Anticytomegalovirus T-cell clones

To the Editor: The article by Walter et al. (Oct. 19 issue)1 provides important evidence that the infusion of donor–derived CD8+ cytotoxic T-cell clones specific for human cytomegalovirus proteins can promptly reconstitute cellular immunity against human cytomegalovirus in recipients of allogeneic bone marrow, thus reducing the risk of morbidity and mortality related to viral infection. However, we would like to comment on two points. First, excretion of the virus in urine and its isolation from the throat have not been demonstrated to be predictive of cytomegalovirus disease in humans,2 and consequently these measures should not be used to monitor infection . . .