NANOPHYSIOLOGY OF CELLS, CHANNELS AND NUCLEAR PORES - Life at the Nanoscale: Atomic Force Microscopy of Live Cells - page 124

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Figure 6.6. Histogram of CFTR distribution on human red blood cells. Single-molecule
counting of Qdot-labelled CFTR molecules on RBC from ive non-CF donors and ive CF
patients (100-120 RBC membrane patches from each individual) reveals a Gaussian
distribution of CFTR within the RBC population. The histograms show peak values of
642 for non-CF-RBC (black curve) and 204 for CF patients (red curve), respectively.
The isolated membrane patches represent approximately 40% of the RBC membrane,
and the results were extrapolated to the total RBC surface area of 130 μm². 10

Quantiication of Qdots on non-CF RBC membranes revealed a mean value
of about 650 CFTR molecules per RBC. In contrast, in CF patients, we found
only about 200 CFTR molecules per RBC ( Fig. 6.6 ) . Assuming that each Qdot
represents a single CFTR molecule, we could determine a CFTR density of ~5
CFTR per μm² for non-CF RBC and of ~1.6 CFTR per μm² for RBC from CF