CLL cells circulating under physiologically relevant shear force showed increased expression of CD62L, CXCR4, CD5, CD49d, and CD69. CLL cells were circulated through the circulating system with hollow fibers lined with HUVEC cells for 48 hours. Cell surface expression of (A) CD62L, (B) CXCR4, (C) CD5, (D) CD49d, (E) CD69, (F) CD38, (G) CD80, (H) MMP-9, and (I) CD19 was measured by flow cytometry gated on doublet-discriminated lymphocytes represented as mean fluorescence intensity (MFI) values (**P < .0001; *P < .05).