IMMUNODETECTION OF LATEX ANTIGENS

Background: Protein antigens in latex products can cause type I reactions. In the past antigens have been measured by protein assays, high-performance liquid chromatography, RAST inhibition, and skin tests. We examined the use of a mouse monoclonal antibody (CRI-C) to later in the detection of latex antigens. Methods: CRI-C was raised by standard techniques after immunization of a BALB/c mouse with ammoniated latex. Medical gloves were extracted and assayed with: (1) standard protein assays, (2) RAST inhibition assays with sera from health care workers allergic to latex and patients with spina bifida, (3) an ELISA with a biotinylated form of CRI-C (BIC). Reference proteins included bovine serum albumin for the protein assays and nonammoniated latex and affinity-purified C antigen for the immunoassays. Results: Among the protein assays, the best correlation was between the Bradford and bicinchoninic acid assays. In absolute numbers the Bradford assay produced the lowest results, and OD280 the highest. The OD280 BCA, and Bradford methods ''detected'' protein in vinyl gloves. The results of RAST inhibition and BiC ELISA correlated with the protein assays. These immunoassays appeared to be more specific than the protein assays. Conclusions: The BiC ELISA is an easy and reproducible in vitro assay of relevant latex antigen. Clinical correlation will be required for validation.