Nutritional Interventions to Prevent the Development of Atopic Diseases: A Focus on Cow's Milk Allergy

In the western world the prevalence of atopic diseases such as food allergies is increasing highly significantly. One of the earliest and most prevalent food allergies occurring in the first year of life is cow's milk allergy. No treatment is available and only avoidance of the cow's milk allergens prevents the occurrence of an allergic reaction. Since cow's milk allergic children have an increased risk of developing other allergies later in life, investigating nutritional strategies to prevent the development of cow's milk allergy by developing oral tolerance is of high interest. Nutritional components such as prebiotics, probiotics, synbiotics and long-chain polyunsaturated fatty acids possess potential to support the maturation of the immune system early in life that might prevent the development of cow's milk allergy. The available research, so far, shows promising results particularly on the development of eczema. However, the preventive effects of the nutritional interventions on the development of food allergy are inconclusive. Future research may benefit from the combination of various dietary components. To clarify the preventive effects of the nutritional components in food allergy more randomized clinical trials are needed

Modulation of gut-immune-brain axis by non-digestible oligosaccharides and omega-3 fatty acids in health and allergic disease: Synergy or rivalry?

In early life, the intestinal microbiota undergoes a tremendous maturation and if disturbed this has been associated with negative effects on immune and brain development. Healthy microbiome maturation is supported by components like prebiotics like short-chain galacto-oligosaccharides (scGOS) and long-chain fructo-oligosaccharides (lcFOS) and omega-3 polyunsaturated fatty acids (n-3 PUFAs), which are present in infant formula milk to mimic human breast milk. The aim of this thesis was to evaluate the additional effects of a dietary combination of scGOS:lcFOS and n-3 PUFAs to improve health as well as to prevent cow’s milk allergy (CMA) development. In healthy mice, the combination of scGOS:lcFOS and n-3 PUFAs altered the intestinal bacterial composition in a distinct manner compared to the effects of the compounds individually. Additionally, scGOS:lcFOS improved social behaviour and reduced anxiety-like and repetitive behaviour, however, the n-3 PUFA and the combined interventions had limited to no effect on the evaluated behaviours and immune system parameters. CMA development was partly prevented by scGOS:lcFOS or n-3 PUFAs in mice but no additional effect was observed by the combination. Splenic cytokine responses were reduced and caecal butyrate level was induced by scGOS:lcFOS which tended to be impaired when combined with n-3 PUFAs, indicating the individual effects seemed to be negatively impacted when combined. It could also suggest a possible interaction between the dietary components, which was evaluated by studying modulation of intestinal Pparɣ expression, physical and chemical interaction and modulation of intestinal bacterial fermentation. It is no option to leave scGOS:lcFOS or n-3 PUFAs out of formula milk but it is essential to evaluate individual components and combinations as they might act differently than expected

Modulation of gut-immune-brain axis by non-digestible oligosaccharides and omega-3 fatty acids in health and allergic disease: Synergy or rivalry?

In early life, the intestinal microbiota undergoes a tremendous maturation and if disturbed this has been associated with negative effects on immune and brain development. Healthy microbiome maturation is supported by components like prebiotics like short-chain galacto-oligosaccharides (scGOS) and long-chain fructo-oligosaccharides (lcFOS) and omega-3 polyunsaturated fatty acids (n-3 PUFAs), which are present in infant formula milk to mimic human breast milk. The aim of this thesis was to evaluate the additional effects of a dietary combination of scGOS:lcFOS and n-3 PUFAs to improve health as well as to prevent cow’s milk allergy (CMA) development. In healthy mice, the combination of scGOS:lcFOS and n-3 PUFAs altered the intestinal bacterial composition in a distinct manner compared to the effects of the compounds individually. Additionally, scGOS:lcFOS improved social behaviour and reduced anxiety-like and repetitive behaviour, however, the n-3 PUFA and the combined interventions had limited to no effect on the evaluated behaviours and immune system parameters. CMA development was partly prevented by scGOS:lcFOS or n-3 PUFAs in mice but no additional effect was observed by the combination. Splenic cytokine responses were reduced and caecal butyrate level was induced by scGOS:lcFOS which tended to be impaired when combined with n-3 PUFAs, indicating the individual effects seemed to be negatively impacted when combined. It could also suggest a possible interaction between the dietary components, which was evaluated by studying modulation of intestinal Pparɣ expression, physical and chemical interaction and modulation of intestinal bacterial fermentation. It is no option to leave scGOS:lcFOS or n-3 PUFAs out of formula milk but it is essential to evaluate individual components and combinations as they might act differently than expected

