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1.
Zentralbl Chir ; 141(3): 253-5, 2016 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-27331287

RESUMO

Hemihepatectomy continues to be a standard procedure for the resection of primary or secondary liver tumours in hepatobiliary surgery. In this tutorial, a case study illustrates the indication for liver resection as well as surgical steps and different techniques. Indications for right or left hemihepatectomy include liver tumours that cause a diffuse or extended infiltration of one half of the liver or tumours extending to the central confluence of liver veins or the liver hilum. Usually, a resection limit is only required in the case of extended hemihepatectomies, where a two-stage resection is needed. In addition to exploration and intraoperative ultrasound, this tutorial presents different entry sites, liver mobilisation, hilum preparation and common techniques of parenchymal dissection. Finally, a number of haemostasis, closure and biliary monitoring techniques are shown. The video tutorial demonstrates all fundamental steps of hemihepatectomy from indication to closure, with a special focus on different approaches.


Assuntos
Neoplasias Colorretais/cirurgia , Hepatectomia/métodos , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Fístula Biliar/prevenção & controle , Quimioterapia Adjuvante , Neoplasias Colorretais/patologia , Terapia Combinada , Hemostasia Cirúrgica/métodos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Terapia Neoadjuvante , Complicações Pós-Operatórias/prevenção & controle , Técnicas de Sutura
2.
BMC Surg ; 15: 93, 2015 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-26226942

RESUMO

BACKGROUND: Solitary metastases to the pancreas are rare. Therefore the value of resection in curative intention remains unclear. In the literature there are several promising reports about resection of solitary metastasis to the pancreas mainly of renal origin. CASE PRESENTATION: Here we report for the first time on the surgical therapy of a 1.5 cm solitary pancreatic metastasis of an adrenocortical carcinoma. The metastasis occurred almost 6 years after resection of the primary tumor. A partial pancreatoduodenectomy was performed and postoperatively adjuvant mitotane treatment was initiated. During the follow-up of 3 years after surgery no evidence of tumor recurrence occurred. CONCLUSION: Resection of pancreatic tumors should be considered, even if the mass is suspicious for metastatic disease including recurrence of adrenocortical cancer.


Assuntos
Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/secundário , Carcinoma Adrenocortical/cirurgia , Recidiva Local de Neoplasia/patologia , Neoplasias Pancreáticas/secundário , Neoplasias Pancreáticas/cirurgia , Antineoplásicos Hormonais/uso terapêutico , Quimioterapia Adjuvante , Feminino , Humanos , Pessoa de Meia-Idade , Mitotano/uso terapêutico , Pâncreas/cirurgia , Pancreaticoduodenectomia
3.
Ann Oncol ; 25(5): 1018-25, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24585720

