A new abstract at the recent ATS congress now clears the 2007 controversy between the Camargo and Gale studies on the effect of vitamin D: Wheezing is not asthma (as the atopy component is missing?). Continue reading Not all that wheezes is asthma
Tag Archives: allergy
CD 14 now also on the vitamin+allergy list
Just for curiosity I am collecting a list of allergy genes that are vitamin D dependent. The list is already rather long but now there is a prominent addition: CD14. Known as asthma gene for many years the vitamin D dependency isn’t such clear. A clever analysis, however, now shows that there is an intermediate step involved Continue reading CD 14 now also on the vitamin+allergy list
Rough and tumble science
Over the years I have collected a lot of curious hypotheses how allergy develops. Only recently I ended this list as it became rather long – and to be polite – rather useless. Sorry, less polite – but nonsense at its best Continue reading Rough and tumble science
Where is the asthma gene?
A new paper – the second bioinfomatics approach following the groundbreaking work by Perez-Iratxeta – is now coming up with some interesting remarks beyond IL-13 and TGF-ß1 Continue reading Where is the asthma gene?
A factor in hay prevents vitamin D action
As always, a longer literature search prevents from new discoveries… Here comes a nice piece from 1952 on the antagonistic effect of LPS on vitamin D (Is that really LPS or did I interpret it wrong?). Although not included in my recent review on vitamin D and allergy – I attributed the effect to Lyakh et al. – here is the first description of this effect. Continue reading A factor in hay prevents vitamin D action
Allergy starts only after birth
Although there are numerous reports and even whole schools of thought building on a prenatal origin of allergy, a new study now clearly states that sensitization does not develop in utero. IgE traditionally measured in cord blood IgE is a contamination of maternal IgE. The authors show that there is a correlation with IgA and the “spurious specific IgE” at birth “vanishes” during the following 6 months. If you ever had a cord in hand, you will understand how easily contamination occurs.
Addendum 12/10/2008
The “prenatal origin” party doesn’t give up basically with the arguments:
- no Ig A found that would be indicative of contamination BUT unfortunately their Ig A threshold of 32 ug/mL is not really appropriate
- more than half of their cord blood samples have IgE negative mothers BUT unfortunately they don’t show the unclassified IgE values (is that’s just an artifact of a normal test variation?)
- some of their cord blood samples have higher IgE levels than the mothers BUT again the same argument of an arbitrary classification applies
- most single IgE results are not concordant between mother but they admit concordant results at least for food allergens. This may indeed been taken as an argument against simple cord blood contamination of ALL samples. As the accompanying editorial points out an in vivo translocation of immune complexes of IgG:allergen+IgE of a food allergens (that are nearly always present in contrast to some seasonal allergens) may be possible
- the discussion ignores more or less the fact that there is definitely NO concordance with the father (as shown in table I) so leakage or contamination is likely
The authors explain the maternal/fetal association “by maternal inheritance of atopic IgE responsiveness on chromosome 11q and other gene loci” BUT unfortunately there is neither atopic IgE responsiveness on chromosome 11q nor is there any evidence of imprinting. So – according to our best evidence allergy starts only after birth. To convince me it would not need 922 neonates but 1 B cell of proven fetal origin that makes IgE – making the whole story at least a good example how insufficient methods produce doubtful conclusions, yea, yea.
Vitamania
For everybody who wants to follow up the most recent discussion about allergy promoting effects of vitamin D here is a short summary. The Harvard group basically wrote three articles that were immediately contradicted. The comment on the first article in JACI was by a NIH researcher Continue reading Vitamania
Severe flaw in mouse allergy studies
A report in Biospektrum 07.07/13:762 about the production of endotoxin free ovalbumin by a German company now reveals that nearly all commercially available ovalbumin preparations are highly contaminated with endotoxin. Company A included 723, company B 1038, company C 257 and company D 342 EU/mg LPS. As all mice are usually also on a vitamin D supplement diet, recent mouse studies may have produced largely artifacts if both – agonist and antagonist – are included in an uncontrolled manner, yea, yea.
Best allergy paper 2007
The end of the year 2007 is approaching very fast. I can already vote for the best allergy paper in 2007 – it is a paper from Vienna by Victoria Leb about the molecular and functional analysis of the Ambrosia antigen T cell receptor. They have been able to isolate and transfer alpha (TRAV17-TRAJ45) and beta chain (TRBV18,TRBD1 and TRBJ2-7) TCR chains into Jurkat cells and even other human blood lymphocytes with convicing evidence that the infected cells were Ambrosia Art V1 reactive.
This opens brand new perspectives for developing a truely allergic TCR transgenic mouse that can be easily challenged and desensitized. It may even allow immediate testing of a variety of substance (and constructs) to ultimately cure allergy. My favorite is to feed DCs with antigen coupled to a T cell suicide program on succesfull antigen presentation.
Auto desensitization
Blackley found already in 1873 an interesting explanation of the “no allergy in farming children” effect by referring to some kind of auto desensitization in this particular environment – e.g. the high pollen and LPS exposure.
Do you know that a commercial allergen preparation used for desensitization already includes a LPS derivate, 3-o-desacyl-4′ monophosphoryl lipid A as an adjuvant? It is believed to push the pollen reaction into a IL12 – IFNg – Th1 pathway. This therapeutic approach already perfectly fits the early explanation of Blackley.
When will the allergy farming lobby ultimately close their files?
No proof of hygiene hypothesis
Yahoo News writes “Doubts cast on hygiene hypothesis“. As far as I know YN highlights the first experimental study of the hygiene hypothesis. Although the authors could achieve a reduction of respiratory infections by controlled randomized hygiene intervention, there was no effect on later asthma or allergy.
Vitamin A and allergy
No, I am not confusing here vitamin A and vitamin D as done in the early days of vitamin research. This post is really about vitamin A (but with similar nomenclature problem as with vitamin D). Retinol is ingested in a precursor form; animal sources like liver (–>cod liver oil) contain retinyl esters, whereas plants like carrots contain carotenoids. Continue reading Vitamin A and allergy
Time to give Blackley the credit he deserves
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
Allergy transplantation
A new paper in Transplantation takes up an old question – can you passively transfer asthma or allergy? It seems so – the current study reports in 5 of 42 patients elevated IgE plus allergy symptoms. This is in line with earlier reports. Sorry to say — you can get allergy also by bone marrow transplantation.
Addendum 10/6/08
Blood
A total of 16 nonallergic recipients with allergic donors were reported to develop allergic disease posttransplant, however, conclusive information was available for only 5 cases. Allergic disease was reported to abate in 3 allergic recipients with nonallergic donors, however, conclusive information was available for only 2 cases. Problems in interpreting the reports include incomplete data on allergic disease in the donor or recipient pretransplant, not knowing the denominator, and the lack of controls. In summary, review of the literature generates the hypothesis that allergic disease is transferable
Addendum 14/7/22
Ann All Asthma Immunol
Wormy world
Allergy (or at least an associated trait) may have its roots somewhere in Africa – where helminth infections are frequent. A new Nature Immunol Review has an overview but I am quite disappointed. From the abstract Continue reading Wormy world