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The expression of BTB-ZF transcription factors such as ThPOK in CD4+ T cells, Bcl6 in T follicular helper cells, and PLZF in natural killer T cells defines the fundamental nature and characteristics of these cells. Screening for lineage-defining BTB-ZF genes led to the discovery of a subset of T cells that expressed Zbtb20. About half of Zbtb20+ T cells expressed FoxP3, the lineage-defining transcription factor for regulatory T cells (Tregs). Zbtb20+ Tregs were phenotypically and genetically distinct from the larger conventional Treg population. Zbtb20+ Tregs constitutively expressed mRNA for interleukin-10 and produced high levels of the cytokine upon primary activation. Zbtb20+ Tregs were enriched in the intestine and specifically expanded when inflammation was induced by the use of dextran sodium sulfate. Conditional deletion of Zbtb20 in T cells resulted in a loss of intestinal epithelial barrier integrity. Consequently, knockout (KO) mice were acutely sensitive to colitis and often died because of the disease. Adoptive transfer of Zbtb20+ Tregs protected the Zbtb20 conditional KO mice from severe colitis and death, whereas non-Zbtb20 Tregs did not. Zbtb20 was detected in CD24hi double-positive and CD62Llo CD4 single-positive thymocytes, suggesting that expression of the transcription factor and the phenotype of these cells were induced during thymic development. However, Zbtb20 expression was not induced in "conventional" Tregs by activation in vitro or in vivo. Thus, Zbtb20 expression identified and controlled the function of a distinct subset of Tregs that are involved in intestinal homeostasis. Zbtb20+ Tregs inhibit colitis: BTB-ZF transcription factors play numerous roles in immune cell regulation. Here, Krzyzanowska et al. studied the BTB-ZF transcription factor Zbtb20 and its role in regulatory T cells (Tregs) using various knockout mouse models and colitis models. They found that Zbtb20 expressing Tregs were a unique subset that expressed very high levels of IL-10. These Tregs were found in the intestine and played a role in protecting the intestine from colitis-induced damage in a Zbtb20- and IL-10–mediated manner. Thus, the authors have identified a subset of Tregs expressing Zbtb20 that seem to be highly suppressive and important for intestinal homeostasis. [ABSTRACT FROM AUTHOR]

Much emphasis has been placed on participant's psychological safety within genomic research studies; however, few studies have addressed parental psychological health effects associated with their child's participation in genomic studies, particularly when parents meet the threshold for clinical concern for depression. We aimed to determine if parents' depressive symptoms were associated with their child's participation in a randomized‐controlled trial of newborn exome sequencing. Parents completed the Edinburgh Postnatal Depression Scale (EPDS) at baseline, immediately post‐disclosure, and 3 months post‐disclosure. Mothers and fathers scoring at or above thresholds for clinical concern on the EPDS, 12 and 10, respectively, indicating possible Major Depressive Disorder with Peripartum Onset, were contacted by study staff for mental health screening. Parental concerns identified in follow‐up conversations were coded for themes. Forty‐five parents had EPDS scores above the clinical threshold at baseline, which decreased by an average of 2.9 points immediately post‐disclosure and another 1.1 points 3 months post‐disclosure (both p ≤.014). For 28 parents, EPDS scores were below the threshold for clinical concern at baseline, increased by an average of 4.7 points into the elevated range immediately post‐disclosure, and decreased by 3.8 points at 3 months post‐disclosure (both p <.001). Nine parents scored above thresholds only at 3 months post‐disclosure after increasing an average of 5.7 points from immediately post‐disclosure (p <.001). Of the 82 parents who scored above the threshold at any time point, 43 (52.4%) were reached and 30 (69.7%) of these 43 parents attributed their elevated scores to parenting stress, balancing work and family responsibilities, and/or child health concerns. Only three parents (7.0%) raised concerns about their participation in the trial, particularly their randomization to the control arm. Elevated scores on the EPDS were typically transient and parents attributed their symptomatology to life stressors in the postpartum period rather than participation in a trial of newborn exome sequencing. [ABSTRACT FROM AUTHOR]

