PT  - JOURNAL ARTICLE
AU  - Kitano, Shigehisa
AU  - Postow, Michael A.
AU  - Ziegler, Carly G.K.
AU  - Kuk, Deborah
AU  - Panageas, Katherine S.
AU  - Cortez, Czrina
AU  - Rasalan, Teresa
AU  - Adamow, Mathew
AU  - Yuan, Jianda
AU  - Wong, Philip
AU  - Altan-Bonnet, Gregoire
AU  - Wolchok, Jedd D.
AU  - Lesokhin, Alexander M.
TI  - Computational Algorithm-Driven Evaluation of Monocytic Myeloid-Derived Suppressor Cell Frequency for Prediction of Clinical Outcomes
AID  - 10.1158/2326-6066.CIR-14-0013
DP  - 2014 Aug 01
TA  - Cancer Immunology Research
PG  - 812--821
VI  - 2
IP  - 8
4099  - http://cancerimmunolres.aacrjournals.org/content/2/8/812.short
4100  - http://cancerimmunolres.aacrjournals.org/content/2/8/812.full
SO  - Cancer Immunol Res2014 Aug 01; 2
AB  - Evaluation of myeloid-derived suppressor cells (MDSC), a cell type implicated in T-cell suppression, may inform immune status. However, a uniform methodology is necessary for prospective testing as a biomarker. We report the use of a computational algorithm-driven analysis of whole blood and cryopreserved samples for monocytic MDSC (m-MDSC) quantity that removes variables related to blood processing and user definitions. Applying these methods to samples from patients with melanoma identifies differing frequency distribution of m-MDSC relative to that in healthy donors. Patients with a pretreatment m-MDSC frequency outside a preliminary definition of healthy donor range (<14.9%) were significantly more likely to achieve prolonged overall survival following treatment with ipilimumab, an antibody that promotes T-cell activation and proliferation. m-MDSC frequencies were inversely correlated with peripheral CD8+ T-cell expansion following ipilimumab. Algorithm-driven analysis may enable not only development of a novel pretreatment biomarker for ipilimumab therapy, but also prospective validation of peripheral blood m-MDSCs as a biomarker in multiple disease settings. Cancer Immunol Res; 2(8); 812–21. ©2014 AACR.