Figure 1.

Chemokine binding activity in tick saliva. (a) Tick saliva inhibits the binding of CCL3, CCL5, and CXCL8 to their cognate receptors. Radiolabeled chemokines were incubated with CHO cell membranes expressing CCR1 for CCL3 and CCL5, and CXCR2 for CXCL8, in the presence of 1 μl, 10 μl, or in the absence of tick saliva. The antichemokine activity is caused by the presence of more than one binding protein because an excess of CXCL8 did not abolish the inhibition of CCL3 binding. Error bars represent the mean ± SEM. (b) Detection of CHPBs in tick saliva by SPR. Sensograms demonstrated binding to CCL5(E66A) and CCL3 immobilized on a CM4 chip. (c) Detection of distinct CHPBs to CCL5 and CXCL8 by Retentate chromatography SELDI of flight mass spectrometry (RC-SELDI-TOF-MS). Tick saliva was incubated on a PS-20 Proteinchip array coated with either CCL5 (bottom), CXCL8 (middle), or the control protein equine myoglobin (top). Specific peaks, indicated by arrows, corresponding to a protein with a mass of 11,052 Daltons binding to CCL5 and of 7,133 Daltons for the binding to CXCL8 were observed.