Viral and parasitic coinfections are known to lead to both enhanced disease progression and altered disease states. HTLV-1 and Strongyloides stercoralis are co-endemic throughout much of their worldwide ranges resulting in a significant incidence of coinfection. Independently, HTLV-1 induces a Th1 response and S. stercoralis infection induces a Th2 response. However, coinfection with the two pathogens has been associated with the development of S. stercoralis hyperinfection and an alteration of the Th1/Th2 balance. In this study, a model of HTLV-1 and S. stercoralis coinfection in CD34+ umbilical cord blood hematopoietic stem cell engrafted humanized mice was established. An increased level of mortality was observed in the HTLV-1 and coinfected animals when compared to the S. stercoralis infected group. The mortality was not correlated with proviral loads or total viral RNA. Analysis of cytokine profiles showed a distinct shift towards Th1 responses in HTLV-1 infected animals, a shift towards Th2 cytokines in S. stercoralis infected animals and elevated TNF-α responses in coinfected animals. HTLV-1 infected and coinfection groups showed a significant, yet non-clonal expansion of the CD4+CD25+ T-cell population. Numbers of worms in the coinfection group did not differ from those of the S. stercoralis infected group and no autoinfective larvae were found. However, infective larvae recovered from the coinfection group showed an enhancement in growth, as was seen in mice with S. stercoralis hyperinfection caused by treatment with steroids. Humanized mice coinfected with S. stercoralis and HTLV-1 demonstrate features associated with human infection with these pathogens and provide a unique opportunity to study the interaction between these two infections in vivo in the context of human immune cells. Author summary: Human infections with the virus HTLV-1 and the nematode Strongyloides stercoralis are co-endemic throughout much of their worldwide ranges resulting in a significant incidence of coinfection. The coincident infections result in S. stercoralis hyperinfection and an alteration of the balance of the immune responses to the virus and to the worm. In this study, a novel model of HTLV-1 and S. stercoralis coinfection was established in humanized mice. Mortality was increased in the HTLV-1 and coinfected animals as compared to the S. stercoralis infected group. Analysis of cytokine profiles showed a distinct shift towards Th1 responses in HTLV-1 infected animals, a shift towards Th2 cytokines in S. stercoralis infected animals and elevated TNF-α responses in coinfected animals. Numbers of worms in the coinfection group did not differ from those of the S. stercoralis infected group, however, infective larvae recovered from the coinfection group showed a significant enhancement in growth. Humanized mice coinfected with S. stercoralis and HTLV-1 demonstrate features associated with human infection with these pathogens and provide a unique opportunity to study the interaction between these two infections. [ABSTRACT FROM AUTHOR]

The article discusses a randomized phase-two study which determines whether changes in nuclear factor kappa B (NF-ƘB) activity corresponded with changes in the expression of NF-ƘB target genes. In the said study, the newly diagnosed patients with acute myelogenous leukemia (AML) eligible for standard induction chemotherapy were assigned to choline magnesium trisalicylate (CMT) or no CMT.

Summary Osteoblasts and adipocytes are derived from a common precursor, mesenchymal stem cells (MSCs). Alterations in the normal fate of differentiating MSCs are involved in the development of obesity and osteoporosis. Here, we report that viable motheaten ( me v ) mice, which are deficient in the SH2-domain-containing phosphatase-1 (SHP1), develop osteoporosis spontaneously. Consistently, MSCs from me v /me v mice exhibit significantly reduced osteogenic potential and greatly increased adipogenic potential. When MSCs were transplanted into nude mice, SHP1-deficient MSCs resulted in diminished bone formation compared with wild-type MSCs. SHP1 was found to bind to GSK3β and suppress its kinase activity by dephosphorylating pY216, thus resulting in β-catenin stabilization. Mice, in which SHP1 was deleted in MSCs using SHP1 fl/fl Dermo1-cre, displayed significantly decreased bone mass and increased adipose tissue. Taken together, these results suggest a possible role for SHP1 in controlling tissue homeostasis through modulation of MSC differentiation via Wnt signaling regulation. [ABSTRACT FROM AUTHOR]

