IgA content of washed red blood cell concentrates

Saline-washed red blood cell (RBC) concentrates are largely depleted of leukocytes, microaggregates, and nearly of all plasma originally contained in the blood unit. Our aim was to determine the concentration of the eliminated IgA and total protein in the buffy coat and plasma removed RBC concentrate before and after a sequential dilution-centrifugation washing procedure. 75.3% protein, and 99% IgA were eliminated by the washing process used. The recovery of red blood cells was 87.2%. Our results have led to the conclusion that two sequential washings seem to guarantee an IgA level of less than 0.2 mg/unit to meet the recommendations of the Council of Europe. Additional advantages of washing include low levels of extracellular hemoglobin, metabolic waste products and debris in the supernatant.