Allergie und Immunologie最新文献

An enzyme-linked immunosorbent assay using polyclonal antibodies from rabbits has been developed for quantification of Acinetobacter calcoaceticus. Bacteria were added to the wells of a microtiter plate coated with anti-Acinetobacter immunoglobulin. For detecting bound cells the peroxidase-labelled immunoglobulin fraction was used. Over a distinct range there is a linear correlation between bound bacteria and measured absorbance allowing a quantification of bacteria in an order from 10(7) to 10(8) per milliliter. The specificity of the assay was evaluated by the heterologous bacteria Pseudomonas putida, Pseudomonas aeruginosa, Proteus vulgaris, Escherichia coli and Citrobacter freundii. Only a minimal cross-reactivity was observed. Within a certain range of error it is possible to quantitate Acinetobacter calcoaceticus in mixtures with one or several other bacterial species. Mixed with bacteria of one other species the differences to the value for Acinetobacter calcoaceticus alone do not exceed +/- 10% with a tendency to lower values. Mixed with several other species only negative differences up to -15% were obtained. Treatment of Acinetobacter calcoaceticus with 0.5% formaldehyde results in a loss of reactivity up to 15%. In conclusion, the enzyme-linked immunosorbent assay is a useful method for quantitating bacteria not only with respect to the high sensitivity, specificity and good reproducibility but also for the minimal technical equipment and the short assay time.

Activated granulocytes play an important role in propagation of the inflammatory response by production of reactive oxygen species and release of their granule content. Hyperactivation of these cells is suggested to result in deterioration of wound healing and, probably, increase of cicatrization. Pantothenic acid and its stable salt form, Ca-Panthotenate, were shown to significantly improve surgical wound healing. Therefore, in the present study the modulating effect of Ca-pantothenic acid to subsequent stimulation with a variety of stimuli was investigated on isolated human PMN using functional assay systems: Lucigenin-dependent chemiluminescence (CL), release of myeloperoxidase (MPO). Ca-Panthotenate significantly inhibited the CL response of PMN upon stimulation with the chemotactic petide f-met-leu-phe, the tumor promotor PMA, and the granulocyte activating cytokines GM-CSF and TNF alpha at a concentration range of 5 to 50 mM, but not upon stimulation with opsonized zymosan. Moreover, Ca-Panthotenate significantly inhibited the release of myeloperoxidase from PMN upon stimulation with f-met-leu-phe at a concentration of 5 mM. In contrast, Ca-Panthotenate did not directly activate PMN in the assay systems tested. These in vitro results support the concept of an anti-inflammatory action of Ca-Panthotenate in vivo.

A simple procedure for the production of pure monoclonal antibodies (mab) in dialysis tubing has been used. Hybridomas which produce pancreatic islet cell reactive monoclonal antibodies were grown in dialysis tubing containing serum free medium. The dialysis tubing was inserted into a flask with medium containing 7.5% foetal calf serum. The flask was placed on a roller and medium was changed every two days. The optimal time for harvesting the mab could be shown to be after 10 days of culture with a 4 fold increased immunoglobulin concentration in comparison to a conventional hybridoma culture. Immunoglobulin concentrations up to 110 mg/l and cell yields of 1.3 x 10(6)/ml have been obtained. The low concentration of contaminating low molecular weight proteins in the supernatant facilitated or saved purification of mab.

The role of AC at the beginning of an immune response is not fully understood until now. Using the specific substrate AMP-PNP we could show AC-activity in ConA-stimulated murine spleen lymphocytes histochemically. In contrast to beta-adrenergic stimulation (by Isoproterenol) ConA-induced AC-activity was found not only at the cell membrane and the nuclear membrane but also at some structures of the Golgi apparatus of the cells. The difference in AC-activity after beta-adrenergic or mitogenic stimulation is discussed.

