Hopefully the auto-loader at the bottom will pick some previous posts here about calcium, vitamin D and allergy; these may be necessary for the background of a new study published in the American Journal of Respiratory and Critical Care Medicine last week

We looked for Cav1 channel expression in Th2 and Th1-cells by real-time PCR and Western blotting. We sequenced the isoforms expressed by Th2-cells and tested whether Cav1 antisense oligodeoxynucleotides (Cav1AS) affected Ca2+ signaling and cytokine production [...] mouse Th2 but not Th1-cells expressed Cav1.2 and Cav1.3 channels. Th2-cells transfected with Cav1AS had impaired Ca2+ signaling and cytokine production, and lost their ability to induce airway inflammation upon adoptive transfer.

This highlights again the close connection of the calcium system to immunology. While the earlier
TRPM4 story was basically about mast cells, we now arrived at Th2 cells, yea, yea.

What do all these places share? Spitalfriedhof Basel, Roopkund Lake, Catacombes de Paris and Central Yakuts are all examples where remains are available for genetic studies (even Tutankhamun was undergoing a paternity test recently).
More relevant will certainly be an empirical investigation if reduced selection is leading now to immune disease.

While some of my earlier co-workers continue to praise the achievements of GWAs, some other earlier co-authors now show that the common variants thrown on the current GWA chips are leading to false assocations (called politely “synthetic” associations)

We propose as an alternative explanation that variants much less common than the associated one may create “synthetic associations” by occurring, stochastically, more often in association with one of the alleles at the common site versus the other allele. Although synthetic associations are an obvious theoretical possibility, they have never been systematically explored as a possible explanation for GWAS findings. Here, we use simple computer simulations to show the conditions under which such synthetic associations will arise and how they may be recognized. We show that they are not only possible, but inevitable…

The proof comes with a sickle cell anemia study (Show me more…)

This week the journal “Allergy” printed a report of three cases where allergic sensitization in preterm infants is attributed to the human milk fortifier Similac.

The product contains: Nonfat milk, corn syrup solids, whey protein concentrate, and MCT oil (fractionated coconut or palm kernel oil) as sources of proteins, fat, and carbohydrate (Abbott Laboratories Pediatric Nutritional Products Guide, DIR/98A08, 2008, Mississauga, Canada).

Not listed above but in the Products Guide are 120 IU/100 ml D3 which may indeed function as a sensitizer.

A book review of “Why we get sick” at tennov.com writes

Bacteria can evolve as much in a day as we can in 1000 years and there are as many bacterial cells in each of our guts as there are people on earth. That even improbable mutations occur with frequency in populations of pathogens gives them a decided advantage [...] As Nesse and Williams emphasize, the end of the war is nowhere in sight. The 20th century was the golden age of relief from infection, but it may be over and this may accurately be considered a “post-antimicrobiol era.”

The same fact in Mel Greaves’ writing (p 216)

Natural selection will have operated against individuals who inherited fatal conditions that strike early in life, and for those whose immune systems were bext equipped to restrain the ravages of plagues. The geneticist and polymath, J B S Haldane, was surely correct in suggesting that infections have been the most powerful ‘natural’ selective pressure acting on human populations.

Unaware of the Haldane quote (Show me more…)

It is interesting to see, how journals are trying to increase their market visibility – Nature has becoming famous for their investment in Second Life? Just recently I received an email that JACI – the Journal of Allergy and Clinical Immunology – has now opened an account at Facebook. (Show me more…)