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Background: Orally administered milk fat enriched in conjugated linoleic acid (CLA) and trans-vaccenic acid (VA) ('enriched milk fat'), produced by supplementing the diet of pasture-fed cows with fish and sunflower oil, has been shown previously to suppress the development of allergic airway disease in mice., Objective: To investigate whether topical or oral application of enriched milk fat and its two major fatty acids cis-9, trans-11 CLA (c9,t11-CLA) and VA inhibit allergic dermatitis in mice., Methods: Allergic dermatitis was induced in C57BL/6 mice by epicutaneous sensitization of tape-stripped skin with ovalbumin (OVA). Enriched milk fat and its two major fatty acids were either topically applied to the OVA-sensitized skin, or orally fed to mice by supplementation of the diet. Blood and skin tissues were collected for analysis after the third skin sensitization., Results: Both topical and oral administration of enriched milk fat and its two major fatty acids led to significant suppression of allergic dermatitis as evidenced by reduced clinical and histological scores of affected skins, infiltration of inflammatory cells, and circulating allergen-specific IgE levels, compared with treatment with normal milk fat or the base control diet. C9,t11-CLA and VA individually inhibited multiple facets of allergic dermatitis when topically applied, and their combination produced a strong additive effect., Conclusion and Clinical Relevance: Enriched milk fat, and its two major fatty acids c9,t11-CLA and vaccenic acid attenuate allergic dermatitis in mice., (© 2011 Blackwell Publishing Ltd.)

Background: It has been argued that a reduction in the Western diet of anti-inflammatory unsaturated lipids, such as n-3 polyunsaturated fatty acids, has contributed to the increase in the frequency and severity of allergic diseases., Objective: We investigated whether feeding milk fat enriched in conjugated linoleic acid and vaccenic acids (VAs) ('enriched' milk fat), produced by supplementing the diet of pasture-fed cows with fish and sunflower oil, will prevent development of allergic airway responses., Methods: C57BL/6 mice were fed a control diet containing soybean oil and diets supplemented with milk lipids. They were sensitized by intraperitoneal injection of ovalbumin (OVA) on days 14 and 28, and challenged intranasally with OVA on day 42. Bronchoalveolar lavage fluid, lung tissues and serum samples were collected 6 days after the intranasal challenge., Results: Feeding of enriched milk fat led to marked suppression of airway inflammation as evidenced by reductions in eosinophilia and lymphocytosis in the airways, compared with feeding of normal milk fat and control diet. Enriched milk fat significantly reduced circulating allergen-specific IgE and IgG1 levels, together with reductions in bronchoalveolar lavage fluid of IL-5 and CCL11. Treatment significantly inhibited changes in the airway including airway epithelial cell hypertrophy, goblet cell metaplasia and mucus hypersecretion. The two major components of enriched milk fat, cis-9, trans-11 conjugated linoleic acid and VA, inhibited airway inflammation when fed together to mice, whereas alone they were not effective., Conclusion: Milk fat enriched in conjugated linoleic and VAs suppresses inflammation and changes to the airways in an animal model of allergic airway disease.

Background and Aim: Toll-like receptors (TLRs) have been identified as susceptibility genes for Crohn's disease (CD) in some, but not all, studies. Here we examined the association between candidate disease-susceptibility polymorphisms in the TLR2, TLR4 and TLR9 genes and CD in a New Zealand Caucasian population., Methods: The frequency of gene polymorphisms was examined in 182 CD patients and in 188 ethnically matched controls by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis., Results: We could not detect any significant difference in the allele frequencies of polymorphisms in the TLR2 (R753Q, 0.029 vs 0.016, P = 0.25), TLR4 (D299G and T399I, 0.085 vs 0.071, P = 0.49; and 0.085 vs 0.082, P = 0.90), and TLR9 (-1237T/C, 0.154 vs 0.148, P = 0.82) genes between controls and patients, respectively. There was no evidence that the variant TLR alleles were associated with disease phenotype. However, combination of the datasets of published studies with our dataset confirmed that the TLR4 polymorphism 299G (P = 0.0005; OR of 1.42 [95% CI 1.17-1.74]) and the TLR9 polymorphism -1237C (P = 0.0416; OR of 1.33 [95% CI 1.01-1.75]) are associated with CD., Conclusions: There was no evidence that the above variants of the TLR2, TLR4 and TLR9 genes are major risk factors for CD or influence disease phenotype in our New Zealand case-control study. Nevertheless, the significance of the TLR4 299G and TLR9-1237C associations with CD worldwide was confirmed by a meta-analysis test using our datasets and datasets from previously published studies.

