title: Rabbit F(ab')2 antihuman IgE is a universal skin test reagent in the evaluation of skin mast cell degranulation in vivo.
abstract: Antihuman IgE is often used to study basophil- and mast cell-mediator release in vitro but is infrequently used in vivo. To evaluate in vivo skin reactivity to anti-IgE, an affinity-purified rabbit F(ab')2 fragment of antihuman IgE was injected intradermally in 22 nonallergic and 27 allergic subjects. All 49 subjects (including a subject with less than 1 ng/ml of total serum IgE) had positive immediate cutaneous reactions to anti-IgE. Although total serum IgE level was weakly correlated (r = -0.51; p less than 0.005) with in vivo skin reactivity to anti-IgE for the entire population, allergic subjects did not have significantly increased skin reactivity compared to nonallergic subjects (p = 0.18), despite having higher total serum IgE levels (p less than 0.002). A late-phase cutaneous response (LPR) to anti-IgE occurred in 60% of the allergic and in 50% of the nonallergic subjects. Subjects with an LPR required approximately tenfold higher concentrations of anti-IgE to produce an immediate wheal of 10 mm compared to subjects who did not develop an LPR (p = 0.02), suggesting that the concentration of the stimulus injected is more important for the development of a LPR than the size of the immediate cutaneous response. Skin reactivity to codeine phosphate (a non-IgE-dependent secretagogue) was correlated with skin reactivity to anti-IgE (r = 0.47; p less than 0.05), suggesting that in vivo skin mast cell degranulation is partially a function of mast cell releasability.(ABSTRACT TRUNCATED AT 250 WORDS)
authors: Johns Hopkins University School of Medicine, Division of Clinical Immunology, Good Samaritan Hospital, Baltimore, Md 21239.
authors: M E
authors: ME
authors: Weiss
authors: P
authors: P
authors: Trent
authors: R
authors: R
authors: Fisher
authors: P S
authors: PS
authors: Norman
authors: W E
authors: WE
authors: Waterbury
authors: N F
authors: NF
authors: Adkinson
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000888:Antibodies, Anti-Idiotypic; D002846:Chromatography, Affinity; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D006636:Histamine Release; D006801:Humans; D006967:Hypersensitivity / Q000175:diagnosis*; D007111:Immunity, Cellular; D007073:Immunoglobulin E / Q000276:immunology*; D007140:Immunoglobulin Fab Fragments; D008297:Male; D008407:Mast Cells / Q000276:immunology*; D008875:Middle Aged; D011817:Rabbits; D012882:Skin Tests
chemical_list: D000888:Antibodies, Anti-Idiotypic; D007140:Immunoglobulin Fab Fragments; C026408:anti-IgE antibodies; D007073:Immunoglobulin E