Lymphocyte blastogenic response to ovalbumin in a model for canine allergy

Lymphocyte stimulation tests (LST) were performed in five dogs sensitised with ovalbumin (OVA) and seven healthy dogs. In addition, all five OVA-sensitised and two control dogs were tested after two in vivo provocations with OVA-containing eye drops. The isolated cells were suspended in culture media containing OVA and were cultured for up to 12 days. Proliferation was measured as reduction in 5,6-carboxylfluorescein diacetate succinimidyl ester (CFSE) intensity by flow cytometry on days 0, 3, 6, 9 and 12. A cell proliferation index (CPI) for each day and the area under the curve (AUC) of the CPI was calculated for each dog. All OVA-sensitised dogs demonstrated increased erythema after conjunctival OVA application. The presence of OVA-specific lymphocytes was demonstrated in 2/5 OVA-sensitised dogs before and 4/5 after in vivo provocation. Using the AUC, the difference between OVA-sensitised and control dogs was significant in all three LST before in vivo provocation (P<0.05) and borderline significant (P=0.053) in 2/3 LST after provocation. The most significant difference in CPI was observed after 9 days of culture (P=0.001). This pilot study indicates that the LST allows detection of rare antigen specific memory T-cells in dogs previously sensitised to, but not concurrently undergoing challenge by a specific antigen.

Important research questions in allergy and related diseases: nonallergic rhinitis: a GA2LEN paper

Nonallergic rhinitis (NAR) can be defined as a chronic nasal inflammation which is not caused by systemic IgE-dependent mechanisms. It is common and probably affects far more than 200 million people worldwide. Both children and adults are affected. However, its exact prevalence is unknown and its phenotypes need to be evaluated using appropriate methods to better understand its pathophysiology, diagnosis and management. It is important to differentiate between infectious rhinitis, allergic/NAR and chronic rhinosinusitis, as management differs for each of these cases. Characterization of the phenotype, mechanisms and management of NAR represents one of the major unmet needs in allergic and nonallergic diseases. Studies on children and adults are required in order to appreciate the prevalence, phenotype, severity and co-morbidities of NAR. These studies should compare allergic and NAR and consider different age group populations including elderly subjects. Mechanistic studies should be carried out to better understand the disease(s) and risk factors and to guide towards an improved diagnosis and therapy. These studies need to take the heterogeneity of NAR into account. It is likely that neuronal mechanisms, T cells, innate immunity and possibly auto-immune responses all play a role in NAR and may also contribute to the symptoms of allergic rhinitis.