A Canine Distemper Model of Virus-Induced Anergy

Abstract

For development of an animal model of virus-induced anergy, the effect of canine distemper virus (CDV) upon cell-mediated immunity in dogs was investigated. First, canine cutaneous reactions and in vitro lymphocyte responses to soluble protein antigens were characterized. Dogs immunized with picryl guinea pig albumin and with keyhole limpet hemocyanin (both in complete Freund's adjuvant) responded reproducibly to intracutaneous challenge with these antigens. Reactivity peaked in 20-40 days (maximal induration, 6-50 mm). Lymphocytes from these animals responded in vitro to stimulation with keyhole limpet hemocyanin or purified protein derivative. This stimulation was antigen-specific and was maximal on day 6 of culture. Infection with CDV depressed cutaneous reactivity and lymphocyte response in vitro to antigens and mitogens. This effect was transient in animals previously vaccinated with attenuated CDV; however, gnotobiotic puppies (susceptible to CDV) had prolonged depression of cell-mediated immunity and lymphopenia. Some of these animals developed neurologic symptoms and died. The findings indicate that CDV infection is a potentially useful model for study of virus-induced depression of T (thymus)-cell responses and support the hypothesis that there is more than one mechanism responsible for this phenomenon.

Suppression of cellular immune responses in guinea pigs infected with spotted fever group rickettsiae

“…Because we used a whole-blood lymphocyte transformation assay, any change in the cellular or serum constituents of the blood could affect our results. Gross cellular changes, such as lymphopenia or leukocytosis, which are believed to cause immunosuppression in other infectious diseases (5,9,10,15), were not observed. However, there may have been functional changes in cellular subpopulations, such as increased suppressor T-lymphocyte activity, which were responsible for the immunosuppression that we observed.…”

Field Evaluation of an Inactivated Vaccine to Control Raccoon Rabies in Ontario, Canada

“…Canine distemper virus is capable of inducing immunosuppression in its host (Kauffman et al, 1982;Williams, 2001) by various mechanisms, which facilitates concurrent infections by other organisms (Mangi et al, 1976). Concurrent infection of raccoons with rabies virus and CDV has been documented in Canada (Rosatte et al, 2007b) and the US.…”

Concurrent Rabies and Canine Distemper Encephalitis in a Raccoon (Procyon Lotor)

“…2,13 The CDV is capable of inducing immunosuppression in its host by various mechanisms, thereby facilitating concurrent infections by other organisms. 11 In raccoons, Tyzzer's disease was reported as a complication of canine distemper, 18 and there have been at least 4 reports of concurrent protozoal encephalitis 3,4,15,17 with canine distemper. A Sarcocystis sp.…”