title: In Vitro Influence of Mycophenolic Acid on Selected Parameters of Stimulated Peripheral Canine Lymphocytes.
abstract: Mycophenolic acid (MPA) is an active metabolite of mycophenolate mofetil, a new immunosuppressive drug effective in the treatment of canine autoimmune diseases. The impact of MPA on immunity is ambiguous and its influence on the canine immune system is unknown. The aim of the study was to determine markers of changes in stimulated peripheral canine lymphocytes after treatment with MPA in vitro. Twenty nine healthy dogs were studied. Phenotypic and functional analysis of lymphocytes was performed on peripheral blood mononuclear cells cultured with mitogens and different MPA concentrations- 1 μM (10(-3) mol/m(3)), 10 μM or 100 μM. Apoptotic cells were detected by Annexin V and 7-aminoactinomycin D (7-AAD). The expression of antigens (CD3, CD4, CD8, CD21, CD25, forkhead box P3 [FoxP3] and proliferating cell nuclear antigen [PCNA]) was assessed with monoclonal antibodies. The proliferation indices were analyzed in carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled cells. All analyses were performed using flow cytometry. The influence of MPA on apoptosis was dependent on the mechanism of cell activation and MPA concentration. MPA caused a decrease in the expression of lymphocyte surface antigens, CD3, CD8 and CD25. Its impact on the expression of CD4 and CD21 was negligible. Its negative influence on the expression of FoxP3 was dependent on cell stimulation. MPA inhibited lymphocyte proliferation. In conclusion, MPA inhibited the activity of stimulated canine lymphocytes by blocking lymphocyte activation and proliferation. The influence of MPA on the development of immune tolerance-expansion of Treg cells and lymphocyte apoptosis-was ambiguous and was dependent on the mechanism of cellular activation. The concentration that MPA reaches in the blood may lead to inhibition of the functions of the canine immune system. The applied panel of markers can be used for evaluation of the effects of immunosuppressive compounds in the dog.
authors.affiliation: Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.|Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Maciej
authors.initials: M
authors.lastname: Guzera
authors.affiliation: Department of Preclinical Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors.forename: Lidia
authors.initials: L
authors.lastname: Szulc-Dąbrowska
authors.affiliation: Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Cywińska
authors.affiliation: Department of Veterinary Medicine, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Joy
authors.initials: J
authors.lastname: Archer
authors.affiliation: Department of Pathology and Veterinary Diagnostics, Faculty of Veterinary Medicine, Warsaw University of Life Sciences, Warsaw, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Winnicka
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004285:Dogs; D051858:Forkhead Transcription Factors / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism; D009173:Mycophenolic Acid / Q000494:pharmacology*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D051858:Forkhead Transcription Factors; D018809:Proliferating Cell Nuclear Antigen; D009173:Mycophenolic Acid