Percentage of positive skin tests after transplantation in recipients of bone marrow from atopic donors. Skin tests were categorized according to the results of pretransplantation skin testing in the donor and recipient. The results of skin tests that were positive in the donor and negative in the recipient (D+/R–) and negative in the donor and recipient (D–/R–) are shown. At the level of individual skin tests, there was initially a high rate of adoptive transfer of allergen-specific IgE from donor to recipient, followed by a high rate of acquisition of additional allergen-specific IgE for which the donor was negative prior to transplantation. Numbers in parentheses indicate the number of skin tests represented by each column.