INPP5K controls the dynamic structure and signaling of wild-type and mutated, leukemia-associated IL-7 receptors.

The downstream signaling of the interleukin-7 (IL-7) receptor (IL-7R) plays important physiological and pathological roles, including the differentiation of lymphoid cells and proliferation of acute lymphoblastic leukemia cells. Gain-of-function mutations in the IL-7Rα chain, the specific component of the receptor for IL-7, result in constitutive, IL-7-independent signaling and trigger acute lymphoblastic leukemia. Here, we show that the loss of the phosphoinositide 5-phosphatase INPP5K is associated with increased levels of the INPP5K substrate phosphatidylinositol 4,5-bisphosphate (PtdIns[4,5]P2) and causes an altered dynamic structure of the IL-7 receptor. We discovered that the IL-7Rα chain contains a very conserved positively charged polybasic amino acid sequence in its cytoplasmic juxtamembrane region; this region establish stronger ionic interactions with negatively charged PtdIns(4,5)P2 in the absence of INPP5K, freezing the IL-7Rα chain structure. This dynamic structural alteration causes defects in IL-7R signaling, culminating in decreased expressions of EBF1 and PAX5 transcription factors, in microdomain formation, cytoskeletal reorganization, and bone marrow B-cell differentiation. Similar alterations after the reduced INPP5K expression also affected mutated, constitutively activated IL-7Rα chains that trigger leukemia development, leading to reduced cell proliferation. Altogether, our results indicate that the lipid 5-phosphatase INPP5K hydrolyzes PtdIns(4,5)P2, allowing the requisite conformational changes of the IL-7Rα chain for optimal signaling.

Profibrotic Role of Inducible Heat Shock Protein 90α Isoform in Systemic Sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease that affects skin and multiple internal organs. TGF-ß, a central trigger of cutaneous fibrosis, activates fibroblasts with the involvement of the stress-inducible chaperone heat shock protein 90 isoform α (Hsp90α). Available evidence supports overexpression and secretion of Hsp90α as a feature in profibrotic pathological conditions. The aim of this work is to investigate the expression and function of Hsp90α in experimental models of skin fibrosis such as human fibroblasts, C57BL/6 mice, and in human SSc. For this purpose, we generated a new experimental model based on doxorubicin administration with improved characteristics with respect to the bleomycin model. We visualized disease progression in vivo by fluorescence imaging. In this work, we obtained Hsp90α mRNA overexpression in human skin fibroblasts, in bleomycin- and doxorubicin-induced mouse fibrotic skin, and in lungs of bleomycin- and doxorubicin-treated mice. Hsp90α-deficient mice showed significantly decreased skin thickness compared with wild-type mice in both animal models. In SSc patients, serum Hsp90α levels were increased in patients with lung involvement and in patients with the diffuse form of SSc (dSSc) compared with patients with the limited form of SSc. The serum Hsp90α levels of patients dSSc were correlated with the Rodnan score and the forced vital capacity variable. These results provide new supportive evidence of the contribution of the Hsp90α isoform in the development of skin fibrosis. In SSc, these results indicated that higher serum levels were associated with dSSc and lung fibrosis.

Low-Cost Prototype to Automate the 3D Digitization of Pieces: An Application Example and Comparison.

This work is aimed at describing the design of a mechanical and programmable 3D capturing system to be used by either 3D scanner or DSLR camera through photogrammetry. Both methods are widely used in diverse areas, from engineering, architecture or archaeology, up to the field of medicine; but they also entail certain disadvantages, such as the high costs of certain equipment, such as scanners with some precision, and the need to resort to specialized operatives, among others. The purpose of this design is to create a robust, precise and cost-effective system that improves the limitations of the present equipment on the market, such as robotic arms or rotary tables. For this reason, a preliminary study has been conducted to analyse the needs of improvement, later, we have focused on the 3D design and prototyping. For its construction, there have been used the FDM additive technology and structural components that are easy to find in the market. With regards to electronic components, basic electronics and Arduino-based 3D printers firmware have been selected. For system testing, the capture equipment consists of a Spider Artec 3D Scanner and a Nikon 5100 SLR Camera. Finally, 3D models have been developed by comparing the 3D meshes obtained by the two methods, obtaining satisfactory results.

Anti-IL17 treatment ameliorates Down syndrome phenotypes in mice.

