Figure 3. Immunostaining of membrane-tethered CARPB with nanobodies.

(A) CARPB-expressing cells stained with nanobody-displaying phages. GFP signals mark cells expressing membrane-tethered CARPB. Nb.b201 phage, an irrelevant nanobody displaying phage, was used as negative control. BF, bright field. (B) CARPB-expressing cells stained with purified nanobodies. GFP signals label the cells expressing membrane-tethered CARPB. Nb127D01 is an irrelevant nanobody used as a negative control. BF, bright field.