Hymenoptera venom allergy is relatively rare in childhood. In 59 children, aged 2-16 years, with a systemic allergic reaction we could detect the following findings: There was no difference between males and females. Relatives of these children had more atopic diseases than normals. The degree of clinical manifestation was not so pronounced as in adults. RAST was more sensitive in detecting bee venom allergy whereas intradermal test showed a higher sensitive in wasp venom allergy. The diagnostic value of prick test was low without any obvious reason.

The effect of IgG as a ligand for Fc gamma receptors on the sheep erythrocytes induced synthesis of IgM and IgG antibodies was studied. The IgG preparations used in these experiments had different effects depending on their IgG1 content. The effects on a primary or secondary induced synthesis of antibodies was not comparable. The IgG preparations were effective in monomeric as well as in aggregated form.

Between 1980 and 1986 465 cadaveric kidney transplants were performed at the Kidney Transplant Centre Berlin-Friedrichshain. The post-transplant risk to acquire a cytomegalovirus (CMV) infection depended on the preoperative CMV antibody status of donor and recipient, on the nettoimmunosuppression and on the recipient's age. The highest infection rate and the most serious courses showed seronegative recipients from seropositive donors. The typical time interval of clinical manifestation included the postoperative months 1-3. A significant dependence of the frequency of infection on different immunosuppressive protocols could not be proven. But there was a significant coincidence between CMV infection and rejection crises. In spite of the raised frequency of rejection crises an influence of the CMV infection on the 1-year-graft and patient survival rates could not be demonstrated. Both an early diagnosis and an adequate therapy are of particular importance.

The mab BL-TSub/2 binds to a majority (80%) of thymocytes. The antigen isolated from these cells has an apparent molecular weight of about 170 kDa. The mab BL-TSub/2 recognized antigen is expressed on approximately 50% of mature T cells in peripheral blood. The mab BL-TSub/2 does not bind to monocytes, granulocytes, platelets and CD16+NK cells. The antigen is possibly present on a part of peripheral B cells in very low density. Double labelling experiments showed that about 30% of CD4+ and 60% of CD8+ cells react with the mab BL-TSub/2. This BL-TSub/2+ subset is not identical with T-cell subpopulations till now defined. Within the CD4+ subset the majority of BL-TSub/2+ cells is included in the CD45RO+ subset while only a small proportion is CD45RA+. However, the CD8+ BL-TSub/2+ cells are mostly CD45RA+ with only few cells belonging to the CD45RO+ subset.

Luminol-enhanced chemiluminescence (LECL) was used to determine the effect of soluble CD14 (sCD14) on the endotoxin inducible generation of reactive oxygen species in human monocytes. LPS is unable to activate monocytes under serum free conditions, but LECL responses were measured after pretreatment of LPS stock solution with serum, according to Wright et al., who described a LPS-binding protein (LBP), necessary for mediating LPS binding to the receptor CD14 on monocyte surfaces. In normal human serum a soluble form of CD14 (sCD14) exists, from which nothing is known about its possible function. sCD14 reduces the endotoxin inducible monocyte activation in our in vitro model in a dose dependent manner (5-30 micrograms/ml) suggesting an immunomodulatory function. Therefore it seems to be a new candidate for a therapeutic concept in endotoxic shock prevention.

Natural history of hymenoptera sting allergy is less life threatening in children than in adults. We evaluated a commonly used risk score (allergic reaction to the index sitting, sensitization measured by skin prick test and specific IgE, and specific IgG - maximal 8 points) for its predictability of forthcoming allergic reactions. 93 children with low scores (less than 7 points) experienced stings in field, 96% were save from severe systemic reactions. Of 119 children with high scores (greater than 6 points) receiving rush hyposensitization only 32% developed systemic reactions. We conclude that the score appropriately identifies individuals not to be hyposensitized, but that it overestimates the number of children with a need for hyposensitization. We therefore developed a diagnostic scheme including challenge stings to identify those children who really need hyposensitization.