Cutaneous and serological responses to cat allergen in adults exposed or not to cats

Specific Dog Allergen Immunoglobulin G Antibodies in Patients with Allergic Conjunctivitis

Purpose:

The purpose of the study was to examine the role of total tear IgE, and specific serum dog IgG and IgE antibodies on the severity of allergic conjunctivitis.

Methods:

This study enrolled healthy subjects (control group, N=13), the patients with seasonal allergic conjunctivitis (seasonal group, N=13), and patients with perennial allergic conjunctivitis (perennial group, N=13). Skin prick test, tear IgE level, and serum specific dog IgE and IgG levels were examined. The severity of allergic conjunctivitis using a grading score (0-30) was also examined.

Results:

The levels of serum dog-specific IgE and IgG, and total tear IgE of the seasonal and perennial groups were higher as compared to those of the control group (all p<0.05). The levels of serum dog-specific IgG of the perennial group were higher than those of the seasonal group (0.4 ± 0.6 vs. 0.0 ± 0.0). Multivariate analysis confirmed that the skin prick test result for dog allergen was related to the serum dog-specific IgG levels, but not IgE levels (p<0.01). The severity of allergic conjunctivitis was related to the serum level of dog-specific IgG antibodies (p<0.01).

Conclusion:

It was concluded that dog-specific IgG antibodies level may be associated with the severity of dog-related perennial allergic conjunctivitis.

Specific IgG for cat allergens in patients with allergic conjunctivitis

Immunoglobulin G (IgG) antibodies are involved in type II and type III hypersensitivity. We evaluated the relation between perennial allergic conjunctivitis and serum levels of specific IgG for cat allergens. A prospective study was conducted in patients with seasonal allergic conjunctivitis (seasonal group, n = 10), patients with perennial allergic conjunctivitis (perennial group, n = 10), and healthy control subjects (control group, n = 10). Serum levels of specific IgE and IgG for cat allergens and total tear IgE were measured, and a skin prick test was also performed. In addition, a severity score associated with allergic conjunctivitis was calculated (0-30). The positive rates and scores of for total tear IgE, serum cat-specific IgE, and serum cat-specific IgG were all higher in the seasonal and perennial groups than in the control group (all p < 0.05). Serum cat-specific IgG levels were higher in the perennial group than in the seasonal group (p = 0.0156), but there was no significant difference in the grade of cat-specific IgE between the two groups (p = 0.3008). On multivariate analysis, the mean wheal diameter for cat allergen was associated with the serum level of cat-specific IgG (not IgE) in all patients [odds ratio (OR) = 31.979, p < 0.0001]. Multivariate analysis revealed that the total objective score was strongly associated with serum cat-specific IgG (OR = 23.015, p < 0.0001). These findings suggest that specific IgG antibodies may be involved in perennial allergic symptoms caused by indoor allergens such as cat allergens.

Human allergy to environmental pet danders: a public health perspective

The prevalence of human allergy to pet danders has increased rapidly over the past six decades, as a consequence of lifestyle changes that have enhanced ambient exposure to pet allergens. This is a problem of global public health importance, as the morbidity associated with allergic diseases disproportionately affects socio-economically disadvantaged populations, particularly children. Although the public often seeks advice from veterinary health-care professionals regarding healthy pet ownership practices, including strategies for reducing residential pet dander exposure, many misconceptions persist in the public domain regarding pet dander allergy, such as the belief that certain dog and cat breeds are 'hypoallergenic' due to their hair/coat type. This review considers the epidemiology of human exposure to the major cat and dog dander allergens, Fel d 1 and Can f 1 respectively, and the sensitization mechanisms to them, including the hygiene hypothesis and the putative role of bacterial endotoxin. The literature regarding primary and secondary exposures in different ambient environments is explored including threshold effects that influence allergen sensitization and elicitation of symptoms, and environmental intervention strategies that seek to reduce allergen exposure. Pet-specific factors, including the aetiopathogenesis of the several cat and dog allergens that have been characterized to the molecular level, individual animal characteristics that influence Fel d 1 and Can f 1 shedding, and pet-directed interventions intended to reduce allergen dispersal, are discussed.