Clinical and cytokine responses to house dust mite sublingual immunotherapy.

BACKGROUND: Cytokine responses accompanying sublingual immunotherapy (SLIT) responder phenotypes have not previously been reported. OBJECTIVE: To investigate clinical and cytokine responses of house dust mite (HDM) sensitive patients with allergic rhinitis receiving HDM SLIT or placebo for 2 years. METHODS: Sixty adults were randomized to receive SLIT or placebo. Clinical symptoms were measured using the Total 5 Symptom Score (TSS5) and Juniper Rhinitis Quality of Life Questionnaire. HDM specific IgE, IgG, skin prick tests, and HDM-stimulated release of interleukin (IL) 5 and interferon γ (IFN-γ) in peripheral blood mononuclear cells was studied at 0, 6, 12, and 24 months and IL-13, IL-4, and IL-10 at 0 and 24 months. RESULTS: A total of 32 of 39 SLIT and 16 of 21 placebo patients completed the study. There was significant clinical improvement in both the SLIT and placebo groups. Median T5SS decreased from 14.75 to 5.25 in the SLIT group (P < .001) and 12.7 to 6.0 in the placebo group (P = .003). The median quality-of-life score also decreased in the SLIT group (P < .001) and the placebo group (P < .001). A subgroup analysis of patients found a 60% or greater improvement (on the T5SS and the Juniper Rhinitis Quality of Life Questionnaire) in the good responders group and a 30% to 59% improvement or no improvement in the intermediate responders group. This subgroup analysis also found more good responders in the SLIT group (47%) compared with the placebo group (25%; P = .07). Significant decreases in the IL-5/IFN-γ (P < .001), IL-13/IFN-γ (P < .001), and IL-4/IFN-γ (P = .03) ratios were found in the combined good clinical improvement group at 24 months. CONCLUSION: A good clinical response (≥60% improvement in both TSS5 and quality of life) is associated with significant decreases in IL-5, IL-13, and IL-4 relative to IFN-γ during 2 years of SLIT therapy for HDMs.

Food allergy in South African children with atopic dermatitis.

BACKGROUND: The prevalence of food allergy in South Africa is unknown, but previously thought to be rare in black South Africans. This study aimed to determine the prevalence of, and risk factors for, IgE-mediated food allergy in South African children with atopic dermatitis (AD). METHODOLOGY: This was a prospective, observational study in a paediatric university hospital in Cape Town. Children with AD, aged 6 months to 10 yrs, were randomly recruited from the dermatology clinic. They were assessed for sensitization and allergy by questionnaire, skin prick tests, Immuno Solid Phase Allergen Chip (ISAC) test and incremental food challenges. RESULTS: 100 participants (59 black Africans and 41 of mixed race) were enrolled, median age 42 months. There were high overall rates of food sensitization (66%) and food allergy (40%). Egg (25%) and peanut (24%) were the most common allergies. Black participants had comparable sensitization (69% vs. 61%) but lower allergy rates (34% vs. 46%) than mixed race participants. This was especially evident for peanut allergy (15% Blacks vs. 37% mixed race allergic to peanut, p = 0.01). Early-onset AD (<6 months), severe eczema, and young age <2 yrs were significant risk factors for food allergy. CONCLUSION: The prevalence of food allergy is unexpectedly high in South African children with AD, and comparable with food allergy rates in patients with AD in developed countries. There are ethnic differences, with significantly lower peanut allergy rates in Blacks compared to mixed race patients. These results are not generalizable to an unselected South African population, which requires further study.

Development of a monoclonal antibody detection assay for species-specific identification of abalone.

Species identification based on biochemical and molecular techniques has a broad range of applications. These include compliance enforcement, the management and conservation of marine organisms, and commercial quality control. Abalone poaching worldwide and illegal trade in abalone products have increased mainly because of the attractive prices obtained and caused a sharp decline in stocks. Alleged poachers have been acquitted because of lack of evidence to correctly identify species. Therefore, a robust method is required that would identify tissue of abalone origin to species level. The aim of this study was to develop immunologic techniques, using monoclonal and polyclonal antibodies, to identify 10 different abalone species and subspecies from South Africa, the United States, Australia, and Japan. The combination of 3 developed monoclonal antibodies to South African abalone (Haliotis midae) enabled differentiation between most of the 10 species including the subspecies H. diversicolor supertexta and H. diversicolor diversicolor. In a novel approach, using antibodies of patients with allergy to abalone, the differentiation of additional subspecies, H. discus discus and H. discus hannai, was possible. A field-based immunoassay was developed to identify confiscated tissue of abalone origin.