Allergie und Immunologie最新文献

Mice (BALB/c or ICR) were infected with Schistosoma mansoni cercariae. After different intervals (mostly eight weeks) the following antigens were injected: a) sheep erythrocytes--b) DNP-thyroglobulin. Afterwards the immune response against these antigens were checked by means of different methods (plaque assay, haemagglutination test, rosette technique). Immune responses to these antigens were depressed in all cases compared to age matched uninfected mice but it was not possible to transfer this immunosuppression with spleen cells to normal or to irradiated recipients.

In the spring of 1986, the pollen were collected from apple trees in full blossom, and were investigated for their allergenicity. The patients selected for study were subjects with a combined inhalant allergy to birch pollen and an oral allergy to apple fruit. The apple pollen extract yielded about the same percentage of nondialysable substance as obtained from birch pollen. In contrast to the latter, UV-spectroscopy revealed no flavonoids adsorbed to the apple pollen proteins. Patients with a combined allergy to birch pollen and apple fruit showed positive skin reactions to both birch and apple pollen extract. Inhibition of IgE-binding in RAST to birch pollen was observed by apple pollen extract at a 1000-fold lower potency than the homologous birch allergens. Immunoblotting demonstrated IgG-antibodies in birch-allergic sera cross-reactive with apple pollen components. It is concluded that minor allergenic determinants cross-reactive with birch pollen epitopes occur not only in the fruit, but also in the pollen of the apple tree.

Human monoclonal antibodies were tested using different immunochemical procedures for their reactivity with various antigens. The great majority of human monoclonal IgM antibodies (15 out of 24) turned out to bind to a whole series of recognized antigens (DNA, keratin, tetanus toxin, ricin etc.). The specificity of these reactions was detected by competitive assays. For some antibodies a simultaneous reaction with two antigens could be demonstrated by capture bridge technique. IgG antibodies also turned out to be multireactive, but not to the same extent (range of antigens much smaller, only 5-6 out of 53).

Non-specific complications are encountered relatively often in patients with below normal granulocytic phagocytosis rates. We tested vitamin C, transfer factor, gamma-globulin, BCG, PPD, UV irradiation of the subject's blood (UVB) and hyaluronidase with the aim of stimulating granulocytic phagocytosis with rice starch in autologous serum. In our experiments, only the addition of hyaluronidase caused any increase in phagocytotic activity. The in vitro experiments with hyaluronidase yielded promising results and will be followed up since they may be relevant to practical questions.

Treatment of mice bearing allogeneic tail skin grafts with iloprost, a stabilized prostacyclin derivative, as well as dexamethasone prolonged graft survival. Nalador and flunoprost, stabilized prostaglandin E analogues, had similar but weaker effects. The thromboxane agonist U 46619 had no effect on graft rejection. An incubation of human monocytes with iloprost or prostaglandin E2 led to a dose-dependent reduction of HLA-DR antigen expression by these cells. Furthermore, a suppressive effect of these prostaglandin derivatives on the calcium ionophore stimulated release of arachidonic acid metabolites by human polymorphonuclear leukocytes has been shown, which demonstrates an antiinflammatory action of these drugs. Additionally, the eicosanoids were determined in the tail skin after complete allograft rejection. The importance of thromboxane for the rejection of skin grafts has not been confirmed. These data, along with the known antiaggregatory and antiischemic cytoprotective effects of iloprost, suggest that this newly developed drug may be all the more important in clinical organ transplantation.

Monoclonal antibodies against different non-polymorphic determinants of HLA class II antigens are described. The epitopes are present on HLA-DR and HLA-DQ gene products as detected by monoclonal antibody BL-Ia/l, and at HLA-DR and HLA-DP gene products which are recognized by monoclonal antibody BL-Ia/4. Another epitope recognized by the monoclonal antibody BL-Ia/DQ is only found on DQ molecules. The monoclonal antibodies BL-Ia/1, BL-Ia/4, and BL-Ia/5 are directed against the beta-subunit of 29 kDa/35 kDa class II heterodimer molecules. The recognized epitopes are shown to be not dependent on the association of the alpha- and beta-chains.

Sera from 251 children living in endemic areas (Schistosoma mansoni or Schistosoma haematobium) and from 188 hospital outpatients in Ethiopia were evaluated for specific IgG4 antibodies reacting with Schistosoma mansoni adult worm antigen employing an enzyme-immunoassay. Patients with schistosomiasis (n = 140) possessed a significantly higher mean value of specific IgG4 antibodies than normal controls (n = 30) and individuals from different countries who had no schistosomiasis but are infected with other parasites (n = 114). Blood samples dried on filter paper were also acceptable in these test. The use of the test in diagnosis is compared and assessed with parasitological methods.

Sera from patients with chronic schistosomiasis (Schistosoma mansoni or Schistosoma haematobium) were examined for the presence of parasite specific IgE antibodies by means of ELISA technique using tegument antigen prepared from adult worms of Schistosoma mansoni and using the monoclonal antibody BL-IgE 9. Individuals from tropical countries who had no schistosomiasis and blood donors from GDR were studied for comparison. Significantly higher levels of specific IgE antibody were given by sera from patients with schistosomiasis than by the controls. These differential responses serologically differentiated between patients with chronic schistosome infections and noninfected individuals.

Using an in vitro microassay (phagocytosis of cadmium microcrystals saturated with human serum albumin) the phagocytic activity of human milk macrophages and glass-adherent blood leukocytes, obtained from healthy adult women and physiological neonates, was compared. It was established that the early milk contains lower percentage of glass-adherent phagocytes than peripheral blood and, in addition, their phagocytic activity, i.e. the mean number of particles engulfed per cell, was significantly lower as compared to blood leukocytes of adult women and newborns.

Studies were undertaken to evaluate immunomodulating properties of Hepatitis B virus (HBV) preparations: HBsAg, HBeAg and their complexes: HBsAg-IgG and HBeAg-IgG, on PHA-induced lymphocyte proliferation. Cells were obtained from blood of healthy individuals, serologically negative for HBV markers. HBV preparations were purified from sera of children with HBV-mediated glomerulonephritis. Suppression of lymphocyte proliferation observed in the presence of HBsAg and HBsAg-IgG complexes was irreversible. However, the suppressive effect of HBeAg and HBeAg-IgG was abolished when these preparations were removed from the culture. Addition of exogenous interleukin-2/IL-2/reversed only the suppressive effect of HBeAg-IgG which was constantly present in the culture. The inhibition of lymphocyte proliferation correlated well with the decreased level of IL-2 activity in cultures with HBV-preparations. Experiments performed using ultracentrifugation indicated that HBV preparations, especially HBsAg and HBsAg-IgG, may bind to IL-2 and inactivate it in supernatants. The experiments indicate that HBV antigens, as well as other viral products, can inhibit lymphocyte proliferative response to the mitogen. Furthermore, we suggest that this inhibition may occur via suppression of IL-2 synthesis.