Impressive results in overcoming allergies

Yesterday ScienceDaily published a press release about a new technique of developing immune tolerance of anaphylaxis-causing allergens in mice. The treatment resulted in significant effects with just one treatment in 90% of test cases.

The discovery involves generating a type of naturally occurring immune cell that sends a signal to reverse the hyper-immune response present in allergic reactions. That signal triggers another "off switch" that turns off reactive cells further along the allergic pathway.*Here's how the technique works:
•The key component of this research is dendritic cells, which serve as the gate-keepers of the immune system and are present in tissues in contact with the external environment, such as the skin and the inner lining of the nose, lungs, stomach and intestines.
•Gordon's pioneering treatment involves producing dendritic cells in a test tube and then exposing them to a unique mix of proteins, a vitamin A-related acid naturally occurring in the human gut, and to the allergen, in this case, peanut or ovalbumin (egg white protein). The modified dendritic cells are then reintroduced into the mouse.
•Using this technique, the researchers were able to nearly eliminate the allergic reaction by converting allergen-sensitive immune cells into cells that mimic the response seen in healthy, non-allergic individuals.
The treatment reduced the observed symptoms of anaphylaxis, and lowered other key protein markers in the allergic response by up to 90 per cent.

https://www.sciencedaily.com/releases/2016/10/161026133229.htm

Per the abstract, they "generated and characterized mature retinoic acid-skewed dendritic cells." (http://www.jacionline.org/article/S0091-6749(16)30969-1/abstract) I can't read the whole study, but I'm very curious about what exactly they did with the retinoic acid. A few months ago, I hypothesized that excess retinoic acid was connected to developing food allergies (http://petticoatgovernment.blogspot.com/2016/07/celiac-food-allergies-connected-to.html) and not in an inverse way; I thought that too much retinoic acid and its precursor retinal were interfering with RALDH2 activity, which appears crucial to immune tolerance. Perhaps I erred lumping retinal and retinoic acid together, or perhaps the timing of the exposure of the retinoic acid is crucial to developing the right kind of dendritic cell for reversing allergy. Or maybe while some retinoic acid is necessary to immune tolerance, an excess of retinoic acid causes the same problems as a deficiency, such as in this mouse study on excess Vitamin A, which found that it resulted in lower RALDH transcription subsequently - http://www.pnas.org/content/109/34/13668.full.pdf). I will have to wait until the study has been published (it's still an "article in press") to evaluate whether my hypothesis is either weakened or strengthened by the success of this new technique. Either way, I'm pleased to see such solid progress in this field!