Home  About us  Contact
 

Graft Regeneration (graft + regeneration)

Distribution by Scientific Domains
Medical Sciences100%

Kinds of Graft Regeneration

  • liver graft regeneration
    		•

    Selected Abstracts

    Liver Graft Regeneration in Right Lobe Adult Living Donor Liver Transplantation

    AMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2009
    Y.-F. Cheng
    Optimal portal flow is one of the essentials in adequate liver function, graft regeneration and outcome of the graft after right lobe adult living donor liver transplantation (ALDLT). The relations among factors that cause sufficient liver graft regeneration are still unclear. The aim of this study is to evaluate the potential predisposing factors that encourage liver graft regeneration after ALDLT. The study population consisted of right lobe ALDLT recipients from Chang Gung Memorial Hospital-Kaohsiung Medical Center, Taiwan. The records, preoperative images, postoperative Doppler ultrasound evaluation and computed tomography studies performed 6 months after transplant were reviewed. The volume of the graft 6 months after transplant divided by the standard liver volume was calculated as the regeneration ratio. The predisposing risk factors were compiled from statistical analyses and included age, recipient body weight, native liver disease, spleen size before transplant, patency of the hepatic venous graft, graft weight-to-recipient weight ratio (GRWR), posttransplant portal flow, vascular and biliary complications and rejection. One hundred forty-five recipients were enrolled in this study. The liver graft regeneration ratio was 91.2 ± 12.6% (range, 58,151). The size of the spleen (p = 0.00015), total portal flow and GRWR (p = 0.005) were linearly correlated with the regeneration rate. Patency of the hepatic venous tributary reconstructed was positively correlated to graft regeneration and was statistically significant (p = 0.017). Splenic artery ligation was advantageous to promote liver regeneration in specific cases but splenectomy did not show any positive advantage. Spleen size is a major factor contributing to portal flow and may directly trigger regeneration after transplant. Control of sufficient portal flow and adequate hepatic outflow are important factors in graft regeneration. [source]

    Hematopoietic stem cells mobilized by granulocyte colony-stimulating factor partly contribute to liver graft regeneration after partial orthotopic liver transplantation

    LIVER TRANSPLANTATION, Issue 7 2006
    Feng Liu
    On the basis of the recently recognized potential of hematopoietic stem cells (HSCs) to give rise to hepatocytes, we investigated whether HSCs mobilized by granulocyte colony-stimulating factor (G-CSF) or G-CSF per se could contribute to faster recovery and promote tissue reparation after rats' (cross-sex) partial orthotopic liver transplantation (PLTx). Sex-mismatched (female to male) syngeneic rat PLTx was established. The recipients were repeatedly administrated recombinant G-CSF for 5 consecutive days before (G-CSF + PLTx group) and after PLTx (PLTx + G-CSF group). Compared with those in PLTx group, CD34+ cells in peripheral blood and portal tract region increased from day 1 to 7 after transplantation in G-CSF + PLTx group and from day 3 to 14 after transplantation in PLTx + G-CSF group, respectively, which suggested that CD34+ HSCs were mobilized and migrated into liver graft. Compared with that in G-CSF + PLTx and PLTx groups, there was a higher survival rate in the PLTx + G-CSF group. On day 3 after surgery, the level of aspartate aminotransferase and alanine aminotransferase were lower, whereas the mitosis index, proliferating cell nuclear antigen,positive nuclei, bromodeoxyuridine (BrdU) incorporation, and graft-to-recipient weight ratio were higher in the PLTx + G-CSF group. In contrast, these parameters had no significant difference between G-CSF + PLTx and PLTx groups. To define the origin of proliferating cells reconstituting liver after injury, sry+ (sex-determining region for Y chromosome) and sry+/cytokeratin 19+ (CK19) cells were quantitated. Higher percentage of sry+ and sry+/CK19+ cells in PLTx + G-CSF was detected than in G-CSF + PLTx groups on day 14 after surgery, although the liver engraftment rate still remained rather low. Some of the sry+/CK19+ cells in the portal tract areas were similar to hepatic oval cells/cholangiocytes. In conclusion, G-CSF administration after PLTx greatly improved survival rate and liver regeneration of partial graft, partly by its mobilizing HSCs into the injured liver to differentiate into hepatocytes through hepatic oval cells'/cholangiocytes' engraftment. Liver Transpl 12:1129,1137, 2006. © 2006 AASLD. [source]

    Pretreatment With Portal Venous Ultraviolet B Irradiated Donor Alloantigen Promotes Donor-Specific Tolerance to Rat Nerve Allografts,

