Nanoparticle-Based Delivery of Anaplasma marginale Membrane Proteins; VirB9-1 and VirB10 Produced in the Pichia pastoris Expression System.
Bovine anaplasmosis or cattle-tick fever is a tick-borne haemolytic disease caused by the rickettsial haemoparasiteAnaplasma marginalein tropical and subtropical areas of the world. While difficult to express, the proteins VirB9-1 and VirB10 are immunogenic components of the outer membrane type IV secretion system that have been identified as candidate antigens for vaccines targeting ofA. marginale. Soluble VirB9-1 and VirB10 were successfully expressed usingPichia pastoris. When formulated with the self-adjuvanting silica vesicles, SV-100 (diameter: 50 nm, and pore entrance size: 6 nm), 200 µg of VirB9-1 and VirB10 were adsorbed per milligram of nanoparticle. The VirB9-1 and VirB10, SV-100 formulations were shown to induce higher antibody responses in mice compared to the QuilA formulations. Moreover, intracellular staining of selected cytokines demonstrated that both VirB9-1 and VirB10 formulations induced cell-mediated immune responses in mice. Importantly, the SV-100 VirB9-1 and VirB10 complexes were shown to specifically stimulate bovine T-cell linages derived from calves immunised withA. marginaleouter membrane fractions, suggesting formulations will be useful for bovine immunisation and protection studies. Overall this study demonstrates the potential of self-adjuvanting silica vesicle formulations to address current deficiencies in vaccine delivery applications.
Department of Agriculture and Fisheries, Agri-Science Queensland, Animal Science, St Lucia, QLD 4072, Australia. bing.zhang@daf.qld.gov.au.
Bing
B
Zhang
Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072, Australia. a.cavallaro@uq.edu.au.
Antonio S
AS
Cavallaro
Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072, Australia. k.mody@uq.edu.au.
Karishma T
KT
Mody
Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia. jun.zhang1@uqconnect.edu.au.
Jun
J
Zhang
Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA. jderinger@vetmed.wsu.edu.
James R
JR
Deringer
Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164, USA. wbrown@vetmed.wsu.edu.
Wendy C
WC
Brown
Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072, Australia. t.mahony@uq.edu.au.
Timothy J
TJ
Mahony
Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD 4072, Australia. c.yu@uq.edu.au.
Chengzhong
C
Yu
Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD 4072, Australia. n.mitter@uq.edu.au.
Neena
N
Mitter
Anaplasma marginale; Pichia pastoris; VirB10; VirB9-1; immune responses; silica vesicles; vaccine adjuvants