Reactivity to IgE-dependent histamine-releasing factor is due to monomeric IgE.
BACKGROUND
IgE-dependent histamine-releasing factor (HRF) can distinguish between IgE+ and IgE-. In contrast to IgE-, IgE+ sensitizes basophils to release histamine in response to HRF. But we do not know what particular feature distinguishes IgE+ from IgE-. The objective was to investigate the hypothesis that IgE+ is polymeric IgE.


METHODS
IgE+ plasma was separated by size-exclusion chromatography. The basophil-sensitizing capacity of the fractions was analyzed in response to HRF produced by mononuclear cells.


RESULTS
We showed that monomeric IgE sensitized basophils to release histamine in response to HRF and to house-dust mite, whereas no enhanced reactivity was found in the fractions containing polymeric IgE.


CONCLUSIONS
HRF reacts with monomeric IgE, and not (exclusively) with polymeric IgE.
Department of Allergy, Academic Medical Centre, University of Amsterdam, The Netherlands.
I K
IK
Budde
M
M
Aalbers
R C
RC
Aalberse
J S
JS
van der Zee
E F
EF
Knol
D039741:Antigens, Dermatophagoides; D001491:Basophils / Q000276:immunology / Q000378:metabolism; D014408:Biomarkers, Tumor; D001704:Biopolymers; D005591:Chemical Fractionation; D006023:Glycoproteins / Q000276:immunology; D006636:Histamine Release; D006801:Humans; D007073:Immunoglobulin E / Q000378:metabolism*; D008222:Lymphokines / Q000494:pharmacology*; D000090324:Tumor Protein, Translationally-Controlled 1
D039741:Antigens, Dermatophagoides; D014408:Biomarkers, Tumor; D001704:Biopolymers; D006023:Glycoproteins; D008222:Lymphokines; D000090324:Tumor Protein, Translationally-Controlled 1; D007073:Immunoglobulin E