Immunobiochemical Characterization of <i>Putranjiva roxburghii</i> Pollen Extract and Cross-Reactivity with <i>Ricinus communis</i>

Abstract

Putranjiva roxburghii (PR) pollen has been found to be an important aeroallergen for type I hypersensitivity. In the present study, the IgE binding proteins of PR pollen have been characterized and compared with pollen allergens of Ricinus communis (RC) belonging to family Euphorbiaceae. On isoelectric focusing, PR pollen extract resolved into 35 bands (pI 3–9), whereas SDS-PAGE separated it into 18 protein components (MW 14–100 kD). Pooled patient’s sera (ID +ve to PR) recognized 12 allergenic proteins in Putranjiva and five of them (MWs 92, 80, 55,43 and 30 kD) showed immunologic reactivity to most of the sera samples tested individually by immunoblot. A number of shared allergenic proteins (MWs 92, 80, 66, 50, 43 and 14 kD) were observed between PR and RC pollen extracts on immunoblot using Putranjiva allergic serum pool. Inhibition in the binding for most of PR pollen allergenic proteins was obtained with higher concentration of RC extract than PR itself, depicting the presence of cross-reacting allergens in both. Putranjiva pollen extract was fractionated by a combination of DEAE Sephadex-A 50 and Sephadex-G 200 column chromatography. Periodate deglycosylation of western blotted PR extract and Put I fraction indicated the involvement of carbohydrate moieties in the allergenic activity. Of the two fractions from Put I (la and lb), Put lb was found to be the most allergenic protein by ELISA inhibition. Dot blot analysis with individual patients sera identified it as a major allergen of PR.

Analysis of IgE binding proteins of mesquite (Prosopis juliflora) pollen and cross-reactivity with predominant tree pollens

“…Salvadora and Prosopis species are also distributed to arid (desert) regions in other continents. The tree species selected for this study are well known sources of allergens (Malik et al, 1991;Singh et al, 1997;Singh and Kumar, 2003). IgE inhibition assays demonstrated cross-reactive proteins of 14, 16, 35, 41, 52 and 66 kDa in P. juliflora and these tree species.…”

“…Previous studies have defined the allergenic properties of certain tree species namely Holoptelea integrifolia, Betula verrucosa, Putranjiva roxburghii, Olea europea and Fraxinus excelsior (Malik et al, 1991;Hirschwehr et al, 1993;Singh et al, 1997;Sanchez et al, 2002;Niederberger et al, 2002). Like grasses, tree pollens also contain some shared and specific allergens (Gonzalez et al, 2000;Niederberger et al, 2002).…”

Purification and Partial Characterization ofa 67-kD Cross-React ive Allergen from <i>Imperata cylindrica</i> Pollen Extract

“…Nonspecific inhibition was checked by inhibiting the sera with non-grass pollen extract, Artemisia scoparia. Other steps were carried out as described earlier [7]. …”

Culture filtrate antigens and allergens of Epicoccum nigrum cultivated in modified semi-synthetic medium

“…The CF/spore-mycelial antigen of EN, after SDS-PAGE, was transferred to a nitrocellulose membrane and treated with 0.02 mol/l sodium metaperiodate, overnight in dark at 4°C as described earlier [17]. After oxidation, the nonspecific sites of the membrane were blocked and used for IgE immunoblot using pooled sera from EN-positive patients.…”