Figure 4: Capture of circulating plasma cells in MM patient samples.

(a) Fluorescence images of captured cells stained with anti-CD138 antibody (red staining on the cell membrane) and intracellular λ antibody (green stain inside the cell). (b) Number of CPCs (CD138+ cells) captured from 1-mL samples of healthy donor blood, MM patient blood, and MM bone marrow. (c) The number of CPCs captured in the device shows excellent correlation with flow cytometry analysis. (d) Ratio of λ CPCs to total CPCs in the same samples as in (b). The 10-2 point in the “Normal Blood” column is zero (no λ+ cell detected). (e) The k/λ ratios in serum and captured cell, and the paraprotien levels, among the different MM blood samples. (f) The number of captured CD138+ cells and the corresponding serum paraprotein levels are positively correlated. (g) The estimated κ/λ ratio in captured CPCs is positively correlated with the measured serum κ/λ ratio.