IL-1 receptor-type expression in relation to atopy.
BACKGROUND
IL-1 has 2 receptors, type I (IL-1RI) and type II (IL-1RII), which have 2 forms each, membrane (m) and soluble (s). When IL-1 binds to mIL-1RI, the active receptor, an inflammatory response is initiated, which does not occur when IL-1 binds to mIL-1RII, the decoy receptor. Both sIL-1RI and sIL-1RII function as IL-1-mopping mechanisms. We hypothesized that the ratio of active (mIL-1RI) to inactive (mIL-1RII, sIL-1RI, and sIL-1RII) receptors is important in determining the amount of inflammation produced in allergic reactions.


OBJECTIVE
Our aim was to compare the concentrations of mIL-1RI and mIL-1RII on cultured PBLs and sIL-1RI, sIL-1RII, and IL-1beta in sera and supernatants of cultured PBMCs from atopic and nonatopic subjects.


METHODS
The membrane receptors, soluble receptors, and IL-1beta concentrations were measured by ELISA with specific mAbs.


RESULTS
Although there was no difference in the level of serum IL-1beta between the 2 groups, PBMCs from atopic persons spontaneously secreted higher levels of IL-1beta than those from nonatopic donors (P < .05). PBLs from atopic subjects compared with those from nonatopic individuals expressed higher mIL-1RI (P < .0001) and mIL-1RII (P < .05). Levels of both the soluble receptors from both serum (P < .0001) and PBMCs (P < .05) of nonatopic donors were higher than those found in atopic donors.


CONCLUSIONS
This augmentation of mIL-1RI concomitant with a reduction in soluble receptors may be an important contributory factor to the inflammation that occurs with allergen exposure.
Gupta
K
K
Creighton University, Department of Medicine/Division of Allergy, Omaha, Nebraska, USA.
Bewtra
A
A
D000328:Adult; D005260:Female; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood* / Q000378:metabolism; D007375:Interleukin-1 / Q000097:blood; D008297:Male; D008565:Membrane Proteins / Q000097:blood; D017472:Receptors, Interleukin-1 / Q000096:biosynthesis / Q000097:blood*; D012995:Solubility
D007375:Interleukin-1; D008565:Membrane Proteins; D017472:Receptors, Interleukin-1