Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042961 (volvulus)
 4,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Onchocerca volvulus is a nematode that causes severe dermatitis and blindness in humans. Prior studies have shown that immune complexes in sera from onchocerciasis patients contain parasite antigens with M(r) of 23,000 and 65,000-70,000. Monoclonal antibody OV-1 binds to these antigens and to corresponding antigens in adult worm extracts and in vitro culture supernatants. OV-1 was used to immunoscreen an O. volvulus adult worm cDNA library. Clone OV1CF contains a 1632-bp open-reading frame that codes for a protein with a predicted M(r) of 63,000. The deduced protein sequence of OV1CF has 78% identity with Ascaris lumbricoides intermediate filament A and 40%-50% identity with several mammalian intermediate filaments. Antibodies raised to OV1CF bind to human keratin, and some sera from onchocerciasis patients contain antibodies to OV1CF and to keratin. Thus, immune complexes from onchocerciasis patients contain a parasite antigen that is immunologically cross-reactive with human intermediate filament proteins.
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PMID:Molecular characterization of a parasite antigen in sera from onchocerciasis patients that is immunologically cross-reactive with human keratin. 753 74

Improved methods for diagnosis of onchocerciasis are needed. We have recently identified immune complex-associated parasite antigens in sera from onchocerciasis patients. The goal of this study was to produce monoclonal antibodies to these antigens that might be used in antigen detection assays. Two monoclonal antibodies (OV-1 and OV-5) that bind to parasite antigens in immunoblots of PEG-precipitated immune complexes from human onchocerciasis sera and to corresponding antigens in adult worm extracts and excretory-secretory products were produced. The target epitopes of the monoclonals are heat stable, resistant to trypsin, and destroyed by Pronase. The two monoclonals produce similar but not identical patterns of binding to immunoblots of Onchocerca volvulus adult worm antigen with major bands at 43-47, 58-63, and 70 kDa. OV-1 and OV-5 appear to bind to two distinct but closely related epitopes, neither of which is phosphorylcholine. Immunoelectron microscopy showed that the epitopes recognized by these monoclonals are widely distributed in adult female worms, but concentrated in the uterus and intestine. Antigen assays based on these antibodies detected parasite antigen in 9 of 14 sera from onchocerciasis patients, but significant background signal was detected in some nonendemic human sera. Thus, although this study has provided new information on parasite antigens in sera from onchocerciasis patients, additional work will be needed to achieve the goal of producing a sensitive and specific antigen diagnostic test for onchocerciasis.
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PMID:Onchocerca volvulus: monoclonal antibodies to immune complex-associated parasite antigens. 769 Jul 12

Filarial parasites release macromolecules into their environment both in vitro and in vivo. These excretory-secretory products (E-S) have been studied with respect to function, vaccination potential, pathogenicity, and ability to serve as antigen targets for diagnostic tests. We have recently described monoclonal antibody OV-1 which binds to an intermediate filament in E-S and circulating antigens of Onchocerca volvulus. OV-1 also binds to cross-reactive antigens of Brugia malayi. Therefore, OV-1 was used to immunoscreen a B. malayi adult worm cDNA library in an attempt to clone a homologue (BMIF). BMIF is a 1664-bp full-length transcript which codes for 505 amino acids. BMIF has 95% sequence homology at the amino-acid level to OV1CF, an O. volvulus intermediate filament that was also selected with OV-1, and 75% homology to Ascaris intermediate filament A. Southern blot analysis suggests that BMIF is confined to a single location in the genomic DNA of B. malayi. Antibodies raised to BMIF identified native antigens in immunoblots of B. malayi adult worms, infective larvae and adult E-S. In addition, the antibody also bound to a 60-kDa antigen in immunoblots of poly(ethylene glycol)-precipitated immune complexes in sera from B. malayi infected patients. Localization studies showed that the antigen encoded by BMIF is present in the hypodermis, developing embryos and muscle of adult B. malayi. These studies show that BMIF is an E-S product of B. malayi adult worms which is detectable in sera from patients with brugian filariasis.
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PMID:Molecular characterization of a Brugia malayi intermediate filament protein which is an excretory-secretory product of adult worms. 857 31