MojoSort™ Mouse CD11c Nanobeads Column Protocol

 

Introduction

BioLegend MojoSort™ nanobeads work in commonly used separation columns, based on our internal research as well as validation by external testing by academic labs. This simple protocol consists of following the MojoSort™ protocol to label the cells with pre-diluted MojoSort™ reagents and using the columns as indicated by the manufacturer.

Note: Due to the properties of our beads, it may be possible to use far fewer beads than with other commercial suppliers. We recommend a titration to find the best dilution factor. However, as a general rule, dilutions ranging from 1:3 to 1:20 for the Nanobeads can be used. Please contact BioLegend Technical Service (tech@biolegend.com) if further assistance is needed.

 

Important Note

MojoSort™ magnetic particles can be used with other commercially available magnetic separators, both free standing magnets and column-based systems. Because MojoSort™ protocols are optimized for the MojoSort™ separator, the protocols may need to be adjusted for other systems. Please contact BioLegend Technical Service (tech@biolegend.com) for more information and guidance. We do not recommend using MojoSort™ particles for BD’s IMag™ or Life Technologies’ DynaMag™.

Sample Preparation: Enzymatic digestion of mouse spleen is recommended to achieve the highest purity and yield of CD11c+ cells. There are several protocols published that can be applied. As a general guideline, cut mouse spleen into pieces and incubate in 0.5 mg/ml Collagenase for 30 to 60 minutes at room temperature or 37°C. Place the tube in a rocking platform with continuous agitation or gently pipette every 10 minutes. Alternatively, inject 1 ml of enzymes solution in the uncut organ. Force the tissue through a 70 µm filter to prepare a single cell suspension, and wash with complete media. Resuspend cells in 0.1 mg/ml DNase 1 solution and incubate at room temperature for 10 minutes. Again, filter cells through a 70 µm filter and wash with complete media. Resuspend in complete media or MojoSort™ Buffer and keep on ice until ready to use.

 

Protocol Steps


  1. Prepare cells from your tissue of interest or blood without lysing erythrocytes.  

  2. In the final wash of your sample preparation, resuspend the cells in MojoSort™ Buffer by adding up to 4 mL in a 5 mL (12 x 75 mm) polypropylene tube.
    Note: Keep MojoSort™ Buffer on ice throughout the procedure.  

  3. Filter the cells with a 70 µm cell strainer, centrifuge at 300xg for 5 minutes, and resuspend in a small volume of MojoSort™ Buffer. Count and adjust the cell concentration to 1 x 108 cells/mL by adding MojoSort™ Buffer.

  4. Aliquot 100 µL (107 cells) into a new tube. Add 10 µL of TruStain FcX (anti-mouse CD16/32 antibody), mix well and incubate at room temperature for 10 minutes. Scale up the volume accordingly if separating more cells. For example, if the volume of Human TruStain FcX™ for 1x107cells is 10 µL, add 100 µL for 1 x 108 cells. When working with less than 107 cells, use indicated volumes for 107cells.  

  5. Resuspend the beads by vortexing, maximum speed, 5 touches. Add 10 µL of Antibody Nanobeads. Mix well and incubate on ice for 15 minutes. Scale up the volume accordingly if separating more cells.

  6. Wash the cells by adding MojoSort™ Buffer up to 4 mL. Centrifuge the cells at 300xg for 5 minutes.

  7. Discard the supernatant.  

  8. Resuspend cells in the appropriate amount of MojoSort™ Buffer and proceed to separation. At least 500 µL is needed for column separation.
    Note: There are several types of commercially available columns, depending on your application. Choose the one that fits best your experiment:  

 

Columns:

 

 

Example of magnetic separation with medium capacity columns:

  1. Place the column in a magnetic separator that fits the column.
  2. Rinse the column with 3 mL of cell separation buffer.
  3. Add the labeled cell suspension to the column through a 30 µm filter and collect the fraction containing the unlabeled cells.
  4. Wash the cells in the column 3 times with 3 mL of buffer and collect the fraction containing the unlabeled cells. Combine with the collected fraction from step 3. These cells may be useful as controls, to monitor purity/yield, or other purposes.
  5. Take away the column from the magnet and place it on a tube. Then add 5 mL of buffer and flush out the magnetically labeled fraction with a plunger or supplied device. These are the positively isolated cells of interest; do not discard. To increase the purity of the magnetically labeled fraction repeat the isolation process with a new, freshly prepared column.

 

Data

 

Flow cytometry. High purity and yield. “After Isolation” plot shows purified population of interest using pre-diluted MojoSort™ reagents in separation columns.

 

 

Kit Purity Yield
Mouse CD19 Nanobeads 97.7% 94%

 

 

Electron Microscopy. MojoSort™ Nanobead-isolated CD19+ cells using columns do not display more bound beads on the cell surface (A) as compared to cells isolated with a compatible commercial product using the same columns (B). Red arrows indicate where the particles are located. Numbers indicate either 2 or 3 magnetic particles adjacent to each other. Pictures were taken at the same magnification, scale shown in B. Images are representative of 41 different cells each.


B cells isolated with MojoSort™ CD19 nanobeads using separation columns.

B cells isolated with competitor's CD19 magnetic beads using separation columns.