A ferret model of immunosuppression induced with dexamethasone.

Ferrets are nowadays frequently used as animal models for biomedical purposes; in many cases, immunosuppression of experimental animals is necessary. The aim of this study was to evaluate the effect of intramuscular dexamethasone administration (2 mg/kg as the initiation dose continued with 1 mg/kg q 12 h applied 5 times) on ferret's immune system. In comparison with ferrets which received the saline (n = 5), significantly lower total counts of leukocytes (P < 0.01), lymphocytes (P < 0.01) and monocyte (P < 0.05), as well as absolute numbers of CD4+CD8- (P < 0.01) and CD4-CD8+ (P < 0.01) subsets were noted in dexamethasone treated ferrets (n = 5) the first day after the treatment (D1). Absolute number of CD79+ lymphocytes remained unchanged throughout the experiment. The proliferation activity of lymphocytes in dexamethasone treated ferrets was lower only in D1 using concanavalin A (conA), phytohemagglutinin (PHA) and pokeweed mitogen (PWM); statistical significance was noted using PHA 40 (P < 0.05) and PWM 10 (P < 0.01). Lower neutrophil activity (P < 0.01) was detected in D1 after the dexamethasone treatment in both production of reactive oxygen species (chemiluminescence test) and ingestion of particles (phagocytosis assay). The dexamethasone treatment proved to be useful for short-term immunosuppression in ferrets. The results closely resembled data previously reported in human studies and indicate classification of ferrets as steroid-resistant species.

The immune system of the ferret (Mustela putorius furo) - A review.

The basic information dealing with the anatomy of the ferret's immune system, cross-reactivity of the ferret leukocytes with polyclonal and monoclonal antibodies in vitro and immune response to the mitogens and various infections are presented. The leukocyte numbers in the peripheral blood in the ferrets are lower compared to other species and only one subclass of IgG has been identified in ferrets so far. Lymphocytes make up 12-67% of all the leukocytes in the peripheral blood of the healthy adult ferrets. Lymphocyte subpopulations are similar to other mammals and include T- and B-lymphocytes. T-lymphocytes differentiate into helper (Th) lymphocytes and cytotoxic (Tc) lymphocytes. Currently, ferret granulocytes (CD11), B-lymphocytes (CD79α), T-lymphocytes (CD3), Th-lymphocytes (CD3, CD4), Tc-lymphocytes (CD3, CD8), and CD30, CD45 subpopulations are detected with the use of a number of polyclonal as well as with monoclonal antibodies. In a lymphocyte transformation assay, the mitogen response of the peripheral blood mononuclear cells to concanavalin A (ConA), phytohaemagglutinin (PHA), and pokeweed mitogen (PWM) is the greatest at day 2, 2 and 3, respectively. Serious lymphopenia is observed in ferrets during a distemper infection. A significant decrease in the lymphocyte transformation activity is observed on day 5 and reaches a maximal decrease on days 8-11, with full recovery on days 23-30 after the inoculation of laboratory ferrets with the distemper virus. Ferrets have also been used in studies related to the function of the immune system in Helicobacter pylori infections, Crohn's disease and bronchial asthma.