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Akitoyo Hotta

Publications and source records attributed to Akitoyo Hotta.

7 recordsLinked to original sources
PubMed2006

Preparation of monoclonal antibodies for detection and identification of Francisella tularensis.

Monoclonal antibodies (MAbs) against Francisella tularensis were obtained. Three MAbs specifically reacted with F. tularensis, while four MAbs reacted with other members of the genus Francisella as well. Fluorescent isothiocyanate-conjugated MAbs unequivocally stained bacterial cells in specimens from experimentally infected mice. Two MAbs agglutinated F. tularensis antigen in the agglutination tests. These MAbs should improve methods for detection and identification of F. tularensis.

Animals↗
PubMed2006

Detection and isolation of highly pathogenic H5N1 avian influenza A viruses from blow flies collected in the vicinity of an infected poultry farm in Kyoto, Japan, 2004.

During the outbreak of highly pathogenic avian influenza that occurred in Tamba Town, Kyoto Prefecture in 2004, a total of 926 flies were collected from six sites within a radius of 2.3 km from the poultry farm. The H5 influenza A virus genes were detected from the intestinal organs, crop, and gut of the two blow fly species, Calliphora nigribarbis and Aldrichina grahami, by reverse transcription-polymerase chain reaction for the matrix protein (M) and hemagglutinin (HA) genes. The HA gene encoding multiple basic amino acids at the HA cleavage site indicated that this virus is a highly pathogenic strain. Based on the full-length sequences of the M, HA, and neuraminidase (NA) segments of virus isolates through embryonated chicken eggs, the virus from C. nigribarbis (A/blow fly/Kyoto/93/2004) was characterized as H5N1 subtype influenza A virus and shown to have > 99.9% identities in all three RNA segments to a strain from chickens (A/chicken/Kyoto/3/2004) and crows (A/crows/Kyoto/53/2004) derived during this outbreak period in Kyoto in 2004. Our results suggest it is possible that blow flies could become a mechanical transmitter of H5N1 influenza virus.

Amino Acid Sequence↗
PubMed2005

Identification of the MHC class I B locus in cynomolgus monkeys.

By determining the nucleotide sequences of more than 700 cDNA clones isolated from 16 cynomolgus monkeys, we identified 26 Mafa-B alleles. In addition, nine sequences with similarity to Mamu-I alleles were identified. Since multiple Mafa-B alleles were found in each individual, it was strongly suggested that the cynomolgus MHC class I B locus might be duplicated and that the Mafa-I locus was derived from the B locus by gene duplication, as in the case of the Mamu-I locus of rhesus monkeys.

Alleles↗
PubMed2004

Use of monoclonal antibodies for analyses of Coxiella burnetii major antigens.

Monoclonal antibodies (MAbs) to major antigens of Coxiella burnetii were produced. Some of the MAbs to a 62-kDa protein antigen, peptidoglycan protein complex and lipopolysaccharide (LPS) O-chains reacted with other bacteria whereas none of the MAbs to outer membrane proteins and LPS outer-core did. The LPS outer-core and OMPs may be useful antigens for specifically detecting antibodies to C. burnetii.

Antibodies, Bacterial↗
PubMed2003

SCID mouse model for lethal Q fever.

Q fever, a worldwide zoonosis caused by Coxiella burnetii, has many manifestations in humans. Endocarditis is the most serious complication of Q fever. Animal models are limited to acute pulmonary or hepatic disease and reproductive disorders. An appropriate experimental animal model for Q fever endocarditis does not yet exist. In this study, severe combined immunodeficient (SCID) mice infected with C. burnetii showed persistent clinical symptoms and died, whereas immunocompetent mice similarly infected became asymptomatic and survived. The SCID mice examined in this study had severe chronic lesions in their primary organs: the heart, lung, spleen, liver, and kidney. The heart lesions of the SCID mice were similar to those in humans with chronic Q fever endocarditis: they had focal calcification and expanded macrophages containing C. burnetii. The 50% lethal dose of C. burnetii in SCID mice was at least 10(8) times less than that in immunocompetent mice. The SCID mouse is highly susceptible to C. burnetii, and the immunodeficiency of the host enhances the severity of Q fever. This animal model could provide a new tool for the study of chronic Q fever and Q fever in immunodeficient hosts.

Animals↗
PubMed2002

Phase variation analysis of Coxiella burnetii during serial passage in cell culture by use of monoclonal antibodies.

Antigenic changes in Coxiella burnetii Nine Mile strain phase I during serial passages in cell culture were analyzed with three groups of monoclonal antibodies (MAbs) against lipopolysaccharide. The MAbs of group 1 did not react with organisms that were passaged over five times, and the MAbs of group 2 did not react with organisms that were passaged over eight times. The MAbs of group 3 reacted with organisms passaged up to 15 times but did not react with phase II cells. These results suggest that C. burnetii could be differentiated into four phase states during phase variation.

Animals↗