Preventive effects of a combination of dietary scGOS:lcFOS and n-3 PUFA in a murine cow's milk allergy model

Objectives and Study: Cow's milk allergy (CMA) affects 2% of children younger than 4 years and no effective prevention or treatment strategies are available. The dietary components short-chain galactoand long-chain fructo-oligosaccharides (scGOS:lcFOS) and omega-3 poly-unsaturated fatty acids (n-3 PUFA) have immune regulatory capacities and have been demonstrated to reduce the allergic symptoms in a murine model of CMA, however, it is unknown if an additional effect occur when these dietary components are combined. The objective of this study was to evaluate the preventive effect of a combination of scGOS:lcFOS and n-3 PUFA on CMA development in a mouse model. Method: 3-4 weeks old C3H/HeOuJ female mice received a control or a supplemented diet with 1% (9:1) scGOS:lcFOS, 6% n-3 PUFA or a combination of 1% scGOS:lcFOS and 6% n-3 PUFA (n=12-15) from day-14. For 5 weeks (day 0-28) the mice were weekly sensitized to 20 mg cow's milk whey protein in PBS with 10 ug cholera toxin (CT) or CT only (control). Clinical parameters were measured after intradermal and oral challenge. After the mice were killed (day 43) mesenteric lymph nodes (MLN), spleen and lamina propria (LP) were isolated to measure the levels of Th1 and Th2 subsets. Serum was collected to determine levels of mouse mast cell protease 1 (mMCP-1) and antigen specific immunoglobulins. Results: The scGOS:lcFOS diet or n-3 PUFA diet reduced the acute allergic skin response significantly. The combination diet showed no significant reduction of the acute allergic skin response. All the tested diets caused no significant reduction in CMA-induced mMCP-1 and immunoglobulins IgE, IgG1 and IgG2a serum levels. Th1 and Th2 subsets in spleen, MLN and LP were neither affected by CMA nor by the dietary supplementations. Conclusion: A dietary supplementation with scGOS:lcFOS or n-3 PUFA in a preventive setting reduce the acute allergic skin response in CMA mice. No additional effect was observed when these components were combined. CMA appeared to have no influence on Th1 and Th2 subsets in spleen and gut-associated lymphoid organs

Preventive effects of a combination of dietary scGOS:lcFOS and n-3 PUFA in a murine cow's milk allergy model

Objectives and Study: Cow's milk allergy (CMA) affects 2% of children younger than 4 years and no effective prevention or treatment strategies are available. The dietary components short-chain galactoand long-chain fructo-oligosaccharides (scGOS:lcFOS) and omega-3 poly-unsaturated fatty acids (n-3 PUFA) have immune regulatory capacities and have been demonstrated to reduce the allergic symptoms in a murine model of CMA, however, it is unknown if an additional effect occur when these dietary components are combined. The objective of this study was to evaluate the preventive effect of a combination of scGOS:lcFOS and n-3 PUFA on CMA development in a mouse model. Method: 3-4 weeks old C3H/HeOuJ female mice received a control or a supplemented diet with 1% (9:1) scGOS:lcFOS, 6% n-3 PUFA or a combination of 1% scGOS:lcFOS and 6% n-3 PUFA (n=12-15) from day-14. For 5 weeks (day 0-28) the mice were weekly sensitized to 20 mg cow's milk whey protein in PBS with 10 ug cholera toxin (CT) or CT only (control). Clinical parameters were measured after intradermal and oral challenge. After the mice were killed (day 43) mesenteric lymph nodes (MLN), spleen and lamina propria (LP) were isolated to measure the levels of Th1 and Th2 subsets. Serum was collected to determine levels of mouse mast cell protease 1 (mMCP-1) and antigen specific immunoglobulins. Results: The scGOS:lcFOS diet or n-3 PUFA diet reduced the acute allergic skin response significantly. The combination diet showed no significant reduction of the acute allergic skin response. All the tested diets caused no significant reduction in CMA-induced mMCP-1 and immunoglobulins IgE, IgG1 and IgG2a serum levels. Th1 and Th2 subsets in spleen, MLN and LP were neither affected by CMA nor by the dietary supplementations. Conclusion: A dietary supplementation with scGOS:lcFOS or n-3 PUFA in a preventive setting reduce the acute allergic skin response in CMA mice. No additional effect was observed when these components were combined. CMA appeared to have no influence on Th1 and Th2 subsets in spleen and gut-associated lymphoid organs

Superior Cervical Ganglia Neurons Induce Foxp3+ Regulatory T Cells via Calcitonin Gene-Related Peptide.

