International archives of allergy and applied immunology最新文献

[125I]-cyanopindolol (ICYP) was used in a binding assay to compare the number and affinity of beta 2-adrenoceptor binding sites on circulating polymorphonuclear leukocytes (PMN) of 21 children with atopic dermatitis (AD) and 23 age-matched controls. We found no correlation between the beta 2-adrenoceptor density and the age of the children in either collective. Furthermore, the number and affinity of beta 2-adrenoceptor binding sites on PMN was neither influenced by sex nor severity of disease, serum IgE level or percentage of eosinophils in the differential blood count. There was a tendency towards a lower number of beta 2-adrenoceptors in AD subjects (1,429 +/- 587 receptors/PMN) compared to controls (1,753 +/- 596 receptors/PMN), but this difference was statistically not significant.

A cDNA library corresponding to mite protein was screened employing anti-Der f II antibody. Two possible clones containing plasmids pFL1 and pFL11 were obtained. The two plasmids had insertions of about 500 basepairs. The DNA sequences of the two insertions were determined, from which the amino acid sequences were deduced. The amino acid sequence of the purified native Der f II protein could be determined to 45 residues from the N terminus. As a result of comparison, we concluded that the cDNAs prepared from live Dermatophagoides farinae mite corresponded to the mite allergen Der f II. The recombinant Der f II was biologically active.

Experiments in vitro have suggested that IL5 is a late-acting factor in eosinophil production, and that other factors such as IL3, G-CSF and GM-CSF are required for the production of committed eosinophil progenitors. Furthermore, work in vitro indicates that in addition to IL5, both IL3 and GM-CSF are capable of stimulating eosinophil differentiation. Thus, there would appear to be both considerable redundancy in cytokine actions in eosinophilia as well as a complex network of cytokine activities to induce eosinophilia. Experiments in vivo, however, suggest a less complicated control mechanism, dominated by IL5.

Two-dimensional (crossed) immunoelectrophoresis was used for analysis of soluble antigen extracts obtained from the three developmental stages, cercariae, adult worms and eggs, of Schistosoma mansoni by using homologous hyperimmune sera produced in sheep. The antigenic relationships between the three stages as well as the possible relationship to the intermediate snail host were studied. Seven antigen components were shown to be shared between all three life stages of S. mansoni. Furthermore, one antigen was common to adult worm and snail, and one other antigen was shared between cercaria and snail. By using an intermediate gel containing lectin in the antigen-antibody system or by enzyme staining of the immune precipitates it was possible to identify schistosome antigens possessing lectin reactivity or enzyme activity. Characterization of enzyme activities revealed three individual precipitating antigens in adult worm of S. mansoni possessing esterase, leucyl-glycyl-glycine peptidase and phenylalanyl-leucine peptidase activities, respectively. One further precipitinogen with malate dehydrogenase activity was identified for all three life stages.

Interleukin-4 (IL-4) mRNA was detected in normal human peripheral blood mononuclear cells (PBMC) stimulated with concanavalin A by Northern blot analysis. The signal was undetectable in PBMC before the stimulation, but became detectable 3 hrs after the stimulation and reached a maximum in 3-6 h and disappeared gradually thereafter. Immunosuppressive drugs such as ciclosporin, hydrocortisone and prednisolone inhibited the IL-4 mRNA expression dose dependently. Interferon-gamma did not show any inhibitory effect on IL-4 gene expression.

In a test of adoptive cutaneous anaphylaxis, the influence of the phospholipase A2 inhibitor mepacrine, on the intensity of the local anaphylactic reaction was investigated in the skin of recipients following intracutaneous injection of syngenic immune splenocytes. Injection of the mepacrine solution with preincubated sensibilized splenocytes inhibits the cutaneous anaphylactic reaction after a single intravenous administration of allergen to recipients. The inoculation of immune splenocytes, preincubated in mepacrine but without the phospholipase A2 inhibitor, to the skin of syngeneic recipients is accompanied by less suppression of the local skin anaphylactic reaction than with a common injection of mepacrine with immune splenocytes.

The effect of platelet-activating factor (PAF) antagonist BN 52021 (0.06-2.5 mM) on the cytotoxic activity of mononuclear cells (MNC) from newly diagnosed type 1 diabetic patients against 51Cr-labeled Langerhans islets from neonatal rats was investigated in a 6-hour cytotoxicity test. A dose-dependent inhibition of anti-islet cytotoxicity by BN 52021 was observed. The suppression of the islet lysis was significant at a concentration of 0.6 mM BN 52021. During a 4-day cell culture, BN 52021 had no inhibitory effect on the antigen-mediated triggering of immunocytes with anti-islet cytotoxicity. The results suggest that the drug is only effective during immunocytolytic reactions of MNC against pancreatic islets. A PAF-independent action of BN 52021 can not be excluded at present.

Addition of the protein synthesis inhibitor cycloheximide (CX, 1 microgram/ml) and the RNA synthesis inhibitor actinomycin D (AD, 0.1 microgram/ml) to unfractionated mouse peritoneal mast cells simultaneously with IgE anti-DNP, for 24 h prior to challenge, completely blocked antigen-induced 5-HT release. Responses to anti-IgE were strongly abrogated whereas responses to the calcium ionophore A23187 were not affected. When CX and AD were added to presensitized cells their effects on antigen and anti-IgE-induced release were much reduced. These results suggest a requirement for protein synthesis during mast cell sensitization.

Peripheral-blood leucocytes from Dermatophagoides pteronyssinus- and/or Lolium perenne-allergic patients produce in vitro histamine-releasing factor (HRF) in an allergen-specific and concentration-dependent relationship. Maximum production of HRF occurred in cultures containing as little as 10-100 pg/ml crude allergen extract, although a second peak occurred at higher concentrations (10-100 micrograms/ml). While HRF was detectable in 1-hour cultures, maximal production required 24 h in culture. In contrast, HRF induced by streptokinase/streptodornase (SK/SD) was generally maximal after 1 h. Allergen-induced HRF production was almost exclusively associated with monocytes and B cells. In contrast, peripheral-blood T cells were the major source of induced HRF production in cultures containing SK/SD. Histamine-releasing cytokines are apparently produced by different cell populations, the activation of which may be dependent upon the characteristics of the stimulating antigen.