IN-VIVO EX-VIVO T-CELL DEPLETION FOR GVHD PROPHYLAXIS INFLUENCES ONSET AND COURSE OF ACTIVE CYTOMEGALOVIRUS-INFECTION AND DISEASE AFTER BMT

Combined in vivo/ex who T cell depletion is effective in the prophylax is of graft-versus-host disease (GVHD) after allogeneic bone marrow tr ansplantation (BMT), but influences the occurrence of active cytomegal ovirus (CMV) infection and disease, Twenty nine patients receiving a T cell-depleted marrow graft (Campath-1M) after intravenous application of the monoclonal antibody Campath-1G prior to conditioning were moni tored for virus shedding and antigenaemia from day -7 to day +100, In seropositive patients in this group active CMV infection occurred more frequently (10 of 16) and much earlier (nine of 10 until day +21) tha n in 27 seropositive patients (10 of 27, P < 0.02) receiving cyclospor in A and methotrexate (CsA/MTX), Early active CMV infection after its vivo/ex vivo T cell depletion correlated strictly with an early increa se in blood lymphocyte counts (P < 0.01), with predominance of NK cell s and/or CD8(+) T cells, Three cases of very early interstitial pneumo nitis (LP) occurred after in vivo/ex vivo T cell depletion compared wi th none in the CsA/MTX group, IP was fatal in the only patient with ea rly active CMV infection, who remained lymphocytopenic till death on d ay +31, This may indicate that an early immune response against CMV is possible and essential for favourable clinical outcome.