ABSTRACT
Ligustrum vulgare (Privet) pollen proteins are responsible for allergies in susceptible individuals in many regions of the world. This study investigated the immunochemical characterization of Privet pollen extract and the occurrence of skin prick test reactivity to Privet and other allergenic pollen grains in allergic rhinitis patients. All subjects experienced a skin prick test with twenty-two allergen extracts. sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) separated Privet pollen extract, IgE-immunoblotting, and specific ELISA procedures determined the allergenic profile on forty-five Privet allergic patients. A positive allergic reaction to L. vulgare pollen extract was observed in forty-five (31.4%) out of 145 patients. Ten resolved protein fractions were found on SDS-PAGE, ranging from 10 to 80 kDa. IgE-specific antibodies interacted with several allergenic protein bands from Privet-allergic patients in the immunoblotting assay. The most significant interaction was observed in proteins with molecular weights of approximately 15, 18, 43, and 66 kDa. Privet pollen is regarded as a potent allergen composed of IgE-binding constituents. Considering the high allergenicity of Privet pollen grains and since many countries are rich in this plant, identification and production of recombinant forms of common allergens in this species can be used for developing more efficient diagnostic, therapeutic, and preventive approaches.
Subject(s)
Hypersensitivity , Ligustrum , Allergens , Electrophoresis, Polyacrylamide Gel , Humans , Hypersensitivity/diagnosis , Immunoglobulin E , Iran , Plant Extracts , Plant Proteins , Pollen , Skin TestsABSTRACT
BACKGROUND: Pollen is one of the most common allergens that cause respiratory allergies worldwide. Pollen grains from poplars have been reported as important sources of pollinosis in many countries. OBJECTIVE: The aim of the present study was to determine the molecular and immunochemical characterization of Pop n 2, a novel allergen of Populus nigra (P nigra) pollen extract. METHODS: In this study, the pollen extract of P nigra was analysed by SDS-PAGE, and the allergenic profile was determined by IgE immunoblotting and specific ELISA using the sera of twenty allergic patients. The coding sequence of Pop n 2 was cloned and expressed in the Escherichia coli BL21 (DE3) using plasmid the pET-21b (+). Finally, the expressed recombinant Pop n 2 was purified by affinity chromatography. RESULTS: Pop n 2 belongs to the profilin family with a molecular weight of approximately 14 kDa. Pop n 2 is the most IgE-reactive protein (about 65%) in the P nigra pollen extract. The cDNA sequencing results indicated an open reading frame 396 bp that encodes 131 amino acid residues. The results of ELISA and Immunoblotting assays showed that recombinant Pop n 2 could react with the IgE antibody in patients' sera, like its natural counterpart. CONCLUSION: Our data revealed that Pop n 2 is a significant allergen in the P nigra pollen extract. Moreover, we observed that the recombinant Pop n 2 produced by the pET-21b (+) vector in the E colisystem acts as its natural counterpart.
Subject(s)
Populus , Allergens , Amino Acid Sequence , Cloning, Molecular , Cross Reactions , Humans , Immunoglobulin E , Plant Proteins/genetics , Pollen , Populus/genetics , Populus/metabolism , Recombinant ProteinsABSTRACT
The association of HLA class II genes with ulcerative colitis (UC) as an autoimmune disease has been investigated for several years. However, factors responsible for genetic predisposition of this disease have so far not been clearly understood. In this study, for the first time, we aimed to investigate the association between HLA-DRB1 types and UC in the population of Kerman, a city southeast Iran. HLA typing was performed among 85 UC patients and 95 healthy controls using PCR amplification, employing sequence specific primers (PCR-SSP). The DRB1 frequencies were determined in the patients and controls. HLA-DRB1*04 was negatively associated with UC. Furthermore, HLA-DRB1*13 was significantly associated with severity of the disease (p=0.01) among UC patients. This is the novel result that describes an association of HLA-DRB1*13 with UC and also shows the protective role of HLA-DRB1*04 against the disease in people of Kerman.
