Specific IgE to colophony?
BACKGROUND
Colophony (rosin) is a natural product obtained from coniferous trees. It is used in a diverse range of products such as adhesives, ink, paints and soldering fluxes. Some workers exposed to colophony during soldering can develop occupational asthma; at present, no specific IgE test is available to assess sensitization to colophony.


METHODS
Serum samples were obtained from exposed symptomatic individuals (n = 7), some with a likely diagnosis of occupational asthma, exposed asymptomatic individuals (n = 10) and unexposed individuals (n = 11). Serum was tested for specific IgE antibodies against a protein extract produced following in vitro challenge of mono-mac-6 cells with colophony extract.


RESULTS
Serum from exposed symptomatic individuals showed increased binding of specific IgE antibodies to a range of colophony-cell protein conjugates [29% (2/7) of samples tested when cut-off > 0.1 or 86% (6/7) of samples tested when cut-off > 0%] compared with both the exposed asymptomatic [0% when cut-off > 0.1, or 20% when cut-off > 0% (2/10)] and the non-exposed control populations [0% when cut-off > 0.1, or 27% when cut-off > 0% (3/11)].


CONCLUSIONS
This novel approach for the production of conjugates to assess sensitization to colophony was able to detect specific IgE in colophony-exposed workers with a likely diagnosis of occupational asthma.
Elms
Joanne
J
Health & Safety Executive, Hagley Road, Birmingham B16 8HS, UK.
Fishwick
David
D
Robinson
Edward
E
Burge
Sherwood
S
Huggins
Vicky
V
Barber
Chris
C
Williams
Nerys
N
Curran
Andrew
A
D000328:Adult; D001249:Asthma / Q000276:immunology*; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D008875:Middle Aged; D009784:Occupational Diseases / Q000276:immunology*; D011852:Radioallergosorbent Test / Q000379:methods; D012116:Resins, Plant / Q000009:adverse effects*
D012116:Resins, Plant; D007073:Immunoglobulin E; C013893:rosin