title: Con A conjugated to Europium(III) cryptate as a new histological tool for prostate cancer investigation using confocal microscopy.
abstract: Lectins are carbohydrate recognition proteins that can be used as probes to reveal the glycosylation state of cells. They frequently have been used for diagnostic and prognostic cancer studies. For fluorescence based analysis, lectins commonly are conjugated to fluorescein isothiocyanate (Con A-FITC); however, this molecule loses its fluorescence quickly. We conjugated Europium cryptate to Con A (Con A-cryp-Eu) for use as a histochemical luminescent probe to recognize glucose/mannose residues in benign prostatic hyperplasia and prostatic carcinoma tissues, and used confocal microscopy instead of commercial Con A-FITC. Tissues were treated with Evans blue to suppress intrinsic tissue fluorescence before incubation with Con A-cryp-Eu or Con A-FITC. Con A-cryp-Eu exhibited hemagglutinating activity. Con A-cryp-Eu showed the same binding pattern as Con A-FITC in prostate stroma and gland cells. Staining was strong in benign prostate hyperplasia and prostate carcinoma tissues. Con A-cryp-Eu probe stained glucose/mannose residues in prostatic carcinoma more intensely than Con A-FITC. Furthermore, staining with Con A-cryp-Eu showed greater fluorescence intensity than Con A-FITC and the emission of Con A-cryp-Eu was more stable than the Con A-FITC for seven days under the same storage conditions. Maintenance of the luminescent properties and the binding pattern of Con A-cryp-Eu favor its use as an auxiliary histochemistry probe for prostatic tissue studies.
authors.affiliation: Keizo Asami Immunopathology Laboratory, University Federal of Pernambuco.
authors.forename: M J B M
authors.initials: MJ
authors.lastname: Rêgo
authors.forename: L P B G
authors.initials: LP
authors.lastname: Silva
authors.forename: J K G
authors.initials: JK
authors.lastname: Medeiros
authors.forename: R C B Q
authors.initials: RC
authors.lastname: Figueiredo
authors.forename: S
authors.initials: S
authors.lastname: Alves-Júnior
authors.forename: E I C
authors.initials: EI
authors.lastname: Beltrão
mesh_terms: D003208:Concanavalin A / Q000737:chemistry*; D006801:Humans; D049408:Luminescent Agents / Q000737:chemistry*; D008297:Male; D018613:Microscopy, Confocal; D009942:Organometallic Compounds / Q000737:chemistry*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D012680:Sensitivity and Specificity
chemical_list: D049408:Luminescent Agents; D009942:Organometallic Compounds; D003208:Concanavalin A; C070734:europium(III) trisbipyridine cryptate
keywords: Con A-Europium; confocal microscopy; cryptate; histochemistry; lectin