Food-specific sublingual immunotherapy is well tolerated and safe in healthy dogs: a blind, randomized, placebo-controlled study

Abstract

BackgroundFood allergies are increasing in prevalence but no treatment strategies are currently available to cure dogs with food allergy. Over the past decade, experimental food allergen-specific sublingual immunotherapy (FA-SLIT) has emerged as a potential treatment for food allergies in human medicine. However, FA-SLIT has not been investigated in dogs. Therefore, the objective of this study was to prospectively evaluate the safety, tolerability and dispenser sterility of FA-SLIT in healthy dogs before testing it in food allergic dogs.Eight experimental healthy beagle dogs, never orally exposed to peanut, were randomized in two groups to receive SLIT with peanut or placebo for 4 months. Subjects were monitored daily for local and systemic adverse effects. Blood samples for complete blood count and serum biochemistry, and urine for urinalysis were collected and the dogs’ body weight was recorded at day 0, 35 and 119 of the SLIT treatment. Sera for the determination of peanut-specific IgG and IgE were collected at day 0, 35, 49, 70, 91, 105 and 119. Intradermal tests were performed before (day 0) and after (day 119) the experiment. The content of each dispenser used to administer treatment or placebo was tested for sterility after usage. In order to assess the presence or absence of sensitization, dogs were challenged 6 months after the end of the study with 2000 μg of peanut extract daily for 7 to 14 days.ResultsAll dogs completed the study. The treatment did not provoke either local or systemic side-effects. Peanut-specific IgG significantly increased in treatment group. Even though a significant increase in peanut-specific IgE was also seen, intradermal tests were negative in all dogs before and after the experiment, and the challenge test did not trigger any adverse reactions in the treated dogs, which shows the protocol did not cause sensitization to peanut, but nevertheless primed the immune system as indicated by the humoral immune response. All dispenser solutions were sterile.ConclusionsOur results demonstrate that the used peanut-SLIT protocol is well tolerated and safe in healthy dogs. Further studies should evaluate tolerability, safety and efficacy in dogs with food allergy.

Outstanding animal studies in allergy I. From asthma to food allergy and anaphylaxis

“…Although in these animals little is known about the eliciting specific allergen molecules [ 8 , 9 ], the immune mechanisms relevant for allergies in dog, cat and horses are more similar to humans than any rodent models. These facts prompted experimental approaches including models for food sensitization [ 10 ] or for sublingual allergen-specific immunotherapy [ 11 ], up to clinical comparative investigations in animal patients, which are very similar to humans [ 12 , 13 ]. Technically, however, all investigations in animals are regulated by the animal experimentation directives [ 14 ].…”

Combined IMIG and Immune Ig Attenuate Allergic Responses in Beagle Dogs

“…Testing this hypothesis initially in a mouse model using BALB/c mice sensitized with ovalbumin showed that attenuation of allergic responses was seen in mice receiving commercial immune Ig and anti-idiotype Ig of human origin, see Figures 3 and 4. These important observations justified a pilot preclinical trial of this same therapy in a dog model (Beagles) of atopic dermatitis, the most common allergic skin disease in dogs [5][6][7][8][9][10].…”

“…Skin, respiratory, and food allergies are not uncommon in dogs, and the immune mechanisms involved are more like humans than in rodents [5,6], making them a favoured species for study [7][8][9][10][11]. Dust mite allergens are thought to be highly relevant to canine allergic responses [12], although skin reactivity and dust mite-specific serum IgE have also been detected in several dogs without clinical signs of allergy, suggesting that sensitization can occur without necessarily inducing clinically significant reactivity [13].…”