Immune response of healthy horses to DNA constructs formulated with a cationic lipid transfection reagent

BMC Veterinary Research

J.-M. V. Cavalleri²  K. Feige²  A. Moritz³  P. Jaehnig⁷  B. Wagner⁹  C. Pfarrer⁴  H. Murua Escobar⁶  S. Willenbrock¹  B. Wittig⁵  D. Oswald⁵  C. Juhls⁵  H.-J. Schuberth⁸  M. Koy⁸  P. Steinig²  Christiane L. Schnabel² 

[1] University of Veterinary Medicine Hannover, Small Animal Clinic, Buenteweg 9, Hannover, 30559, Germany;University of Veterinary Medicine Hannover, Clinic for Horses, Buenteweg 9, Hannover, 30559, Germany;Department of Veterinary Medicine, Clinical Sciences, Clinical Pathology and Clinical Pathophysiology, Justus-Liebig-Universitaet, Frankfurter Strasse 126, Giessen, 35392, Germany;University of Veterinary Medicine Hannover, Institute of Anatomy, Bischofsholer Damm 15, Hannover, 30173, Germany;Foundation Institute Molecular Biology and Bioinformatics, Freie Universitaet Berlin, Berlin, Germany;Division of Medicine, Clinic III, Haematology, Oncology and Palliative Medicine, University of Rostock, Rostock, 18057, Germany;pj statistics, Niedstrasse 16, Berlin, 12159, Germany;University of Veterinary Medicine Hannover, Immunology Unit, Bischofsholer Damm 15, Hannover, 30173, Germany;Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell Universit, 240 Farrier Rd, Ithaca 14853, NY, USA

关键词: Cationic lipid;    DNA vaccine;    Transfection reagent;    IL-18;    IL-12;    CpG;    Cytokines;    MIDGE vector;    Grey horse;    Equine melanoma;   

Others  :  1219106
DOI  :  10.1186/s12917-015-0452-3

 received in 2014-12-05, accepted in 2015-06-09,  发布年份 2015

【 摘 要 】

Background

Deoxyribonucleic acid (DNA) vaccines are used for experimental immunotherapy of equine melanoma. The injection of complexed linear DNA encoding interleukin (IL)-12/IL-18 induced partial tumour remission in a clinical study including 27 grey horses. To date, the detailed mechanism of the anti-tumour effect of this treatment is unknown.

Results

In the present study, the clinical and cellular responses of 24 healthy horses were monitored over 72 h after simultaneous intradermal and intramuscular application of equine IL-12/IL-18 DNA (complexed with a transfection reagent) or comparative substances (transfection reagent only, nonsense DNA, nonsense DNA depleted of CG).

Although the strongest effect was observed in horses treated with expressing DNA, horses in all groups treated with DNA showed systemic responses. In these horses treated with DNA, rectal temperatures were elevated after treatment and serum amyloid A increased. Total leukocyte and neutrophil counts increased, while lymphocyte numbers decreased. The secretion of tumour necrosis factor alpha (TNFα) and interferon gamma (IFNγ) from peripheral mononuclear blood cells ex vivo increased after treatments with DNA, while IL-10 secretion decreased. Horses treated with DNA had significantly higher myeloid cell numbers and chemokine (C-X-C motif) ligand (CXCL)-10 expression in skin samples at the intradermal injection sites compared to horses treated with transfection reagent only, suggesting an inflammatory response to DNA treatment.

In horses treated with expressing DNA, however, local CXCL-10 expression was highest and immunohistochemistry revealed more intradermal IL-12-positive cells when compared to the other treatment groups.

In contrast to non-grey horses, grey horses showed fewer effects of DNA treatments on blood lymphocyte counts, TNFα secretion and myeloid cell infiltration in the dermis.

Conclusion

Treatment with complexed linear DNA constructs induced an inflammatory response independent of the coding sequence and of CG motif content. Expressing IL-12/IL-18 DNA locally induces expression of the downstream mediator CXCL-10.

The grey horses included appeared to display an attenuated immune response to DNA treatment, although grey horses bearing melanoma responded to this treatment with moderate tumour remission in a preceding study. Whether the different immunological reactivity compared to other horses may contributes to the melanoma susceptibility of grey horses remains to be elucidated.

【 授权许可】

   
2015 Schnabel et al.

【 图 表 】

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