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Obesity initiates a chronic inflammatory network linked to perioperative complications and increased acute rejection rates in organ transplantation. Bariatric surgery is the most effective treatment of obesity recommended for morbidly obese transplant recipients. Here, we delineated the effects of obesity and bariatric surgery on alloimmunity and transplant outcomes in diet-induced obese (DIO) mice. Allograft survival was significantly shorter in DIO-mice. When performing sleeve gastrectomies (SGx) prior to transplantation, we found attenuated T cell-derived alloimmune responses resulting in prolonged allograft survival. Administering taurodeoxycholic acid (TDCA) and valine, metabolites depleted in DIO-mice and restored through SGx, prolonged graft survival in DIO-mice comparable with SGx an dampened Th1 and Th17 alloimmune responses while Treg frequencies and CD4+ T cell-derived IL-10 production were augmented. Moreover, in recipient animals treated with TDCA/valine, levels of donor-specific antibodies had been reduced. Mechanistically, TDCA/valine restrained inflammatory M1-macrophage polarization through TGR5 that compromised cAMP signaling and inhibited macrophage-derived T cell activation. Consistently, administering a TGR5 agonist to DIO-mice prolonged allograft survival. Overall, we provide novel insights into obesity-induced inflammation and its impact on alloimmunity. Furthermore, we introduce TDCA/valine as a noninvasive alternative treatment for obese transplant patients.

Abnormalities of or reductions in GABAergic interneurons are implicated in the pathology of severe neuropsychiatric disorders, for which effective treatments are still elusive. Transplantation of human stem cell-derived interneurons is a promising cell-based therapy for treatment of these disorders. In mouse xenograft studies, human stem cell-derived-interneuron precursors could differentiate in vivo, but required a prolonged time of four to seven months to migrate from the graft site and integrate with the host tissue. This poses a serious roadblock for clinical translation of this approach. For transplantation to be effective, grafted neurons should migrate to affected areas at a faster rate. We have previously shown that endothelial cells of the periventricular vascular network are the natural substrates for GABAergic interneurons in the developing mouse forebrain, and provide valuable guidance cues for their long-distance migration. In addition, periventricular endothelial cells house a GABA signaling pathway with direct implications for psychiatric disease origin. In this study we translated this discovery into human, with significant therapeutic implications. We generated human periventricular endothelial cells, using human pluripotent stem cell technology, and extensively characterized its molecular, cellular, and functional properties. Co-culture of human periventricular endothelial cells with human interneurons significantly accelerated interneuron migration in vitro and led to faster migration and wider distribution of grafted interneurons in vivo, compared to neuron-only transplants. Furthermore, the co-transplantation strategy was able to rescue abnormal behavioral symptoms in a pre-clinical model of psychiatric disorder, within 1 month after transplantation. We anticipate this strategy to open new doors and facilitate exciting advances in angiogenesis-mediated treatment of psychiatric disorders.

Age impacts alloimmunity. Effects of aging on T‐cell metabolism and the potential to interfere with immunosuppressants have not been explored yet. Here, we dissected metabolic pathways of CD4+ and CD8+ T cells in aging and offer novel immunosuppressive targets. Upon activation, CD4+ T cells from old mice failed to exhibit adequate metabolic reprogramming resulting into compromised metabolic pathways, including oxidative phosphorylation (OXPHOS) and glycolysis. Comparable results were also observed in elderly human patients. Although glutaminolysis remained the dominant and age‐independent source of mitochondria for activated CD4+ T cells, old but not young CD4+ T cells relied heavily on glutaminolysis. Treating young and old murine and human CD4+ T cells with 6‐diazo‐5‐oxo‐l‐norleucine (DON), a glutaminolysis inhibitor resulted in significantly reduced IFN‐γ production and compromised proliferative capacities specifically of old CD4+ T cells. Of translational relevance, old and young mice that had been transplanted with fully mismatched skin grafts and treated with DON demonstrated dampened Th1‐ and Th17‐driven alloimmune responses. Moreover, DON diminished cytokine production and proliferation of old CD4+ T cells in vivo leading to a significantly prolonged allograft survival specifically in old recipients. Graft prolongation in young animals, in contrast, was only achieved when DON was applied in combination with an inhibition of glycolysis (2‐deoxy‐d‐glucose, 2‐DG) and OXPHOS (metformin), two alternative metabolic pathways. Notably, metabolic treatment had not been linked to toxicities. Remarkably, immunosuppressive capacities of DON were specific to CD4+ T cells as adoptively transferred young CD4+ T cells prevented immunosuppressive capacities of DON on allograft survival in old recipients. Depletion of CD8+ T cells did not alter transplant outcomes in either young or old recipients. Taken together, our data introduce an age‐specific metabolic reprogramming of CD4+ T cells. Targeting those pathways offers novel and age‐specific approaches for immunosuppression., Upon activation, old CD4+ T cells failed to exhibit adequate metabolic reprogramming resulting into compromised metabolic pathways. Since glutaminolysis displayed their dominant fuel source for mitochondria, treatment with a glutaminolysis inhibitor (DON) restricted activation, proliferative capacities and cytokine production in an age‐specific manner. These effects translated into dampened alloimmune responses and dramatically prolonged allograft survival specifically in old transplant recipients.

