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D F Kiszkiss

Publications and source records attributed to D F Kiszkiss.

11 recordsLinked to original sources

Some characteristics of human rosette-forming cells.

Some evidence for identification of human rosette-forming cells as thymus and thymus-dependent lymphocytes (T cells) is presented. Application of the rosette assay to several clinical conditions including primary immunodeficiency diseases indicates the usefulness of this assay in quantitating the number of T cells in peripheral blood.

Animals↗

T Cells in immunodeficiencies as evaluated by an antihuman T-cell serum.

An antihuman T-cell has been prepared in rabbits by infecting lymphocytes from a patient with Bruton-type agammaglobulinemia and absorption with cultured B-lymphoblast cells. Cytotoxicity of the antiserum was assayed with peripheral blood lymphocytes in the presence of rabbit complement and its specificity for T vs B cells was verified. This anti-T-cell serum killed 66% (range 49-78) of normal blood lymphocytes. In patients with Bruton-type agammaglobulinemia the percentage of cells sensitive to the antiserum was above normal (77-89%), whereas it was decreased in some patients with lepromatous leprosy or under antilymphocyte globulin therapy.

Absorption↗

Immunodeficiency in leprosy.

It is known that the impairment of cell-mediated immunity (CM) exists in lepromatous leprosy patients. This was shown by 1) delayed skin reaction to various test antigens, 2) decreased transformation of lymphocytes by various antigens, 3) delayed rejection of skin allograft, 4) decreased migration inhibitory fa-tor (MIF) formation, and 5) histologic study of the lymph node. In addition to these previous works, we have studied T and B lymphocytes in peripheral blood of leprosy patients; T cells by the technic of rosette formation, and B cells by staining surface immunoglobulins. The result of our study shows decreased numbers of T cells and increased numbers of B cells in peripheral blood of lepromatous patients. A the same time, we found that allogenic leukocyte infusion treatment reversed T and B-cell abnormalities. We know that repeated infusions of allogenic leukocytes dramatically brought about improvement of the clinical status of the patients, resolution of skin lesions, subsidence of erythema nodosum leprosum reaction, clearance of bacteria from the skin and lymph nodes, and reconstitution of peripheral lymph nodes.

Agglutination Tests↗

Thymus-dependent lymphocytes of peripheral blood in leprosy patients.

Study of the numbers of thymus-derived lymphocytes by the rosette assay (T-RFC) in patients with leprosy reveals that lower than normal numbers of T-RFC are regularly seen in those patients with the active lepromatous form of this disease. Essentially normal numbers of T-RFC were found in inactive lepromatous, borderline, and indeterminate types of leprosy. The lowest percentages and lowest absolute numbers of T-RFC were encountered in patients with lepromatous leprosy resistant to chemotherapy. Patients with lepromatous leprosy complicated by erythema nodosum leprosum show numbers of T-RFC that are more nearly normal than the numbers of T-RFC in patients with uncomplicated lepromatous leprosy. These findings are discussed with respect to the pathogenesis of lepromatous leprosy and the T-RFC deficiency demonstrated in this disease. The possibility that transient defects in T-RFC numbers or function may predispose to lepromatous leprosy is proposed.

Adult↗

Localization and solubilization of the respiratory nitrate reductase of Bacillus stearothermophilus.

Membranes were isolated from Bacillus stearothermophilus 2184D by lysozyme digestion of the cell wall and subsequent differential centrifugation. Observations with the electron microscope indicate that such membranes are relatively intact and have a typical membrane appearance. Nitrate will preferentially oxidize the cytochrome b of such membranes. Approximately 80% of the total respiratory nitrate reductase activity of whole cells can be localized in the washed membrane fraction and the process of membrane isolation results in a sixfold purification of this enzyme. Of several detergents tested, sodium dodecyl sulfate, Triton 114, and Triton X-100 are most effective in converting reduced methyl viologen-nitrate reductase to a form which will not pellet at 130,000 x g. Density gradient analysis reveals that such detergent-mediated solubilization converts virtually all membrane protein to a form of lighter density.

Acetates↗

Physical aggregation and functional reconstitution of solubilized membranes of Bacillus stearothermophilus.

Isolated membranes of Bacillus stearothermophilus 2184D can be disrupted by treatment with sodium dodecyl sulfate (SDS). This disruption is attended by a decreased turbidity of membrane suspensions and a differential loss of activities of the electron transport system. Reduced methyl viologen (MVH)-nitrate reductase activity is insensitive to SDS treatment, whereas reduced nicotinamide adenine dinucleotide (NADH)-nitrate reductase and cyanide-sensitive NADH oxidase activities are decreased by 80% at an SDS concentration of 0.5 mg/mg of membrane protein. NADH-menadione reductase activity is unaffected at this SDS concentration, but at higher detergent levels it also decreases in activity. The abilities of NADH to reduce and nitrate to oxidize the cytochrome components of the membrane were also decreased after SDS treatment. Dilution of solubilized membrane in buffer containing divalent cation results in formation of an aggregate with an increased turbidity and reconstituted NADH-nitrate reductase and cyanide-sensitive NADH oxidase activities. Of several cations tested, magnesium was the most effective, and the reconstitution process was pH-dependent with an optimum at pH 7.4. Intact and aggregated membranes had similar densities and cytochrome contents, and the sensitivity of NADH-nitrate reductase to several inhibitors was similar in intact and reconstituted membranes.

Bacillus↗

Influence of oxygen on development of nitrate respiration in Bacillus stearothermophilus.

A denitrifying mutant of Bacillus stearothermophilus NCA 2184, strain 2184-D, was used to explore the development of nitrate respiration in relation to oxygen respiration. Aerobically grown wild-type cultures could acquire the ability to use nitrate as a result of selection of nitrate-respiring mutants by the presence of nitrate and a reduced oxygen tension. Fluctuation analysis has revealed that the frequency of occurrence of the nitrate-respiring mutant is about 7.5 x 10(-8) per bacterium per generation. Nitrate reductase and nitrite reductase appeared to be induced sequentially in strain 2184-D by the addition of nitrate. The formation of both of these enzymes was repressed by oxygen so that cells grown aerobically with nitrate possessed a low basal level of nitrate reducatase and exhibited no denitrification. The rate of synthesis of nitrate reductase increased quickly after addition of nitrate and removal of oxygen. It then declined to a lower steady-state level. Cells grown anaerobically with nitrate retained approximately 30 to 40% of the respiratory activity of aerobically grown cells. Aeration of anaerobically grown cells in the presence of amino acids increased the respiratory activity to normal aerobic levels. This aeration promoted rapid degradation of the existing nitrate reductase with or without the added amino acids.

Bacillus↗