Proteome Modulation in Peripheral Blood Mononuclear Cells of Peste des Petits Ruminants Vaccinated Goats and Sheep

Abstract

In the present study, healthy goats and sheep (n = 5) that were confirmed negative for peste des petits ruminants virus (PPRV) antibodies by monoclonal antibody-based competitive ELISA and by serum neutralization test and for PPRV antigen by s-ELISA were vaccinated with Sungri/96. A quantitative study was carried out to compare the proteome of peripheral blood mononuclear cells (PBMCs) of vaccinated goat and sheep [5 days post-vaccination (dpv) and 14 dpv] vs. unvaccinated (0 day) to divulge the alteration in protein expression following vaccination. A total of 232 and 915 proteins were differentially expressed at 5 and 14 dpv, respectively, in goats. Similarly, 167 and 207 proteins were differentially expressed at 5 and 14 dpv, respectively, in sheep. Network generated by Ingenuity Pathway Analysis was "infectious diseases, antimicrobial response, and inflammatory response," which includes the highest number of focus molecules. The bio functions, cell-mediated immune response, and humoral immune response were highly enriched in goats at 5 dpv and at 14 dpv. At the molecular level, the immune response produced by the PPRV vaccine virus in goats is effectively coordinated and stronger than that in sheep, though the vaccine provides protection from virulent virus challenge in both. The altered expression of certain PBMC proteins especially ISG15 and IRF7 induces marked changes in cellular signaling pathways to coordinate host immune responses.

Keywords: PPRV; Sungri/96; immunity; proteome; vaccine.

Figure 1

(A) Differentially expressed proteins (DEPs) in vaccinated goats and sheep at 5 days post-vaccination (dpv) and 14 dpv. (B) DEPs in vaccinated goats and sheep at 5 and 14 dpv with cutoff fold change >2 for upregulated and <0.5 for downregulated proteins. (C) Venn diagram representing common and unique DEPs between sheep and goats at 5 and 14 dpv.

Figure 2

Protein set enrichment analysis using the ClueGO at (A) 5 days post-vaccination (dpv) and (B) 14 dpv vaccinated goats and (C) 5 dpv and (D) 14 dpv vaccinated sheep. The edges of the resulting ClueGO network are based on kappa statistics and reflect the relationships between the GO terms (network nodes) based on the similarity of their associated proteins. The proteins associated with significant GO categories are displayed as well as the p-value associated with the GO term. In the network, only significantly enriched categories (p-value 0.05, Bonferroni corrected) are shown. The size of the node indicates significance, and the color indicates a group.

Figure 3

Canonical pathways activated/inactivated in vaccinated goats (A) 5 days post-vaccination (dpv) and (B) 14 dpv were generated in core analysis of the Ingenuity Pathway Analysis (IPA) tool. Red pathways are activated (>2), and blue pathways are inactivated (<2). Height of the bar graphs indicates -log (p-value), and the line graph shows the ratio of listed proteins found in each pathway over the total number of proteins in that pathway. The uniport ID of differentially expressed proteins (DEPs) was converted into gene ID, and this list of proteins with corresponding fold change was uploaded in IPA for downstream analysis.

Figure 4

Canonical pathways activated/inactivated in vaccinated sheep (A) 5 days post-vaccination (dpv) and (B) 14 dpv were generated in core analysis of the Ingenuity Pathway Analysis (IPA) tool. Red pathways are activated (>2), and blue pathways are inactivated (<2). Height of the bar graphs indicates -log (p-value), and the line graph shows the ratio of listed proteins found in each pathway over the total number of proteins in that pathway. The uniport ID of differentially expressed proteins (DEPs) was converted into gene ID, and this list of proteins with corresponding fold change was uploaded in IPA for downstream analysis.

Figure 5

Network generated in Ingenuity Pathway Analysis tool of “infectious diseases, antimicrobial response, and inflammatory response” of differentially expressed proteins (DEPs) in vaccinated goats at (A) 5 days post-vaccination (dpv) and (B) 14 dpv. Proteins that were upregulated are shown in red, and those that were downregulated are shown in green. Proteins in white were not significantly dysregulated. Symbol shape indicates gene function.

Figure 6

Network generated in Ingenuity Pathway Analysis tool of “infectious diseases, antimicrobial response, and inflammatory response” of differentially expressed proteins (DEPs) in vaccinated sheep at (A) 5 days post-vaccination (dpv) and (B) 14 dpv. Proteins that were upregulated are shown in red, and those that were downregulated are shown in green. Proteins in white were not significantly dysregulated. Symbol shape indicates gene function.

Figure 7

Comparison analysis of canonical pathways significantly enriched in vaccinated goats and sheep at (A) 5 days post-vaccination (dpv) and (B) 14 dpv generated in the Ingenuity Pathway Analysis tool.

Figure 8

Comparison of significant enrichment (–log p-value) of proteins in cell-mediated immune response and humoral immune response bio functions between vaccinated sheep and goats at (A) 5 days post-vaccination (dpv) and (B) 14 dpv.