123 research outputs found
Frequency and Significance of HIV Infection among Patients Diagnosed with Thrombotic Thrombocytopenic Purpura
Background. Case series of patients with a diagnosis of thrombotic thrombocytopenic purpura (TTP) have reported different frequencies of human immunodeficiency virus (HIV) infection; some series suggest that HIV infection may cause TTP. Methods. We systematically reviewed all reports of HIV infection in case series of patients with TTP. We analyzed data from the Oklahoma TTP-HUS (hemolytic uremic syndrome) Registry, an inception cohort of 362 consecutive patients, for 1989-2007. Results. Nineteen case series reported the occurrence of HIV infection at the time of diagnosis of TTP in 0%-83% of patients; individual patient data were rarely described. The Oklahoma TTP-HUS Registry determined the HIV status at the time of diagnosis of TTP in 351 (97%) of 362 patients. HIV infection was documented in 6 (1.84%; 95% CI, 0.68%-4.01%) of 326 adult patients (age, 26-51 years); follow-up data were complete for all 6 patients. The period prevalence of HIV infection among all adults in the Oklahoma TTP-HUS Registry region for 1989-2007 was 0.30%. One patient had typical features of TTP with 5 relapses. Five patients had single episodes; in 4, the clinical features that had initially suggested the diagnosis of TTP were subsequently attributed to malignant hypertension (in 3 patients) and disseminated Kaposi sarcoma (in 1 patient). Conclusions. HIV infection, similar to other inflammatory conditions, may trigger acute episodes of TTP in susceptible patients. More commonly, acquired immunodeficiency syndrome-related disorders may mimic the clinical features of TTP. If the diagnosis of TTP is suggested in a patient with HIV infection, there should be careful evaluation for alternative diagnoses and cautious consideration of plasma exchange, the required treatment for TT
Nuclear factor kappa B pathway associated biomarkers in AIDS defining malignancies
The Nuclear Factor kappa B (NFkB) pathway is essential for many human cancers. Therapeutics such as bortezomib (Velcadeâ„¢), which interfere with nuclear factor NF-kappa-B(NFkB)signaling are of great clinical interest. NFkB signaling, however, is multifaceted and variable among tissues, developmental, and disease entities. Hence, targeted biomarkers of NFkB pathways are of prime importance for clinical research. We developed a novel real-time qPCR-based NFkB array. Only mechanistically validated NFkB targets were included. We then used random-forest classification to define individual genes and gene combinations within the NFkB pathways that define viral lymphoma subclasses as well as Kaposi sarcoma (KS). Few NFkB targets emerged that were universally present in all tumor types tested, underscoring the need for additional tumor-type specific biomarker discovery. (i) We uncovered tissue of origin-specific tumor markers, specifically CD69, CSF-1, and complement factor B (C1QBP)for PEL; IL1-beta, cyclinD3 and CD48for KS. We found that IL12, jun-B, msx-1 and thrombospondin 2 were associated with EBV co-infection in PEL. (ii) We defined the NFkB signature of Epstein-Barr virus (EBV)positive AIDS-associated Burkitt lymphoma(BL). This signature identified CCR5 as the key marker. (iii) This signature differed from EBV negative BL consistent with the idea that EBV not only activates NFkB activity but that this virus also reprograms NFkB signaling towards different targets
Home use of a bihormonal bionic pancreas versus insulin pump therapy in adults with type 1 diabetes: a multicentre randomised crossover trial
The safety and effectiveness of a continuous, day-and-night automated glycaemic control system using insulin and glucagon has not been shown in a free-living, home-use setting. We aimed to assess whether bihormonal bionic pancreas initialised only with body mass can safely reduce mean glycaemia and hypoglycaemia in adults with type 1 diabetes who were living at home and participating in their normal daily routines without restrictions on diet or physical activity
Immunogenomic profiling determines responses to combined PARP and PD-1 inhibition in ovarian cancer
