Staphylococcus aureus Protection-Related Type 3 Cell-Mediated Immune Response Elicited by Recombinant Proteins and GM-CSF DNA Vaccine.

Kamila R Santos,Eduardo M Ramos-Sanchez,Luiza C Reis,Camila F Batista,Magnus Gidlund,Hiro Goto,Marcos B Heinemann,Andrey P Lage,Wesley F Fotoran,Adriano F Cunha,Angélica Rosa Faria,Hélida M Andrade,Fernando N Souza,Alice M M P Della Libera,Mônica M O P Cerqueira

doi:10.3390/vaccines9080899

Abstract

Staphylococcus aureus mastitis remains a major challenge for dairy farming. Here, 24 mice were immunized and divided into four groups: G1: control; G2: Granulocyte Macrophage Colony-Stimulating Factor (GM-CSF) DNA vaccine; G3: F0F1 ATP synthase subunit α (SAS), succinyl-diaminopimelate (SDD), and cysteinyl-tRNA synthetase (CTS) recombinant proteins; and G4: SAS+SDD+CTS plus GM-CSF DNA vaccine. The lymphocyte subpopulations, and the intracellular interleukin-17A (IL-17A) and interferon-γ production in the draining lymph node cells were immunophenotyped by flow cytometry. The immunophenotyping and lymphocyte proliferation was determined in spleen cells cultured with and without S. aureus stimulus. Immunization with S. aureus recombinant proteins generated memory cells in draining lymph nodes. Immunization with the three recombinant proteins plus GM-CSF DNA led to an increase in the percentage of IL-17A+ cells among overall CD44+ (memory), T CD4+, CD4+ T CD44+ CD27−, γδ TCR, γδ TCR+ CD44+ CD27+, and TCRVγ4+ cells. Vaccination with S. aureus recombinant proteins associated with GM-CSF DNA vaccine downregulated TH2 immunity. Immunization with the three recombinant proteins plus the GM-CSF DNA led to a proliferation of overall memory T, CD4+, and CD4+ TEM cells upon S. aureus stimulus. This approach fostered type 3 immunity, suggesting the development of a protective immune response against S. aureus.

Highlights

Bovine mastitis is the disease with the greatest global impact on dairy farming, causing a pronounced reduction in milk production and quality
Aiming for an effective vaccine for S. aureus bovine intramammary infections (IMIs), in the present study we propose evaluating the immune response profile triggered by three recombinant S. aureus vaccine candidate antigens (SAS, SDD, and cysteinyl-tRNA synthetase (CTS)) in association with Granulocyte Macrophage Colony-Stimulating Factor (GM-CSF) DNA vaccine in a mouse model
In the present study, when we compared the percentage of proliferative cells between S. aureus stimulated and unstimulated conditions within groups, we observed that animals that received the S. aureus recombinant proteins plus GM-CSF DNA vaccine showed an increase in the percentage of proliferative overall memory T cells (CD44+; p = 0.02), CD4+ cells (p = 0.02) and CD4+ TEM (CD44+ CD27−; p = 0.01) when stimulated with S. aureus, which was not sustained in other experimental groups as shown in Supplementary Figure S3

Summary

Introduction

Bovine mastitis is the disease with the greatest global impact on dairy farming, causing a pronounced reduction in milk production and quality. Several etiologic agents are implied in mastitis, but Staphylococcus aureus is considered one of the most prevalent mastitis pathogens. We intended to take advantage of the knowledge derived from detailed analysis and characterization of the immune response that favored the host to identify promising epitopes for immunization [1,2,5,6]. Using this approach, we previously searched S. aureus-derived proteins likely related to protection [2]. Based on these antigenic proteins revealed by a serum immunoproteomics approach, we obtained three candidate proteins: F0F1 ATP synthase subunit α (SAS), succinyl-diaminopimelate (SDD), and cysteinyl-tRNA synthetase (CTS) [2]

Methods

Findings

Discussion

Conclusion