Fatty and allergy a fishy story? JOHAN CARLSSON, Nutritionist / PhD student UNIVERSITY OF GOTHENBURG Sahlgrenska Academy Institute of Biomedicine Department of Infectious Diseases johan.carlsson@microbio.gu.se Supervisors: Sofia Östman (GU), Agnes Wold (GU), Ann-Sofie Sandberg (Chalmers)
Nutrition and Immunology combined Fatty Saturated Monounsaturated Polyunsaturated (PUFAs) Omega-3 α-linolenic acid EPA DHA Omega-6 Linoleic acid Arachidonic acid Overreaction towards harmless agents Picture: ImVisioN Therapeutics AG, http://www.imvisiontherapeutics.com/page2.asp?pageid=671 - -Fatty ω- in 2
is increasing worldwide but has stabilized in Sweden Asthma prevalence has increased by 50% every decade during the last 40 years 235-300 million people affected Last 20 years: No or little increase in highprevalence countries 10-15 % have atopic asthma in Sweden Continued increase in previous lowprevalence countries - -Fatty ω- in 3
A gradual switch in fatty acid consumption Worldwide trend USA, United Kingdom, Australia, New Zealand, Germany, Finland, Sweden, Japan More margarine and vegetable oils (omega-6 PUFAs) Less butter and fish (saturated fat and omega-3 PUFAs) - -Fatty ω- in 4
The balance between PUFAs affects allergy? Omega-6 Omega-3 Linoleic acid Arachidonic acid Several pro-inflammatory mediators More IgE and a Th2-skewed and allergy-prone immune system? Cause or aggravate allergy? α-linolenic acid EPA and DHA Less active inflammatory mediators + Inhibited incorporation of arachidonic acid into cell membranes etc. Protect against allergy? - -Fatty ω- in 5
Conflicting and inconclusive results Methodology? Biological properties of fatty? Local intake differences Relative or absolute levels Measured intake Specific or groups of fatty /fats/foods? Dose and timing? Length of intake periods? Effect on sensitization rather than disease Timing of intake Immature immune system is a window of opportunity Inverse relationship in utero and in childhood vs. adulthood - -Fatty ω- in 6
Have fatty the capacity to affect antigenpresenting cells influence on T cells in? Dendritic cells + antigen and fatty acid Culture + antigen-specific T cells Co-culture FACS-analysis of T cells % Proliferated T cells 100 80 60 40 20 0 alpha-linolenic acid Arachidic acid Docosahexaenoic acid Eicosapentaenoic acid Linoleic acid Oleic acid Palmitic acid Stearic acid - -Fatty ω- in 7
DHA induces a different response in T cells compared to other fatty - -Fatty ω- in 8
PUFA proportion in cord blood correlates with allergy at age 13 Is there a correlation between fatty and cytokines? Multiplex analysis of 48 cytokines in cord blood from 25 children in each group No differences of cytokine levels between the groups Weak correlation between levels of fatty and cytokines Unpublished data from Malin Barman, Chalmers - -Fatty ω- in 9
In conclusion... Fatty and their derivatives have several effects on the immune system and on allergic diseases and those effects are more complex than was previously believed JOHAN CARLSSON, Nutritionist / PhD student UNIVERSITY OF GOTHENBURG Sahlgrenska Academy Institute of Biomedicine Department of Infectious Diseases johan.carlsson@microbio.gu.se - -Fatty ω- in 10