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Biomedical subjects

J W Smit

Publications and source records attributed to J W Smit.

104 records · Page 6Linked to original sources
PubMed1983

Fc gamma receptors on lymphocytes from normal donors and patients with lymphoproliferative diseases. Influence of incubation conditions.

The antibody-coated human erythrocyte and the antibody-coated ox erythrocyte rosette assays (EAHu and EAOx) were compared to detect Fc gamma receptors on human peripheral blood lymphocytes. Two incubation conditions were examined: 1 h at room temperature and overnight at 4 degrees C. In healthy persons, in patients with Hodgkin's disease and in patients with non-Hodgkin lymphoma (NHL) the mean percentage of EAHu-rosette-forming cells (EAHu-RFC) increased significantly when the incubation was carried out overnight at 4 degrees C instead of 1 h at room temperature. This increase was caused by Fc gamma receptor-bearing T cells. In the case of EAOx-RFC only a slight increase was found. The percentage of EAHu-RFC and EAOx-RFC differed significantly in the healthy group after the overnight incubation and in the NHL group after the 1-hour incubation. When comparing the mean percentage of EA-RFC in the patient groups with that of the healthy persons significant increases were observed: EAHu-RFC in patients with Hodgkin's disease in the overnight incubation and EAOx-RFC in patients with Hodgkin's disease and NHL in both incubation conditions. In patients with chronic lymphocytic leukemia (CLL, B-cell type) the mean percentage of EAHu-RFC was very low, however that of EAOx-RFC was moderate to high. It is concluded that in the two rosette assays the antigen-antibody complexes may have different avidities to different lymphocyte subpopulations, and that incubation conditions may have an influence on this avidity.

Animals↗
PubMed1982

Parallel tubular structures in T,B and null lymphocyte subpopulations.

T, B and Null lymphocyte-enriched subpopulations were isolated by means of sheep red blood cell (E SRBC) sedimentation and nylon wool adherence. In these subsets the proportion of Fc receptor-bearing cells was determined by the antibody-coated human and ox erythrocyte rosette assays (EA Hu and Ox). In the T-cell fraction the proportion of Fc-bearing lymphocytes was dependent on the procedure by which the sheep erythrocytes were removed from the E SRBC rosette-forming cells. Mechanical vibration resulted in considerably higher percentages of EA rosette-forming cells (EA-RFC) than osmotic shock or lysis with ammonium chloride. In all three procedures the number of EA Hu-RFC was slightly higher than the number of EA Ox-RFC. In the B-cell fraction the proportion of EA Ox-RFC was higher than that of EA Hu-RFC, mean values 43 and 33%, respectively. In the Null cell fraction the reversed was seen: mean values 54% EA Hu-RFC and 45% EA Ox-RFC. In all three lymphocyte fractions the majority of the EA-RFC contained parallel tubular structures and/or associated amorphous granules. Non-Fc receptor-bearing lymphocytes only occasionally showed parallel tubular structures or the amorphous granules.

Animals↗
PubMed1982

Functional properties of T cells in patients with chronic T gamma lymphocytosis and chronic T cell neoplasia.

The expanded T cell populations of 10 patients with either T gamma lymphocytosis (five patients) or proven chronic T cell malignancy (five patients) were analyzed with respect to functional activity in vitro, including proliferative responses to mitogens, cytotoxic activity (killer [K] and natural killer [NK] cell activity), and regulatory activity on pokeweed mitogen- (PWM) induced immunoglobulin (Ig) synthesis (help and suppression) in comparison with marker phenotypes. In each of the five patients with T gamma lymphocytosis, only one out of three functionally distinct cell types was found: T gamma-K cells, T gamma-S cells, or T gamma-NK/K cells, which mediated K-cell activity, suppressive activity, and both NK and K cell activity, respectively. An expanded T gamma-K cell population was demonstrated in three patients with neutropenia with or without recurrent infections. T gamma-S cells were found in a patient with severe hypogammaglobulinemia, and T gamma-NK/K cells in one patient with asymptomatic lymphocytosis. T gamma-K and T gamma-S cells had a similar surface-marker profile (E+ or E-, Fc gamma+, OKT1-3+4-8+I1-M1-), whereas that of T gamma-NK/K cells was different (E+, Fc gamma+, OKT1-3-4-8-I1+M1+). Longitudinal studies of three untreated patients with T gamma-K lymphocytosis showed that the abnormalities were persistent but not progressive. In contrast, five patients with chronic T cell malignancy (two with T-CLL, two with cutaneous T cell lymphoma [CTCL], and one with T-PLL) all had progressive disease. The neoplastic cells in these cases were E+, Fc gamma-OKT1+4+6- with variable expression of the OKT3 and OKT8 markers. The only functional activity observed in these cells was suppressive activity by OKT3-4+8- cells from a patient with CTCL.

Adult↗
PubMed1980

The antiperinuclear factor: II. A light microscopical and immunofluorescence study on the antigenic substrate.

The antigenic substrate of the antiperinuclear factor (APF) in human buccal mucosa cells was studied by light microscopy, cytochemistry, and the immunofluorescence technique (IFT). The cytoplasmic granules against which the APF is directed stained basophilic in light-microscopical staining techniques. The granules did not show a positive reaction product by techniques in which special chemical components are stained, and no activity of lysosomal enzymes could be identified. The use of autoantibodies and other antisera directed to distinct tissues, components, or macromolecules did not resolve the character of the antigenic granules. In addition it was shown that human vaginal epithelial cells and cryostat sections of human and rabbit buccal and oesophageal mucosa incubated with APF-positive sera showed the same fluorescent granules in the IFT as human buccal mucosa cells. Cryostat sections of rabbit buccal and oesophageal mucosa were tested as an alternative substrate in the APF test. Since the specificity as well as the sensitivity decreased when these sections were used as a substrate, they are not suitable for diagnostic purposes.