Down syndrome (DS) is characterized by structural and functional anomalies that are present prenatally and that lead to intellectual disabilities. Later in life, the cognitive abilities of DS individuals progressively deteriorate due to the development of Alzheimer's disease (AD)-associated neuropathology (i.e., ß-amyloid (Aß) plaques, neurofibrillary tangles (NFTs), neurodegeneration, synaptic pathology, neuroinflammation and increased oxidative stress). Increasing evidence has shown that among these pathological processes, neuroinflammation plays a predominant role in AD etiopathology. In AD mouse models, increased neuroinflammation appears earlier than Aß plaques and NFTs, and in DS and AD models, neuroinflammation exacerbates the levels of soluble and insoluble Aß species, favoring neurodegeneration. The Ts65Dn (TS) mouse, the most commonly used murine model of DS, recapitulates many alterations present in both DS and AD individuals, including enhanced neuroinflammation. In this study, we observed an altered neuroinflammatory milieu in the hippocampus of the TS mouse model. Pro-inflammatory mediators that were elevated in the hippocampus of this model included pro-inflammatory cytokine IL17A, which has a fundamental role in mediating brain damage in neuroinflammatory processes. Here, we analyzed the ability of an anti-IL17A antibody to reduce the neuropathological alterations that are present in TS mice during early neurodevelopmental stages (i.e., hippocampal neurogenesis and hypocellularity) or that are aggravated in later-life stages (i.e., cognitive abilities, cholinergic neuronal loss and increased cellular senescence, APP expression, Aß peptide expression and neuroinflammation). Administration of anti-IL17 for 5 months, starting at the age of 7 months, partially improved the cognitive abilities of the TS mice, reduced the expression of several pro-inflammatory cytokines and the density of activated microglia and normalized the APP and Aß1-42 levels in the hippocampi of the TS mice. These results suggest that IL17-mediated neuroinflammation is involved in several AD phenotypes in TS mice and provide a new therapeutic target to reduce these pathological characteristics.

Map3k8 Modulates Monocyte State and Atherogenesis in ApoE-/- Mice.

OBJECTIVE: Map3k8 (Cot/Tpl2) activates the MKK1/2-ERK1/2, MAPK pathway downstream from interleukin-1R, tumor necrosis factor-αR, NOD-2R (nucleotide-binding oligomerization domain-like 2R), adiponectinR, and Toll-like receptors. Map3k8 plays a key role in innate and adaptive immunity and influences inflammatory processes by modulating the functions of different cell types. However, its role in atherogenesis remains unknown. In this study, we analyzed the role of this kinase in this pathology. APPROACH AND RESULTS: We show here that Map3k8 deficiency results in smaller numbers of Ly6ChighCD11clow and Ly6ClowCD11chigh monocytes in ApoE-/- mice fed a high-fat diet (HFD). Map3k8-/-ApoE-/- monocytes displayed high rates of apoptosis and reduced amounts of Nr4a1, a transcription factor known to modulate apoptosis in Ly6ClowCD11chigh monocytes. Map3k8-/-ApoE-/- splenocytes and macrophages showed irregular patterns of cytokine and chemokine expression. Map3k8 deficiency altered cell adhesion and migration in vivo and decreased CCR2 expression, a determinant chemokine receptor for monocyte mobilization, on circulating Ly6ChighCD11clow monocytes. Map3k8-/-ApoE-/- mice fed an HFD showed decreased cellular infiltration in the atherosclerotic plaque, with low lipid content. Lesions had similar size after Map3k8+/+ApoE-/- bone marrow transplant into Map3k8-/-ApoE-/- and Map3k8+/+ApoE-/- mice fed an HFD, whereas smaller plaques were observed after the transplantation of bone marrow lacking both ApoE and Map3k8. CONCLUSIONS: Map3k8 decreases apoptosis of monocytes and enhances CCR2 expression on Ly6ChighCD11clow monocytes of ApoE-/- mice fed an HFD. These findings explain the smaller aortic lesions in ApoE-/- mice with Map3k8-/-ApoE-/- bone marrow cells fed an HFD, supporting further studies of Map3k8 as an antiatherosclerotic target.

TGFß Superfamily Members as Regulators of B Cell Development and Function-Implications for Autoimmunity.