RESUMO

BACKGROUND: Initially, unresectable colorectal liver metastases can be resected after response to chemotherapy. While cetuximab has been shown to increase response and resection rates, the survival outcome for this conversion strategy needs further evaluation. PATIENTS AND METHODS: Patients with technically unresectable and/or ≥5 liver metastases were treated with FOLFOX/cetuximab (arm A) or FOLFIRI/cetuximab (arm B) and evaluated with regard to resectability every 2 months. Tumour response and secondary resection data have been reported previously. A final analysis of overall survival (OS) and progression-free survival (PFS) was carried out in December 2012. RESULTS: Between December 2004 and March 2008, 56 patients were randomised to arm A, 55 to arm B. The median OS was 35.7 [95% confidence interval (CI) 27.2-44.2] months [arm A: 35.8 (95% CI 28.1-43.6), arm B: 29.0 (95% CI 16.0-41.9) months, HR 1.03 (95% CI 0.66-1.61), P = 0.9]. The median PFS was 10.8 (95% CI 9.3-12.2) months [arm A: 11.2 (95% CI 7.2-15.3), arm B: 10.5 (95% CI 8.9-12.2) months, HR 1.18 (95% CI 0.79-1.74), P = 0.4]. Patients who underwent R0 resection (n = 36) achieved a better median OS [53.9 (95% CI 35.9-71.9) months] than those who did not [21.9 (95% CI 17.1-26.7) months, P < 0.001]. The median disease-free survival for R0 resected patients was 9.9 (95% CI 5.8-14.0) months, and the 5-year OS rate was 46.2% (95% CI 29.5% to 62.9%). CONCLUSIONS: This study confirms a favourable long-term survival for patients with initially sub-optimal or unresectable colorectal liver metastases who respond to conversion therapy and undergo secondary resection. Both FOLFOX/FOLFIRI plus cetuximab, appear to be appropriate regimens for 'conversion' treatment in patients with K-RAS codon 12/13/61 wild-type tumours. Thus, liver surgery can be considered curative or alternatively as an additional 'line of therapy' in those patients who are not cured. CLINICAL TRIAL NUMBER: NCT00153998, www.clinicaltrials.gov.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Camptotecina/uso terapêutico , Cetuximab , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Fluoruracila/uso terapêutico , Humanos , Estimativa de Kaplan-Meier , Leucovorina/uso terapêutico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Compostos Organoplatínicos/uso terapêutico , Modelos de Riscos Proporcionais , Resultado do Tratamento
4.
Transplant Proc ; 40(9): 3179-81, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19010226

RESUMO

BACKGROUND: The purpose of this study was to provide information concerning the performance of selective transarterial chemoembolization (TACE) as a palliative treatment in patients with hepatocellular carcinoma (HCC), also in the case of multifocal lesions. PATIENTS AND METHODS: We reviewed prospectively collected data on 43 patients with cirrhosis and HCC who underwent selective TACE as a palliative treatment. Patients were assigned to one of two groups: (1) those with one to three HCC lesions, and (2) those with four or more HCC lesions. RESULTS: One hundred and two TACE sessions were applied in 43 patients. There were 39 men and 4 women with a mean age of 65.5 +/- 8.273 years. Alpha fetoprotein levels were elevated to a median value of 73.8 U/mL prior to first TACE (range, 1.5-25615 U/mL). Fourteen patients underwent one session, and 29 patients from two to eight TACE sessions. Bilobar HCC distribution prior to initial TACE was evident in 40% of the patients. Solitary HCC was radiologically diagnosed in 14 patients. Twenty-seven patients were assigned to group 1 and 16 patients to group 2. No significant differences were found between the two groups concerning the number of TACE sessions and the severity of liver cirrhosis. Currently 12 patients are alive after a median follow-up of 25 months (range, 3-84 months). Three- and 5-year survival rates according to patient groups were 45% and 19%, and 42% and 11% for the patients' groups 1 and 2, respectively (P = .87). CONCLUSIONS: HCC patients without a curative therapy option may benefit from palliative TACE, also in the case of multifocal lesions.


Assuntos
Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/terapia , Idoso , Angiografia , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Cuidados Paliativos , Estudos Retrospectivos , Análise de Sobrevida , Tomografia Computadorizada por Raios X , alfa-Fetoproteínas/análise
5.
Transplantation ; 69(6): 1058-67, 2000 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-10762208

