Comparative sequence analysis and trypsinization of Amblyomma americanum and human IGFBP-rP1: A. Alignment of A. americanum and human IGFBP-rP1 amino acid sequences in the region where human protein is cleaved by trypsin. B. Products of 15 min trypsin digestion of rAamIGFBP-rP1 and its human homologue performed at 37°C, separated on 12.5% SDS-PAGE and stained with Coomassie brilliant blue. C) Western blot detection of products of rAamIGFBP-rP1 trypsinization using antibody to 48h fed A. americanum female tick saliva proteins. D) Western blot detection of products of rAamIGFBP-rP1 trypsinization using an antibody to hexa-histidine tag. Lane M – marker, lane R – non digested rAamIGFBP-rP1, lane R+T – rAamIGFBP-rP1 digested with trypsin, lane H – non digested human IGFBP-rP1, lane H+T – human IGFBP-rP1 digested with trypsin, and lane T – control containing trypsin only.