We have identified a major allergenic protein from rye-grass pollen, tentatively desinated Lolplb of 31 kDa and with pI 9.0. A cDNA clone encoding Lol plb has been isolated, sequenced, and characterized. Lol pIb is located mainly in the starch granules. This is a distinct allergen from LolpI, which is located in the cytosol. Lolplb is synthesized in pollen as a pre-allergen with a transit peptide targeting the allergen to amyloplasts.

We have isolated a full length cDNA clone encoding the major glycoprotein allergen Lol pI. The clone was selected using a combination of immunological screening of a cDNA expression library and PCR amplification of Lol pI‐specific transcripts. Lol pI expressed in bacteria as a fusion protein shows recognition by specific IgE antibodies present in sera of grass pollen‐allergic subjects. Northern analysis has shown that the Lol pI transcripts are expressed only in pollen of rye‐grass. Molecular cloning of Lol pI provides a molecular genetic approach to study the structure—function relationship of allergens.

No abstract

Two isoallergens of Cyn d I were isolated using preparative isoelectric focussing, and were designated Cyn d Ia and b. These isoallergens differ in their pI, molecular weight (Cyn d Ia, 32 kD and Cyn d Ib, 31 kD) and their NH₂-terminal sequence. Four monoclonal antibodies (Mabs) were produced using Cyn d la as antigen. These Mabs recognized both Cyn d Ia and b. One of the Mabs recognized four different pI forms of Cyn d I on 2D gels. The Mabs also recognized cross-reactive epitopes on proteins from eight other grasses including rye grass, timothy grass, Kentucky bluegrass and Johnson grass.

No abstract