RESUMO

BACKGROUND: Our purpose was to develop and evaluate protocols for selective immunosuppression after liver transplantation using the monoclonal antibodies (mAbs) NDS-61, directed against the interleukin-2 receptor (CD25), and 1A29, directed against the intercellular adhesion molecule-1 (CD54), in combination with subtherapeutic cyclosporine (CsA). METHODS: Orthotopic rat liver transplantation (ORLT) was performed in a DA-to-LEW strain combination. Immunosuppression was administered from day 0 to +13. Functional parameters such as survival time, body weight, and serum bilirubin levels were measured and the liver grafts were evaluated histologically. RESULTS: A stepwise tapering of CsA from 3 to 0.25 mg/kg/day reduced the long-term survival rate. All animals died at a CsA dosage of 0.25 mg/kg/day, which was therefore defined as subtherapeutic. Monotherapy with the anti-CD25 mAb was performed at dosages of 600 and 1800 microg/kg/day. The lower mAb dosage resulted in a long-term survival rate of 12% and was defined as subtherapeutic. The combination therapy of CsA (0.25 mg/kg/day) and anti-CD25 mAb (600 microg/kg/day) produced a synergistic effect and led to a long-term survival rate of 84%. This survival rate was significantly higher than those after either CsA (P<0.005) or anti-CD25 mAb (P<0.001) monotherapy. Both dosages (10 and 30 microg/kg/day) of anti-CD54 mAb monotherapy as well as anti-CD54 mAb combined with a subtherapeutic dosage of CsA were ineffective in preventing acute allograft rejection. The addition of anti-CD54 mAb (30 microg/kg/day) to combined CsA plus anti-CD25 mAb therapy (triple therapy), however, increased the long-term survival rate to 100%. In the triple therapy group there was no rejection process in the liver allografts at any time, and donor-specific tolerance could be shown by donor-specific and third-party heterotopic heart transplantation. CONCLUSIONS: The synergistic action of subtherapeutic CsA plus anti-CD25 mAb NDS-60 could be demonstrated, whereas anti-CD54 mAb only had a positive effect in a triple therapy group. Triple therapy prevented both acute and chronic rejection and induced donor-specific tolerance.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Ciclosporina/uso terapêutico , Tolerância Imunológica/efeitos dos fármacos , Imunossupressores/uso terapêutico , Molécula 1 de Adesão Intercelular/imunologia , Transplante de Fígado/imunologia , Receptores de Interleucina-2/imunologia , Animais , Sinergismo Farmacológico , Quimioterapia Combinada , Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Imuno-Histoquímica , Fígado/química , Masculino , Modelos Biológicos , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Ratos Endogâmicos , Reoperação , Fatores de Tempo , Transplante Homólogo , Transplante Isogênico
6.
Transplantation ; 71(12): 1848-52, 2001 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-11455268

RESUMO

BACKGROUND: Drug-induced tolerance of rat liver allografts is well documented. We analyzed cellular events during immunosuppressive therapy on day (d) 10 and in the late phase (d 100) after transplantation to assess for characteristics in the intrahepatic leukocyte (IHL) population in the phase of tolerance. METHODS: Lewis rats served as recipients of Dark Agouti rat livers. Temporary immunosuppression with either cyclosporine (CsA) monotherapy (3 mg/kg/d) or triple therapy that consisted of a subtherapeutic CsA dosage (0.25 mg/kg/d) and monoclonal antibodies directed against the interleukin-2 receptor (IL-2R, CD25) and the intercellular adhesion molecule-1 (ICAM-1, CD54) was administered from postoperative d 0 to d 13. Cell migration and cell activation within liver grafts was assessed by standard histology and flow cytometry. IHL apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL). RESULTS: Both CsA monotherapy and triple therapy prolonged liver allograft survival to more than 100 d and led to the induction of donor-specific tolerance. Untreated recipients rejected their allografts within 14 d. In both groups, donor-specific IHLs initially dropped to 18% to 25% on d 10, but they rebounded to as much as 40% on d 100 as a common characteristic of both groups. Within this population, donor-specific T cells were dominant. In both groups, increased numbers of activated (IL-2R+) CD8+ T lymphocytes were present on d 100. No accumulation of apoptotic IHL was observed on d 100. Their proportion was unchanged in the triple therapy group and slightly decreased in the CsA group compared to the syngeneic controls. CONCLUSIONS: The present study reveals that tolerant liver allografts are repopulated by donor-specific T lymphocytes. This phenomenon is independent of the type of applied immunosuppression. The persistence of activated CD8+ T cells in the phase of proven donor-specific tolerance on d 100 indicates that liver tolerance is associated with the state of a permanent intragraft immune activation. It seems that the coexistence of donor cells with infiltrating recipient cells within liver grafts, termed intrahepatic cell chimerism, is characteristic for tolerated liver allografts.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Quimera , Ciclosporina/uso terapêutico , Tolerância Imunológica , Transplante de Fígado/imunologia , Fígado/patologia , Animais , Apoptose/efeitos dos fármacos , Linfócitos T CD8-Positivos/patologia , Quimioterapia Combinada , Sobrevivência de Enxerto/efeitos dos fármacos , Contagem de Leucócitos , Leucócitos/patologia , Leucócitos/fisiologia , Fígado/fisiopatologia , Masculino , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Ratos Endogâmicos , Linfócitos T/patologia , Fatores de Tempo , Doadores de Tecidos , Transplante Homólogo
7.
Vasa ; 31(1): 48-55, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11951699