Combined PARP and immune checkpoint inhibition has yielded encouraging results in ovarian cancer, but predictive biomarkers are lacking. We performed immunogenomic profiling and highly multiplexed single-cell imaging on tumor samples from patients enrolled in a Phase I/II trial of niraparib and pembrolizumab in ovarian cancer (NCT02657889). We identify two determinants of response; mutational signature 3 reflecting defective homologous recombination DNA repair, and positive immune score as a surrogate of interferon-primed exhausted CD8+T-cells in the tumor microenvironment. Presence of one or both features associates with an improved outcome while concurrent absence yields no responses. Single-cell spatial analysis reveals prominent interactions of exhausted CD8+T-cells and PD-L1+macrophages and PD-L1+tumor cells as mechanistic determinants of response. Furthermore, spatial analysis of two extreme responders shows differential clustering of exhausted CD8+T-cells with PD-L1+macrophages in the first, and exhausted CD8+T-cells with cancer cells harboring genomic PD-L1 and PD-L2 amplification in the second. A Phase I/II trial previously revealed variable anti-tumor efficacy of the PARP inhibitor niraparib in combination with the PD-1 inhibitor pembrolizumab in platinum-resistant ovarian cancer patients. Here, the authors perform an integrated genomic and immunomics analysis of tumor samples from the same patients and find potential predictive biomarkers of response to such combination therapy.Peer reviewe
HIV-associated bladder cancer: a case series evaluating difficulties in diagnosis and management
<p>Abstract</p> <p>Background</p> <p>Chronic human immunodeficiency virus (HIV) infection is associated with an increased incidence of Non-Acquired Immunodeficiency Syndrome (non-AIDS) defining cancers. To date, only a limited number of cases of bladder cancer have been linked with HIV infection. We sought to describe the clinical characteristics of HIV-associated bladder cancer.</p> <p>Methods</p> <p>A retrospective study was performed involving HIV-positive patients with bladder cancer, combining cases from multiple institutions with published case reports. Data regarding patient demographics, HIV status, clinical presentation, pathology, cancer treatment, and outcome were analyzed using descriptive statistics.</p> <p>Results</p> <p>Eleven patients were identified with a median age of 55 years (range, 33 - 67). The median CD4+ count at cancer diagnosis was 280 cells/mm<sup>3 </sup>(range, 106 - 572 cells/mm<sup>3</sup>). Six patients (55%) had a known risk factor for bladder cancer, and nine (82%) presented with hematuria. Ten patients had transitional cell carcinoma, and most had superficial disease at presentation. Treatment included mainly transurethral resection of bladder tumor followed by a combination of local and systemic therapies. One patient received intravesical bacillus Calmette-Guèrin (BCG) without complication. Several patients (55%) were alive following therapy, although many (64%) suffered from local relapse and metastatic disease.</p> <p>Conclusion</p> <p>Bladder cancer is part of the growing list of cancers that may be encountered in patients living longer with chronic HIV-infection. Our patients presented at a younger age and with only mild immunosuppression, however, they experienced an expected course for their bladder cancer. Hematuria in an HIV-infected patient warrants a complete evaluation.</p
Leishmania infantum Amastigotes Enhance HIV-1 Production in Cocultures of Human Dendritic Cells and CD4+ T Cells by Inducing Secretion of IL-6 and TNF-α
Visceral leishmaniasis (VL) is a potentially deadly parasitic disease afflicting millions worldwide. Although itself an important infectious illness, VL has also emerged as an opportunistic disease among patients infected with HIV-1. This is partly due to the increasing overlap between urban regions of high HIV-1 transmission and areas where Leishmania is endemic. Furthermore, VL increases the development and clinical progression of AIDS-related diseases. Conversely, HIV-1-infected individuals are at greater risk of developing VL or suffering relapse. Finally, HIV-1 and Leishmania can both productively infect cells of the macrophage-dendritic cell lineage, resulting in a cumulative deficiency of the immune response. We therefore studied the effect of Leishmania infantum on HIV-1 production when dendritic cells (DCs) are cocultured with autologous CD4+ T cells. We show that amastigotes promote virus replication in both DCs and lymphocytes, due to a parasite-mediated production of soluble factors by DCs. Micro-beads array analyses indicate that Leishmania infantum amastigotes infection induces a higher secretion of several cytokines in these cells, and use of specific neutralizing antibodies revealed that the Leishmania-induced increase in HIV-1 replication is due to IL-6 and TNF-α. These findings suggest that Leishmania's presence within DC/T-cell conjugates leads to an enhanced HIV-1 production
