140 research outputs found

    Three-dimensional image surface acquisition in vertebrate paleontology: A review of principal techniques

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    Three-dimensional (3D) surface scanning includes techniques of image acquisition and image processing. Among the former, hardware devices (e.g., portable and non-portable scanners, camera) capture images from the target, whereas image processing is conducted via specialized software, in which acquired images are processed to merge them into a single 3D surface model. Image surface scanning comprises a wide variety of devices which incorporate different image acquisition techniques, all of them with potential high standards results. We describe four different scanning devices and techniques commonly used in vertebrate paleontology in order to compare them in terms of pros and cons, considering different variables, such as scanning time, post-processing time, costs and image resolution. The decision on which device to choose will depend on the budget available, the portability as well as the nature of the fossil material being analyzed (e.g., size, weight, accessibility). In the light of this, photogrammetry constitutes the image surface technique which fulfills these requirements, having the best cost-benefit relationship

    Antigen glycosylation regulates efficacy of CAR T cells targeting CD19

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    While chimeric antigen receptor (CAR) T cells targeting CD19 can cure a subset of patients with B cell malignancies, most patients treated will not achieve durable remission. Identification of the mechanisms leading to failure is essential to broadening the efficacy of this promising platform. Several studies have demonstrated that disruption of CD19 genes and transcripts can lead to disease relapse after initial response; however, few other tumor-intrinsic drivers of CAR T cell failure have been reported. Here we identify expression of the Golgi-resident intramembrane protease Signal peptide peptidase-like 3 (SPPL3) in malignant B cells as a potent regulator of resistance to CAR therapy. Loss of SPPL3 results in hyperglycosylation of CD19, an alteration that directly inhibits CAR T cell effector function and suppresses anti-tumor cytotoxicity. Alternatively, over-expression of SPPL3 drives loss of CD19 protein, also enabling resistance. In this pre-clinical model these findings identify post-translational modification of CD19 as a mechanism of antigen escape from CAR T cell therapy

    Acute Kidney Injury Following Chimeric Antigen Receptor T-Cell Therapy for B-Cell Lymphoma in a Kidney Transplant Recipient

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    Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy is a newer and effective therapeutic option approved for patients with relapsed/refractory acute lymphoblastic leukemia and diffuse large B-cell lymphoma. Acute kidney injury is a complication of CAR T-cell therapy that can result in kidney failure. In most cases, it is thought to be related to hemodynamic changes due to cytokine release syndrome. Kidney biopsy in this clinical scenario is usually not performed. We report on a kidney transplant recipient in his 40s who developed a posttransplant lymphoproliferative disorder of B-cell origin refractory to conventional treatments and received anti-CD19 CAR T-cell therapy as compassionate treatment. Beginning on day 12 after CAR T-cell infusion, in the absence of clinical symptoms, a progressive decline in estimated glomerular filtration rate of the kidney graft occurred. A subsequent allograft biopsy showed mild tubulointerstitial lymphocyte infiltrates, falling into a Banff borderline-changes category and resembling an acute immunoallergic tubulointerstitial nephritis. Neither CAR T cells nor lymphomatous B cells were detected within the graft cellular infiltrates, suggesting an indirect mechanism of kidney injury. Although kidney graft function partially recovered after steroid therapy, the posttransplant lymphoproliferative disorder progressed and the patient died 7 months later

    Immunogenicity of CAR T cells in cancer therapy

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    Patient-derived T cells genetically reprogrammed to express CD19-specific chimeric antigen receptors (CARs) have shown remarkable clinical responses and are commercially available for the treatment of patients with certain advanced-stage B cell malignancies. Nonetheless, several trials have revealed pre-existing and/or treatment-induced immune responses to the mouse-derived single-chain variable fragments included in these constructs. These responses might have contributed to both treatment failure and the limited success of redosing strategies observed in some patients. Data from early phase clinical trials suggest that CAR T cells are also associated with immunogenicity-related events in patients with solid tumours. Generally, the clinical implications of anti-CAR immune responses are poorly understood and highly variable between different CAR constructs and malignancies. These observations highlight an urgent need to uncover the mechanisms of immunogenicity in patients receiving CAR T cells and develop validated assays to enable clinical detection. In this Review, we describe the current clinical evidence of anti-CAR immune responses and discuss how new CAR T cell technologies might impact the risk of immunogenicity. We then suggest ways to reduce the risks of anti-CAR immune responses to CAR T cell products that are advancing towards the clinic. Finally, we summarize measures that investigators could consider in order to systematically monitor and better comprehend the possible effects of immunogenicity during trials involving CAR T cells as well as in routine clinical practice

