The effect of ethanol on histone glycation in diabetic rats.

The glycation of liver histones was studied in rats with streptozotocin-induced diabetes, in ethanol (EtOH)-treated rats, and in EtOH-treated diabetic rats. In diabetes, the conditions of glucose-protein addition are more favourable extracellularly in serum and in erythrocytes than in the nucleus. This is indicated by the increased level of serum fructosamine and by the high level of glycated haemoglobin, while the glycation of intracellular histone is decreased. In the serum of diabetic rats, we found a relatively high acetaldehyde level, which resulted in elevated histone fluorescence. Fluorescence is an accepted marker of advanced glycation end-product (AGE), the intensity of which, according to our experiments is related not to the level of serum glucose, but to the level of acetaldehyde. The data obtained with histone proteins in diabetic rats treated with EtOH are in good agreement with the results of our earlier in vitro experimental results obtained with H1 histone: the reaction of the two aldehydes (glucose and acetaldehyde) in combination gives a lower glycohistone value than they do separately.

Expression of an adhesion molecule and homing in B-cell chronic lymphocytic leukaemia: I. Application of the HEV-binding assay to a clinical series.

High endothelial venule (HEV)-binding of peripheral blood mononuclear cells (PBMCs) from 43 patients with B-cell chronic lymphocytic leukaemia (B-CLL) was investigated with a HEV-binding in vitro assay. Immunophenotyping of HEV-adherent PBMCs proved that most of them belonged to the B-cell proliferation. B-CLL cells stringently expressed CD44 molecules (Hermes-1, -3 and H90). The patients were subgrouped according to Binet's classification, as well as according to the organ manifestations, i.e. patients with B-cell monoclonal lymphocytosis of undetermined significance (B-MLUS) and patients with lymphocytosis (LY), lymph node enlargement (LN) and splenomegaly (SM). The HEV-binding activity of the cells was the highest in Binet stage A patients and in patients with B-MLUS (p < 0.05 in B-MLUS versus B-CLL LY, LN, SM). Based on these findings it is suggested that B-CLL patients show not only a clinical and immunophenotypical heterogeneity, but a diverse function of adhesion molecules.

Blood vessels in human immunodeficiency virus-related lymphoadenopathy: high endothelial venules and lymphocyte migration.

The vasculature of 25 lymph nodes of patients with human immunodeficiency virus-related lymphadenopathy was investigated morphometrically. The number of small vessels, the morphological features of high endothelial venules and the migratory index of the lymphocytes passing through the high endothelial venules, as well as the stage-dependent change of each parameter, were analysed. Twenty reactive lymph nodes served as controls. The total number of vessels in the HIV-infected lymph nodes was relatively stable. However, the small vessels with flat endothelium increased in number, while the number of high endothelial venules decreased as the disorder progressed, and the decrease in the lymphocyte migration seemed to precede the change in the morphology of high endothelial venules. The presumptive role of these alterations in the pathogenesis of the investigated disorder is emphasized.

Antigen-induced changes in the lymphocyte-high endothelial venule interaction.

The sequential changes of some morphometric parameters (lymph node weight, high endothelial venule (HEV)-content) after an antigenic challenge (sheep red blood cell; SRBC) and the alterations of HEV-function (HEV-adhesiveness measured with a HEV binding assay) were studied in rat lymph nodes over a period of seven days with daily measurements. Authors suggest that the proper estimation of the HEV-content of a lymph node in a HEV binding assay allows to express the HEV-adhesiveness numerically, and to compare the data obtained by this assay quantitatively. The HEV-adhesiveness is the strongest on day 6 after the antigenic challenge, the early increase in weight on day 2 is attributed to an increased blood flow and the changes in the HEV-content are presumed to reflect a simple dilation of HEVs (on day 2) and later (on days 4 and 5) an increase in the height of high endothelial (HE) cells. A crucial role is ascribed to the altered HEV-adhesiveness in the increase of lymphocyte migration to the challenged lymph nodes.

