Published on December 21, 2012 at 6:00 AM
According to the researchers, the findings establish a baseline for T-cell immunity in healthy individuals. This knowledge can be used to better understand how various tissues respond to site-specific and systemic autoimmune and inflammatory diseases. The findings can therefore powerfully inform the development of new vaccine strategies. "To make better vaccines, it may be necessary to activate a T-cell response at the site of an infection, not just in the general circulation," said Dr. Farber. "But first we have to know what types of immune cells are in those tissues and how they function. This is a first step in that direction."
To study T cells, researchers need multiple tissue samples, which cannot be taken from healthy individuals. Working with the New York Organ Donor Network, the organ procurement organization for the greater New York metropolitan area, CUMC researchers obtained tissue samples from 24 individual organ donors. Samples were taken from tissues that have direct contact with pathogens, including lymph, lung, spleen, and small and large intestines. The donors, all of whom had died suddenly of traumatic causes, ranged in age from 15 to 60. All were HIV-negative and free of cancer and other chronic or immunological diseases.
"Most of what we have known about human T cells is based on studies of the blood, because it is so accessible," said Dr. Farber. "But that is only a small sampling of the body's T cells. We already had good evidence, from mouse studies, that other tissues have their own types of T cells and that they play an important role in mediating immune protection. We wanted to find out if this was the case in humans."
Source: Columbia University Medical Center