Concanavalin A-FITC

Operating Instructions (The following is a recommended experimental protocol for guidance only, and adjustments are required based on your specific needs)
1. Stock Solution Preparation
1.1 Solvent: For most dyes, organic solvents are usually used for dissolution, such as anhydrous DMSO.
1.2 Concentration Recommendation: It is generally recommended to prepare a high-concentration stock solution of 1-10 mM.
2. Working Solution Preparation
2.1 Diluent: Phenol red-free RPMI 1640 medium is optional; alternatively, αMEM containing 10 mM HEPES (HY-D0857) buffer and 0.1% sodium azide can be used.
2.2 Working Concentration: 30 μg/mL; 25 μg/mL.
2.3 Notes: Adjust the working solution concentration as needed; prepare it freshly before use.
3. Staining Procedures
3.1 Protocol for Fibroblasts^[1]:
3.1.1 Sample Handling: Adherent cells can be directly stained in cell culture dishes, or stained as a suspension after trypsinization; suspension cells can be stained directly without specific centrifugation steps.
3.1.2 Incubation Conditions: Incubate with 25 μg/mL Concanavalin A-FITC at 4°C for 45 min.
3.1.3 Washing Step: No washing is required.
3.2 Protocol for Adherent Mouse Macrophages PU5-1.8^[2]:
3.2.1 Sample Handling: Use adherently cultured cells.
3.2.2 Incubation Conditions: Incubate with Concanavalin A-FITC working solution for 4 h under 5% CO₂ at 37°C.
3.2.3 Washing Step: Perform gentle washing after incubation.
3.3 Protocol for CHO Cell Lines (Adherent/Suspension)^[3]:
3.3.1 Sample Handling: Collect adherent cells via gentle trypsinization, then culture them in a spinner culture system for 18-20 hours before staining.
3.3.2 Incubation Conditions: Incubate with 30 μg/mL FITC-labeled Con A working solution at 4°C for 30 minutes.
3.3.3 Washing Step: No washing is required before detection.
4. Control Setup
4.1 Negative Control: Before treatment with Concanavalin A-FITC, treat cells with unlabeled Concanavalin A (HY-P2149) and methyl-α-D-mannopyranoside at 37°C for 15 min.
4.2 Hapten Sugar Inhibition Control: Add 0.2 M D-mannose (HY-N0379) to the incubation system to block the specific binding of Concanavalin A-FITC.
5. Detection and Analysis
5.1 Instrument Type: Flow cytometer; laser confocal scanning microscope.
5.2 Excitation/Emission Wavelengths: Wavelengths compatible with FITC; excitation at 488 nm with a ≥510 nm long-pass emission filter; a 530/30 nm emission filter is used for flow cytometry.
5.3 Result Analysis:
5.3.1 Fluorescence Intensity: Cells with low Concanavalin A-FITC binding show lower mean fluorescence intensity, while those with high binding show higher mean fluorescence intensity; Con A-resistant CHO cell lines exhibit lower fluorescence intensity than wild-type CHO cells, and revertants show fluorescence intensity between the two.
5.3.2 Fluorescence Localization: Initial staining is confined to the cell membrane; after incubation at 37°C for 3 hr, fluorescence localizes to perinuclear regions associated with the endoplasmic reticulum; in macrophages, fluorescence colocalizes with cytoplasmic mitochondrial signals that mainly accumulate at the cell periphery.
5.3.3 Fluorescence Color: Concanavalin A-FITC staining produces green fluorescence.