Adult↗
PubMed1979

A commercially available interactive pattern recognition system for the characterization of blood cells: description of the system, extraction and evaluation of simple geometrical parameters of normal white cells.

A programmable system, the Textur Analyse System (T.A.S.) of E. Leitz, is described for use in interactive work on pattern recognition of white blood cells. The system appears well suited for the task of finding new parameters for the characterization of normal and abnormal blood cells. Hardware advantages such as speed of operation are coupled with software flexibility. The first application of the machine has been the extraction of some of the ordinary parameters for characterization of leucocytes. The value of each parameter has been analysed with the interactive statistical pattern analysis program (ISPAHAN). A separation in the five normal classes of peripheral white blood cells can be achieved, in which the nuclear/cell area ratio and nuclear area together with the density histograms proved to be the most important parameters. The interesting feature of the system is, however, the possibility of finding new data for the recognition of normal and abnormal blood cells.

Computers↗
PubMed1979

The antiperinuclear factor. 1. The diagnostic significance of the antiperinuclear factor for rheumatoid arthritis.

In 1964 Nienhuis and Mandema reported the presence of antibodies against cytoplasmic granules in buccal mucosal cells in the serum of 50% of patients with rheumatoid arthritis (RA). Although they reported a good specificity for RA of these so-called antiperinuclear antibodies (APF), their results never threatened the monopoly of the rheumatoid factor as a serological tool for the diagnosis of RA. A re-evaluation with improved immunofluorescence methods showed a frequency of the APF of 78% in 103 patients with RA. The latex test and the Waaler-Rose test were positive in only 70% and 58% respectively of these patients. Only 15% of the RA patients were negative for all 3 tests. Thus, 40% of patients who were seronegative by the traditional methods gave a positive result on performance of the APF test. The high sensitivity of the APF test was combined with a good specificity, for the frequency in patients with other autoimmune diseases or degenerative joint disease and in healthy subjects was low. For the serodiagnosis of RA it seems best to combine the use of the APF test with one for rheumatoid factor.

Arthritis, Rheumatoid↗
PubMed1979

A biclonal origin of two monoclonal proteins, IgG3(kappa) and IgA1(lambda), from a single patient.

The cellulose acetate electrophoretic pattern of the serum from patient Sik disclosed two distinct peaks, representing two monoclonal proteins. On immunoelectrophoresis the two M-components were found to differ in heavy chain class as well as in light chain type, IgG3(kappa) and IgA1(lambda). Serum immunoglobulin levels remained relatively constant over a period of 7 years and no clinical symptoms of a malignant deterioration occurred. It was found that the isolated M-components did not share idiotypic antigenicity. Bone marrow cells synthesizing the monoclonal proteins were identified by means of the immunofluorescent technique using isotypic as well as idiotypic antisera. Two distinct monoclonal cell populations were observed, containing either the IgG3(kappa) or the IgA1(lambda) monoclonal protein. The alpha 1-chain belonged to the VHIII subgroup, whereas the gamma 3-chain was found to be blocked. Subsequent sequence determination showed the gamma 3-chain to belong to the VHIII subgroup. It was concluded that the two M-components in the serum of patient Sik resulted from two independent neoplastic transformations.

Aged↗
PubMedDate not supplied

Risk of transmission of human immunodeficiency virus (HIV) by heat-treated factor VIII concentrates in patients with severe hemophilia A.

At the change from unheated to heat-treated Factor VIII concentrates for the treatment of hemophilia A, 17 severe adult hemophiliacs (mean monthly dose, 4927 IU) were evaluated prospectively for signs of infection with human immunodeficiency virus (HIV). Viral serology and lymphocyte subpopulations (OKT3, OKT4, and OKT8-positive cells) were examined monthly for 1 year. One patient seroconverted for HIV in the enzyme-linked immunoabsorbent assay but was positive on the Western blot analysis from the outset. There was a slight but significant increase in OKT4+ cells and OKT4/OKT8 ratio. These data suggest that heat-treated Factor VIII concentrates even when used in large amounts have a low risk of transmitting HIV.

Adolescent↗
PubMedDate not supplied

Natural killer cell surface markers on cells containing parallel tubular structures.

Parallel tubular structures (PTS) and/or the associated electron-dense granules, thought to contain molecules responsible for target cell lysis, can be detected in the cytoplasm of lymphocytes with large granular lymphocyte (LGL) morphology. In the present study we compared PTS presence in freshly isolated peripheral blood lymphocytes and peripheral blood lymphocytes incubated overnight in the presence of human pooled serum, sera from patients with Hodgkin's disease and interferon-alpha. Under all conditions we found PTS in the majority of CD16+ cells (64.3-74.8%) but less than 41.8% in CD57+ cells. In the case of double-labeled lymphocytes, 41.0-61.7% CD16+/8+ but only 24.2-27.5% CD57+/8+ cells were PTS+. Thus, in all cases where lymphocytes expressed CD16 antigen there was a high percentage of PTS positivity. Although the PTS+ cells exhibited phenotypic heterogeneity there was, except for a proportion of CD57+ lymphocytes which exhibited less of the characteristic LGL features, generally LGL morphological homogeneity. CD16 lymphocytes are potentially more cytotoxic than CD57 and CD8 cells. Taking this into consideration, the presence of the PTS in the majority of CD16 cells suggests an important role for PTS in target cell lysis.

Antigens, CD↗