Novel Non-isotopic Method for the Localization of Receptors in Tissue Sections

• Published in: The journal of histochemistry and cytochemistry Vol. 49; no. 12; pp. 1509 - 1517
• Main Authors: Desnoyers, Luc, Simonette, Rebecca A, Vandlen, Richard L, Fendly, Brian M
• Format: Journal Article
• Language: English
• Published: Los Angeles, CA Histochemical Soc 01-12-2001; SAGE Publications
• Subjects: Animals; Fetus; Fluorescent Antibody Technique; Frozen Sections; Histidine - genetics; Humans; Image Processing, Computer-Assisted; Insulin-Like Growth Factor I - genetics; Kidney - metabolism; Ligands; Organ Specificity; Rats; Receptor, IGF Type 1 - metabolism; Recombinant Fusion Proteins - genetics; Recombinant Fusion Proteins - metabolism; insulin-like growth factor-1; receptor; insulin-like growth factor receptor-1; ligand binding; immunofluorescence
• ISSN: 0022-1554; 1551-5044
• DOI: 10.1177/002215540104901204

We describe a novel fluorescent method for the detection of receptors for chimeric proteins in tissue sections. The technique was developed using a recombinant human insulin-like growth factor (IGF-1) chimera, bearing six additional histidine residues at the carboxy-terminal end (IGF-1-His). We demonstrated that dehydration of the tissue sections was detrimental for binding and that its prevention dramatically increased sensitivity. The specificity of IGF-1-His interaction was shown by gradual abolition of the fluorescent signal in the presence of increasing concentrations of IGF-1. Combining immunofluorescence with in situ ligand binding, we showed that IGF-1-His binding corresponded to the IGF-1 receptor (IGFR-1) distribution in human fetal kidney. Moreover, incubation of the tissue sections with an anti-IGFR-1 blocking antibody abolished IGF-1-His binding, demonstrating that the interaction was mediated by the IGFR-1. The method was also used to localize the IGFR-1 in E18 rat embryo sagittal sections. The IGF-1-His binding pattern was observed in brain, cartilage, lung, skin, heart, diaphragm, and tongue, and paralleled the previously reported IGFR-1 distribution. We believe that this new non-isotopic in situ ligand binding method will facilitate rapid and accurate localization of receptors in tissue sections.