Background and Aim: Crohn's disease (CD) is a complex polygenetic inflammatory disease of the bowel. NFKBIA (IkappaBalpha) is a downstream regulator of NF-kappaB, which is an effector of the major Crohn's susceptibility gene CARD15/NOD2. ICAM-1 is an integrin ligand and vascular addressin, which contributes to the trafficking of pathogenic leukocytes into the inflamed bowel. Here we examined whether the NFKBIA 2758G/A and ICAM-1 K469E variants, recently shown to be CD susceptibility genes in Caucasian populations in Germany and the United Kingdom, are associated with CD in Caucasian patients in New Zealand., Methods: PCR-RFLP analysis was used to examine the frequency of gene polymorphisms in 182 CD patients and 188 ethnically matched controls., Results: There was no significant evidence of a difference in the allele frequency of either the 2758G/A polymorphism in NFKBIA (0.38 vs 0.35, P = 0.47) or the K469E polymorphism in ICAM-1 (0.43 vs 0.37, P = 0.10) between CD patients and controls. Nevertheless, the ICAM-1 469E allele significantly (P = 0.016, Pc = 0.047) influenced the age of diagnosis of CD. Meta-analysis with five other studies confirmed a lack of association of the K469E polymorphism with Crohn's disease (P = 0.33; OR = 0.93; 95% CI, 0.82-1.07)., Conclusion: The NFKBIA 2758G/A and ICAM-1 K469E polymorphisms are not significant risk factors for CD in New Zealand; however, there is evidence that the latter polymorphism influences the age of diagnosis.

MAdCAM-1 is a high endothelial venule adhesion molecule composed of immunoglobulin and mucin-like domains which binds the leucocyte integrin LPAM-1 (alpha 4 beta 7), and is largely responsible for the selective homing of lymphocytes to mucosal tissues. A novel soluble form of mouse MAdCAM-1 which is normally membrane bound has been produced by joining the extracellular region of the receptor to the Fc domain of human IgG1. The MAdCAM-1-Fc cDNA was inserted into the genome of Autographa californica nuclear polyhedrosis virus (AcNPV). Spodoptera frugiperda insect cells infected with the recombinant virus produced MAdCAM-1-Fc as a disulfide-linked homodimer of 82 kDa polypeptides, which was secreted into the culture medium at > 1 microgram/ml. The product purified by Protein G-Sepharose was identified as authentic MAdCAM-1-Fc by the anti-MAdCAM-1 monoclonal antibody (MoAb) MECA-367 using Western blot and ELISA analysis. When immobilized on glass it was fully functional in supporting the binding of mouse alpha 4 beta 1+ alpha 4 beta 7+ mesenteric lymph node lymphocytes, and the alpha 4 beta 1- alpha 4 beta 7+ TK1 T cell lymphoma. Binding was enhanced by Mn(++)-induced integrin activation, and specifically blocked by anti-integrin alpha 4 subunit and anti-MAdCAM-1 MoAbs. Binding was blocked by pretreatment of cells with sodium azide, and EDTA, indicating that binding is an energy-dependent process which requires divalent cations. Thus the mouse MAdCAM-1-Fc chimera produced in insect cells retains certain functional properties that typify the native receptor, and should be valuable in analysing the role of MAdCAM-1 in lymphocyte recirculation and emigration. However it was not sialylated despite being post-translational modified with N- and O-linked carbohydrate moieties, suggesting that the ability of MAdCAM-1 to support cell adhesion under static conditions is sialylation-independent. A rabbit polyclonal antibody raised against the entire cytoplasmic domain of the human integrin beta 7 subunit recognized LPAM-1-like molecules in human, rat, and mouse cells, suggesting a high degree of conservation of the MAdCAM-1 receptor across species. In agreement with this notion MAdCAM-1-Fc immobilized on glass was fully functional in supporting the cation-dependent binding of peripheral blood or spleen cells from a range of other species including human, rat, and guinea pig; and for human myeloid HL60 cells, binding was mediated by alpha 4 integrins.