Abstract:
:A plaque assay system for pathogenic rickettsiae, which utilizes primary chick embryo tissue cultures, is described. It proved to be a highly reproducible measure of infectiousness for Rickettsia rickettsi and R. typhi, which were employed in most studies; as well as for R. canada, R. prowazeki, R. sibirica, R. akari, R. conori, and Coxiella burneti. Plaque-forming units (PFU) were compared to direct rickettsial counts and to 50% infectious dose (ID(50)) values for embryonated eggs, mice, and guinea pigs. Plaque size, appearance, and number were influenced by diluent, incubation temperature after nutrient overlay, centrifugation of inoculated tissue cultures, and number of host cells planted initially in each flask. The most critical factors in plaque formation were diluent used in making rickettsial suspensions and incubation temperature (32 C) after nutrient overlay. Brain Heart Infusion was the only diluent capable of preventing significant delay in plaque formation and decreases in PFU and mouse ID(50). Plaque formation was unaffected by genetic background of host cells, volume of inoculum, temperature and length of incubation period before nutrient overlay, and rapid freezing and thawing of rickettsial seed. Centrifugation of inoculated cultures at 600 x g resulted in 100% irreversible absorption of rickettsiae to host cells within 5 min, whereas without centrifugation at least 4 hr was required to achieve the same effect.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Wike DA,Tallent G,Peacock MG,Ormsbee RAdoi
10.1128/IAI.5.5.715-722.1972subject
Has Abstractpub_date
1972-05-01 00:00:00pages
715-22issue
5eissn
0019-9567issn
1098-5522journal_volume
5pub_type
杂志文章abstract::A zone of extracellular digestion of the mucin layer around Candida albicans blastoconidia was observed by transmission electron microscopy in the jejunum of mice inoculated intragastrically (G. T. Cole, K. R. Seshan, L. M. Pope, and R. J. Yancey, J. Med. Vet. Mycol. 26:173-185, 1988). This observation prompted the hy...
journal_title:Infection and immunity
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doi:10.1128/IAI.64.11.4514-4519.1996
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journal_title:Infection and immunity
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doi:10.1128/IAI.10.5.1189-1191.1974
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journal_title:Infection and immunity
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doi:10.1128/IAI.63.6.2120-2125.1995
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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doi:10.1128/IAI.00403-18
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doi:10.1128/iai.70.2.612-619.2002
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.39.2.565-568.1983
更新日期:1983-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.21.2.546-555.1978
更新日期:1978-08-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.56.9.2437-2442.1988
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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doi:10.1128/IAI.60.3.845-852.1992
更新日期:1992-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.10.4119-4125.1993
更新日期:1993-10-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.48.3.824-831.1985
更新日期:1985-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.8.3576-3579.1994
更新日期:1994-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.48.3.839-842.1985
更新日期:1985-06-01 00:00:00
abstract::The tetrasaccharide 3-deoxy-alpha-D-manno-2-octulosonic acid (alpha-KDO) (2----8)-alpha-KDO(2----4)-alpha-KDO(2----6)-beta GlcNAc, a partial structure of chlamydial lipopolysaccharide (LPS) representing a genus-specific epitope, was synthesized and covalently linked to bovine serum albumin, resulting in an artificial ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.4.1314-1321.1992
更新日期:1992-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.57.12.3863-3868.1989
更新日期:1989-12-01 00:00:00
abstract::The derivative toxins purified from cultures of proteolytic strains of Clostridium botulinum types A and F were found to have been only partially nicked but were fully activated. Trypsinization of C. botulinum type B derivative toxin at pH 6.0 resulted in simultaneous activation and nicking, whereas at pH 4.5, activat...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.2.402-407.1977
更新日期:1977-08-01 00:00:00
abstract::The recent development of acellular pertussis vaccines has been a significant improvement in the conventional whole-cell diphtheria-pertussis-tetanus toxoid vaccines, but high production costs will limit its widespread use in developing countries. Since Mycobacterium bovis BCG vaccination against tuberculosis is used ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.9.4877-4883.2000
更新日期:2000-09-01 00:00:00