A multicenter comparative study was carried out to investigate the efficacy and safety of hematopoietic stem cell transplantation with conditioning regimens containing melphalan in pediatric patients with acute lymphoblastic leukemia. One hundred twenty three patients at a variety of remission stages were eligible for study participation. Eighty-nine were transplanted with allogeneic grafts and 34 patients with autologous grafts (23 cases with bone marrow and 11 cases with peripheral blood stem cells). Conditioning regimens used were as follows: (A) melphalan and busulfan for 40 patients, (B) melphalan, busulfan and TBI for 44 patients, (C) other regimens for 39 patients. To accelerate engraftment G-CSF (lenograstim) was administered as a 1-hour or 24-hour drip infusion daily at 5 micrograms/kg from day 5 until hematological recovery. The five year disease free survival (DFS) was 63% for 42 patients at CR 1, 41% for 41 patients at CR 2 and 33% for 40 patients at other stages. There was no significant difference in the DFS between allogeneic-transplantation and autologous-transplantation in all disease stages. In patients at remission stage for CR 1 and CR 2, the 5-year DFS by conditioning regimen was 63% for regimen (A), 54% for regimen (B) and 54% for regimens with melphalan and TBI. There was no significant difference in the DFS between the groups. Serious complications such as renal failure were observed in 11%, veno-occlusive disease in 9%, and interstitial pneumonia in 9%. The most dominating cause of death was relapse in the disease (48% of deaths) which was most commonly observed in autologous transplantation. Contrary to that, treatment related toxic death was the most frequent cause of deaths in allogeneic-transplantation.

A 29-year-old male was diagnosed as having non-Hodgkin's lymphoma (NHL, diffuse, large cell, B-cell, stage IV) in June 1999. He underwent 7 courses of chemotherapy and double autologous peripheral stem cell transplantation (total dose: CPA 13,000 mg, BUS 892 mg, L-PAM 150 mg, MCNU 870 mg, MTX 60 mg, Ara-C 160 mg, DXR 350 mg, VP-16 11,190 mg, VCR 8 mg, CBDCA 700 mg, and MIT 22 mg) for NHL and obtained complete remission in April 2000. In September 2000, he suffered from progressive general malaise. Laboratory findings showed marked leukocytosis with 85% leukemia cells, which were positive for alpha-naphthyl butyrate esterase. Surface-marker analysis of the leukemia cells showed positive results for CD11b, CD11c, CD13, CD15, CD33, CD56, CD64, CD65, CD71 and HLA-DR, and chromosomal analysis revealed add(8) (p11), add(9) (p13). He was diagnosed as having AML (M5a) and was still in complete remission for NHL. He did not respond to chemotherapy and died in December 2000, believed to be from therapy-related leukemia induced by the VP-16 used for treating NHL, judging by the patient's short clinical course and monocytic type of leukemia.

We observed massive hemolysis after allogeneic peripheral blood stem cell transplantation with minor ABO incompatibility (the donor was group O and the recipient group A). The patient was a 21-year-old man diagnosed as having Philadelphia chromosome-positive chronic myelogenous leukemia. On day 7 post-transplant, there was abrupt onset of massive hemolysis necessitating supportive treatment with transfusions. During the allogeneic peripheral blood stem cell transplantation the patient had received 2 x 10(8) CD3 positive cells/kg and 7.8 x 10(7) CD19 positive cells/kg donor lymphocytes with stem cells. The present case shows that in allogeneic peripheral blood stem cell transplantation with ABO incompatibility, severe hemolysis occurs early after transplantation presumably due to the transfusion of a large number of lymphocytes.

There are accumulating evidence of immunological therapeutic effect induced by reduced-intensity allogeneic hematopoietic stem cell transplantation (mini-transplantation) for solid malignancies. The reduced toxicity of a mild preconditioning regimen in mini-transplantation has facilitated its application to patients with various solid tumors. The so-called graft-versus-tumor (GVT) effect usually appears when graft-versus-host disease develops. Therefore, it is suggested that the fundamental mechanism of the GVT effect is a reaction by T-lymphocytes against various tumor-associated alloantigens of the tumor cells. Although mini-transplantation appears effective in some patients with renal cell carcinoma or breast cancer, it is still unclear whether the therapeutic mechanism could work on other solid tumors. Well-designed prospective clinical trials are warranted in order to determine the role of mini-transplant in the therapeutic strategy for solid tumors.

Hohara and Kozagawa in the Kii peninsula of Japan are reported to be high-incidence foci of amyotrophic lateral sclerosis (Kii ALS) and parkinsonism-dementia complex (Kii PDC). During the period between 1996 and 1999, three Kii ALS patients and 19 Kii PDC patients were confirmed neurologically in Hohara among which, one Kii ALS patient and two Kii PDC patients were examined neuropathologically. The ratio of positive family history where ALS or PDC occurred within the fourth degree of the relatives was 33.3% in the patients with Kii ALS, 78.9% in those with Kii PDC, and 72.7% in total. The ages of onset were between 57 years and 63 years (mean age: 60.0 years) in the patients with Kii ALS and between 53 years and 74 years (mean age: 66.5 years) in those with Kii PDC. All of the Kii ALS patients were female, and the male to female ratio of the Kii PDC patients was 1:1.7. The clinical features of Kii ALS were basically similar to those of classical ALS. The core clinical features of Kii PDC consisted of dementia and parkinsonism, frequently accompanied by motor neuron symptoms. The cardinal neuropathological features of Kii ALS/PDC included many neurofibrillary tangles (NFTs) associated with loss of nerve cells in the cerebral cortex and the brain stem, as well as morphological alterations diagnostic of ALS. Ultrastructurally, NFTs consisted of paired helical filaments. When we compared the clinical features of these Kii ALS patients with those that had been surveyed in 1969, the male to female ratio changed from male dominance to female dominance and the mean age of the onset of the disease was delayed by approximately 10 years. The most frequent initial symptom had been weakness of the lower limbs in the survey in 1969 and was bulbar palsy in this study. As to Kii PDC, this is the first report of the clinical features of many cases.

Regenerative medicine and artificial organs are fields of development in the 21st century. Various stem cells are found in many organs, and it is expected that medical treatment with the induction of regeneration in vivo and ex vivo using growth factors will be available. On the other hand, human embryonic stem cell lines (ES cells), which can transform themselves into any cell in the body, have been established. Since the development of cloning technology, the production of "individual ES cells" is also no longer only a dream. At the same time, the use of human cloned embryos entails important ethical and social considerations. As is well known, although artificial organs are not perfect, they can substitute for the functions of the kidney and heart. In the future, miniaturization and advanced features can be expected by application of microtechnologies. To execute various functions of synthesis and metabolic processes, for example, with an artificial liver, hybrid artificial organs incorporating cell functions are in development. We should not use animal cells because of unknown infectious diseases. It is therefore desirable to use human cells by the application of regenerative medicine or genetic engineering. Because both regenerative medicine and artificial organs can be expected to change medical treatment dramatically in the 21st century, steady efforts to clarify cell functions and molecular mechanisms will be required, as well as addressing ethical/social considerations.

Demand on the use of human materials and personal disease information for research and development comes on the stage of action. International competition in biomedical and pharmaceutical research pushed the government and related societies about to release guidelines on the issue to ensure the protection of direct and indirect research participants. To work on human materials and information now requires ethical and scientific review by the research ethical committee and the guidelines set the stage of reviewing process. We should aware of the overall view of situation around and of the guidelines before planning the experiments and analyses on human materials and personal information. In this review we summarized the related guidelines and put comments on them to help researchers to understand the situation.