RESUMO

BACKGROUND: Graft infection after vascular prosthetic reconstruction for the treatment of peripheral arterial occlusive disease (PAOD) is a rare but severe complication with poor outcome. The options for surgical treatment are not uniformly accepted and remain controversial. PATIENTS AND METHODS: We retrospectively analyzed the histories of 30 patients treated for prosthetic graft infection (Szilagyi grade III) in our hospital between 1994 and 1999 to determine which forms of treatment were best suited for which types of patient. In the majority of cases the initial treatment was lower-extremity bypass surgery. The most frequent location of infection was the groin (73%). Staphylococci (13% of which were methicillin resistant) were the most common type of bacteria. The overall incidence of prosthetic infection was 2.3%. RESULTS: After confirmation of the infection by computed tomography (CT) or white blood cell scintigraphy, one of the following 5 forms of surgical treatment was performed: 1. Removal of the infected prosthesis and its simultaneous replacement by an autologous vein bypass. 2. Bypass removal and secondary replacement by an autologous vein. 3. Extra-anatomical replacement. 4. Graft removal and primary amputation. 5. Local therapy with debridement and secondary wound healing. In some patients primary amputation after graft infection was necessary to prevent further deterioration with fulminant sepsis. The overall mortality was 17%, the amputation rate was 60%. CONCLUSIONS: The best results were achieved by early complete removal of the alloplastic material and one-step replacement by either an autologous vein or extra-anatomic bypass. This resulted in a limb salvage rate of 54% and 40% and mortality rates of 9% and 0%, respectively.


Assuntos
Prótese Vascular , Infecções Relacionadas à Prótese/cirurgia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Resistência a Meticilina , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/epidemiologia , Reoperação , Estudos Retrospectivos , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/cirurgia
8.
Hernia ; 18(5): 691-700, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25112382

RESUMO

INTRODUCTION: Mesh infection is a severe complication after incisional hernia repair and occurs in 1-3 % of all open mesh implantations. For this reason, topical antimicrobial agent applied directly to the mesh is often used procedure. So far, however, this procedure lacks a scientific basis. MATERIALS AND METHODS: Two different meshes (Parietex™, Covidien; Ultrapro™, Ethicon Johnson & Johnson) were incubated with increasing amounts of three different Staphylococcus aureus strains (ATCC 25923; Mu50; ST239) with or without gentamicin and growth ability were determined in vitro. To further address the question of the systemic impact of topic gentamicin, serum levels were analyzed 6 and 24 h after implantation of gentamicin-impregnated multifilament meshes in 19 patients. RESULTS: None of the gentamicin-impregnated meshes showed any bacterial growth in vitro. This effect was independent of the mesh type for all the tested S. aureus strains. In the clinical setting, serum gentamicin levels 6 h after implantation of the gentamicin-impregnated meshes were below the through-level (range 0.4-2.9 mg/l, mean 1.2 ± 0.7 mg/l). After 24 h the gentamicin serum levels in all patients had declined 90-65 % of the 6 h values. CONCLUSION: Local application of gentamicin to meshes can completely prevent the growth of even gentamicin-resistant S. aureus strains in vitro. The systemic relevance of gentamicin in the clinical controls showed to be very low, without reaching therapeutic concentrations.


