The Immune Response toMicrosporum canisInduced by a Fungal Cell Wall Vaccine*

Abstract

An experimental infection model was used to assess induction of specific immunity against Microsporum canis in cats with an M . canis cell wall vaccine preparation. Kittens 8-9 weeks old (n = 12) received five doses of either vaccine or placebo at biweekly intervals. Specific immunity was monitored via plasma anti-dermatophyte antibody titers and lymphocyte blastogenesis (LB) to dermatophyte antigens. After vaccination, cats were chauenged with viable M . canis spores, and lesion development was monitored. Vaccinated cats developed higher anti-dermatophyte IgG, but not IgM, titers than controls, beginning after the second dose of vaccine (P < 0.001). During the vaccination period, specific cellular immunity as measured by LB was absent in control cats, but developed to a limited degree in vaccinated cats (P < 0.05).After challenge with lo5 fungal spores per cat, both control and vaccinated cats developed active infections.The vaccine appeared to induce an antibody titer quantitatively similar to that produced by infection, but less measured cellular immunity than was seen with infection and recovery. These results suggest that induction of high titers of serum IgG or IgM antibody against Microsporum canis is not protective against challenge exposure.

Safety and immunologic effects after inoculation of inactivated and combined live-inactivated dermatophytosis vaccines in cats

“…2,12 Humoral immunity is not considered to be an especially important component of immunity to dermatophytosis, but development of a cell-mediated immune response is paramount. 16 In the study reported here, 2 groups had the mildest infections.…”

Assessment of immunogenicity and protective efficacy of Microsporum canis secreted components coupled to monophosphoryl lipid-A adjuvant in a vaccine study using guinea pigs

“…Several commercial and experimental vaccines against dermatophytosis have been developed and tested. In some cases there were encouraging results Segal, 1994, 1995;Milan et al, 2004;Westhoff et al, 2010) while in other no protective immunity was found (DeBoer and Moriello, 1994Moriello, , 1995DeBoer et al, 2002). The exception is a vaccine for bovine dermatophytosis (Bovilis ® Ringvac Intervet, the Netherlands).…”

Humoral and cellular immune response to a crude exo-antigen and purified keratinase ofMicrosporum canisin experimentally infected guinea pigs

“…Although it is usually confined to the dead keratinized structures, the infection induces a specific humoral and cellular response [2 -7]. Cellular immune response seems to be associated with clinical recovery [5] and protection against reinfection [8,9]. The role of the humoral response remains unclear.…”