Impairment of T cell development and acute inflammatory response in HIV-1 Tat transgenic mice

Immune activation and chronic inflammation are hallmark features of HIV infection causing T-cell depletion and cellular immune dysfunction in AIDS. Here, we addressed the issue whether HIV-1 Tat could affect T cell development and acute inflammatory response by generating a transgenic mouse expressing Tat in lymphoid tissue. Tat-Tg mice showed thymus atrophy and the maturation block from DN4 to DP thymic subpopulations, resulting in CD4(+) and CD8(+) T cells depletion in peripheral blood. In Tat-positive thymus, we observed the increased p65/NF-κB activity and deregulated expression of cytokines/chemokines and microRNA-181a-1, which are involved in T-lymphopoiesis. Upon LPS intraperitoneal injection, Tat-Tg mice developed an abnormal acute inflammatory response, which was characterized by enhanced lethality and production of inflammatory cytokines. Based on these findings, Tat-Tg mouse could represent an animal model for testing adjunctive therapies of HIV-1-associated inflammation and immune deregulation

IBTK contributes to B-cell lymphomagenesis in Eμ-myc transgenic mice conferring resistance to apoptosis

Abstract Increasing evidence supports the involvement of IBTK in cell survival and tumor growth. Previously, we have shown that IBTK RNA interference affects the wide genome expression and RNA splicing in cell-type specific manner. Further, the expression of IBTK gene progressively increases from indolent to aggressive stage of chronic lymphocytic leukemia and decreases in disease remission after therapy. However, the role of IBTK in tumorigenesis has not been elucidated. Here, we report that loss of the murine Ibtk gene raises survival and delays tumor onset in Eμ-myc transgenic mice, a preclinical model of Myc-driven lymphoma. In particular, we found that the number of pre-cancerous B cells of bone marrow and spleen is reduced in Ibtk −/− Eμ-myc mice owing to impaired viability and increased apoptosis, as measured by Annexin V binding, Caspase 3/7 cleavage assays and cell cycle profile analysis. Instead, the proliferation rate of pre-cancerous B cells is unaffected by the loss of Ibtk. We observed a direct correlation between Ibtk and myc expression and demonstrated a Myc-dependent regulation of Ibtk expression in murine B cells, human hematopoietic and nonhematopoietic cell lines by analysis of ChIP-seq data. By tet-repressible Myc system, we confirmed a Myc-dependent expression of IBTK in human B cells. Further, we showed that Ibtk loss affected the main apoptotic pathways dependent on Myc overexpression in pre-cancerous Eμ-myc mice, in particular, MCL-1 and p53. Of note, we found that loss of IBTK impaired cell cycle and increased apoptosis also in a human epithelial cell line, HeLa cells, in Myc-independent manner. Taken together, these results suggest that Ibtk sustains the oncogenic activity of Myc by inhibiting apoptosis of murine pre-cancerous B cells, as a cell-specific mechanism. Our findings could be relevant for the development of IBTK inhibitors sensitizing tumor cells to apoptosis

The effects of sulodexide on both clinical and molecular parameters in patients with mixed arterial and venous ulcers of lower limbs

BACKGROUND: Mixed venous and arterial ulcers account for approximately 15%–30% of all venous leg ulcerations. Several studies have shown that matrix metalloproteinases (MMPs) and neutrophil gelatinase-associated lipocalin (NGAL) play a central role in the pathophysiology of venous and arterial diseases. Some studies have shown the efficacy of glycosaminoglycans, such as sulodexide (SDX), in treating patients with leg ulcers. The aim of this study was to evaluate clinical effects of SDX and its correlation with MMPs and NGAL expression in patients with mixed arterial and venous leg ulcers. METHODS: Patients eligible for this study were of both sexes, older than 20 years, and with a clinical and instrumental diagnosis of mixed ulcer. RESULTS: Fifty-three patients of both sexes were enrolled and divided into two groups by means of randomization tables. Group A (treated group) comprised 18 females and ten males (median age: 68.7 years) treated with standard treatment (compression therapy and surgery) + SDX (600 lipoprotein lipase-releasing units/day intramuscularly) for 15 days followed by SDX 250 lipase-releasing units every 12 hours day orally for 6 months as adjunctive treatment. Group B (control group) comprised 17 females and eight males (median age: 64.2 years) treated with standard treatment only (compression therapy and surgery). The type of surgery was chosen according to anatomical level of vein incompetence: superficial venous open surgery and/or subfascial endoscopic perforating surgery. In all enrolled patients, blood samples were collected in order to evaluate the plasma levels of MMPs and NGAL through enzyme-linked immunosorbent assay. These results were compared to another control group (Group C) of healthy individuals. Moreover, biopsies of ulcers were taken to evaluate the tissue expression of MMPs and NGAL through Western blot analysis. Our results revealed that SDX treatment is able to reduce both plasma levels and tissue expression of MMPs improving the clinical conditions in patients with mixed ulcers. CONCLUSION: Inhibition of MMPs could represent a possible therapeutic intervention to limit the progression of leg ulceration. In particular, our findings demonstrate the efficacy of SDX in patients with mixed arterial and venous chronic ulcers of the lower limbs

IBTK Differently Modulates Gene Expression and RNA Splicing in HeLa and K562 Cells

The IBTK gene encodes the major protein isoform IBTKα that was recently characterized as substrate receptor of Cul3-dependent E3 ligase, regulating ubiquitination coupled to proteasomal degradation of Pdcd4, an inhibitor of translation. Due to the presence of Ankyrin-BTB-RCC1 domains that mediate several protein-protein interactions, IBTKα could exert expanded regulatory roles, including interaction with transcription regulators. To verify the effects of IBTKα on gene expression, we analyzed HeLa and K562 cell transcriptomes by RNA-Sequencing before and after IBTK knock-down by shRNA transduction. In HeLa cells, 1285 (2.03%) of 63,128 mapped transcripts were differentially expressed in IBTK-shRNA-transduced cells, as compared to cells treated with control-shRNA, with 587 upregulated (45.7%) and 698 downregulated (54.3%) RNAs. In K562 cells, 1959 (3.1%) of 63128 mapped RNAs were differentially expressed in IBTK-shRNA-transduced cells, including 1053 upregulated (53.7%) and 906 downregulated (46.3%). Only 137 transcripts (0.22%) were commonly deregulated by IBTK silencing in both HeLa and K562 cells, indicating that most IBTKα effects on gene expression are cell type-specific. Based on gene ontology classification, the genes responsive to IBTK are involved in different biological processes, including in particular chromatin and nucleosomal organization, gene expression regulation, and cellular traffic and migration. In addition, IBTK RNA interference affected RNA maturation in both cell lines, as shown by the evidence of alternative 3′- and 5′-splicing, mutually exclusive exons, retained introns, and skipped exons. Altogether, these results indicate that IBTK differently modulates gene expression and RNA splicing in HeLa and K562 cells, demonstrating a novel biological role of this protein

Additional file 1: Table S1. of Monitoring multiple myeloma by idiotype-specific peptide binders of tumor-derived exosomes

Percentage of p5-FITC positive TDEs population after tumor cells injection. Figure S1. Flow cytometry analysis of purified exosomes derived from different cell sources (DOC 570 kb