PROTOCOL

1. Take 2ml of donor blood and 2ml of recipient blood, each into EDTA or citrate anticoagulant. Either submit to the laboratory for crossmatching or follow the protocol below.
1. Centrifuge for 5 minutes and harvest the plasma. Transfer 1 drop of concentrated cells to 3ml of isotonic saline and resuspend.
1. Wash the cells in each sample 3 x in isotonic saline. Finally resuspend the cells in 3ml isotonic saline giving approximately a 5-10% suspension.
1. Into two tubes (or microtitre wells) mix:
2. Tube 1 : Donor cells (in isotonic saline) and recipient plasma in equal volumes 

(e.g. 2 drops of each).
3. Tube 2 : Recipient cells (in isotonic saline) and donor plasma in equal volumes 

(e.g. 2 drops of each).
1. Incubate at 37° C for 1 hour.
1. Put one drop of fluid from each tube onto a microscope slide and observe microscopically for agglutination
2. Positive for agglutination = a mismatch and a different donor should be sought.