Trichuris trichiura, which is related to T. murisWIKIMEDIA, DELORIEUX/JOHANN GOTTFRIED BREMSERVitamin A deficiency is associated with several health problems including night blindness and increased asthma risk. And as with other nutritional deficiencies, it is also known to compromise adaptive immunity mediated by the specialized T cells of the immune system. So it came as a surprise when researchers found that vitamin A deficiency could also activate the immune system and help protect mice against worm infections. Their work was published in Science today (January 23).
Yasmine Belkaid from the National Institute of Allergy and Infectious Diseases and her colleagues were examining the effects of vitamin A deficiency on the intestinal populations of two types of mouse innate immune cells—innate lymphoid cells 2 and 3 (ILC2, ILC3), which play major roles in maintaining “barrier immunity,” the first line of defense at surfaces exposed to the environment, such as the intestine and skin—when they found this unexpected result. When the researchers blocked the active metabolite of vitamin A, retinoic acid, ILC3 cell populations diminished as expected. But ILC2 cell populations swelled.
Describing the work as “an elegant series of experiments,” Richard Grencis, a professor of immunology and microbiology at the University of Manchester who was not involved in the work, told The ...
