Summary Organ donor shortage for infant liver transplant recipients has lead to an increase in splitting and living donation. For cases in which even transplantation of the left lateral graft (Couinaud’s segments II + III) results in a “large for size situation” with an estimated graft body weight ratio (GBWR) of >4%, monosegmental liver transplantation was developed. This, however, bears complications because of greater parenchymal surface and suboptimal vascular flow. We exclusively use the left lateral graft from living donors or split grafts. Temporary abdominal closure is attempted in cases of increased pressure. We report of 41 pediatric transplants in 38 children ≤10 kg. Within this group, there were 23 cases with a GBWR of ≥4, and 15 cases with a GBWR <4. There was no statistical difference in vascular or biliary complications. Despite a more frequent rate of temporary abdominal closure, we did not find a higher rate of intra‐abdominal infections. Overall, patient and graft survival was excellent in both groups (one death, three re‐transplants). We noticed, however, that the ventro–dorsal diameter of the graft appears to be more relevant to potential graft necrosis than the actual graft size. In conclusion, the usage of monosegmental grafts seems unnecessary if transplantation of left lateral grafts is performed by an experienced multidisciplinary team, and temporary abdominal closure is favored in cases of increased abdominal pressure.

Recently, we generated cells with multipotent properties from blood monocytes that in vitro differentiate into various somatic cell types. This experimental study investigated whether these programmable cells of monocytic origin (PCMO) succeed to restore left ventricular function after myocardial infarction (MI).PCMO were generated from monocytes by exposition to RPMI medium containing M-CSF and IL-3 for 6 days. MI was induced in female Lewis

Continuous immunosuppressive treatment allows the majority of transplant recipients to accept their donated organ and prevent acute graft rejection. However, life-long suppression of the immune system to respond appropriately to infectious, fungal, and carcinogenic threats coincides with substantial morbidity and mortality for the host. Thus for the past five decades research in the field of transplantation medicine has focused on innovative strategies to induce graft tolerance to donor alloantigens, a state in which the recipient's lymphocytes have learned to accept the foreign organ or tissue as "self" without the need of permanent immunosuppression. The fact that individuals of the same species attack each other's tissues can be explained with the set of specific antigens, designated as major histocompatibility antigens, which are expressed on each cell of the body and normally widely differ between nonrelated individuals. According to the genetic laws of transplantation, survival of allogeneic grafts is correlated with the number of differences among these histocompatibility antigens. An important exception to this rule can be observed in pregnant women who tolerate their unborn conceptus expressing a full set of nonmaternal antigens inherited by the father. The exact mechanisms of immune privilege exhibited by embryonic tissue during prenatal development have not yet been characterized in each detail. The field of maternofetal immunobiology has lately emerged as a new scientific branch in immunology which is gathering useful insights for future innovative tolerance strategies to prevent allogeneic graft rejection.

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The efficacy of MHC class I-derived peptides to induce tolerance was tested in a cardiac transplantation model. Two 25-mer peptides from the polymorphic region of the DA class I molecule (RT1.Aa) were synthesized by F-moc chemistry and injected intrathymically or intraperitoneally into LEW (RT1.1) responder animals. Intrathymic treatment of the recipient animals with peptide 1 (residues 56-80) accompanied by intraperitoneal treatment with peptide 4 (residues 96-120) led to indefinite survival of allogeneic DA cardiac allografts (n = 7; > 100 days). The tolerogenicity of both peptides differed according to the site of inoculation, as donor-specific tolerance was only observed after administration of peptide 1 into the thymus and injection of peptide 2 into the abdominal cavity of LEW recipients, but not vice versa. Donor-specific tolerance was confirmed in vivo by grafting of full-thickness skin and in vitro by appropriate proliferation and cytotoxicity assays using donor and third-party rats. Donor-specific tolerance was associated with up-regulation of interleukin-4, transforming growth factor beta, and interleukin-10 gene expression within cardiac allografts, thus suggesting intrathymic clonal deletion and external suppression with expansion of T-helper 2-type lymphocytes as the underlying mechanisms of tolerance induction.