Surgical treatment of a primary cardiac lymphoma presenting with tamponade physiology

Primary cardiac lymphomas (PCL) are rare cardiac neoplasms that carry an ominous prognosis. They occur more frequently in immunocompromised patients. We report on an immunocompetent 67-year-old who presented with dyspnea and dysphagia. Echocardiographic evidence of impending cardiac tamponade and obstruction of the inferior vena cava (IVC) with the tumor was seen. The deteriorating hemodynamics of our patient prompted an urgent surgical intervention. Pathohistological diagnosis showed diffuse large B-cell lymphoma of centroblastic subtype. Chemotherapy remains the standard treatment of PCL, with surgery reserved for relieving life-threatening complications of the neoplasm.     

Continuous- and semicontinuous-flow blood centrifugation systems: therapeutic applications, with plasma-, platelet, lympha-, and eosinapheresis

Blood centrifugation, with a continuous-flow or semicontinuous-flow system, was used in the treatment of 17 patients with various hematologic disorders. Total plasma exchange (TPE) controlled symptoms of hyperviscosity and arrested bleeding in three patients. In two patients, TPE made is possible to perform urgent surgical procedures. It was a very valuable adjuvant in the treatment of one patient with a Factor VIII inhibitor. Eosinapheresis was not of significant value in the therapy of syndromes associated with eosinophilia. Lymphapheresis significantly reduced peripheral lymphocytosis, aiding in the chemotherapeutic control of chronic lymphosarcoma cell leukemia in one patient. It was of questionable value in the maintenance therapy of two patients with Sezary syndrome. Plateletapheresis significantly reduced peripheral platelet count in thrombocytosis, making it possible to minimize the chemotherapeutic dose and permitting urgent surgical procedures in two patients.     

Immunolocalization of nestin, mesothelin and epithelial membrane antigen (EMA) in developing and adult serous membranes and mesotheliomas

The spatial and temporal distribution of epithelial membrane antigen (EMA), mesothelin and nestin was immunohistochemically analyzed in developing and adult human serous membranes and mesotheliomas in order to detect possible differences in the course of mesenchymal to epithelial transformation, which is associated with differentiation of mesothelial cells during normal development and tumorigenesis. Pleura and pericardium developing from the visceral mesoderm gradually transform into mesothelial cells and connective tissue. EMA appeared in mesothelium of both serous membranes during the early fetal period, whereas during further development, EMA expression was retained only in the pericardial mesothelium. It increased in both pleural mesothelium and connective tissue. Mesothelin appeared first in pericardial submesothelial cells and later in surface mesothelium, while in pleura it was immediately localized in mesothelium. In adult serous membranes, EMA and mesothelin were predominantly expressed in mesothelium. Nestin never appeared in mesothelium, but in connective tissues and myocardial cells and subsequently decreased during development, apart from in the walls of blood vessels. Mesothelial cells in the two serous membranes developed in two separate developmental pathways. We speculate that submesothelial pericardial and mesothelial pleural cells might belong to a population of stem cells. In epithelioid mesotheliomas, 13% of cells expressed nestin, 39% EMA and 7% mesothelin.     

The interaction of TIGIT with PVR and PVRL2 inhibits human NK cell cytotoxicity

NK cell cytotoxicity is controlled by numerous NK inhibitory and activating receptors. Most of the inhibitory receptors bind MHC class I proteins and are expressed in a variegated fashion. It was recently shown that TIGIT, a new protein expressed by T and NK cells binds to PVR and PVR-like receptors and inhibits T cell activity indirectly through the manipulation of DC activity. Here, we show that TIGIT is expressed by all human NK cells, that it binds PVR and PVRL2 but not PVRL3 and that it inhibits NK cytotoxicity directly through its ITIM. Finally, we show that TIGIT counter inhibits the NK-mediated killing of tumor cells and protects normal cells from NK-mediated cytoxicity thus providing an “alternative self” mechanism for MHC class I inhibition.