Uterus transplantation (UTx) has been successfully introduced as a treatment option for women with absolute uterine factor infertility (AUFI). AUFI representing approximately 3% to 5% of the female general population is linked to either congenital uterine agenesis (Mayer-Rokitansky-Küster-Hauser syndrome), major congenital uterine malformation (hypoplastic uterus, fraction of bicornuate/unicornuate uterus), a surgically absent uterus, or an acquired condition (intrauterine adhesions, leiomyoma) linked to uterine malfunction that causes implantation failure or defect placentation. The world's first clinical uterus transplant was performed in 2000. However, a hysterectomy became necessary shortly after the surgery due to uterine necrosis. In 2011, a group in Turkey reported on a surgically successful deceased donor transplant; however, this procedure has, to date, not resulted in a healthy live birth, the ultimate goal of UTx. Building on an extensive experimental background in various animal models, including primates, the Gothenburg group led by Brännström reported on the first delivery of a healthy baby in a recipient of a live donor UTx in 2014. This event did not only show the feasibility of UTx, it also helped defining relevant areas of clinical and basic research. Use of a gestational surrogate carrier, is, at least in theory, an alternative for a woman with AUFI seeking genetic motherhood. However, in the clear majority of countries worldwide, gestational surrogacy is not practiced based on legal, ethical, or religious concerns. Of note, the overwhelming majority of surveyed women in the United Kingdom, a country which permits surrogacy, preferred UTx over gestational surrogacy and adoption. Moreover, randomly selected women of fertile age in Sweden preferred UTx over gestational surrogacy. A recent large survey in Japan with more than 3000 participants revealed that UTx had a twofold higher acceptance rate compared with gestational surrogacy. In a recent US survey exploring the potential of donating vascularized composite allografts, uterus donation achieved the highest priority. Thus, the acceptance of UTx as infertility treatment for women with AUFI is high, although the procedure remains in its infancy. Here, we provide an update of clinical activities, summarize achievements and challenges, and submit areas of research interests.

Epoxides from polyunsaturated fatty acids (PUFAs) are potent lipid mediators. In vivo stabilization of these epoxides by blockade of the soluble epoxide hydrolase (sEH) leads to anti-inflammatory, analgesic and normotensive effects. Therefore, sEH inhibitors (sEHi) are a promising new class of drugs. Herein, we characterized pharmacokinetic (PK) and pharmacodynamic properties of a commercially available potent sEHi 1-trifluoromethoxyphenyl-3-(1-propionylpiperidin-4-yl) urea (TPPU). Cell culture studies suggest its high absorption and metabolic stability. Following administration in drinking water to rats (0.2, 1, and 5 mg TPPU/L with 0.2% PEG400), TPPU’s blood concentration increased dose dependently within the treatment period to reach an almost steady state after 8 days. TPPU was found in all the tissues tested. The linoleic epoxide/diol ratios in the tissues were dose dependently increased, indicating significant sEH inhibition. Overall, administration of TPPU with the drinking water led to systemic distribution as well as high levels and thusmakes chronic sEH inhibition studies possible.

Background: Ischemia reperfusion injury (IRI) plays a major role in solid organ transplantation. The length of warm ischemia time is critical for the extent of tissue damage in renal IRI. In this experimental study we hypothesized that local release of labile heme in renal tissue is triggered by the duration of warm ischemia (15 vs. 45 min IRI) and mediates complement activation, cytokine release, and inflammation. Methods: To induce IRI, renal pedicle clamping was performed in male C57BL/6 mice for short (15 min) or prolonged (45 min) time periods. Two and 24 h after experimental ischemia tissue injury labile heme levels in the kidney were determined with an apo-horseradish peroxidase assay. Moreover, renal injury, cytokines, and C5a and C3a receptor (C5aR, C3aR) expression were determined by histology, immunohistochemistry and qPCR, respectively. In addition, in vitro studies stimulating bone marrow-derived macrophages with LPS and the combination of LPS and heme were performed and cytokine expression was measured. Results: Inflammation and local tissue injury correlated with the duration of warm ischemia time. Labile heme concentrations in renal tissue were significantly higher after prolonged (45 min) as compared to short (15 min) IRI. Notably, expression of the inducible heme-degrading enzyme heme oxygenase-1 (HO-1) was up-regulated in kidneys after prolonged, but not after short IRI. C5aR, the pro-inflammatory cytokines IL-6 and TNF-α as well as pERK were up-regulated after prolonged, but not after short ischemia times. Consecutively, neutrophil infiltration and up-regulation of pro-fibrotic cytokines such as CTGF and PAI were more pronounced in prolonged IRI in comparison to short IRI. In vitro stimulation of macrophages with LPS revealed that IL-6 expression was enhanced in the presence of heme. Finally, administration of the heme scavenger human serum albumin (HSA) reduced the expression of pro-inflammatory cytokines, C3a receptor and improved tubular function indicated by enhanced alpha 1 microglobulin (A1M) absorption after IRI. Conclusions: Our data show that prolonged duration of warm ischemia time increased labile heme levels in the kidney, which correlates with IRI-dependent inflammation and up-regulation of anaphylatoxin receptor expression.

Acute kidney injury (AKI) increases the risk of morbidity and mortality after major surgery and transplantation. We investigated the effect of PKC-ε deficiency on AKI and ischemic allograft damage after kidney transplantation. PKC-ε-deficient and wild type (WT) control mice were subjected to 35 min of renal pedicle clamping to induce AKI. PKC-ε deficiency was associated with a marked improvement in survival and an attenuated loss of kidney function. Furthermore, functional MRI experiments revealed better renal perfusion in PKC-ε-deficient mice than in WT mice one day after IRI. Acute tubular necrosis and neutrophil infiltration were markedly reduced in PKC-ε-deficient mice. To determine whether this resistance to ischemia-reperfusion injury resulted from changes in local renal cells or infiltrating leukocytes, we studied a life-supporting renal transplant model of ischemic graft injury. We transplanted kidneys from H(2b) PKC-ε-deficient mice (129/SV) and their corresponding WT littermates into major histocompatibility complex-incompatible H(2d) recipients (BALB/c) and induced ischemic graft injury by prolonged cold ischemia time. Recipients of WT allografts developed severe renal failure and died within 10 days of transplantation. Recipients of PKC-ε-deficient allografts had better renal function and survival; they had less generation of ROS and upregulation of proinflammatory proteins (i.e., ICAM-1, inducible nitric oxide synthase, and TNF-α) and showed less tubular epithelial cell apoptosis and inflammation in their allografts. These data suggest that local renal PKC-ε expression mediates proapoptotic and proinflammatory signaling and that an inhibitor of PKC-ε signaling could be used to prevent hypoxia-induced AKI.