Chiung-Hui Huang

Airway Inflammation and IgE Production Induced by Dust Mite Allergen-Specific Memory/Effector Th2 Cell Line Can Be Effectively Attenuated by IL-35

CD4+ memory/effector T cells play a central role in orchestrating the rapid and robust immune responses upon re-encounter with specific Ags. However, the immunologic mechanism(s) underlying these responses are still not fully understood. To investigate this, we generated an allergen (major house dust mite allergen, Blo t 5)-specific murine Th2 cell line that secreted IL-4, IL-5, IL-10, and IL-13, but not IL-9 or TNF-α, upon activation by the cognate Ag. These cells also exhibited CD44highCD62L− and CD127+ (IL-7Rα+) phenotypes, which are characteristics of memory/effector T cells. Experiments involving adoptive transfer of this Th2 cell line in mice, followed by three intranasal challenges with Blo t 5, induced a dexamethasone-sensitive eosinophilic airway inflammation. This was accompanied by elevation of Th2 cytokines and CC- and CXC-motif chemokines, as well as recruitment of lymphocytes and polymorphic mononuclear cells into the lungs. Moreover, Blo t 5-specific IgE was detected 4 d after the last intranasal challenge, whereas elevation of Blo t 5-specific IgG1 was found at week two. Finally, pulmonary delivery of the pVAX–IL-35 DNA construct effectively downregulated Blo t 5-specific allergic airway inflammation, and i.m. injection of pVAX–IL-35 led to long-lasting suppression of circulating Blo t 5-specific and total IgE. This model provides a robust research tool to elucidate the immunopathogenic role of memory/effector Th2 cells in allergic airway inflammation. Our results suggested that IL-35 could be a potential therapeutic target for allergic asthma through its attenuating effects on allergen-specific CD4+ memory/effector Th2 cell-mediated airway inflammation.

Characterization of glutathione S‐transferase from dust mite, Der p 8 and its immunoglobulin E cross‐reactivity with cockroach glutathione S‐transferase

Background Sensitization to mite and cockroach allergens is common, and diagnosis and therapy of allergy can be further complicated by the presence of allergen isoforms and panallergens. Purified recombinant and native allergens are useful for studies to resolve such problems.

The Blomia tropicalis Allergens

Blomia tropicalis allergens are the most important mite allergens in tropical regions. Most of them only have 30-40% sequence identity with their Dermatophagoides counterparts and they share low IgE cross reactivity and exhibit different immunobiology. Unlike the pyroglyphid counterparts, Blo t 5 is the major allergen whereas Blo t 1 only has modest allergenicity.

DNA vaccines for the prevention and treatment of allergy.

Purpose of reviewAntiallergy DNA vaccine is an attractive alternative for the prevention and treatment of allergic diseases. This review covers recent studies to enhance potency and safety of antiallergy DNA vaccines. Recent findingsDendritic cell-targeted allergen gene vaccination using fascin gene promoter inhibited IgE production and allergic inflammation but not airway hyperresponsiveness. Targeting allergen expression at immature dendritic cells or induction of tolerogenic dendritic cells could induce antiallergic T regulatory cells. Vaccination with DNA-encoded Ag85B and AIMP1 as adjuvants could downregulate established Th2-mediated allergic responses. Forced ubiquitation or targeting allergens to lysosomal/endosomal compartments could avoid risk of allergen sensitization. Gene gun delivery of conventional antiallergy DNA vaccine is a risk factor. Replicase-based allergy DNA vaccines showed enhanced immunogenecity and safety as compared to conventional DNA vaccines. TANK-binding kinase-1 (TBK1) is a novel key molecule in DNA vaccine-induced immunogenicity. SummaryDendritic cell-based approach has been actively explored to enhance immunogenicity of antiallergy DNA vaccines. Codelivery of hypoallergenic DNA vaccines with potent adjuvants via a desirable delivery mode will help to fulfill the requirements for clinical application of antiallergy DNA vaccines. Activation of TBK1 signaling pathway could be a novel strategy to enhance immunogenicity of DNA vaccines.

Cornulin, a marker of late epidermal differentiation, is down-regulated in eczema.

Background:  Eczema is a common chronic inflammatory skin disorder which shows strong genetic predisposition. To identify new potential molecular determinants of the disease pathogenesis, we performed a gene expression study in an eczema mouse model. This analysis identified a marked down regulation of the cornulin gene (CRNN), a member of the epidermal differentiation complex, in the eczema‐like skin. We then investigated CRNN as an eczema candidate gene and studied its polymorphism and the expression in the skin of eczema patients.

