Second Donation of Bone Marrow; Japan Marrow Donor Program (JMDP) Experience.

In Japan, JMDP, founded in 1991, had collected and transplanted more than 5,000 bone marrows by the end of 2003. Meanwhile, total of 137 donors donated their bone marrow twice. The efficiency and the safety of those donations and the efficacy of those cells in the engraftment were evaluated retrospectively. In JMDP, volunteers aged from 20 to 50 are enrolled as the donor. A year after the first donation, the donors are allowed to donate their marrow again, if they wish. Marrow was collected from the posterior iliac crest under general anesthesia and, generally, different patients received the marrow from the single donor. Peripheral blood stem cell harvest is not permitted by the JMDP. Their mean age was 36.6 and 36 of them were female. The volume of the marrow and the nucleated cell number collected in the first and the second donation were 760 ± 290 vs 857 ± 230 ml (p=0.001) and 15.3 ± 6.8 vs 15.6 ± 6.9 x 10E9 cell (p=0.674), respectively. Cell concentration of bone marrow solution and nucleated cell number per recipient’s weight were significantly lower in the second donation (2.2 ± 0.8 vs 1.8 ± 0.7X 10E7 cell/ml (p=0.0004) and 3.3 ± 1.1 vs 2.8 ± 1.1 x 10E8 cell/kg (p<0.0001), respectively) revealing decreased cell dose. The efficacy of those cells was also evaluated comparing the available data from 127 pairs of the patients who received the marrow. Within these 254 recipients, data of 8 patients (2 in the first and 6 in the second donation) are missing and another 19 (8 and 11) were excluded because of early death before day 28. There was no difference between the first and the second donated marrow in the date of neutrophil recovery (p=0.5214) and platelet recovery (p=0.4108). There were two cases each of slow engraftment (up to day 35) and late rejection in 1 and 5 patients respectively (p=0.2132). The adverse effects of those donations were also compared. The incidence of fever more than 38 degrees, the duration of the febrile period and other adverse effects such as urinary pain, sore throat, infectious disease, liver dysfunction and pain on the wound lasting more than 7 days were compared and no significant difference was observed. In conclusion, second donation can be performed safely and the functions of those cells were as good as the ones donated first. However, because the cell dose of the second collection could be lower, it might be necessary to collect more marrow than the expected.