Kentaro Tsunamoto

Chimerism analysis on mononuclear cells in the CSF after allogeneic bone marrow transplantation.

To evaluate the chimeric status of mononuclear cells in the CSF after allogeneic BMT, cells were analyzed by FISH using satellite DNA probes for human X and Y chromosomes. CSF cells were obtained from five pediatric ALL patients who received BMT from sex- mismatched donors. All patients received TBI-containing conditioning regimens. We found that CSF cells showed complete donor type in 19–97 days after BMT, when complete donor type hematopoiesis was observed. The rapid entry of the donor leukocytes into the brain may exert beneficial effects to eradicate the residual CNS leukemic cells and prevent a CNS relapse in ALL patients after BMT.

Donor lymphocyte infusion at unstable mixed chimerism in an allogeneic BMT recipient for chronic granulomatous disease

We report a 14-year-old boy who had successfully received allogeneic BMT for chronic granulomatous disease and 3 years later was treated with donor lymphocyte infusion (DLI, 3.3 × 108 cells/kg) at unstable mixed chimerism in association with reduced neutrophil function. Following DLI, the patient developed transient acute hepatic GVHD, which was confirmed by liver biopsy and was manageable with cyclosporin A and prednisolone. The patient eventually attained complete chimerism with improved neutrophil function. At the time of writing (2.5 years from the DLI), the patient is doing well, free from infectious episodes and chronic GVHD. Our experience suggests that DLI could be a safe and effective strategy for dissolution of unstable mixed chimerism in BMT recipients for inherited disorders.

Procoagulant Activity of Human Neuroblastoma Cell Lines, in Relation to Cell Growth, Differentiation and Cytogenetic Abnormalities

Procoagulant activity (PCA) was investigated in relation to cell growth, differentiation, and cytogenetics in seven human neuroblastoma cell lines. Before 5‐bromodeoxyuridine (BrdUrd) treatment, PCA was notably heterogeneous, with the highest activity in NCG (S‐type in morphology) 40‐to 100‐fold greater than the lowest activity in SK‐N‐D2 (N‐type). PCA was not related to 1p abnormalities. After BrdUrd treatment at 5 μg/ml for 6 days, PCA increased 6.8‐fold in GOTO and 2.7‐fold in SK‐N‐DZ with associated growth inhibition and morphological changes (I‐type morphology converted to S‐type in GOTO and N‐type converted to an advanced N‐type in SK‐N‐DZ). In contrast, only growth suppression was observed in 2 other cell lines, and no changes in PCA, growth or morphology were induced in the remaining 3 cell lines.

Numerous nonclonal chromosomal aberrations arising in residual recipient hematopoietic cells following allogeneic bone marrow transplantation

Summary:A young female patient in a second remission of acute lymphoblastic leukemia underwent bone marrow transplantation after total body irradiation and high-dose cytarabine from her HLA-matched brother. Following successful engraftment, mixed chimerism was seen 75 days post transplant. The karyotype contained numerous abnormalities in residual recipient cells. Chromosomes 1, 7, 13, and X were significantly more affected than other chromosomes. The high-frequency breakpoints identified were 1p22.2, 5q31.2, and 13q14.2. Some karyotypes specific for leukemia, such as t(9;22)(q34.1;q11.2) and t(8;21)(q22.2;q22.2), not seen with the original disease, were also present. As the frequency of aberrant chromosomes increased markedly with time, donor leukocytes were infused 14 months after BMT, which effectively eradicated the abnormal karyotypes.

Urinary 6-keto-PGF1α level in patients with childhood leukemia/lymphoma; A possible indicator of vascular damage

To determine the effect of anti-neoplastic chemotherapy on the vascular system(s) of children with leukemia/lymphoma, urinary excretion of 6-keto-PGF1 alpha was measured by radioimmunoassay (RIA). In 4 patients receiving therapy, 6-keto-PGF1 alpha increased to a mean of 148 (range; 126-170)% during therapy, then returned to pre-treatment level 3-5 days later. In 18 long-term survivors who had completed therapy, 6-keto-PGF1 alpha was determined to be a mean of 275 (range; 52-905) ng/g creatinine, and in the healthy control children the mean was 146 (range; 71-348) ng/g creatinine. These results were contrary to our hypothesis that chemotherapy might cause a decreased synthesis of PGI2, a precursor of 6-keto-PGF1 alpha, and suggest that increased urinary 6-keto-PGF1 alpha reflects a vascular response to acute exposure to chemotherapeutic drugs and possible vascular damage due to long-term intensive chemotherapy in pediatric patients with leukemia/lymphoma.