Nobukazu Watanabe

Influence of donor condition on postoperative graft survival and function in human liver transplantation.

BODY condition of a brain death patient, such as blood electrolytes and cardiovascular system, is often unstable because of lack of homeostasis, experience of hypoxia, and multiple severe body injuries. Therefore, postoperative hepatic allograft function should be associated with general condition of cadaveric organ donor. For this reason, several retrospective analyses of donor variables have attempted to identify risk factors predictive of both patient and graft survival after liver transplantation. In the present study, we investigated influence of donor condition, including age, need for vasopressor, and serum sodium concentration, on early postoperative graft outcome in human liver transplantation by means of prospective collection of donor and recipient data.

Allogeneic chimerism established with a mixture of low dose bone marrow cells and splenocytes in sublethally irradiated mice.

BACKGROUND Allogeneic chimerism has been established in graft-accepting recipients and the donor cells in the host may act in a major way to facilitate the induction of tolerance. In this study, we examined the effects of allogeneic chimerism after injecting donor bone marrow cells (BMCs) mixed with splenocytes (SPLCs) to the sublethally conditioned recipients. METHODS In BALB/c(H-2(d)) to B6(H-2(b)) combination, B6 recipients were irradiated at 7.5 Gy and were injected a mixture of donor BMCs and SPLCs intravenously. On day 90 after injection, the degree of chimerism in peripheral blood lymphocytes (PBL) and in the splenocytes was checked by flow cytometry. RESULTS In groups which were injected varying BMCs, when > 45 x 10(6) BMCs were injected into B6, a large percentage of donor cells were detected in PBL and in the spleen. In contrast, when < 30 x 10(6) BMCs were injected into B6, only a small percentage of donor cells were detected. In the groups which were injected 3 x 10(6) BMCs with varying SPLCs, when > 10 x 10(6) SPLCs were added, a large percentage of donor cells were detected in PBL and SPLCs, but a small percentage of donor cells were detected with the addition of < 3 x 10(6) SPLCs. A high percentage of chimeric mice showed donor specific tolerance in vitro, mixed lymphocyte responses, and in vivo, skin grafting. In contrast, only a small percentage of chimeric mice showed no donor specific tolerance by skin grafting. CONCLUSION These findings suggested that even a low dose of BMCs can establish a state of allogeneic chimerism and donor specific tolerance if combined with SPLCs.

Primary Low-grade Mucosa-associated Lymphoid Tissue (MALT) Lymphoma of the Ascending Colon.

上行結腸に発生した低悪性度MALTリンパ腫の1例を経験したので報告する. 症例は82歳の女性. 右腹部腫瘤を指摘され精査を施行, 上行結腸に隆起性腫瘍を認めた. 生検の結果はno malignancyであったが, 悪性リンパ腫も否定できず, また腫瘍により腸管内腔が狭窄を来すおそれがあるため, 結腸右半切除術を施行した. 病理診断にて上行結腸原発低悪性度MALTリンパ腫と診断した. 術後化学療法は施行しなかった. 消化管MALTリンパ腫のほとんどが胃原発である. 大腸, 特に上行結腸原発の低悪性度MALTリンパ腫の報告例はまれであり, 標準的な治療法は確立していない. MALTリンパ腫は予後良好であると言われているが, リンパ節転移の可能性もあるため, 手術は大腸癌に準じた治療が必要と考えられた.

New method to immortalize primary cultured rat hepatocytes

BACKGROUND In conventional methods of establishing hepatocyte cell lines, the immortalizing gene alone is introduced into hepatocytes. We designed a new method in which not only the immortalizing gene, the simian virus-40 large T-antigen (SV-40 Tag) gene, but also a drug-resistant gene, under the control of an albumin enhancer/promoter, were introduced into hepatocytes to efficiently obtain immortalized hepatocyte cell lines. METHODS The plasmid pAPUR contains the puromycin-resistant gene under the control of an albumin enhancer/promoter, and the pSVTag contains the early region of SV-40 enhancer/promoter and the SV-40 Tag gene. Both pAPUR and pSVTag were transferred into isolated rat hepatocytes by electroporation. After these cells were cultured on a collagen-coated dish for 24 hours, puromycin selection was started. Expression levels of albumin, alpha-fetoprotein (AFP), SV-40 Tag, and cytokeratin 19 (CK 19) in the transformed cells were evaluated by western analysis, immunocytochemical staining, and RT PCR. RESULTS Approximately 3 weeks after transfection, five or six colonies appeared on the dish. Twenty strains were obtained by cloning these cells. All strains that were similar to immature hepatocytes expressed albumin and SV-40 Tag, although CK 19 was not detected. AFP expression was detected in 33% of these strains. CONCLUSIONS All clones cotransfected by pAPUR and pSVTag expressed albumin. Our new method may be useful to establish hepatocyte cell lines.