Evaluation of a Recombinant Mouse X Pig Chimeric Anti-Porcine DEC205 Antibody Fused with Structural and Nonstructural Peptides of PRRS Virus

Abstract

Activation of the immune system using antigen targeting to the dendritic cell receptor DEC205 presents great potential in the field of vaccination. The objective of this work was to evaluate the immunogenicity and protectiveness of a recombinant mouse x pig chimeric antibody fused with peptides of structural and nonstructural proteins of porcine respiratory and reproductive syndrome virus (PRRSV) directed to DEC205+ cells. Priming and booster immunizations were performed three weeks apart and administered intradermally in the neck area. All pigs were challenged with PRRSV two weeks after the booster immunization. Immunogenicity was evaluated by assessing the presence of antibodies anti-PRRSV, the response of IFN-γ-producing CD4+ cells, and the proliferation of cells. Protection was determined by assessing the viral load in the blood, lungs, and tonsils using qRT-PCR. The results showed that the vaccine exhibited immunogenicity but conferred limited protection. The vaccine group had a lower viral load in the tonsils and a significantly higher production of antibodies anti-PRRSV than the control group (p < 0.05); the vaccine group also produced more CD4+IFN-γ+ cells in response to peptides from the M and Nsp2 proteins. In conclusion, this antigenized recombinant mouse x pig chimeric antibody had immunogenic properties that could be enhanced to improve the level of protection and vaccine efficiency.

Swine Dendritic Cell Response to Porcine Reproductive and Respiratory Syndrome Virus: An Update

“…With a similar approach but using selected peptides from structural and non-structural proteins of PRRSV, Bustamante-Córdova et al. ( 78 ) obtained similar results. More studies are needed to identify if this strategy is suitable for PRRSV in combination with the identification of more immunogenic antigens, better immunization routes, and adjuvant combinations.…”

Skin-Based Vaccination: A Systematic Mapping Review of the Types of Vaccines and Methods Used and Immunity and Protection Elicited in Pigs

“…In a few studies, minipigs were used as they are regarded as a suitable model when it comes to vaccination through the skin [ 83 ]. It is noted that almost half of the identified papers (n = 57), do not name the pig breed, often referring to it only as commercial breed [ 49 , 51 , 76 , 108 , 109 , 110 , 111 , 112 , 113 , 114 , 115 , 116 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142 , 143 , 144 , 145 , 146 , 147 , 148 , 149 , 150 , 151 , 152 , 153 ,…”

“…Adjuvants are used to enhance and modulate vaccine-induced immunity. Over 60% of identified papers using skin-based vaccination in pigs included adjuvants; the majority mixed or co-inoculated with the vaccine [ 51 , 76 , 88 , 108 , 110 , 112 , 113 , 115 , 117 , 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 129 , 131 , 132 , 133 , 134 , 137 , 138 , 139 , 140 , 141 , 142 , 143 , 144 , 146 , 151 , 153 , 154 , 156 , 158 , 159 , 160 , 161 , 168 , 179 , 180 , 182 , 186 , 187 , 188 , 196 , 198 , 199 , 201 , 202 ,…”

“…Compared with placebo, strong humoral responses induced by skin-based immunisation led to better protection after homologous, heterologous virus strain challenge or natural infection, shown as a decrease in clinical signs, lung lesions, viral shedding or viremia [ 76 , 112 , 134 , 135 , 139 , 157 , 220 ]. However, increased antibodies do not always correlate with protection, as observed by partial, limited or no efficacy of a subunit [ 123 ] or an inactivated vaccine [ 227 ] after challenge despite an increase in specific-antibodies. Furthermore, some PRRSV vaccines, such as an adjuvanted inactivated vaccine delivered into the skin, did not induce seroconversion even after challenge, and no protection was observed [ 228 ].…”

Antigen Targeting of Porcine Skin DEC205+ Dendritic Cells

“…Previously, our research group developed a recombinant mouse × pig chimeric antibody against porcine DEC205 receptor (rAb ZH9F7), and antigens from PRRSV were targeted by intradermal application [ 16 , 17 ]. The obtained results showed that the system was immunogenic with limited protective immunity.…”