The TGFß superfamily is composed of more than 33 growth and differentiation factors, including TGFß1, ß2, ß3, BMPs, GDFs, nodal-related proteins, and activins. These members usually exert pleiotropic actions on several tissues and control multiple cellular processes, such as cell growth, cell survival, cell migration, cell fate specification, and differentiation, both during embryonic development and postnatal life. Although the effects of these factors on immune responses were elucidated long ago, most studies have been focused on the actions of TGFßs on T cells, as major regulators of adaptive immunity. In this review, we discuss new findings about the involvement of TGFß superfamily members in the control of B cell development and function. Moreover, the potential contribution of TGFß signaling to control B cell-mediated autoimmune diseases and its utility in the design of new therapies are also discussed.

Context-dependent regulation of Th17-associated genes and IFNγ expression by the transcription factor NFAT5.

Stress-activated transcription factors influence T-cell function in different physiopathologic contexts. NFAT5, a relative of nuclear factor κB and the calcineurin-activated NFATc transcription factors, protects mammalian cells from hyperosmotic stress caused by the elevation of extracellular sodium levels. In T cells exposed to hypernatremia, NFAT5 not only induces osmoprotective gene products but also cytokines and immune receptors, which raises the question of whether this factor could regulate other T-cell functions in osmostress-independent contexts. Here we have used mice with a conditional deletion of Nfat5 in mature T lymphocytes to explore osmostress-dependent and -independent functions of this factor. In vitro experiments with CD4 T cells stimulated in hyperosmotic medium showed that NFAT5 enhanced the expression of IL-2 and the Th17-associated gene products RORγt and IL-23R. By contrast, NFAT5-deficient CD4 T cells activated in vivo by anti-CD3 antibody exhibited a different activation profile and were skewed towards enhanced interferon γ (IFNγ) and IL-17 expression and attenuated Treg responses. Using a model of experimental colitis, we observed that mice lacking NFAT5 in T cells exhibited exacerbated intestinal colitis and enhanced expression of IFNγ in draining lymph nodes and colon. These results show that NFAT5 can modulate different T-cell responses depending on stress conditions and stimulatory context.

Distinct serum proteome profiles associated with collagen-induced arthritis and complete Freund's adjuvant-induced inflammation in CD38⁻/⁻ mice: The discriminative power of protein species or proteoforms.

Collagen-type-II-induced arthritis (CIA) is an autoimmune disease, which involves a complex host systemic response including inflammatory and autoimmune reactions. CIA is milder in CD38(-/-) than in wild-type (WT) mice. ProteoMiner-equalized serum samples were subjected to 2D-DiGE and MS-MALDI-TOF/TOF analyses to identify proteins that changed in their relative abundances in CD38(-/-) versus WT mice either with arthritis (CIA(+) ), with no arthritis (CIA(-) ), or with inflammation (complete Freund's adjuvant (CFA)-treated mice). Multivariate analyses revealed that a multiprotein signature (n = 28) was able to discriminate CIA(+) from CIA(-) mice, and WT from CD38(-/-) mice within each condition. Likewise, a distinct multiprotein signature (n = 16) was identified which differentiated CIA(+) CD38(-/-) mice from CIA(+) WT mice, and lastly, a third multiprotein signature (n = 18) indicated that CD38(-/-) and WT mice could be segregated in response to CFA treatment. Further analyses showed that the discriminative power to distinguish these groups was reached at protein species level and not at the protein level. Hence, the need to identify and quantify proteins at protein species level to better correlate proteome changes with disease processes. It is crucial for plasma proteomics at the low-abundance protein species level to apply the ProteoMiner enrichment. All MS data have been deposited in the ProteomeXchange with identifiers PXD001788, PXD001799 and PXD002071 (http://proteomecentral.proteomexchange.org/dataset/PXD001788, http://proteomecentral.proteomexchange.org/dataset/PXD001799 and http://proteomecentral.proteomexchange.org/dataset/PXD002071).

p27(Kip1) inhibits systemic autoimmunity through the control of Treg cell activity and differentiation.

