Expressed in pollen (at protein level). Causes an allergic reaction in human. Binds to IgE in patients allergic to the pollen of cedar tree (PubMed:10657673, PubMed:10969020, PubMed:18270658). Native protein binds to IgE in 43% of the 14 patients and in 33% of the 36 patients tested allergic to the pollen of mountain cedar or Japanese cedar, respectively (PubMed:10657673). Recombinant protein binds to IgE of patients allergic to mountain cedar pollen (PubMed:18270658). Extracting this recombinant allergen by vacuum infiltration from the plant (Nicotiana benthamiana) apoplast via tobacco mosaic virus vector could be useful in diagnostic and/or immunotherapeutic strategies for cedar allergy as it is a more convenient and inexpensive method than expression in the yeast (Pichia pastoris) secretion system. Belongs to the thaumatin family.