A new American research on human cells has found a molecule thymic stromal lymphopoietin (TSLP), which directs immune cells to develop the ability to generate an allergic response.
The study suggests that this molecule is vital to the development of allergic diseases like asthma, atopic dermatitis (eczema), and food allergy.
A team of researchers led by Yong-Jun Liu at the University of Texas M.D. Anderson Cancer Center, Houston, studied dendritic cells, immune cells that kick off the primary immune response.
Dendritic cells come into contact with other immune cells the T cells, causing them to transform into different subsets of T cells, including helper 1 (Th1) and helper 2 (Th2) cells.
These T-cell subsets are concerned with protective immune responses, but the Th2 cells can also drive an allergic response. Until now the process by which the dendritic cells prompted T cells to become Th2 cells was not known.
The scientists used dendritic cells taken from the blood of healthy donors and found that the binding of TSLP to these cells triggers a distinct set of signalling pathways inside the cells. Consequently, the dendritic cells produce messenger molecules that act on the T cells, causing them to develop into Th2 cells.
The study recognises TSLP as a switch that leads to the development of the allergic response in people and suggests that this molecule could be used as a potential therapeutic target for the treatment and prevention of allergic diseases.