Obesity is widespread and linked to various co-morbidities. Bariatric surgery has been identified as the only effective treatment, promoting sustained weight loss and the remission of co-morbidities.We performed sleeve-gastrectomies (SGx) in a pre-clinical mouse model of diet-induced obesity (DIO), delineating the effects on long-term remission from obesity. SGx resulted in sustained weight loss and improved glucose tolerance. Mass-spectrometric metabolomic profiling revealed significantly reduced systemic levels of taurodeoxycholic acid (TDCA) and L-valine in DIO mice. Notably, TDCA and L-Valine levels were restored after SGx in both human and mice to levels comparable with lean controls.Strikingly, combined systemic treatment with TDCA and valine induced a profound weight loss in DIO mice analogous to effects observed after SGx. Utilizing indirect calorimetry, we confirmed reduced food intake as causal for TDCA/valine-mediated weight loss via a central inhibition of the melanin-concentrating hormone.In summary, we identified restored TDCA/valine levels as an underlying mechanism of SGx-derived effects on weight loss. Of translational relevance, TDCA and L-valine are presented as novel agents promoting weight loss while reversing obesity-associated metabolic disorders.

Frailty has gained clinical relevance. While the condition may negatively impact outcomes, organ transplantation may also improve frailty. Notably, available assessment tools are broad and have not allowed for a detailed analysis or prognosis. Frailty has been linked to adverse surgical outcomes while imparting on immune competency. Immunosuppressive treatment may therefore require modifications in frail patients, and effects on drug metabolism may need consideration. Moreover, cognitive impairment may impact compliance. Here, we provide a comprehensive update on clinical features, diagnostics, consequences on immunity and immunosuppression, and clinical outcomes. Clinical studies have shown promising outcomes for some frail transplant recipients. Relevant open questions include patient selection, adaptation of immunosuppression, potential to improve frailty, compliance, and transplant outcomes.

Elderly organ transplant recipients have remained underrepresented in clinical trials, despite representing a rapidly growing population. Here, we assessed age-specific effects of CTLA4-Ig (cytotoxic T-lymphocyte antigen 4-Ig), a fusion protein blocking costimulatory signaling between antigen-presenting cells and T cells through CD28. Cardiac allografts in young mice (2-3 months) treated with CTLA4-Ig survived indefinitely, whereas 80% of old recipients (18 months) had lost their graft after 100 days. CTLA4-Ig was also significantly less effective in older recipients of skin transplants. CTLA4-Ig reduced CD4+ central memory and effector memory T cells and diminished systemic interferon-gamma levels only in young recipients. These differences corresponded to a reduced expression of CD28 on antigen-experienced CD4+ T cells in old mice. In support, adoptive transfer of old CD4+ T cells that were transfected with a lentiviral vector inducing constant expression of CD28 accelerated the rejection of allogeneic skin grafts in young RAG2-/- recipient mice. Regulatory T cells (Tregs), in contrast, demonstrated an increased expression of CD28 with aging and CTLA4-Ig treatment in old recipients resulted in reduced frequencies, compromised proliferation, and diminished suppressive capacity of Tregs. These findings may prove to have unique clinical consequences for immunosuppression in the growing population of elderly transplant recipients.

