Serotec Worksheet 3

Direct Immunofluorescence Staining of Immunoglobulin Light Chains on B Lymphocytes in Whole Blood by Flow Cytometry

For use with Serotec's directly-conjugated dual colour reagents recognising human kappa and lambda immunoglobulin light chains.

The immunofluorescent staining of immunoglobulin expression by B lymphocytes in whole blood requires a procedure to remove serum immunoglobulins (which otherwise interfere and block staining with immunoglobulin-specific antibodies).

Note: This method provides a general procedure for use with the majority of Serotec reagents. In some cases specific recommendations are provided on product datasheets, and these methods should always be used in conjunction with product and batch specific information provided with each vial. Please note that a certain level of technical skill and immunological knowledge is required for the successful design and implementation of these techniques - these are guidelines only and may need to be adjusted for particular applications.

1. Collect blood into appropriate anti-coagulant - Serotec recommends the use of EDTA, although satisfactory results may also be obtained using heparin or acid-citrate dextrose.

2 Aliquot 2-3ml of whole blood into a 25ml universal container. Then add 20-25ml of PGB, pre-warmed to 37oC and mix well.

3. Centrifuge at 400g for 5 minutes. Carefully aspirate the supernatant taking care not to disturb the cell pellet, and resuspend the pellet in the residual supernatant.

4. Repeat steps 3 and 4 twice more (three washes in total).

5. Aliquot 100ml of the washed blood into the required number of test-tubes. Add appropriate volume of Serotec antibody at recommended dilution (see specific datasheet for details). Mix well and incubate at room temperature for 30 minutes.

6. Add 2ml of freshly prepared Serotec Erythrolyse (Cat. No. BUF04) and mix well. Incubate for 10 minutes at room temperature. Centrifuge at 400g for 5 minutes. Discard supernatant.

7. Wash with 2ml of PGB, centrifuge at 400g for 5 minutes. Discard supernatant.

8. Resuspend cells in 0.2ml of PGB or with 0.2ml of 0.5% paraformaldehyde in PBS if required.

9. Acquire data by Flow Cytometry.

Notes:

Appropriate control samples should always be included. We recommend the inclusion of an isotype-matched control in each case - please contact Serotec's Technical Services department for details of available reagents.

The cell washing procedure described above has no effect upon other cell surface antigens, and has been shown not to affect the recovery of individual cell subsets.

Solutions used:

PGB = Phosphate Buffered Saline pH 7.2-7.4 containing 20mM glucose and 1% Bovine Serum Albumin

Reference:

Reynolds, W.M. et al. (1992) A simple technique for the determination of k and l immunoglobulin light chain expression by B cells in whole blood. J. Imm. Meths. 151:123-129.

FOR RESEARCH USE ONLY. NOT FOR THERAPEUTIC OR DIAGNOSTIC USE