I am currently doing some historical studies if the vitamin hypothesis fits also the temporal relationship of allergy prevalence. While ordering RKI files for my next trip to the Berlin document center, I found that farming and lower allergy sensitization is known much longer than I anticipated. Continue reading Time to give Blackley the credit he deserves
Tag Archives: farming
Lactase variants in Europe – any connection to allergy?
I will present this poster next Monday in San Francisco at the Annual Conference of the American Thoracic Society. Continue reading Lactase variants in Europe – any connection to allergy?
Allergy research 1900-1933
Here is a brief summary of allergy research as an index to Schadewaldt
1900 Posselt (1:370; 4:44)
enteritis membranacea used synonymous to asthma
1902 Kratschmer (2:100)
hay fever is triggered by trigeminus reflex Continue reading Allergy research 1900-1933
Allergy and DC antigen processing: vitamin versus hygiene hypothesis
Last week Science has an update on differential antigen processing by DCs including a key sentence on immature DCs:
Cultured immature DCs capture antigen but only process and present it on MHC II after exposure to inflammatory stimuli or TLR ligation.
Although the authors were not aware of current allergy research, they perfectly summarize how vitamin D renders DC immature, while hygiene (infections or LPS farm exposure ) may antagonize it.
Innate immunity is species-, individual, organ-specific
In a previous paper I have questioned if LPS
nanogram exposure on the pulmonary epithelium will supersede the gram-wise exposure on the gut mucosa.
This may indeed work as now shown by Eyal Raz in a commentary in Nature Immunology where previous TLR studies
typically reproduce the splenic version of innate immunity (the spleen is used here as a metaphor for the sterile internal environment).
In the lung only the alveolar space is thought to be sterile while macrophages should not be in a constant state of activation (as inflammation would compromise gas exchange).
There are now several indicators for a lung-specific regulation of innate immunity: TLR9 is expressed in human plasmacytoid dendritic cells while TLR4 is only on myeloid DCs; TGFB-ß mediated crosstalk between alveolar macrophages and epithelial cells seems to be unique in the lung; in addition indeolamine induction or surfactant production is not found elsewhere. Yea, yea.
Is “vitamin” D a biological hub?
Folllowing up numerous emails to my recent review about allergy and vitamin D exposure, I wonder if there could be a quantitative relationship if we look at the vitamin D system as a major biological hub. This is not so much about connecting different playgrounds but of integrating signals (as shown in the hourglass blog). The East-West German difference, the farming studies as well as numerous other studies would even allow a quantitative effect. Yea, yea.
Addendum
Biospektrum will publish in their next issue a summary of the vitamin D story.
Addendum
4-07-2007 The list of vitamin D dependent genes that are associated with allergy (IL12B, IL12RB, SPP/OPN, CD14, CD23, VDR, TNF, GC, IFN, IL1RN, IL8, ADRB2, CARD15, IL4R, ALOX5, FLG, SOCS3) is expanding: TSLP and CD86