A new function of chemical signals called 'chemokines' is revealed in a study in the March issue of Nature Immunology.
Chemokines were previously believed to function solely as guides for immune cells moving from the circulation to tissues, but this new research shows that chemokines can also cause the release of immune cells from niches such as the bone marrow.
Studies on chemokine function have focused on their role in attracting immune cells, such as inflammatory monocytes, to specific sites in the body. Homing of monocytes to the spleen during infection, for example, was previously thought to occur by chemokine attraction of monocytes that express the protein CCR2, a chemokine-responsive molecule on the surface of the cells. Work by Serbina and Pamer instead shows that monocytes require CCR2 for release from bone marrow niches where they are produced. After release into the circulation, the cells travel to the spleen without further requirement for CCR2.
These new data identify a previously unknown function for chemokines as 'gatekeepers' in addition to their known function in controlling the movement of immune cells.
Dr. Natalya Serbina (Memorial Sloan-Kettering Institute, NY USA)
Dr. Eric G. Pamer (Memorial Sloan-Kettering Institute, NY USA)
Additional contact for comments on paper:
Dr. Barrett Rollins (Dana Farber Cancer Institute, Boston, MA, USA)
Abstract available online.
(C) Nature Immunology press release.
Message posted by: Trevor M. D'Souza