Partial Characterization of bermuda, carabao, cogon, and talahib grass pollen extracts

@#<p style="text-align: justify;"><strong>BACKGROUND</strong>: Grass pollen grains are important causes of respiratory allergies. The Philippines has a different grass flora compared to that of western countries, so pollen extracts have to be processed for use in the diagnosis and treatment of respiratory allergies. The local pollen extracts available in clinical practice have not yet been characterized, which is important in improving extract quality.<br /><strong>OBJECTIVE:</strong> This study aims to perform physicochemical characterization through protein content determination and gradient sodium-dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of extracts from four grasses: Cynodon dactylon (bermuda grass), Axonopus compressus (carabao grass), Imperata cylindrica (cogon), and Saccharum spontaneum (talahib) and immunologic characterization by identifying its IgE-binding component through immunoblot.<br /><strong>METHODS</strong>: This is a descriptive study. The pollen grains were processed into allergen extracts and protein contents were determined. The extracts were separated by gradient SDS-PAGE and subjected to immunoblotting. Bands were visualized using Fluorchem C2 aided with Alpha View Software.<br /><strong>RESULTS:</strong> Total protein in the pollen extracts ranged from 281.3-968.61 µg/ml. Protein bands of bermuda were in the 14.4-66.3 kDa range, carabao grass at 3.5-66.3 kDa, cogon at 3.5-200 kDA, and talahib at 21.5-66.3 kDa. A single IgE-binding protein band was seen on immunoblot at 55.4 kDa using a single serum sample.<br /><strong>CONCLUSION</strong>: Protein contents of the allergen extracts vary. The molecular weights of the different protein bands seem to correspond to known groups of grass pollen allergens. There was only one IgE-binding protein band seen on preliminary immunoblot.</p>

Immunoglobulin E-binding reactivities of natural pollen grain extracts from selected grass species in the Philippines

BACKGROUND: Pollen grains have been reported to be present in the Philippine atmosphere but studies regarding their allergenicity are limited. OBJECTIVE: The present study aimed to profile the sensitization of allergic individuals to selected grass pollen species and to characterize the pollen proteins that may be responsible for this allergenic response. METHODS: The protein profile of the grass pollen extracts from Cynodon dactylon, Saccharum spontaneum, Sporobulus indicus, Chloris barbata, Oryza sativa, Imperata cylindrica, and Zea mays was analyzed by Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis. The specific-IgE profile of the allergic individuals and the allergenic potential of the pollen extracts were evaluated through Enzyme-linked Immunosorbent Assay and IgE immunoblotting. RESULTS: Sensitization of the allergic individuals to the pollen extracts was detected with I. cylindrica and O. sativa to be the most frequently recognized with more that 92% reactivity, whereas for C. dactylon and Z. mays, were found to have less than 25% reactivity. CONCLUSION: Multiple IgE-binding proteins from S. indicus, S. spontaneum and C. barbata that were detected may be responsible for the allergic reactions among Filipino subjects.