An imbalance between normal adipogenesis and osteogenesis by mesenchymal stem cells (MSCs) has been shown to be related to various human metabolic diseases, such as obesity and osteoporosis; however, the underlying mechanisms remain elusive. We found that the interaction between osteopontin (OPN), an arginine-glycine-aspartate-containing glycoprotein, and integrin αv/β1 plays a critical role in the lineage determination of MSCs. Although OPN is a well-established marker during osteogenesis, its role in MSC differentiation is still unknown. Our study reveals that blockade of OPN function promoted robust adipogenic differentiation, while inhibiting osteogenic differentiation. Re-expression of OPN restored a normal balance between adipogenesis and osteogenesis in OPN−/− MSCs. Retarded bone formation by OPN−/− MSCs was also verified by in vivo implantation with hydroxyapatite-tricalcium phosphate, a bone-forming matrix. The role of extracellular OPN in MSC differentiation was further demonstrated by supplementation and neutralization of OPN. Blocking well-known OPN receptors integrin αv/β1 but not CD44 also affected MSC differentiation. Further studies revealed that OPN inhibits the C/EBPs signaling pathway through integrin αv/β1. Consistent with these in vitro results, OPN−/− mice had a higher fat to total body weight ratio than did wild-type mice. Therefore, our study demonstrates a novel role for OPN-integrin αv/β1 in regulating MSC differentiation. S tem C ells 2014;32:327-337 [ABSTRACT FROM AUTHOR]

Disruption of adenylyl cyclase type 5 ( AC5) knockout ( KO) is a novel model for longevity. Because malignancy is a major cause of death and reduced lifespan in mice, the goal of this investigation was to examine the role of AC5 KO in protecting against cancer. There have been numerous discoveries in genetically engineered mice over the past several decades, but few have been translated to the bedside. One major reason is that it is difficult to alter a gene in patients, but rather a pharmacological approach is more appropriate. The current investigation employs a parallel construction to examine the extent to which inhibiting AC5, either in a genetic knockout ( KO) or by a specific pharmacological inhibitor protects against cancer. This study is unique, not only because a combined genetic and pharmacological approach is rare, but also there are no prior studies on the extent to which AC5 affects cancer. We found that AC5 KO delayed age-related tumor incidence significantly, as well as protecting against mammary tumor development in AC5 KO × MMTV- HER-2 neu mice, and B16F10 melanoma tumor growth, which can explain why AC5 KO is a model of longevity. In addition, a Food and Drug Administration approved antiviral agent, adenine 9-β-D-arabinofuranoside (Vidarabine or AraAde), which specifically inhibits AC5, reduces LP07 lung and B16F10 melanoma tumor growth in syngeneic mice. Thus, inhibition of AC5 is a previously unreported mechanism for prevention of cancers associated with aging and that can be targeted by an available pharmacologic inhibitor, with potential consequent extension of lifespan. [ABSTRACT FROM AUTHOR]

The mechanisms by which inflammation or autoimmunity causes proteinuric kidney disease remain elusive. Yet proteinuria is a hallmark and a prognostic indicator of kidney disease, and also an independent risk factor for cardiovascular morbidity and mortality. Podocytes are an integral component of the kidney filtration barrier and podocyte injury leads to proteinuria. Here we show that podocytes, which receive signals from the vascular space including circulating antigens, constitutively express TLR1-6 and TLR8. We find that podocytes can respond to TLR ligands including staphylococcal enterotoxin B ( SEB), poly I:C, or lipopolysaccharide ( LPS) with pro-inflammatory cytokine release and activation of type I interferon ( IFN) signalling. This in turn stimulates podocyte B7-1 expression and actin remodelling in vitro and transient proteinuria in vivo. Importantly, the treatment of mice with a type I IFN receptor-blocking antibody (Ab) prevents LPS-induced proteinuria. These results significantly extend our understanding of podocyte response to immune stimuli and reveal a novel mechanism for infection- or inflammation-induced transient proteinuria. Dysregulation or aberrant activation of this response may result in persistent proteinuria and progressive glomerular disease. In summary, the inhibition of glomerular type I IFN signalling with anti- IFN Abs may be a novel therapy for proteinuric kidney diseases. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We investigated the effects of caloric restriction (CR) on growth of tumors and metastases in the 4T1 mammary tumor model and found that CR, compared with normal diet, reduced the growth of mammary tumors and metastases and the total number of metastases that originated both spontaneously from the primary tumor and also experimentally from i.v. injection of the tumor cells. CR also decreased proliferation and angiogenesis and increased apoptosis in tumors. CR reduced levels of insulin, leptin, insulin-like growth factor 1, insulin-like growth factor binding protein 3 and increased adiponectin in tumors. We also demonstrated that tumors from CR mice possessed lower levels of transforming growth factor-β, lower intratumor deposition of collagen IV and reduced invasiveness due to a decrease in tumor secretion of active matrix metalloproteinase 9. Our results suggest that CR-induced metabolic and signaling changes affect the stroma and the tumor cells resulting in a microenvironment that prevents proliferation of breast tumors and their metastases. [ABSTRACT FROM AUTHOR]

