Characteristics of the soluble form of DNAM-1.

<p>(A) The soluble form of DNAM-1 (sDNAM-1) in sera from healthy volunteers (n = 38) was measured by sandwich ELISA. (B) sDNAM-1 in human serum was detected by immunoprecipitation (IP) followed by immunoblotting (IB) with mouse anti-human DNAM-1 mAb (TX25). Cell lysate of DNAM-1/ BW transfectant was used as control of membrane DNAM-1 (mDNAM-1). (C) Peripheral blood mononuclear cells (PBMCs) from healthy volunteers were stimulated with the indicated mAbs in the presence of IL-2. sDNAM-1 in the culture supernatant was measured by ELISA on day 7 after the start of culture. (D) PBMCs from healthy volunteers were stimulated with anti-CD3 and anti-DNAM-1 mAbs. On day 3 after the start of culture, the medium was replaced with fresh medium (plain) and a broad-spectrum matrix metalloproteinase (MMP) inhibitor, GM6001 (100 μM) or TAPI-1 (50 μM), was added into the culture. On day 6, sDNAM-1 in the culture supernatant was measured by ELISA. Error bars in all panels represent the mean and standard deviation (SD). * and **, <i>P</i> < 0.05 and <i>P</i> < 0.01, respectively, compared with the sDNAM-1 concentration in the culture supernatant in the presence of IL-2 alone (C) or DMSO (0.1%) alone (D).</p

Acute GVHD characteristics (univariate analysis).

<p>Acute GVHD characteristics (univariate analysis).</p

ROC curves for patients subjected to allo-HSCT.

<p>ROC curves comparing maximal sDNAM-1 of patients with aGVHD (n = 48) with that of patients without aGVHD (n = 23) for the specified period relative to allo-HSCT (day 0).</p

Soluble DNAM-1, as a Predictive Biomarker for Acute Graft-Versus-Host Disease

<div><p>Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Because diagnosis of aGVHD is exclusively based on clinical symptoms and pathological findings, reliable and noninvasive laboratory tests for accurate diagnosis are required. An activating immunoreceptor, DNAM-1 (CD226), is expressed on T cells and natural killer cells and is involved in the development of aGVHD. Here, we identified a soluble form of DNAM-1 (sDNAM-1) in human sera. In retrospective univariate and multivariate analyses of allo-HSCT patients (n = 71) at a single center, cumulative incidences of all grade (grade I–IV) and sgrade II–IV aGVHD in patients with high maximal serum levels of sDNAM-1 (≥30 pM) in the 7 days before allo-HSCT were significantly higher than those in patients with low maximal serum levels of sDNAM-1 (<30 pM) in the same period. However, sDNAM-1 was not associated with other known allo-HSCT complications. Our data suggest that sDNAM-1 is potentially a unique candidate as a predictive biomarker for the development of aGVHD.</p></div