OBJECTIVE: Despite the importance of Treg cells in the maintenance of immunologic tolerance, the mechanisms that control their generation and activity are unknown. Since the cell cycle inhibitor p27(Kip1) (p27) was involved in T cell anergy, we undertook this study to explore its role in both Treg cell processes. METHODS: The development of type II collagen-induced arthritis (CIA) and lupus-like abnormalities was compared between transgenic mice overexpressing human Bcl-2 in T cells (BCL2-TgT mice) and nontransgenic mice that were deficient or not deficient in p27. The contribution of Treg cells to disease evolution was also explored. Finally, the in vitro activity of Treg cells and their differentiation from naive CD4+ cells was compared between these strains of mice. RESULTS: BCL2-TgT mice were protected against CIA by a Treg cell-dependent mechanism. In association with this protection, the overexpression of Bcl-2 in T cells enhanced the differentiation and activity of Treg cells. Both Bcl-2 effects were independent of its antiapoptotic activity but dependent on its capacity to induce the expression of p27 that augmented the strength of transforming growth factor ß (TGFß) signaling in T cells. Accordingly, down-modulation of p27 expression in BCL2-TgT mice promoted CIA. In addition, p27 deficiency in aged C57BL/6 mice reduced the number and activity of Treg cells and induced the development of mild lupus-like abnormalities. CONCLUSION: Our results point to p27 as a critical regulator of Treg cell differentiation and function through the positive modulation of TGFß signaling strength in T cells.

MYC directly transactivates CR2/CD21, the receptor of the Epstein-Barr virus, enhancing the viral infection of Burkitt lymphoma cells.

MYC is an oncogenic transcription factor dysregulated in about half of total human tumors. While transcriptomic studies reveal more than 1000 genes regulated by MYC, a much smaller fraction of genes is directly transactivated by MYC. Virtually all Burkitt lymphoma (BL) carry chromosomal translocations involving MYC oncogene. Most endemic BL and a fraction of sporadic BL are associated with Epstein-Barr virus (EBV) infection. The currently accepted mechanism is that EBV is the BL-causing agent inducing MYC translocation. Herein we show that the EBV receptor, CR2 (also called CD21), is a direct MYC target gene. This is based on several pieces of evidence: MYC induces CR2 expression in both proliferating and arrested cells and in the absence of protein synthesis, binds the CR2 promoter and transactivates CR2 in an E-box-dependent manner. Moreover, using mice with conditional MYC ablation we show that MYC induces CR2 in primary B cells. Importantly, modulation of MYC levels directly correlates with EBV's ability of infection in BL cells. Altogether, in contrast to the widely accepted hypothesis for the correlation between EBV and BL, we propose an alternative hypothesis in which MYC dysregulation could be the first event leading to the subsequent EBV infection.

Exacerbation of type II collagen-induced arthritis in apolipoprotein E-deficient mice in association with the expansion of Th1 and Th17 cells.

OBJECTIVE: To explore the bidirectional relationship between the development of rheumatoid arthritis (RA) and atherosclerosis using bovine type II collagen (CII)-immunized B10.RIII apoE(-/-) mice, a murine model of spontaneous atherosclerosis and collagen-induced arthritis (CIA). METHODS: Male B10.RIII apoE(-/-) mice and wild-type controls were immunized with 150 µg of CII emulsified in Freund's complete adjuvant (CFA). The clinical, radiologic, and histopathologic severity of CIA, the levels of circulating IgG1 and IgG2a anti-CII antibodies, the expression of proinflammatory and antiinflammatory cytokines in the joints, and the percentages of Th1, Th17, and Treg lymphocytes in the draining lymph nodes were evaluated during CIA induction. In addition, the size of atherosclerotic lesions was assessed in these mice 8 weeks after CIA induction. RESULTS: B10.RIII apoE(-/-) mice that were immunized with CII and CFA developed an exacerbated CIA that was accompanied by increased joint expression of multiple proinflammatory cytokines and by the expansion in the draining lymph nodes of Th1 and Th17 cells. In contrast, the size of vascular lesions in B10.RIII apoE(-/-) mice was not affected by the development of CIA. CONCLUSION: Our findings indicate that a deficiency in apolipoprotein E and/or its consequences in cholesterol metabolism act as accelerating factors in autoimmunity by promoting Th1 and Th17 inflammatory responses.

[Management of prostate cancer biochemical recurrence in the clinical guidelines]. / Manejo de la recidiva bioquímica en el cáncer de próstata según las guías de práctica clínica.

