Adhesion, Spreading and Fragmentation of Human Megakaryocytes Exposed to Subendothelial Extracellular Matrix: A Scanning Electron Microscopy Study

Platelet agonists and subendothelial extra-cellular matrix (ECM) induce morphological and biochemical changes in animal megakaryocytes, reminiscent of the response of platelets to the same substances. We have examined the behavior of human megakaryocytes exposed for up to 36 hours to the ECM produced by cultured bovine corneal endothelial cells. By phase contrast and scanning electron microscopy these megakaryocytes demonstrated non-reversible adherence and flattening with formation of long filopodia, thus confirming that human megakaryocytes acquire platelet functional capacities. In addition, megakaryocyte fragmentation into prospective platelets was apparently induced by the ECM. Up to 50% of the adherent megakaryocytes underwent spontaneous fragmentation into small particles which individually reacted like platelets on the ECM. The interaction of the megakaryocytes with the ECM was specific since no adherence, flattening or fragmentation occured upon incubation of the megakaryocytes on regular tissue culture plastic or glutaraldehyde fixed ECM. Thus we have demonstrated platelet like behaviour of human megakaryocytes in response to this physiological basement membrane and a possible role of the subendothelium in platelet production which may occur in vivo as megakaryocytes cross the sinusoid walls and enter the blood stream

T-cell project: an international, longitudinal, observational study of patients with aggressive peripheral T-cell lymphoma

Peripheral T-cell lymphomas (PTCLs) comprise a heterogeneous group of neoplasms that are derived from post-thymic lymphoid cells at different stages of differentiation and with different morphological patterns, phenotypes, and clinical presentations. PTCLs are highly diverse, reflecting the diverse cells from which they can originate and are currently sub-classified using World Health Organization (WHO) 2008 criteria. Peripheral T-Cell Lymphomas account for 5%-10% of all lymphoproliferative disorders in the Western hemisphere, with an overall incidence of 0.5-2 per 100,000 individuals per year, and have a striking epidemiological distribution, with higher incidence in Asia. The clinical features of PTCL are extremely heterogeneous. PTCLs express even more clinical diversity than B-cell non-Hodgkin's lymphomas, and there is a close, though not absolute, relationship between some unusual clinical features and certain histological subtypes

Predictive value of the CLL-IPI in CLL patients receiving chemo-immunotherapy as first-line treatment

An international collaboration has led to the development of a comprehensive tool [CLL-IPI international prognostic index for CLL] for the predicting of overall survival (OS) in chronic lymphocytic leukemia (CLL).1 CLL-IPI was based on data collected from 3500 CLL patients and was based on the following parameters: TP53 deletion and/or mutation, IGHV mutational status, \u3b22-microglobulin plasma levels, clinical stage, and age. CLL-IPI provides the means to stratify CLL patients in the daily clinical practice (Supplementary Table 1).1 Although validated for OS2-4 and time to first treatment (TTFT),5 the predictive value of CLL-IPI on progression-free survival (PFS) has until now only been demonstrated in a single study on patients treated with chlorambucil (CLB), as monotherapy, or in combination with obinutuzumab or rituximab, as a first-line approach (CLL11 study),6 and presented as a poster at the annual meeting of the American Society of Hematology (ASH) in 2016

Soluble CD52 is an indicator of disease activity in chronic lymphocytic leukemia

Biological, physical and clinical aspects of cancer treatment with ionising radiatio