    THE LARYNGOSCOPE, Issue 3 2001
    Eric M. Genden MD
    Abstract Objective To determine if a single intraportal inoculation of ultraviolet B-irradiated (UVB) donor splenocytes can prevent nerve allograft rejection and confer donor-specific immunotolerance to rat nerve allograft segments. Methods Age-matched, class I and class II major histocompatibility complex (MHC) mismatched Buffalo (RT1b) rats were transplanted with a syngeneic nerve isograft, a Lewis (RT1l) nerve allograft, or a Brown-Norway (RT1n) rat nerve allograft segment. Control Buffalo rats in group I received a 3.0-cm Lewis (RT11) sciatic-posterior tibial interposition nerve allograft without pretreatment;group II Buffalo rats received a syngeneic Buffalo nerve isograft without pretreatment. Group III Buffalo recipients were inoculated with 2.5 × 107 UVB-irradiated Lewis donor splenocyte cells by portal venous administration 7 days before transplantation with a 3.0-cm sciatic-posterior tibial nerve allograft from a Lewis (RT11) or a third party Brown-Norway rat (RT1n) donor (group IV). Nerve graft regeneration was assessed with walking track analysis, nerve conduction studies, retrograde neural tracing, nerve graft histology, and morphometry. Recipient immune tolerance was assessed through in vitro immunological assessment. Results Pretreatment with UVB-irradiated donor splenocytes 7 days before transplantation prevented nerve allograft rejection. Pretreated animals receiving a nerve allograft recovered limb function, and demonstrated morphological, histological, and electrophysiologic parameters of nerve regeneration similar to that measured in rats receiving a nerve isograft. In vitro immunological assessment by mixed lymphocyte culture (MLC), cytotoxic T lymphocyte (CTL) assay, limiting dilution analysis (LDA) of helper (pTH) and cytotoxic (pCTL) precursor frequencies, and IL-2 production demonstrated a marked donor-specific suppression in allografted animals pretreated with intraportal UVB-irradiated donor splenocytes. These assessments correlated with indefinite acceptance of donor nerve allografts. Conclusions A single pretreatment with a single intraportal dose of UVB-modified donor antigen specifically induces tolerance to peripheral nerve allografts in rats. [source]

    Liver Graft Regeneration in Right Lobe Adult Living Donor Liver Transplantation

    AMERICAN JOURNAL OF TRANSPLANTATION, Issue 6 2009
    Y.-F. Cheng
    Optimal portal flow is one of the essentials in adequate liver function, graft regeneration and outcome of the graft after right lobe adult living donor liver transplantation (ALDLT). The relations among factors that cause sufficient liver graft regeneration are still unclear. The aim of this study is to evaluate the potential predisposing factors that encourage liver graft regeneration after ALDLT. The study population consisted of right lobe ALDLT recipients from Chang Gung Memorial Hospital-Kaohsiung Medical Center, Taiwan. The records, preoperative images, postoperative Doppler ultrasound evaluation and computed tomography studies performed 6 months after transplant were reviewed. The volume of the graft 6 months after transplant divided by the standard liver volume was calculated as the regeneration ratio. The predisposing risk factors were compiled from statistical analyses and included age, recipient body weight, native liver disease, spleen size before transplant, patency of the hepatic venous graft, graft weight-to-recipient weight ratio (GRWR), posttransplant portal flow, vascular and biliary complications and rejection. One hundred forty-five recipients were enrolled in this study. The liver graft regeneration ratio was 91.2 ± 12.6% (range, 58,151). The size of the spleen (p = 0.00015), total portal flow and GRWR (p = 0.005) were linearly correlated with the regeneration rate. Patency of the hepatic venous tributary reconstructed was positively correlated to graft regeneration and was statistically significant (p = 0.017). Splenic artery ligation was advantageous to promote liver regeneration in specific cases but splenectomy did not show any positive advantage. Spleen size is a major factor contributing to portal flow and may directly trigger regeneration after transplant. Control of sufficient portal flow and adequate hepatic outflow are important factors in graft regeneration. [source]

    Significance of CT Attenuation Value in Liver Grafts Following Right Lobe Living-Donor Liver Transplantation

    AMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2005
    Taku Iida
    In adult living-donor liver transplantation (LDLT), the assessment of the allograft functional reserve is important for adequate graft regeneration. From March 2002 to December 2003, 30 adult recipients underwent right lobe LDLT. Mean CT attenuation values (CT-AVs) in the graft were measured on unenhanced CT for 6 months after LDLT. The histological features of the graft parenchyma were evaluated with post-operative liver biopsy specimens. Mean CT-AVs after LDLT were decreased significantly from the pre-operative values, recovered to over 60 HU within 6 months. There was a positive linear correlation between the CT-AVs and the receptor index (LHL15) in technetium-99m-diethylenetriaminepenta-acetic acid-galactosyl-human serum albumin (99mTc-GSA) liver scintigraphy (r = 0.803, p = 0.005). The recipients were divided into two groups according to the CT-AV at one post-operative week (group H; ,55HU, group L; <55HU). The low CT-AVs, under 55 HU, in group L were prolonged for 3 months compared with those in group H (p < 0.05). The 1-year cumulative survival rate was 94.7% and 45.5% in groups H and L, respectively (p = 0.014). Histological findings revealed that the parenchymal damage was severe in the grafts with low CT-AVs. The CT-AVs in the grafts may be a useful parameter for assessing the allograft functional reserve. [source]