Generation of monoclonal antibodies against Blo t 3 using DNA immunization with in vivo electroporation

Background House dust mite allergy is closely associated with allergic diseases. Blomia tropicalis mite species is an important clinical species in the tropics. The cDNA clone encoding Blo t 3, a group 3 allergen from B. tropicalis, has been isolated in our laboratory.

Characterization of an immunomodulatory Der p 2-FIP-fve fusion protein produced in transformed rice suspension cell culture

Der p 2, a major allergen of Dermatophagoides pteronyssinus mites, is one of the most clinically relevant allergens to allergic patients worldwide. FIP-fve protein (Fve) from the golden needle mushroom (Flammulina velutipes) is an immunomodulatory protein with potential Th1-skewed adjuvant properties. Here, we produced and immunologically evaluated a Der p 2-Fve fusion protein as a potential immunotherapeutic for allergic diseases. Using an inducible expression system in cultured rice suspension cells, the recombinant Der p 2-Fve fusion protein (designated as OsDp2Fve) was expressed in rice cells under the control of an α-amylase gene (αAmy8) promoter and secreted under sucrose starvation. OsDp2Fve was partially purified from the cultured medium. The conformation of Der p 2 in OsDp2Fve remains intact as reflected by its unaltered allergenicity, as assessed by human IgE ELISA and histamine release assays, compared to non-fusion Der p 2 protein. Furthermore, the Fve protein expressed in OsDp2Fve retains its in vitro lymphoproliferative activity but loses its hemagglutination and lymphoagglutination effects compared to the native protein. Notably, in vivo evaluation showed that mice administered with OsDp2Fve possessed an enhanced production of Der p 2-specific IgG antibodies without potentiating the production of Der p 2-specific IgE and Th2 effector cytokines in comparison with mice co-administered with native Fve and Der p 2 proteins. These results suggest that the recombinant Der p 2-Fve fusion protein produced in rice suspension cell cultures has a great potential for allergy immunotherapy.

Early onset wheeze associated with enhanced combined IL-1β, IL-6, and IL-12/IL-23p40 in LPS-stimulated cord blood mononuclear cells.

Background Neonates with a family history of atopy are at higher risk for developing wheezing in early life.

Hyper-responsive T-cell cytokine profile in association with development of early childhood wheeze but not eczema at 2 years

BACKGROUND Eczema is a known risk factor for the development of wheeze in childhood. Cord blood T-cell cytokine responses have been shown to be associated with the development of both early childhood eczema and wheeze. Our objective is to study and compare the influence of intrinsic T-cell cytokine responses on the development of wheezing and eczema in the first 2 years of life in a birth cohort of at risk (first degree family with atopic disease) infants. METHODS Cord blood samples were collected from 195 eligible subjects of a birth cohort of 253 subjects. The subjects studied were those who developed either wheezing (n = 34) or eczema (n = 29) in the first 2 years of life, and 65 healthy infants served as control. Cytokines from phytohaemagglutinin stimulated mononuclear cells were analyzed using multiplex cytokine assays and the cytokine profiles in the 3 groups were compared. RESULTS Most of the subjects were non-atopic with only 3/34 (9%) wheeze and 9/29 (31%) eczema subjects sensitized to the common dietary or inhalant allergens. After adjustment for potential risk factors, wheeze, but not eczema subjects, presented with hyper-responsive cytokine profiles with increased production of T-cell cytokines IL-2 and IL-5. IL-5 was the strongest risk factor associated to the development of wheeze at 2 years of age (OR, 35; 95% CI, 5.0 -246.7). CONCLUSION Cord blood cytokine responses in early onset wheeze and eczema are distinctly different. This suggests that the tendency to develop early onset wheeze may be influenced by preexisting immune factors independent to those for eczema.

An unusual cause of food-induced anaphylaxis in mothers

BackgroundGalacto-oligosaccharides (GOS) are prebiotics added to commercial milk formula of infants and mothers. In recent years, cases of allergy related to GOS in atopic children have been reported in the South East Asian region.Case presentationsWe describe a series of pregnant (n = 4) and lactating mothers (n = 2) who developed anaphylactic reactions after consumption of maternal milk formula containing GOS. All six subjects had pre-existing atopy and a positive skin prick test to GOS and 5/5 of the subjects who were tested had positive basophil activation tests to GOS. All of the mothers and their babies had normal neonatal outcomes after the reactions.ConclusionsThe supplementation of GOS into milk and beverages in the Asian region should take into account the rare chance of allergenicity of GOS in the atopic population.