Abs used in flow cytometric analyses were as described in Lang et al. (2011 (link), 2013 (link)). Abs specific for mGR1 (RB6-8C5), mH-2Dd (34-2-12), mCD45 (30-F11), hCD3 (OKT3, HIT3a), hCD5 (UCHT1), hCD34 (581), hCD38 (HB-7), hCD40 (5C3), hCD45 (H130), hCD138 (Ml15), hCD268 (11C1), hIgκ (MHK-49), hIgλ (MHL-38), and hIgM (MHM-88) were from BioLegend. Abs for rat IgG1 (RG11/39.4), hCD3 (HIT3a), hCD19 (HIB19), and hIgM (G20-127) were from BD, and those for hIgκ (HP6062) and hIgM (SA-DA4) were from eBioscience. Fab′ goat anti-hIgM was from Protos Immunoresearch. Cells were stained in staining buffer (PBS, 1% BSA, 0.1% Na Azide) for 15 min at 4°C and washed twice with the same buffer. Samples were collected on CyAn analyzers (Beckman Coulter) at the flow cytometry cores at NJH or UCD Cancer Center, and analyses were performed with FlowJo software as described in Lang et al. (2013) (link).