Antigen-induced changes in the lymphocyte-high endothelial venule interaction.

The sequentional changes of some morphometric parameters (lymph node weight, high endothelial venule (HEV)-content) after an antigenic challenge (sheep red blood cell; SRBC) and the alterations of HEV-function (HEV-adhesiveness measured with a HEV binding assay) were studied in rat lymph nodes over a period of seven days with daily measurements. Authors suggest that the proper estimation of the HEV-content of a lymph node in a HEV binding assay allows to express the HEV-adhesiveness numerically, and to compare the data obtained by this assay quantitatively. The HEV-adhesiveness is the strongest on day 6 after the antigenic challenge, the early increase in weight on day 2 is attributed to an increased blood flow and the changes in the HEV-content are presumed to reflect a simple dilation of HEVs (on day 2) and later (on days 4 and 5) an increase in the height of high endothelial (HE) cells. A crucial role is ascribed to the altered HEV-adhesiveness in the increase of lymphocyte migration to the challenged lymph nodes.

High endothelial venules in B-cell non-Hodgkin malignant lymphomas.

The number of high endothelial venules (HEVs) per unit area was determined in 55 B-cell non-Hodgkin malignant lymphomas (nHMLs) classified according to the Kiel classification. The number of HEVs per unit area was significantly different between low- and high-grade B-cell nHMLs. In the low-grade group, a large number of HEVs with preserved structure were present, whereas in high-grade tumours the HEVs appeared damaged. The present findings support the previous observation attributing prognostic relevance to lymphocyte recirculation in nHMLs.

The pathomorphological diagnosis of acute leukaemias: cytology, cytochemistry and immunocytology.

In 74 cases of acute leukaemia and of the blastic phase of chronic granulocytic leukaemia (CML), monoclonal antibodies of the "VI" series and a few commercially available antibodies proved to be of valuable help in establishing a definite diagnosis. In 4 out of 35 cases of AML (FAB-M 1-5), and in 2 out of 16 of the blastic phase of CML only the use of monoclonal antibodies secured the diagnosis. In the group of acute lymphoid leukaemias subtypes corresponding to various levels of differentiation, were defined. The blasts of 3 patients out of the 74 did not express any of the markers studied. Two additional cases were investigated for platelet peroxidase and studied with the antiplatelet antibodies VIPL 1, 2 and 3 by the electron microscope. These cases proved to be acute megakaryoblastic leukaemias (acute myelofibrosis).

Endothelial cell receptors on leukemic plasma cells.

The binding of peripheral blood mononuclear cells of 7 patients with plasma cell leukemia to rat lymph node high endothelial venules has been studied in vitro. The mononuclear cells adhered selectively to the high endothelial venules. Their neoplastic origin was proved by in situ demonstration of their monoclonal cytoplasmic immunoglobulins. The in vitro binding of bone marrow mononuclear cells of 4 patients with multiple myeloma to high endothelial venules was also studied. In two patients there was no high endothelial cell binding. In the two others some adhering cells were observed. The plasmacytoid nature of these cells was, however, excluded for lack of cytoplasmic immunoglobulins. Since cells at the end stage of B-cell differentiation lose their surface receptors associated with lymphocyte recirculation, the presence of endothelium-recognizing structures on leukemic plasma cells seems to be remarkable.

[Morphology and cytodynamics of oxazolone-induced cellular immune response]. / Az oxazolon által kovaltott celluláris immunválasz morfológiája és citodinamikája.

Dynamics of lymphoid tissue changes induced by oxazolone, a contact allergen responsible for immune reaction of delayed type was studied. Basing on light-and electron microscopic findings and morphometrical analysis the following components of the reaction may be distinguished: an early active lymphocytic migration, a delayed paracortex proliferation and a following follicular response. In the regulation of the outflow of lymphocytes a primary role may be attributed to the endothelial lining of the postcapillary venules. For the morphological changes of endothelial cells an effect of circulating antigen specific lymphocytes may be responsible.