OBJECTIVE: Review of the Guidelines which have major impact on the urological field, in order to compare and to know their recommendations in the diagnosis and management of biochemical relapse after a healing treatment of prostate cancer (radical prostatectomy or radiotherapy). METHODS: We review the Guidelines of the European Urological Association (EAU), the American Urological Association (AUA), of the National Comprehensive Cancer Network (NCCN) and those of the National Institute for Health and Clinical Excellence (NICE), as well as the scientific evidence on which they are based. RESULTS: In this paper we state the complexity of the subject being dealt with and coincidences and differences among them. The definition of relapse varies depending on whether the patient has undergone either radical prostatectomy or radiotherapy. Regarding treatment, in the first case early radiotherapy is the treatment of choice, but recommendations after radiotherapy are not so specific. CONCLUSION: Clinical Guidelines represent a great aid in decision making for the professional. Guidelines give recommendations with a higher o lower degree of scientific evidence and must be evaluated regularly to include new evidences which are coming through.

Oncofid-P-B: a novel treatment for BCG unresponsive carcinoma in situ (CIS) of the bladder: Results of a prospective European Multicentre study at 15 months from treatment start.

PURPOSE: This study reports the safety and efficacy of Oncofid-P-B, a novel compound under development by Fidia Farmaceutici S.p.A. with specific binding to CD44 receptor, in patients with CIS unresponsive or intolerant to BCG. MATERIALS AND METHODS: This is a phase 1 open-label, single arm, multicenter European study to assess safety, tolerability and efficacy of Oncofid-P-B administered in 20 patients with CIS ± Ta-T1, unresponsive or intolerant to BCG, unwilling or unfit for cystectomy. Oncofid-P-B was administered by intravesical instillation for 12 consecutive weeks (intensive phase) followed, in CR patients, by 12 monthly instillations (maintenance phase). The primary objective was the overall safety profile. Secondary objectives included: i) any evidence of antitumor activity, ii) patient's compliance, iii) systemic absorption. The CR was defined as a negative cystoscopy, negative biopsy of the urothelium and negative cytology. RESULTS: At the end of the intensive phase, 15 of the 20 enrolled patients (75%), achieved the CR. Patients still in CR after 3, 6, 9 and 12 months of maintenance phase were 13 (65%), 12 (60%), 9 (45%) and 8 (40%), respectively. Only seven (5 mild and 2 moderate) drug-related AEs were reported in three patients. No drug related serious AEs and no drug related withdrawals have been reported. In all plasma samples, the drug concentratiosn was below the LLOQ (1ng/ml). CONCLUSIONS: Oncofid-P-B is very safe, well tolerated and highly effective (75% CR) when administered weekly for up to 12 consecutive weeks (75% CR), with 40% CR still after 15 months from treatment start.

Extracellular vesicles from pristane-treated CD38-deficient mice express an anti-inflammatory neutrophil protein signature, which reflects the mild lupus severity elicited in these mice.

In CD38-deficient ( Cd38-/- ) mice intraperitoneal injection of pristane induces a lupus-like disease, which is milder than that induced in WT mice, showing significant differences in the inflammatory and autoimmune processes triggered by pristane. Extracellular vesicles (EV) are present in all body fluids. Shed by cells, their molecular make-up reflects that of their cell of origin and/or tissue pathological situation. The aim of this study was to analyze the protein composition, protein abundance, and functional clustering of EV released by peritoneal exudate cells (PECs) in the pristane experimental lupus model, to identify predictive or diagnostic biomarkers that might discriminate the autoimmune process in lupus from inflammatory reactions and/or normal physiological processes. In this study, thanks to an extensive proteomic analysis and powerful bioinformatics software, distinct EV subtypes were identified in the peritoneal exudates of pristane-treated mice: 1) small EV enriched in the tetraspanin CD63 and CD9, which are likely of exosomal origin; 2) small EV enriched in CD47 and CD9, which are also enriched in plasma-membrane, membrane-associated proteins, with an ectosomal origin; 3) small EV enriched in keratins, ECM proteins, complement/coagulation proteins, fibrin clot formation proteins, and endopetidase inhibitor proteins. This enrichment may have an inflammation-mediated mesothelial-to-mesenchymal transition origin, representing a protein corona on the surface of peritoneal exudate EV; 4) HDL-enriched lipoprotein particles. Quantitative proteomic analysis allowed us to identify an anti-inflammatory, Annexin A1-enriched pro-resolving, neutrophil protein signature, which was more prominent in EV from pristane-treated Cd38-/- mice, and quantitative differences in the protein cargo of the ECM-enriched EV from Cd38-/- vs WT mice. These differences are likely to be related with the distinct inflammatory outcome shown by Cd38-/- vs WT mice in response to pristane treatment. Our results demonstrate the power of a hypothesis-free and data-driven approach to transform the heterogeneity of the peritoneal exudate EV from pristane-treated mice in valuable information about the relative proportion of different EV in a given sample and to identify potential protein markers specific for the different small EV subtypes, in particular those proteins defining EV involved in the resolution phase of chronic inflammation.