Shanbiao Hu,1 Ling Li,2 Wei Huang,3 Jie Liu,4 Gongbin Lan,1 Shaojie Yu,1 Longkai Peng,1 Xubiao Xie,1 Luoyan Yang,2 Yeqi Nian,2 Yinhuai Wang2 1Department of Urological Organ Transplantation, The Second Xiangya Hospital of Central South University, Changsha, China; 2Department of Urology, The Second Xiangya Hospital of Central South University, Changsha, China; 3Research Center of Carcinogenesis and Targeted Therapy, Xiangya Hospital, Central South University, Changsha, China; 4Department of Pathology, Changsha Central Hospital, Changsha, China Background: Aberrant expression of CAV3.1, one of T-type Ca2+ channels, is reported to exert important functions in pathological processes, including carcinogenesis. However, its expression pattern and function in prostate cancer (PCa) remains unclear.Materials and methods: The expression pattern of CAV3.1 was analyzed in multiple ways, including online analysis in Oncomine database, experimental analyses in cell lines, and collected clinical specimens using immunohistochemistry, quantitative reverse transcription polymerase chain reaction, and Western blot. Then, CAV3.1 was downregulated in PCa cells to explore its functions.Results: Upregulated CAV3.1 in PCa tissues and cells was confirmed by analyzing mRNA expression datasets from Oncomine and quantitative reverse transcription polymerase chain reaction detection, respectively. Accordingly, significantly higher CAV3.1 protein level in PCa tissues specimens than that in benign prostatic hyperplasia tissues was indicated by immunohistochemical staining. In addition, CAV3.1 upregulation was positively associated with metastasis. Depletion of CAV3.1 impaired the proliferation, migration, and invasion ability of PCa cells demonstrating by cell functional experiments, such as CCK-8, cell cycle distribution, plate clone formation, scratch wound healing, and transwell invasion assays. Mechanistically, due to constrained Akt activity, CAV3.1 knockdown resulted in decreased level of CCND1, N-cadherin, and Vimentin, and increased level of E-cadherin whose expressions could be reversed by ectopic Akt expression. Similarly, ectopic Akt expression also rescued the inhibitory effects of CAV3.1 knockdown on cell functions like proliferation and migration in PCa cells.Conclusion: Upregulated CAV3.1 is positively associated with the development of PCa. CAV3.1 knockdown can inhibit PCa cell proliferation, migration, and invasion by suppressing AKT activity. Keywords: CAV3.1, PCa, AKT signaling, proliferation, invasion

Alloimmunity traditionally distinguishes short-lived, rapid and non-specific innate immune responses from adaptive immune responses that are characterized by a highly specific response initiated in a delayed fashion. Key players of innate immunity such as natural killer (NK) cells and macrophages present the first-line defense of immunity. The concept of unspecific responses in innate immunity has recently been challenged. The discovery of pattern recognition receptors (PRRs) has demonstrated that innate immune cells respond in a semi-specific fashion through the recognition of pathogen-associated molecular patterns (PAMPs) representing conserved molecular structures shared by large groups of microorganisms. Although immunological memory has generally been considered as exclusive to adaptive immunity, recent studies have demonstrated that innate immune cells have the potential to acquire memory. Here, we discuss allospecific features of innate immunity and their relevance in transplantation.

Septic shock is characterized by an excessive inflammatory response depicted in a cytokine storm that results from invasive bacterial and viral infections. Non-canonical inflammasome activation is crucial in the development of septic shock promoting pyroptosis and pro-inflammatory cytokine production via caspase-11 and Gasdermin-D (GSDMD). Here, we show that NAD+treatment protected mice towards bacterial and LPS induced endotoxic shock by blocking the non-canonical inflammasome specifically. NAD+administration impeded systemic IL-1β and IL-18 production and GSDMD-mediated pyroptosis of macrophages via the IFN-β/STAT-1 signaling machinery. More importantly, NAD+administration not only improved casp-11-/-survival but rendered WT mice completely resistant to septic shock via the IL-10 signaling pathway that was independent from the non-canonical inflammasome. Here, we delineated a two-sided effect of NAD+blocking septic shock through a specific inhibition of the non-canonical inflammasome and promoting immune homeostasis via IL-10, underscoring its unique therapeutic potential.

