 90% chitosan adjuvant, with significant differences compared to the control and other groups (P < 0.05). Based on these findings and the considerable effect of chitosan adjuvant on both antibody titers and cellular immunity, the use of this adjuvant is recommended in the development of Neospora vaccines.

Keywords

Vaccine

Neospora caninum

Adjuvant

Chitosan

Subjects

• Parasitology

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