The annual plant Taraxacum kok-saghyz, commonly called Russian dandelion, has recently gained commercial attention as an alternative source to the rubber tree, Hevea brasiliensis, for natural rubber latex. While producing rubber of equivalent quality, the potential application of TKS latex for hypoallergenic products remains to be determined. In order to quantify the allergenicity of TKS latex proteins, we compared the extent of anti-Hevea latex polyclonal and monoclonal antibody cross-reactivity toward Hevea latex proteins to that of TKS latex proteins by quantitative ELISA methods and semi-quantitative image densitometry. ELISA measurement of polyclonal antibody recognition toward TKS latex proteins was on the order of one-tenth relative to equal amounts of Hevea latex protein, while recognition by the monoclonal antibody was below 2%. Immunoblots confirmed significantly reduced polyclonal antibody recognition toward TKS latex proteins, in the same range as the cross-reactivity exhibited toward the rubber-producing plant, Lactuca sativa and Glycine max, a non-rubber-producing plant. Despite the presence of cross-reactivity, these quantitative results support TKS as an alternative source of latex that may require lessintensive processing for the reduction of antigenic proteins in the manufacture of hypoallergenic natural rubber latex products.