Assuntos
Antibacterianos/administração & dosagem , Contaminação de Equipamentos/prevenção & controle , Gentamicinas/administração & dosagem , Hérnia Ventral/cirurgia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Telas Cirúrgicas/microbiologia , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/sangue , Monitoramento de Medicamentos , Feminino , Gentamicinas/sangue , Humanos , Complicações Intraoperatórias/prevenção & controle , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento
9.
Cardiovasc Intervent Radiol ; 35(1): 198-202, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21431968

RESUMO

Spontaneous rupture of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) is a rare and life-threatening complication. Pathophysiologic mechanisms are not yet fully known; it is suggested that rupture is preceded by reactive tissue edema and intratumerous bleeding, leading to a rapid expansion of tumour mass with risk of extrahepatic bleeding in the case of subcapsular localisation. This case report discusses a sudden, unexpected lethal complication in a 74 year-old male patient treated with TACE using DC Bead loaded with doxorubicin (DEBDOX) in a progressive multifocal HCC.


Assuntos
Carcinoma Hepatocelular/terapia , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/terapia , Idoso , Angiografia , Meios de Contraste/administração & dosagem , Evolução Fatal , Humanos , Iopamidol/administração & dosagem , Iopamidol/análogos & derivados , Masculino , Microesferas , Ruptura Espontânea , Tomografia Computadorizada por Raios X
13.
HPB (Oxford) ; 9(4): 302-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18345309

RESUMO

BACKGROUND: The appropriate management of the pancreatic remnant following distal pancreatic resection remains a clinically relevant problem. We carried out a retrospective analysis which focused on this issue and compared the two favored techniques of suture and staple closure. PATIENTS AND METHODS: Forty-six patients underwent distal pancreatectomy between October 1999 and January 2006. The patients were retrospectively analysed based on the management of the remaining pancreatic gland. Thirty-seven patients had suture and nine patients had staple closure. The morbidity, mortality, incidence of pancreatic fistula, necessity of secondary surgical intervention, and the duration of hospital stay for the two groups were compared. Pancreatic fistula was considered according to the novel international standard definition (ISGPF). In addition, subgroup analysis of patients receiving octreotide was carried out. RESULTS: Overall, postoperative morbidity due to pancreatic fistula occurred in seven patients (19%) after suture and in one patient (11%) after staple closure (p = 0.54), with no deaths. The number of patients with surgical revision related to pancreatic leakage was two (5%) after suture closure vs no revision after staple closure (p = 0.65). The median number of total hospital days for the suture group was 19 (range 7-78 days) vs 21 (range 12-96 days) for the stapler group (p = 0.21). No significant benefit for the octreotide application could be determined. CONCLUSION: According to the data, no significant difference for either suture or stapler closure was observed, with the tendency for staple closure to be superior.

14.
Am J Transplant ; 7(5): 1091-102, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17456197

RESUMO

The clinical success of new treatment strategies aiming on inducing permanent graft acceptance will rely on the ability to determine whether specific unresponsiveness to donor alloantigens has developed and for how long it is maintained. To identify markers for such posttransplant monitoring, genes differentially expressed by graft infiltrating leukocytes during tolerance induction or rejection after kidney transplantation in rats were compared. A subsequently performed full kinetic analysis in two different transplant models, kidney and heart, in two species, rat and mouse identified two markers (TOAG-1, alpha-1,2-mannosidase) with high specificity and reproducibility, which are highly expressed during induction and maintenance of acceptance, and downregulated during rejection. Expression level of these markers showed a strong positive correlation with graft function. In addition, expression of both genes was downregulated in the peripheral blood and the graft prior to rejection, suggesting that these markers may be useful for monitoring in clinical transplantation where peripheral blood is the most easily accessible patient sample. Interestingly, downregulation of TOAG-1 and alpha-1,2-mannosidase expression occurred in graft infiltrating cells and expression of both genes was also downregulated after T-cell activation in vitro.