Aim: A gene set based systematic analysis strategy is used to investigate prostate tumors and its subclusters with focuses on similarities and differences of biological functions. Results: Dysregulation of methylation status, as well as RAS/RAF/ERK and PI3K-ATK signaling pathways, were found to be the most dramatic changes during prostate cancer tumorigenesis. Besides, neural and inflammation microenvironment is also significantly divergent between tumor and adjacent tissues. Insights of subclasses within prostate tumor cohorts revealed four different clusters with distinct gene expression patterns. We found that samples are mainly clustered by immune environments and proliferation traits. Conclusion: The findings of this article may help to advance the progress of identifying better diagnosis biomarkers and therapeutic targets.

T-cell immunity undergoes a complex and continuous remodeling with aging. Understanding those dynamics is essential in refining immunosuppression. Aging is linked to phenotypic and metabolic changes in T-cell immunity, many resulting into impaired function and compromised effectiveness. Those changes may impact clinical immunosuppression with evidences suggesting age-specific efficacies of some (CNI and mammalian target of rapamycin inhibitors) but not necessarily all immunosuppressants. Metabolic changes of T cells with aging have only recently been appreciated and may provide novel ways of immunosuppression. Here, we provide an update on changes of T-cell immunity in aging.

Vascularized composite allotransplants (VCAs) have unique properties because of diverse tissue components transplanted en mass as a single unit. In addition to surgery, this type of transplant also faces enormous immunological challenges that demand a detailed analysis of all aspects of alloimmune responses, organ preservation, and injury, as well as the immunogenicity of various tissues within the VCA grafts to further improve graft and patient outcomes. Moreover, the side effects of long-term immunosuppression for VCA patients need to be carefully balanced with the potential benefit of a non-life-saving procedure. In this review article, we provide a comprehensive update on limb and face transplantation, with a specific emphasis on the alloimmune responses to VCA, established and novel immunosuppressive treatments, and patient outcomes.

Fast-track surgery (FTS), which includes a series of evidence-based adjustments, is expected to reduce complications, relieve surgical stress reaction, accelerate recovery, and shorten hospitalization, as well as improve safety. The aim of this study was to critically evaluate the safety and effectiveness of FTS in Chinese prostate cancer (Pca) patients who underwent robot-assisted laparoscopic prostatectomy (RALP). A retrospective analysis was performed on 73 consecutive Chinese Pca patients who underwent RALP and who were divided into two groups: conventional surgery (CS) and FTS. Preoperative clinical data, intraoperative characteristics, postoperative outcomes and incidence of complications were compared between the two groups. No significant differences in preoperative parameters were observed between the two groups. Compared with the CS group, the FTS group showed a significantly shorter time to first flatus, time to regular diet, postoperative hospitalization time, lower incidence of complications, and lower reactions of postoperative stress and pain. Our study demonstrates that FTS is feasible and safe for Chinese Pca patients undergoing RALP and that it accelerates recovery, attenuates surgical stress response, and reduces morbidity compared to CS.

[Background] Given their unique capacity for antigen uptake, processing, and presentation, antigen-presenting cells (APCs) are critical for initiating and regulating innate and adaptive immune responses. We have previously shown the role of nicotinamide adenine dinucleotide (NAD+) in T-cell differentiation independently of the cytokine milieu, whereas the precise mechanisms remained unknown., [Objective] The objective of this study is to further dissect the mechanism of actions of NAD+ and determine the effect of APCs on NAD+-mediated T-cell activation., [Methods] Isolated dendritic cells and bone marrow–derived mast cells (MCs) were used to characterize the mechanisms of action of NAD+ on CD4+ T-cell fate in vitro. Furthermore, NAD+-mediated CD4+ T-cell differentiation was investigated in vivo by using wild-type C57BL/6, MC−/−, MHC class II−/−, Wiskott-Aldrich syndrome protein (WASP)−/−, 5C.C7 recombination-activating gene 2 (Rag2)−/−, and CD11b-DTR transgenic mice. Finally, we tested the physiologic effect of NAD+ on the systemic immune response in the context of Listeria monocytogenes infection., [Results] Our in vivo and in vitro findings indicate that after NAD+ administration, MCs exclusively promote CD4+ T-cell differentiation, both in the absence of antigen and independently of major APCs. Moreover, we found that MCs mediated CD4+ T-cell differentiation independently of MHC II and T-cell receptor signaling machinery. More importantly, although treatment with NAD+ resulted in decreased MHC II expression on CD11c+ cells, MC-mediated CD4+ T-cell differentiation rendered mice resistant to administration of lethal doses of L monocytogenes., [Conclusions] Collectively, our study unravels a novel cellular and molecular pathway that regulates innate and adaptive immunity through MCs exclusively and underscores the therapeutic potential of NAD+ in the context of primary immunodeficiencies and antimicrobial resistance.

