Recombinant major urinary proteins of the mouse in specific IgE and IgG testing.
BACKGROUND
Recombinant allergens are preferred over natural allergen extracts in measuring antibodies. We tested the use of recombinant variants of the major mouse allergen Mus m 1 in detection of mouse-specific antibodies in sera of laboratory animal workers and children.


METHODS
Six recombinant major urinary proteins (MUPs) were produced and antibody-binding capacity was compared to natural Mus m 1 and to mouse urine extract. In a specific subset, cross-reactivity of MUP with Mus m 1 and between the different recombinant MUPs was determined.


RESULTS
For IgE antibodies, MUP8 showed high cross-reactivity with Mus m 1. MUP8-specific IgE was found in 55% of the mouse urine IgE-positive sera. Specific IgG and IgG4 antibodies against natural Mus m 1 correlated strongly with antibodies against recombinant MUP8 and were cross-reactive. IgG4 levels against MUP8 and mouse urine extract correlated, but detection of mouse urine-specific IgG4 in the absence of MUP-specific IgG4 was not uncommon. Cross-reactivity of IgG antibodies between MUP8 and Mus m 1 as well as between the different MUPs was high and inhibition varied between 54 and 99%.


CONCLUSIONS
The mouse allergen Mus m 1 can be replaced in antibody testing by recombinant MUP8. Other MUPs, except MUP4, are interchangeable with MUP8. However, mouse urine extract showed better detection of both mouse-specific IgE and IgG4 levels. Other components in the mouse urine, like mouse albumin and other yet unidentified components, also induce IgE and IgG4 antibodies.
Krop
Esmeralda J M
EJ
Department of Pulmonology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. e.j.m.krop@iras.uu.nl
Matsui
Elizabeth C
EC
Sharrow
Scott D
SD
Stone
Martin J
MJ
Gerber
Peter
P
van der Zee
Jaring S
JS
Chapman
Martin D
MD
Aalberse
Rob C
RC
D000485:Allergens / Q000276:immunology*; D000818:Animals; D002675:Child, Preschool; D003429:Cross Reactions; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology*; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008297:Male; D051379:Mice; D011506:Proteins / Q000235:genetics / Q000276:immunology*; D011852:Radioallergosorbent Test; D011863:Radioimmunoassay; D011994:Recombinant Proteins / Q000276:immunology*
D000485:Allergens; D007074:Immunoglobulin G; C518791:Mus m 1 allergen, Mus musculus; D011506:Proteins; D011994:Recombinant Proteins; C035737:major urinary proteins; D007073:Immunoglobulin E