PT  - JOURNAL ARTICLE
AU  - Haile, Lydia A.
AU  - Gamrekelashvili, Jaba
AU  - Manns, Michael P.
AU  - Korangy, Firouzeh
AU  - Greten, Tim F.
TI  - CD49d Is a New Marker for Distinct Myeloid-Derived Suppressor Cell Subpopulations in Mice
AID  - 10.4049/jimmunol.0903573
DP  - 2010 Jul 01
TA  - The Journal of Immunology
PG  - 203--210
VI  - 185
IP  - 1
4099  - http://www.jimmunol.org/content/185/1/203.short
4100  - http://www.jimmunol.org/content/185/1/203.full
SO  - J. Immunol.2010 Jul 01; 185
AB  - Myeloid-derived suppressor cells (MDSCs) are a heterogenous population of cells that negatively regulate the immune response during tumor progression, inflammation, and infection. In this study, through gene-expression analysis, we have identified a new marker, CD49d, which is expressed exclusively on CD11b+Gr-1dull/int. MDSCs. We have characterized two subpopulations of MDSCs based on CD49d expression in two different settings, a mouse model of inflammatory bowel disease and tumor-bearing mice. The CD49d+ subset of MDSCs was mainly monocytic and strongly suppressed Ag-specific T cell proliferation in an NO-dependent mechanism similar to Gr-1dull/int. MDSCs. Alternatively, CD49d− cells were granulocytic and poorly inhibited T cell proliferation compared with CD11b+Gr-1high cells. Both mouse models showed preferential expansion of the granulocytic CD49d− subset. We suggest that CD49d can be used as an alternative marker for Gr-1 to differentiate between the subpopulations of MDSCs together with CD11b, which will ultimately help in understanding the mechanisms of immune suppression by MDSCs.