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Meristems were excised from young and 8-month-old Kalanchoë blossfeldiana naturally-infected with Erwinia chrysanthemi (Echr). From heavily infected plants the bacteria were identified in meristems from the very top of the plant as well as from meristems situated lower on the plant. In other naturally-infected plants Echr was only found at the stem base, depending on how advanced (old) the infection was. Repetition of identification on meristem samples stored in the refrigerator for 1 week revealed more positive samples than in the first test. Infection trials showed a quick spread of bacteria from stem base to apex via xylem vessels in some of the inoculated plants. Spread of Echr via capillary mats from inoculated to non-inoculated Kalanchoë plants were found after 5.5 months growth on the capillary mat. The time lapse before transmission may vary with the seasons of the year. [ABSTRACT FROM AUTHOR]

Natural killer (NK) cell activity and blood mononuclear cell subpopulations were characterized in patients with Hashimoto's thyroiditis (n= 11), Graves disease (n = 20), non-toxic goitre (n = 10) and in normal controls (n = 22). NK cell activity against K 562 target cells and the capability of IFN-α, II-2, and indomethacin to enhance NK cell activity in vitro did not differ significantly between the groups. The percentages of large granular lymphocytes, CD5 + , CD4 + , CD8 + and CD16 + cells were normal in patients with foil-toxic goitre. Hashimoto`s and Graves' diseases. There was no correlation between NK cell activities and TgAb, MAb and TSAb. Although NK cell activity is suppressed in several autoimmune diseases, NK cell function is normal in patients with autoimmune thyroid disorders. [ABSTRACT FROM AUTHOR]

The incidence of lymphocytic thyroiditis (LT) has increased since the introduction of iodine prophylaxis, and LT is claimed to represent an adverse reaction to iodine. This theory is supported by animal studies as well as experimental studies in humans. In pregnancy iodine turnover is increased. During the immunological rebound period occurring postpartum the thyroid autoantibodies increase, and may lead to postpartum thyroiditis (PPT). The iodine content within the gland may be important for this reaction. In vitro it has been shown that iodine inhibits the cAMP-dependent events of the thyroid cell function, but iodine may also stimulate the intrathyroidal immuno-competent cells leading to cytokine synthesis. Cytokines have been shown to interfere with the thyroid cell function. Iodine may thus trigger the autoreactive attack and enhance the local autoantibody production, which plays a primary pathogenic role for development of PPT. [ABSTRACT FROM AUTHOR]

Cytokines are peptide hormones essential for cellular communication in the immune response. The purpose of this study was to investigate the influence of cytokines, especially recombinant interleukin 1 β (rIL-1β ), on human thyroid cells. Thyroglobulin (Tg) was measured by a double antibody radioimmunoassay, and cyclie AMP (camp) by a competitive protein binding assay, Supernatants from unstimulated and phytohaemagglutinin-stimulated blood mononuclear cells were added to human thyroid cells cultured in monolayers. A dose-dependent inhibition of the secretion of Tg and camp secretion, while at physiological levels (10-1-10-2 U/ml) exhibited an inhibition of Tg and cAMP secretion, while at physiological levels (10-5-10-3 U/ml), the secretion of Tg was enhanced. The similar stimulation of camp was demonstrated in subcultures. These in vitro studies suggest that IL-1β may play a role in the pathogenesis of autoimmune thyroid diseases. Further, the stimulations at low concentrations indicate that IL-1β may regulate the function of the thyroid gland under physiological conditions. [ABSTRACT FROM AUTHOR]

Four allergologically important fungi, viz. Aspergillus fumigatus, Penicillium nolatum, Alternaria altemata, and Cladosporium herbarum were cultured in a liquid synthetic me with or without addition of 0.1 % yeast extract (YE). After 10 and 28 days of cultivation, immunochemical properties of the fungal extracts, characterised by precipitation pattern and IgG- and IgE-binding capacity, were studied. In pure synthetic medium no large differences were observed in number of precipitates, as measured by DID, among the four antigenic fractions of each fungus (metabolic and mycelial antigens of both early and late phase cultures). Addition of YE to the growth medium hardly changed the number of precipitates and generally caused a decrease in IgG-binding capacity of the extracts. In contrast to these observations were the findings with the IgE-binding capacities of the fungal extracts as measured by RAST. Most allergenic fractions demonstrated an increase (sometimes strong) in IgE-binding capacity after YE was added to the growth medium. It is concluded that the time of cultivation influences the immunochemical characteristics of fungal extracts and that mycelial as well as metabolic antigens of both early and late phase cultures should be used in order to obtain a wide spectrum of allergens in extracts used for diagnostic purposes. [ABSTRACT FROM AUTHOR]

Circulating immune complexes (IC) were determined in sera from 41 patients with Hashimoto's thyroiditis by a polyclonal rheumatoid factor (pRF) assay based on the inhibition of the agglutination of IgG-coated latex particles. Elevated levels of IC were found in 63% (26/41) of the sera. There was a significant correlation (Rho = 0.91, P< 0.001) between results obtained before and after treatment of sera with dithiothreitol (DTT). By precipitation with 2.5% polyethylene glycol (PEG) before pRF inhibition assay, the activity of IC was found in only 7% (3/41) of the sera. Size chromatography studies of the sera showed the inhibitory activity predominantly in the intermediary region. When found in the IgM-region the activity was not reduced by DTT. By use of a polyethylene glycol complement consumption test (PEG-CC) the occurrence of IC was 10% (4/41). It was not possible to find any correlation between the detectable IC and the presence of microsomal, thyroglobulin, or thyroid-stimulating antibodies. Based on our studies the sizes of IC seemed to be heterogeneously distributed and the majority were not precipitated by PEG (2.5%), final concentration). The antibodies involved in the formation of complexes seemed to be of IgG or IgA classes. HLA-D typing of the patients showed a non-significant association between HLA-Dw5 and low levels of IC while the presence of HLA-Dw4 was significantly associated with a high level of IC (P< 0.05). [ABSTRACT FROM AUTHOR]

Recently, it has been suggested that in some patients with autoimmune thyroid diseases the tanned red cell (TRC) method for detection of thyroglobulin autoantibodies (TgAb) is negative where TgAb measured by radioimmunoassay (RIA) show positive values. In investigate this further, patients with thyroid diseases, pernicious anaemia and a control group were studied for serum concentrations of TgAb by TRC and by quantitative RIA, calibrated against MRC Standard A65/93. Antibodies for microsomes (MAb) were measured immunofluoretically. There was in all patient groups (Hashimoto's thyroiditis (n = 41). Graves' disease (n = 50), idiopathic myxoedema (n = 12), euthyroid Graves' disease (n = 7), pernicious anaemia (n = 81)) a discrepancy between TgAb measured by TRC and RIA, respectively, whereas there was a reasonable correlation between the presence of TgAb by RIA and the presence of MAb. A possible interference horn antinuclear antibodies and rheumatoid factors was ruled out. There was no increased frequency TgAN measured by RIA in the control group. Fractionation of TRC negative sera revealed macromolecular TRC-activity, whereas TgAb positive sera by both methods had almost exclusively RIA and TRC activity corresponding to IgG. Based on these results and others it seems that the TRC method for measurement of serum TgAb is of limited diagnostic value. Furthermore, the TRC method is in many cases not sensitive enough for screening for TgAb prior to measurement of serum Tg, which is of importance as this method shows false values in tile presence of TgAb due to methodological interference. [ABSTRACT FROM AUTHOR]