HIV-1 Tat mimetic of VEGF correlates with increased microvessels density in AIDS-related diffuse large B-cell and Burkitt lymphomas
Angiogenic switch marks the beginning of tumor’s strategy to acquire independent blood supply. In some subtypes of non-Hodgkin’s lymphomas, higher local vascular endothelial growth factor (VEGF) expression correlates with increased microvessel density. However, this local VEGF expression is higher only in tumors with elevated expression of the receptors of the growth factor, suggesting an autocrine growth-promoting feedback loop. Several studies have indicated that VEGF receptors are also targeted by Tat protein from the HIV-1-infected cells. Given the similarity of the basic region of Tat to the angiogenic factors (basic fibroblast growth factor, VEGF), Tat mimics these proteins and binds to their receptors. We evaluated the role of HIV-1 Tat in regulating the level of VEGF expression and microvessel density in the AIDS-related diffuse large B-cell (DLBCL) and Burkitt lymphomas (BL). By luciferase assay, we showed that VEGF promoter activity was downregulated in vitro in cells transfected with Tat. Reduced VEGF protein expression in primary HIV-1 positive BL and DLBCL, compared to the negative cases, supported the findings of promoter downregulation from the cell lines. Microvascular density assessed by CD34 expression was, however, higher in HIV-1 positive than in HIV-1 negative tumors. These results suggest that Tat has a wider angiogenic role, besides the regulation of VEGF expression. Thus, targeting Tat protein itself and stabilizing transient silencing of VEGF expression or use of monoclonal antibodies against their receptors in the AIDS-associated tumors will open a window for future explorable pathways in the management of angiogenic phenotypes in the AIDS-associated non-Hodgkin’s lymphomas
Update on HHV-8-Associated Malignancies
The human herpesvirus 8 (HHV-8) is the oncogenic virus associated with Kaposi’s sarcoma (KS) and lymphoproliferative disorders, namely, primary effusion lymphoma and multicentric Castleman’s disease. KS is among the most common malignancies seen in HIV-infected patients despite the decreased incidence of KS in the era of highly active antiretroviral therapy. Advances in molecular pathology reveal HHV-8 tumorigenesis is mediated through molecular mimicry wherein viral-encoded proteins can activate several cellular signaling cascades while evading immune surveillance. This knowledge has led to the evolution of multiple therapeutic strategies against specific molecular targets. Many such therapeutic modalities have shown activity, but none have proven to be curative. Identifying possible prognostic factors is another active area of research. This review summarizes the recent developments in the fields of virus transmission, molecular biology, and treatment of HHV-8-related neoplasms
Ibudilast, a Pharmacologic Phosphodiesterase Inhibitor, Prevents Human Immunodeficiency Virus-1 Tat-Mediated Activation of Microglial Cells
Human Immunodeficiency Virus-1 (HIV-1)-associated neurocognitive disorders (HAND) occur, in part, due to the inflammatory response to viral proteins, such as the HIV-1 transactivator of transcription (Tat), in the central nervous system (CNS). Given the need for novel adjunctive therapies for HAND, we hypothesized that ibudilast would inhibit Tat-induced excess production of pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNFα) in microglial cells. Ibudilast is a non-selective cyclic AMP phosphodiesterase inhibitor that has recently shown promise as a treatment for neuropathic pain via its ability to attenuate glial cell activation. Accordingly, here we demonstrate that pre-treatment of both human and mouse microglial cells with increasing doses of ibudilast inhibited Tat-induced synthesis of TNFα by microglial cells in a manner dependent on serine/threonine protein phosphatase activity. Ibudilast had no effect on Tat-induced p38 MAP kinase activation, and blockade of adenosine A2A receptor activation did not reverse ibudilast's inhibition of Tat-induced TNFα production. Interestingly, ibudilast reduced Tat-mediated transcription of TNFα, via modulation of nuclear factor-kappa B (NF-κB) signaling, as shown by transcriptional activity of NF-κB and analysis of inhibitor of kappa B alpha (IκBα) stability. Together, our findings shed light on the mechanism of ibudilast's inhibition of Tat-induced TNFα production in microglial cells and may implicate ibudilast as a potential novel adjunctive therapy for the management of HAND
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