Figure 2.

Binding of anti-CD8α mAb to monocytes is independent of FcR. A, Blockade of Ig binding to CD64 with anti-CD64 mAb decreases binding of isotype mAb but not anti-CD8α mAb to monocytes. Bracketed numbers are geometric means of indicated peaks. B, Western blot with anti-CD8α D9 detects a 32 kDa protein as expected for CD8α in THP-1, peripheral blood lymphocytes, thymus lysate, peripheral blood monocytes (>99%), GM-CSF differentiated Mφ, PBMC, thymus, and a CTL clone but not in the lung epithelial line A549 (CD8α negative control). Right, anti-CD8α mAb B9.11 detects a 32 kDa protein as expected for CD8α in THP-1 and peripheral blood lymphocytes. 1–1.5 × 10⁶ cell equivalents were loaded in each lane.