The development and use of a polyclonal sandwich enz:fme immuno assay in occupational exposure assessment of Natural Rubber Latex proteins

Abstract

Latex allergy among health care workers remains a serious occupational health problem with a recently reported prevalence oÊ latex allergy between 5o/o and l5o/o. The main determinancs of air and dermal larex allergen exposure have been identified, but clear exposure-response relations have noc yer been developed, partly because ofa lack ofa valid assay. Because oF posicive previous e[forts, a polyclonal sandwich EIA For the measurement of larex allergens in sample exrracts was developed. A¡ti-latex IgG, derecting a wide range of latex proteins, was obtained using serum From a rabbit. Our assay was validated through several laboratory experiments, including sensitiviry and specificiry cescing, measuring reactivicy of extracts from gloves and air samples, and a comparison analysis with an existing IgE inhibition assay. The results show the assay to be specific and ro have a sensiúviey of 2.5-3.0 ngiml, or 6 nglm3 for full shift inhalation exposure meesurements. The assay is successful in measuring latex proteins in extracß from powdered gloves, filters From airborne sampling and skin pads. Furrhermore, the comparacive analysis with the existing IgE inhibition assay shows a high correlation For rhe airborne dust samples (r'z=0.7-0.8) and glove extracts (rt=0.9). I¡ is concluded chat a polyclonal immuno assay might be a valuable cool in latex exposure assessmenr as it describes rhe overall allergeniciry of latex products, normally conraining a range ofdifferent larex proteins. Furrher validation oFthe assay is necessary and practical value should be rested.