Aims Tumours secrete proangiogenic factors to induce the ingrowth of blood vessels, the end targets of which are vascular endothelial cells (ECs). The MEOX2 homeoprotein inhibits nuclear factor-κB (NF-κB) signalling and EC activation in response to serum and proangiogenic factors. We hypothesize that MEOX2 interacts with components of this pathway in vascular ECs to modulate NF-κB activity and EC activation and that these interactions depend upon specific domains within the MEOX2 protein. Methods and results To test our hypothesis, we transduced ECs with MEOX2 expression constructs. MEOX2 protein localized to the nuclear fraction, as did IκBβ and p65. By co-immunoprecipitation, MEOX2 bound to both p65 and IκBβ. Immuno-fluorescence demonstrated that MEOX2 colocalizes in the nucleus with both p65 and IκBβ and that this colocalization requires the MEOX2 homeodomain and N-terminal domain. Finally, promoter assays revealed that MEOX2 expression has a biphasic effect on NF-κB-dependent promoters. At low levels, MEOX2 stimulates NF-κB activity, whereas at high levels, it represses, effects that also depend upon the homeodomain and the N-terminal domain. Conclusion Our results represent the first report of an interaction between a homeobox protein and IκBβ and suggest that MEOX2 modulates the activity of the RelA complex through direct interaction with its components. These observations implicate MEOX2 as a potentially important regulatory gene inhibiting not only the angiogenic response of ECs to proangiogenic factors, but also their response to chronic inflammatory stimulation that normally activates NF-κB, suggesting MEOX2 as a possible molecular target for the therapy of angiogenesis-dependent diseases such as cancer. [ABSTRACT FROM AUTHOR]

Bone marrow-derived mesenchymal stem cells (MSCs) hold great promise for treating immune disorders because of their immunoregulatory capacity, but the mechanism remains controversial. As we show here, the mechanism of MSC-mediated immunosuppression varies among different species. Immunosuppression by human- or monkey-derived MSCs is mediated by indoleamine 2,3-dioxygenase (IDO), whereas mouse MSCs utilize nitric oxide, under the same culture conditions. When the expression of IDO and inducible nitric oxide synthase (iNOS) were examined in human and mouse MSCs after stimulation with their respective inflammatory cytokines, we found that human MSCs expressed extremely high levels of IDO, and very low levels of iNOS, whereas mouse MSCs expressed abundant iNOS and very little IDO. Immunosuppression by human MSCs was not intrinsic, but was induced by inflammatory cytokines and was chemokine-dependent, as it is in mouse. These findings provide critical information about the immunosuppression of MSCs and for better application of MSCs in treating immune disorders. [ABSTRACT FROM AUTHOR]

Describes the adenovirus infection of primary malignant lymphoid cells. Induction of host cell pro-apoptotic responses; Mechanism of cell cycle regulation; Activation of regulatory pathways in malignant cells.

C-terminal truncations of the NFKB2 p100 gene product have been observed in a number of cases of human cutaneous T cell lymphomas, as well as human B-cell lymphomas and myelomas. The contribution of these alterations to lymphomagenesis is not understood; however, truncation at amino acid 666 to generate 80–85 kD proteins in the HUT78 cell line is associated with addition of a short (serine-alanine-serine) fusion at the 3′ end of p80HT, as well as with increased expression of NFKB2 mRNA. We therefore examined the effects of p80HT on the regulation of NFKB2 expression, as well as the properties of a series of other tumor-associated, and site directed mutations of NFKB2. While p80HT had not itself acquired novel transcriptional activation properties with respect to the NFKB2 P1 or P2 promoters or the IL-6 κB promoter, p80HT had lost the potent inhibitory (IκB-like) activity associated with the wild-type, p100 gene product. Loss of the inhibitory property depended on the SAS residues in the fusion protein, direct truncation at aa666 was fully inhibitory, as was a substitution of three alanines for the SAS residues. The presence of as few as two C-terminal ankyrin motifs was sufficient for inhibition of NF-κB-mediated transcriptional activation. Assays of a series of additional lymphoma-associated NF-κB-2 truncation suggested that the C-terminal truncation associated with these proteins was also associated with a loss of the IκB-like activities of p100 NF-κB-2, for at least some NF-κB target promoters. Thus, the loss of IκB-like activity of lymphoma-associated NFKB2 mutations may play an important role in the genesis of a subset of human lymphomas. Oncogene (2000) 19, 1334–1345. [ABSTRACT FROM AUTHOR]