BAMBI (bone morphogenetic protein and activin membrane-bound inhibitor) reveals the involvement of the transforming growth factor-beta family in pain modulation.

Transforming growth factors-beta (TGF-betas) signal through type I and type II serine-threonine kinase receptor complexes. During ligand binding, type II receptors recruit and phosphorylate type I receptors, triggering downstream signaling. BAMBI [bone morphogenetic protein (BMP) and activin membrane-bound inhibitor] is a transmembrane pseudoreceptor structurally similar to type I receptors but lacks the intracellular kinase domain. BAMBI modulates negatively pan-TGF-beta family signaling; therefore, it can be used as an instrument for unraveling the roles of these cytokines in the adult CNS. BAMBI is expressed in regions of the CNS involved in pain transmission and modulation. The lack of BAMBI in mutant mice resulted in increased levels of TGF-beta signaling activity, which was associated with attenuation of acute pain behaviors, regardless of the modality of the stimuli (thermal, mechanical, chemical/inflammatory). The nociceptive hyposensitivity exhibited by BAMBI(-/-) mice was reversed by the opioid antagonist naloxone. Moreover, in a model of chronic neuropathic pain, the allodynic responses of BAMBI(-/-) mice also appeared attenuated through a mechanism involving delta-opioid receptor signaling. Basal mRNA and protein levels of precursor proteins of the endogenous opioid peptides proopiomelanocortin (POMC) and proenkephalin (PENK) appeared increased in the spinal cords of BAMBI(-/-). Transcript levels of TGF-betas and their intracellular effectors correlated directly with genes encoding opioid peptides, whereas BAMBI correlated inversely. Furthermore, incubation of spinal cord explants with activin A or BMP-7 increased POMC and/or PENK mRNA levels. Our findings identify TGF-beta family members as modulators of acute and chronic pain perception through the transcriptional regulation of genes encoding the endogenous opioids.

GITR contributes to the systemic adjuvanticity of the Escherichia coli heat-labile enterotoxin.

The Escherichia coli heat-labile enterotoxin (LT) possesses a powerful mucosal and systemic adjuvant effect. However, little is known about the cellular and molecular basis of the immunostimulatory activity of LT at the mucosal level, and even less information is available on the mechanisms underlying its systemic adjuvant activity. In this study, we show that distinct mechanisms are responsible for the parenteral and mucosal adjuvanticity of LT. Indeed, the systemic administration of LT upregulates the expression of glucocorticoid-induced TNFR-related protein (GITR), but not other activation markers, in naive T cells. Using WT and GITR-deficient mice and LT and its enzymatically inactive mutant LTK63 as adjuvants, we show that the induction of GITR expression in T cells accounts for the systemic immunostimulatory capacity of LT, which requires an intact enzymatic activity. In contrast, the mucosal administration of LT does not induce GITR expression on Peyer's patche T cells and accordingly no differences are observed in the mucosal adjuvanticity of LT between WT and GITR-deficient mice. Altogether, our results demonstrate the distinct effect of LT after parenteral administration when compared with the mucosal delivery, and describe a new mechanism of LT adjuvanticity related to its ability to induce the expression of GITR in CD4(+) T cells.

Cadaver donor kidney retransplantation in the pediatric patient: complications and long-term outcome.

PURPOSE: We compared the outcome of second and third kidney allografts with that of the first kidney allograft in pediatric recipients. MATERIALS AND METHODS: We classified 173 cadaveric kidney recipients into 2 groups. Group 1 comprised 120 first transplants and group 2 comprised 53 retransplants, including 43 second and 10 third transplants. We compared demographic characteristics and survival in groups 1 and 2. RESULTS: Group 1 consisted of 78 boys and 42 girls with a mean ± SD age of 11.5 ± 4.2 years. Group 2 consisted of 37 boys and 16 girls with a mean age of 10.4 ± 4.7 years. One, 5, 10 and 15-year graft survival rates were 78.7%, 64.3%, 54.5% and 50.7% for first transplants vs 82.8%, 57.8%, 57.8% and 41.3%, respectively, for retransplants (p = 0.757). Patient survival at 1, 5 and 15-year was 95.8%, 89.6%, 84.9% in the first transplant group vs 93.6%, 93.6% and 93.6%, respectively, in the retransplant group (p = 0.0.63). Graft survival was significantly higher in patients who did vs did not receive calcineurin inhibitors in the 2 groups (p = 0.02). CONCLUSIONS: Kidney retransplantation in the pediatric population can yield excellent long-term outcomes, especially in patients treated with calcineurin inhibitors.

