Identification of suitable adjuvant for vaccine formulation with the Neospora caninum antigen NcSRS2

Abstract

The parasite Neospora caninum is the main cause of abortion in cattle in many countries around the world, so a vaccine is a rational approach method for the control of the disease. An effective vaccine should be able to prevent both, the horizontal and vertical transmission of N. caninum. In this study, the immune vaccinal response of the recombinant protein rNcSRS2 of N. caninum expressed in Pichia pastoris and formulated with water-in-oil emulsion, xanthan gum, and alum hydroxide was assessed in an experimental murine model. Groups of 10 Balb/c mice were subcutaneously inoculated with two doses of prNcSRS2 twenty-one days apart. After the second immunization, four mice from each group were euthanized, and splenocytes were stimulated ex vivo with recombinant protein. The IgG dynamics were evaluated by indirect ELISA, and the splenocytes cytokines transcription by qPCR. All groups elicited specific antibodies against prNcSRS2, with the water-in-oil group showing significantly (p .05) elevated titers compared to the other groups. The prNcSRS2 protein alone did not induce a significant ex vivo splenic transcription level of IFN-c, TNF-a, IL-4, IL-10, and IL-12 cytokines, except for IL-17A, and the adjuvant associations with the prNcSRS2 protein induced different cytokine transcription profiles. The water-inoil emulsion modulated the expression of TNF-a; the xanthan gum modulated IL-4, IL-10, and IL-12; and alum hydroxide modulated IFN-c, TNF-a, IL-4, IL-10, and IL-12. In conclusion, it was found that the association of the recombinant prNcSRS2 protein with different adjuvants induced different levels of specific antibody, and a distinct splenic cytokine profile in an adjuvant-dependent manner. The mechanisms of adjuvancity activity is complex, so adjuvant formulation may help in the design of efficient vaccine to control Neosporosis.

Recombinant BoHV-5 Glycoprotein Elicits Long-Lasting Protective Immunity in Cattle

“…However, in our previous study, we do not observe upregulation of the IL4 in female outbred Swiss albino mice splenocytes stimulated for 18 h with 10 μg of rgD5 [10]. Nevertheless, a similar effect toward a Th1 response using an oil-based adjuvant was reported [48,49], when a TLR ligand agonist was used. Except for TLR-9, significant upregulation of all TLRs has been detected following primary infection of neural tissues by both BoHV-1 and -5 herpesviruses, but the role of gD in this mechanism is not totally known [50].…”

Immunocontraceptive potential of a recombinant chimeric protein composed by a single gonadotropin-releasing hormone molecule and B subunit of Escherichia coli heat-labile enterotoxin in a mice model

“…Our group, studying the immune response of a recombinant glycoprotein gD (rgD5) of Bovine Herpes virus (BoHV-5) adjuvanted with Montanide ISA50V2, in a mice model, showed similar results, where higher antibodies titers were obtained at day 28 th and maintaining these high levels up to the end of the experiment (Dummer et al, 2014). Pinheiro et al (2018), studying the role of different adjuvants in the immune response to a Neospora caninum recombinant protein (rNCSRS2), reported very similar results, with a significant vaccinal response after the boost, and an IgG1/IgG2 profile similar to this study, corroborating with a Indicate the groups that showed statistically significant differences (P < 0.05) when compared with the control group.…”

Protective Immunity Against Neospora Caninum Infection Induced by 14-3-3 Protein in Mice

“…Pregnant mice immunized with T. gondii GRA17 or GRA24 produced high levels of IL-10, which could modulate the pathological damage in foetal mice induced by a large amount of the Th1 cytokine IFN-γ induced by T. gondii challenge [31,39]. BALB/c mouse vaccination with the recombinant protein rNcSRS2 of N. caninum promoted the upregulation of IL-10 expression [40]. Another study also reported a role for B cells in cytokine production in mouse spleen cells, especially IFN-γ and IL-10, in mice restimulated with Neospora antigens.…”