FIGURE 3.
Inhibition of chemokine receptor activation. A, inhibition of CXCR3 activation. Purified Nanobodies were incubated at the indicated concentrations with CXCL11 (5 nm). Subsequently, CXCR3-mediated PLC activation was determined in HEK293T cells co-expressing CXCR3 and Gαqi5. The Nanobodies inhibited CXCL11-induced signaling with the following pIC50 ± S.E. values: 11B1 (●), 7.9 ± 0.1 (n = 3); 11B7 (○), 7.7 ± 0.1 (n = 3). B, inhibition of CXCR4 activation. Purified 12A4 Nanobody was incubated at the indicated concentrations with CXCL12 (5 nm). Subsequently, CXCR4-mediated PLC activation was determined in HEK293T cells co-expressing CXCR4 and Gαqi5. Nanobody 12A4 inhibited CXCL12-induced signaling with a pIC50 ± S.E. value of 7.1 ± 0.1 (n = 5).