Fig. 5 (abstract P385).

Circulating Melanoma Cell (CMC) Qrt-PCR Analysis Demonstrates Enhanced CXCR2 Ligand Expression in Progressing Melanoma Patients Following anti-PD-1/anti-PD-L1 Ab Therapy. A. Schematic showing clinical specimen acquisition and analysis work flow. Samples are harvested from patients before and during checkpoint inhibitor immunotherapy. CMCs are enriched through centrifugation, analyzed by the photoacoustic flow cytometer, and subjected to integrated fluidic chip single cell qrt-PCR analysis of select target genes. Samples positive for CD45 or negative for both MART1 and S100 are excluded from analysis. Target gene expression normalized to Ubb expression levels. 6 CMCs analyzed per patient time point. B. Spider plot of target lesion tumor volume versus time for an advanced melanoma patient undergoing anti-PD-L1 ab therapy. Blood samples taken at week 0 prior to therapy and week 24. C. MART1 immunofluoresence analysis of captured CMCs. Brightfield images shown on left. D. CMC single-cell qrt-PCR analysis and quantitation of CXCR2 ligands and other target genes of interest in the same patient described in B. Data has been normalized to week 0 expression levels of respective target genes