The nervous and immune systems communicate bidirectionally, utilizing diverse molecular signals including cytokines and neurotransmitters to provide an integrated response to changes in the body's internal and external environment. Although, neuro-immune interactions are becoming better understood under inflammatory circumstances and it has been evidenced that interaction between neurons and T cells results in the conversion of encephalitogenic T cells to T regulatory cells, relatively little is known about the communication between neurons and naïve T cells. Here, we demonstrate that following co-culture of naïve CD4+ T cells with superior cervical ganglion neurons, the percentage of Foxp3 expressing CD4+CD25+ cells significantly increased. This was mediated in part by immune-regulatory cytokines TGF-β and IL-10, as well as the neuropeptide calcitonin gene-related peptide while vasoactive intestinal peptide was shown to play no role in generation of T regulatory cells. Additionally, T cells co-cultured with neurons showed a decrease in the levels of pro-inflammatory cytokine IFN-γ released upon in vitro stimulation. These findings suggest that the generation of Tregs may be promoted by naïve CD4+ T cell: neuron interaction through the release of neuropeptide CGRP

SCG-neurons increase the frequency of Foxp3⁺ T cells.

<p>Total splenocytes were co-cultured with SCG-neurons for 5 days and stained with antibodies against CD3, CD4, CD25, and Foxp3; and analyzed by flow cytometry. (A) Representative dot plots and (B) mean ± SEM percentage of Foxp3⁺ cells among the CD3⁺CD4⁺CD25⁺ cells are depicted. (C) Mean ± SEM percentage of Foxp3⁺ cells among the CD3⁺CD4⁺CD25⁺ cells in different time points in the co-culture is shown. (n = 4; *p<0.0001).</p

Alterations in regulatory T cells induced by specific oligosaccharides improve vaccine responsiveness in mice.

UnlabelledProphylactic vaccinations are generally performed to protect naïve individuals with or without suppressed immune responsiveness. In a mouse model for Influenza vaccinations the specific alterations of CD4(+)CD25(+)Foxp3(+) regulatory T-cells (Tregs) in the immune modulation induced by orally supplied oligosaccharides containing scGOS/lcFOS/pAOS was assessed. This dietary intervention increased vaccine specific DTH responses. In addition, a significant increased percentage of T-bet(+) (Th1) activated CD69(+)CD4(+) T cells (pIn conclusionThese data are indicative for improved vaccine responsiveness due to reduced Th1 suppressive capacity in the Treg population of mice fed the oligosaccharide specific diet, showing compartmentalization within the Treg population. The modulation of Tregs to control immune responses provides an additional arm of intervention using alternative strategies possibly leading to the development of improved vaccines

SCG-neurons generate Tregs from naïve T cells that is potentiated by IL-2.

<p>Purified CD4⁺ T cells or CD4⁺CD62L⁺ naïve T cells from total splenocytes from BALB/c mice were co-cultured with SCG-neurons and stained with antibodies against CD3, CD4, CD25 and Foxp3; and analyzed by flow cytometry. (A) Mean ± SEM percentage of Foxp3⁺ cells among the CD3⁺CD4⁺CD25⁺ cells are depicted. (CD4⁺ T cells n = 5, CD4⁺CD62L⁺ cells n = 5; * = p<0.0001). (B) Mean ± SEM percentage of Foxp3 expressions in CD3⁺CD4⁺CD25⁺ cells in the co-cultures in presence or absence of IL-2 are shown (n = 5, * = p<0.0001).</p

CGRP but not VIP contributes to the generation of Foxp3⁺ Tregs by SCG-neurons.

<p>Neuron cultures were incubated with neutralization antibodies for TGF-β, IL-10, or VIP, and CGRP antagonist for one hour before adding T cells. The co-cultures were incubated for 5 days and T cells were stained for CD3, CD4, CD25 and Foxp3 and were analyzed using flow cytometry. Mean ± SEM percentage of Foxp3 expression among CD3⁺CD4⁺CD25⁺ cells in different co-cultures are shown. (n = 6, ** = p<0.002, *** = p<0.0002).</p