    Rate of primary refractory disease in B and T-cell non-Hodgkin's lymphoma: correlation with long-term survival

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    BACKGROUND: Primary refractory disease is a main challenge in the management of non-Hodgkin's Lymphoma (NHL). This survey was performed to define the rate of refractory disease to first-line therapy in B and T-cell NHL subtypes and the long-term survival of primary refractory compared to primary responsive patients. METHODS: Medical records were reviewed of 3,106 patients who had undergone primary treatment for NHL between 1982 and 2012, at the Hematology Centers of Torino and Bergamo, Italy. Primary treatment included CHOP or CHOP-like regimens (63.2%), intensive therapy with autograft (16.9%), or other therapies (19.9%). Among B-cell NHL, 1,356 (47.8%) received first-line chemotherapy with rituximab. Refractory disease was defined as stable/progressive disease, or transient response with disease progression within six months. RESULTS: Overall, 690 (22.2%) patients showed primary refractory disease, with a higher incidence amongst T-cell compared to B-cell NHL (41.9% vs. 20.5%, respectively, p<0.001). Several other clinico-pathological factors at presentation were variably associated with refractory disease, including histological aggressive disease, unfavorable clinical presentation, Bone Marrow involvement, low lymphocyte/monocyte ration and male gender. Amongst B-cell NHL, the addition of rituximab was associated with a marked reduction of refractory disease (13.6% vs. 26.7% for non-supplemented chemotherapy, p<0.001). Overall, primary responsive patients had a median survival of 19.8 years, compared to 1.3 yr. for refractory patients. A prolonged survival was consistently observed in all primary responsive patients regardless of the histology. The long life expectancy of primary responsive patients was documented in both series managed before and after 2.000. Response to first line therapy resulted by far the most predictive factor for long-term outcome (HR for primary refractory disease: 16.52, p<0.001). CONCLUSION: Chemosensitivity to primary treatment is crucial for the long-term survival in NHL. This supports the necessity of studies aimed to early identify refractory disease and to develop different treatment strategies for responsive and refractory patients

    Microvertebrates preserved in mammal burrows from the Holocene of the Argentine Pampas: a taphonomic and paleoecological approach

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    Microvertebrates are a major component of many assemblages recovered from the Quaternary of the Argentine Pampas. The main goal of this paper is to analyse the taphonomic history of a Holocene microfossil bonebed, recovered from the infilling of a burrow. Evidences suggest the plains vizcacha Lagostomus maximus as the putative producer of the burrow. The assemblage includes individuals belonging to different taxa of mammals (marsupials and rodents) and reptiles (snakes). Taphonomic features suggest that the accumulation inside the burrow was related to flooding processes in the plain. The burrow was a natural trap that favoured the accumulation and preservation of remains corresponding to individuals from different sources. According to the taphonomic evidence, some individuals (Lagostomus maximus, Lestodelphys halli and Serpentes indet.) died inside the burrow, whereas others (Microcavia australis, Reithrodon auritus and Ctenomys sp.) died outside the burrow, and after a time of being exposed on the surface their remains were transported by surface run-offs into the burrow. The record of Lestodelphys halli and Serpentes indet. in the burrow produced by Lagostomus maximus could be related to a circumstantial use. Mammal burrows are a significant taphonomic mode for the late Cenozoic of the Argentine Pampas

    Cellular Therapy with Engineered T Cells, Efficacy and Side Effects

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    The cellular basis of cancer immune surveillance, already hypothesized in ancient times, was only demonstrated with the advent of HSCT. Indeed, the discovery of the nature of GVHD and its antileukemic effects (Weiden et al
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