Elevated Bfl-1 expression upon allergen provocation in birch-pollen allergic patients (A) and in lesions of atopic dermatitis (AD) and psoriasis patients (PSO) (B).

<p>An enzymatical staining for tryptase followed by an immunohistochemical staining of Bfl-1 was performed. The results are presented as the percentage of mast cells expressing Bfl-1.</p

IgECL-induced survival of human mast cells.

<p>(A). CBMC upon IgECL. (B) LAD-2 cells upon IgECL. Cells were sensitized with 1 μg/mL of IgE overnight before cytokine-deprived and challenged with anti-IgE. After 24 hrs the cell viability was enumerated using trypan blue exclusion. N=3–4.</p

Bfl-1 is expressed in skin tissue mast cells.

<p>An enzymatical staining for tryptase followed by an immunohistochemical staining of Bfl-1 (upper panel) and was performed on atopic dermatitis (AD) lesional skin. Isotype control staining following tryptase staining (lower panel).</p

siRNA targeting <i>BFL-1</i> but not <i>MCL-1</i> diminishes activation-induced survival of human mast cells.

<p>(A) The upregulation of <i>BFL-1</i> and <i>MCL-1</i> following IgECL in CBMCs is abolished following targeted siRNA treatment as verified 30 hours post-transfection by quantative PCR. Cells were transfected with 100 nM siRNA, sensitized with 1 μg/mL of IgE and challenged with 2 μg/mL anti-IgE before expression was determined. Data correspond to one representative experiment using one donor. Similar result was obtained for another donor. (B) <i>BFL-1</i> but not <i>MCL-1</i> siRNA treated CBMCs show decreased survival upon IgECL compared to control siRNA treated cells. Cells were transfected, sensitized with 1 μg/mL of IgE and 24 hours post-transfection cytokine-deprived and challenged with 2 μg/mL anti-IgE before being enumerated 24 hours later using the vital dye trypan blue. N=6. (C) The upregulation of <i>BFL-1</i> and <i>MCL-1</i> following IgECL in LAD-2 cells is abolished following targeted siRNA treatment as described above. (D) <i>BFL-1</i> but not <i>MCL-1</i> siRNA treated LAD-2 cells show decreased survival upon IgECL compared to control siRNA treated cells. N=4. Change in viability is percentage viable cytokine-deprived cells deducted from viable cytokine-deprived cells following IgECL. (E) Bfl-1 is down-regulated in LAD-2 cells following siRNA treatment targeting <i>BFL-1</i> as compared to control siRNA in immunohistochemical stainings for Bfl-1 expression.</p

Activation-induced mast cell survival following IgECL in presence of ABT-737 and roscovitine.

<p>(A) CBMC treated with 0.5 μM ABT-737 alone or in combination with 5 μM roscovitine following IgECL. N=6–3. (B) LAD-2 treated with 0.5 μM ABT-737 alone or in combination with 5 μM roscovitine following IgECL. N=3 Viability was assessed after 24 hrs using propidium iodide plus FITC-conjugated Annexin V. Change in viability is expressed as percentage viable cells after treatment deducted from untreated cells. ABT-737 = ABT, roscovitine = rosc.</p