To understand the potential role of placental tissue in the pathogenesis of neonatal AIDS, the distribution of human immunodeficiency virus type 1 (HIV-l) receptor and the infectability of placental tissue by HIV-l were studied. Both the mRNA and the protein for the HIV receptor (CD4) were present in fetal-derived placenta. By immunofluorescent microscopy, a number of different cell types appeared to be CD4+; positive cells were observed in the lining and stroma of the chorionic villi. Some of these CD4+ cells dual-labeled with the trophoblastic marker placental lactogen. In addition, CD4+ cells were observed within the lining of placental blood vessels. Organ cultures of first-trimester and term placentas were infectable by HIV as monitored by reverse transcriptase activity of culture supernatants and by immunofluorescent labeling of HIV antigens. One potential route of congenital HIV transmission may be direct placental infection by HIV as early as the first trimester, with subsequent transplacental spread of the virus. [ABSTRACT FROM PUBLISHER]

Infection with human T-cell leukemia/lymphoma virus type 1 (HTLV-1) has been associated with various clinical syndromes including co-infection with Strongyloides stercoralis, which is an intestinal parasitic nematode and the leading cause of strongyloidiasis in humans. Interestingly, HTLV-1 endemic areas coincide with regions citing high prevalence of S. stercoralis infection, making these communities optimal for elucidating the pathogenesis of co-infection and its clinical significance. HTLV-1 co-infection with S. stercoralis has been observed for decades in a number of published patient cases and case series; however, the implications of this co-infection remain elusive. Thus far, data suggest that S. stercoralis increases proviral load in patients co-infected with HTLV-1 compared to HTLV-1 infection alone. Furthermore, co-infection with HTLV-1 has been associated with shifting the immune response from Th2 to Th1, affecting the ability of the immune system to address the helminth infection. Thus, despite this well-known association, further research is required to fully elucidate the impact of each pathogen on disease manifestations in co-infected patients. This review provides an analytical view of studies that have evaluated the variation within HTLV-1 patients in susceptibility to S. stercoralis infection, as well as the effects of strongyloidiasis on HTLV-1 pathogenesis. Further, it provides a compilation of available clinical reports on the epidemiology and pathology of HTLV-1 with parasitic co-infection as well as data from mechanistic studies suggesting possible immunopathogenic mechanisms. Furthermore, specific areas of potential future research have been highlighted to facilitate advancing understanding of the complex interactions between these two pathogens. [ABSTRACT FROM AUTHOR]

An abstract of the research paper titled,"Coordination of the canonical and noncanonical IKK/NF-kB signaling pathways in the Human T-cell leukemia virus type 1 (HTLV-1) Taxmediated tumorigenesis," is presented.

An abstract of the research paper titled " Activation of HTLV-1 Expression in Chronically-Infected CD4+ T cells: Mechanisms and Implications for Pathogenesis," by Alison Swaims, Hsin-Ching Lin, Peter Simon, Celine Granier, Yingyu Zhang, Arthur Roberts and Satish Devadas is presented.

Tumors secrete proangiogenic factors to induce the ingrowth of blood vessels from the stroma. These peptides bind to cell surface receptors on vascular endothelial cells (ECs), triggering signaling cascades that activate and repress batteries of downstream genes responsible for the angiogenic phenotype. To determine if microRNAs (miRNAs) affect regulation of the EC phenotype by GAX, a homeobox gene and negative transcriptional regulator of the angiogenic phenotype, we tested the effect of miR-221 on GAX expression. miR-221 strongly upregulated GAX, suggesting that miR-221 downregulates a repressor of GAX. We next expressed miR-221 in ECs and identified ZEB2, a modulator of the epithelial-mesenchymal transition, as being strongly downregulated by miR-221. Using miR-221 expression constructs and an inhibitor, we determined that ZEB2 is upregulated by serum and downregulates GAX, while the expression of miR-221 upregulates GAX and downregulates ZEB2. A mutant miR-221 fails to downregulate ZEB2 or upregulate GAX. Finally, using chromatin immunoprecipitation, we identified two ZEB2 binding sites that modulate the ability of ZEB2 to downregulate GAX promoter activity. We conclude that miR-221 upregulates GAX primarily through its ability to downregulate the expression of ZEB2. These observations suggest a strategy for inhibiting angiogenesis by either recapitulating miR-221 expression or inhibiting ZEB2 activation. [ABSTRACT FROM AUTHOR]