English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

These studies were conducted to investigate the potential use of a flow cytometric analysis method for the identification and differentiation of chemicals with the capacity to induce irritation, IgE- or T cell-mediated hypersensitivity responses. An initial study investigated the ability of equally sensitizing concentrations (determined by local lymph node assay) of IgE-mediated (Toluene Diisocyanate-TDI) and T cell-mediated (Dinitrofluorobenzene-DNFB) allergens to differentially modulate the IgE+B220+ population in the lymph nodes draining the dermal exposure site. Sodium lauryl sulfate (SLS) was also tested as a nonsensitizing irritant control. Female B6C3F1 mice were dermally exposed once daily for 4 consecutive days, with the optimum time point for analysis determined by examining the IgE+B220+ population 8, 10, and 12 days post-initial chemical exposure. At the peak time point, day 10, the IgE+B220+ population was significantly elevated in TDI (41%), while moderately elevated in DNFB (18%) exposed animals when compared to the vehicle (0.8%), and remained unchanged in SLS (2.2%) exposed animals when compared to the ethanol control (2.5%). Experiments in our laboratory and others have demonstrated that the draining lymph node B220+ population becomes significantly elevated following exposure to allergens (IgE- and T cell-mediated), not irritants, allowing for their differentiation. An existing mouse ear swelling assay was used to identify chemical irritants. Therefore, using the endpoints of percent ear swelling, percent B220+ cells, and percent IgE+B220+ cells, a combined irritancy/phenotypic analysis assay was developed and tested with tetradecane (irritant), toluene diisocyanate, trimellitic anhydride (IgE-mediated allergens), benzalkonium chloride, dinitrofluorobenzene, oxazolone, and dinitrochlorobenzene (T cell-mediated allergens) over a range of concentrations. Based upon the pattern of response observed, a paradigm was developed for continued evaluation: Irritant exposure will result in significant ear swelling without altering the B220+ or IgE+B220+ populations. Exposure to sensitizers (IgE-mediated or T cell-mediated) will increase the B220+ population and the percent ear swelling will remain unchanged or will significantly increase, depending on the irritancy capacity of the chemical. Both the IgE+B220+ and B220+ populations will become elevated at the same test concentration following exposure to IgE-mediated, hypersensitivity inducing allergens. At its peak, the percent of IgE+B220+ cells will be equal to the percent of B220+ cells. The B220+ population will increase at a lower test concentration than the IgE+B220+ population, following exposure to T cell-mediated, hypersensitivity inducing allergens. At its peak, the percent of IgE+B220+ cells will reach less than half that of the percent of B220+ cells. The irritancy/phenotypic analysis method may represent a single murine assay able to identify and differentiate chemicals with the capacity to induce irritation, or IgE-mediated or T cell-mediated responses.

toxicological sciences

Development of a flow cytometry assay for the identification and differentiation of chemicals with the potential to elicit irritation, IgE-mediated, or T cell-mediated hypersensitivity responses