TY  - JOUR
AB  - BACKGROUND: Flow cytometry-based basophil activation tests (BAT) have been performed with various modifications, differing in the use of distinct identification and activation markers. Established tests use liquid reagents while a new development involves the use of tubes with dried antibody reagents. The aim of this pilot study was to compare these two techniques in patients with insect venom allergy. METHODS: Seventeen patients with an insect venom allergy were included in the study. The established "BAT 1" utilizes conventional antibody solutions of anti-CCR3 for basophil identification and anti-CD63 to assess basophil activation, whereas "BAT 2" uses dried anti-CD45, anti-CD3, anti-CRTH2, anti-203c and anti-CD63 for identification and activation measurement of basophils. Negative and positive controls as well as incubations with honey bee venom and yellow jacket venom at three concentrations were performed. RESULTS: Seven patients had to be excluded due to low basophil counts, high values in negative controls or negative positive controls. For the remaining 10 patients the overall mean (± SD) difference in activated basophils between the two tests was 0.2 (± 12.2) %P. In a Bland-Altman plot, the limit of agreement (LoA) ranged from 24.0 to -23.7. In the qualitative evaluation (value below/above cut-off) Cohen's kappa was 0.77 indicating substantial agreement. BAT 2 took longer to perform than BAT 1 and was more expensive. CONCLUSION: The BAT 2 technique represents an interesting innovation, however, it was found to be less suitable compared to an established BAT for the routine diagnosis of insect venom allergies.
AU  - Waldherr, S.*
AU  - Hils, M.*
AU  - Köberle, M.*
AU  - Brockow, K.*
AU  - Darsow, U.*
AU  - Blank, S.
AU  - Biedermann, T.*
AU  - Eberlein, B.*
C1  - 70547
C2  - 55666
CY  - Campus, 4 Crinan St, London N1 9xw, England
TI  - Basophil activation in insect venom allergy: Comparison of an established test using liquid reagents with a test using 5-color tubes with dried antibody reagents.
JO  - BMC Immunol.
VL  - 25
IS  - 1
PB  - Bmc
PY  - 2024
ER  - 

TY  - JOUR
AB  - Background: While dendritic cells (DCs) can induce tolerance in T cells, little is known about tolerance induction in DCs themselves. We have analysed tolerance induced in human in-vitro generated DCs by repeated stimulation with ligands for TLR4 and TLR2. Results: DCs stimulated with the TLR4 ligand LPS did show a rapid and pronounced expression of TNF mRNA and protein. When DCs were pre-cultured for 2 days with 5 ng LPS/ml then the subsequent response to stimulation with a high dose of LPS (500 ng/ml) was strongly reduced for bot TNF mRNA and protein. At the promoter level there was a reduced transactivation by the -1173 bp TNF promoter and by a construct with a tetrameric NF-kappaB motif. Within the signalling cascade leading to NF-kappaB activation we found an ablation of the IRAK-1 adaptor protein in LPS-tolerant DCs. Pre-culture of DCs with the TLR2 ligand Pam3Cys also led to tolerance with respect to TNF gene expression and IRAK-1 protein was ablated in such tolerant cells as well, while IRAK-4 protein levels were unchanged. Conclusion: These data show that TLR-ligands can render DCs tolerant with respect to TNF gene expression by a mechanism that likely involves blockade of signal transduction at the level of IRAK-1.
AU  - Albrecht, V.
AU  - Hofer, T.P.
AU  - Foxwell, B.*
AU  - Frankenberger, M.
AU  - Ziegler-Heitbrock, L.
C1  - 5845
C2  - 26030
TI  - Tolerance induced via TLR2 and TLR4 in human dendritic cells: Role of IRAK-1.
JO  - BMC Immunol.
VL  - 9
PB  - BioMed Central
PY  - 2008
ER  -