[1] NETHERLANDS RED CROSS,BLOOD TRANSFUS SERV,CENT LAB,DEPT IMMUNOL HAEMATOL,POB 9406,1006 AK AMSTERDAM,NETHERLANDS
[2] UNIV AMSTERDAM,EXPTL & CLIN IMMUNOL LAB,AMSTERDAM,NETHERLANDS
[3] STATE UNIV GRONINGEN HOSP,DEPT CLIN IMMUNOL,9700 RB GRONINGEN,NETHERLANDS
[4] UNIV AMSTERDAM HOSP,ACAD MED CTR,DEPT HAEMATOL,AMSTERDAM,NETHERLANDS