Background. Although the elderly represents a rapidly growing population among transplant recipients, age-specific aspects have not been considered sufficiently in clinical trials. Moreover, age-specific effects of immunosuppressive therapies remain poorly understood. Methods. Here, we assessed the impact of rapamycin on alloimmune responses in old recipients using a fully major histocompatibility complex-mismatched murine transplantation model. Results. Old untreated recipients displayed a prolonged skin graft survival compared to their young counterparts, an observation that confirmed data of our previous experiments. Rapamycin led to a significant prolongation of graft survival in both young and old recipients. However, graft survival was age-dependent and extended in old versus young recipients (19 days vs 12 days, P = 0.004). This age-specific effect was not linked to changes in frequencies or subset composition of either cluster of differentiation (CD)8(+) or CD4(+) Tcells. Moreover, antiproliferative effects of rapamycin on CD8(+) and CD4(+) T cells as assessed by in vivo bromdesoxyuridine incorporation were comparable and age-independent. In contrast, the systemic production of IL-10 was markedly elevated in old recipients treated with rapamycin. In parallel to this shift in cytokine balance, IFN-gamma/IL-10 double-positive regulatory type 1 cells emerged during T helper type 1 differentiation of old T helper cells in presence of rapamycin. Similarly, CD4(+) IFN-gamma(+) IL-10(+) cells expanded among Foxp3-negative cells after in vivo treatment of old recipients with rapamycin. Conclusions. Our results highlight novel aspects of age-dependent immunosuppressive effects of rapamycin, with relevance for age-specific immunosuppressive regimens.

Cases of primary non-Hodgkin’s lymphoma of the prostate are globally rare. The present study reports a case of prostatic diffuse large B-cell lymphoma (DLBCL) with intractable hematuria in a 75-year-old male. The patient presented with difficulties in urination and gross hematuria. A prostate biopsy was performed immediately, followed by conservative treatment for bleeding. A bilateral iliac arteriography and chemoembolization were then performed as emergency procedures under local anesthesia due to significant bleeding and a sharply decreased blood pressure, indicating the failure of the conservative treatment. Consequently, the bleeding was effectively controlled. Pathological examination of the prostate biopsy confirmed the presence of a DLBCL of non-germinal center B-cell origin. Immunohistochemical examination demonstrated cluster of differentiation (CD)20(++), CD3(+), leukocyte common antigen(+++), B-cell lymphoma-2(+) and prostate-specific antigen(−) results. Due to the poor general condition and low hemoglobin levels of the patient, a low-dose Rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy regimen was administered. Subsequent to three courses of chemotherapy, the patient achieved complete remission. In conclusion, combining R-CHOP and bilateral selective iliac arterial chemoembolization could be a safe and effective way to treat patients with non-Hodgkin’s lymphoma of the prostate and intractable hematuria.

Summary Although testosterone replacement therapy can restore serum testosterone concentrations to normal level in late-onset hypogonadism patients, whether it can improve patients' quality of life remains uncertain. Therefore, we perform a meta-analysis of randomized controlled trials on this issue. Five randomized controlled trials total 1,212 patients were included. Fixed-effect model was used to calculate the weighted mean difference of score of Aging Males' Symptom rating scale. Our result reveals that testosterone replacement therapy improves patients' health-related quality of life in terms of the decrease in the AMS total score [WMD = −2.96 (−4.21, −1.71), p