CD38 Deficiency Ameliorates Chronic Graft-Versus-Host Disease Murine Lupus via a B-Cell-Dependent Mechanism.

The absence of the mouse cell surface receptor CD38 in Cd38-/- mice suggests that this receptor acts as a positive regulator of inflammatory and autoimmune responses. Here, we report that, in the context of the chronic graft-versus-host disease (cGVHD) lupus inducible model, the transfer of B6.C-H2bm12/KhEg(bm12) spleen cells into co-isogenic Cd38-/- B6 mice causes milder lupus-like autoimmunity with lower levels of anti-ssDNA autoantibodies than the transfer of bm12 spleen cells into WT B6 mice. In addition, significantly lower percentages of Tfh cells, as well as GC B cells, plasma cells, and T-bet+CD11chi B cells, were observed in Cd38-/- mice than in WT mice, while the expansion of Treg cells and Tfr cells was normal, suggesting that the ability of Cd38-/- B cells to respond to allogeneic help from bm12 CD4+ T cells is greatly diminished. The frequencies of T-bet+CD11chi B cells, which are considered the precursors of the autoantibody-secreting cells, correlate with anti-ssDNA autoantibody serum levels, IL-27, and sCD40L. Proteomics profiling of the spleens from WT cGVHD mice reflects a STAT1-driven type I IFN signature, which is absent in Cd38-/- cGVHD mice. Kidney, spleen, and liver inflammation was mild and resolved faster in Cd38-/- cGVHD mice than in WT cGVHD mice. We conclude that CD38 in B cells functions as a modulator receptor that controls autoimmune responses.

Involvement of the intrinsic and extrinsic cell-death pathways in the induction of apoptosis of mature lymphocytes by the Escherichia coli heat-labile enterotoxin.

Escherichia coli heat-labile enterotoxin (LT) exhibits a broad range of immunomodulatory activities, including the induction of lymphocyte-programmed cell death. In previous studies, we have demonstrated that in vivo LT promotes apoptosis of immature T and B cells through the stimulation of endogenous glucocorticoids. In the present study, we show that the extrinsic cell-death pathway as well as the apoptosis-inducing factor do not participate in the LT-induced elimination of thymocytes. In contrast to developing lymphocytes, LT promotes the death of mature lymphocytes by both glucocorticoid- and Fas death receptor/Fas ligand-dependent mechanisms. However, the dependency of these mechanisms in the LT-induced cell-death activity seems to be different among CD4(+) and CD8(+) T cells. Altogether, our study shows that the same bacterial toxin can induce apoptosis of lymphoid cells through several mechanisms depending on the status of differentiation of these cells.

B-cell overexpression of Bcl-2 cooperates with p21 deficiency for the induction of autoimmunity and lymphomas.

Genetic abnormalities predisposing to autoimmunity generally act in a cooperative manner affecting one or several mechanisms regulating immunological tolerance. In addition, many of these genetic abnormalities are also involved in the development of lymphoproliferative diseases. In the present study, we have determined the possible cooperation between deficiencies in members of the Cip/Kip family of cell cycle regulators (p21(WAF1/Cip1) or p27(kip1)) and the overexpression of human Bcl-2 in B lymphocytes in the induction of autoimmune and lymphoproliferative diseases in non-autoimmune C57BL/6 (B6) mice. Unlike single mutant mice, B6.p21(-/-) mice transgenic for human Bcl-2 in B cells developed a lethal autoimmune syndrome characterized by the production of autoantibodies, the prominent expansion of memory B and CD4(+) T cells and the development of severe glomerular lesions resembling IgA nephropathy. Furthermore, these mice presented a high incidence of B-cell lymphoproliferative disorders. Such genetic cooperation in the induction of autoimmunity was not observed in B6.p27(-/-) mice transgenic for human Bcl-2 in B cells. Altogether, what we have demonstrated here is the existence of preferential interactions among particular regulators of the G(1)/S transition of the cell cycle and B-cell survival in the induction of systemic autoimmune and lymphoproliferative diseases.