Assuntos
Marcadores Genéticos/fisiologia , Rejeição de Enxerto/genética , Sobrevivência de Enxerto/genética , Transplante de Coração/fisiologia , Transplante de Rim/fisiologia , Manosidases/genética , Animais , Complexo CD3/genética , Complexo CD3/fisiologia , Regulação da Expressão Gênica/fisiologia , Marcadores Genéticos/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/fisiopatologia , Sobrevivência de Enxerto/imunologia , Sobrevivência de Enxerto/fisiologia , Leucócitos/metabolismo , Masculino , Manosidases/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Perforina , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/fisiologia , Valor Preditivo dos Testes , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos , Transplante Homólogo
15.
Mol Gen Genet ; 178(1): 237-40, 1980 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6929948

RESUMO

The length of the terminal redundant regions in T7 DNA has been determined by two methods. One involved the specific labeling and isolation of the redundant DNA fragment and determination of the molecular weight by polyacrylamide gel electrophoresis. A value of 150 +/- 10 nucleotide pairs was obtained. The other determination based on a correlation of the melting temperature of the redundant region to that of whole T7 DNA confirmed the result obtained by the first method.


Assuntos
Replicação do DNA , DNA Viral/análise , Fagos T/genética , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Peso Molecular
16.
Transpl Int ; 13 Suppl 1: S465-70, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11112055

RESUMO

Long-term graft acceptance and tolerance induction after allogeneic rat liver transplantation are well described. However, the underlying mechanisms remain unclear. In this study we investigated the cellular events within the liver graft during initial immunosuppression and long-term acceptance. Orthotopic liver transplantation was performed in the Dark Agouti (DA)-to-Lewis (LEW) and LEW-to-DA rat strain combination. In order to achieve long-term acceptance, LEW recipients of DA livers were treated with two different short-term therapies. Non-parenchymal cells (NPC) were isolated from liver allografts on days + 10 and + 100 after transplantation and donor-specific leukocytes were immunophenotyped by flow cytometry. Both the monotherapy and triple therapy prolonged graft survival (> 100 days). Liver allografts from LEW donors into DA recipients were spontaneously accepted across a complete MHC mismatch without immunosuppression. Liver allograft rejection was induced by infiltrating alloreactive immunocompetent cells. But the intensities of cell infiltration in the early and late phases after transplantation did not correlate with eventual outcome. Donor-specific NPC decreased to 18-25% on day + 10 in both therapeutic groups, but had rebounded to up to 40% by day + 100. Recurrence of donor-specific cells was caused almost exclusively by rising T cell counts. The persistence of dendritic cells in the late phase after transplantation could be clearly demonstrated. Repopulation by donor-specific T lymphocytes was observed in long-term accepted liver grafts. This recurrence may be based on the differentiation of liver-derived progenitor cells. The persistent coexistence of donor and recipient cells within the liver allograft (intrahepatic chimerism) appears to be characteristic and may be important for long-term acceptance.


Assuntos
Sobrevivência de Enxerto/imunologia , Transplante de Fígado/imunologia , Quimeras de Transplante , Animais , Anticorpos Monoclonais/uso terapêutico , Ciclosporina/uso terapêutico , Células Dendríticas/imunologia , Teste de Histocompatibilidade , Imunossupressores/uso terapêutico , Masculino , Ratos , Ratos Endogâmicos Lew , Ratos Endogâmicos , Linfócitos T/imunologia , Transplante Homólogo/imunologia
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