Abstract:
:Strains H37Ra and H37Rv, attenuated and virulent variants, respectively, of the original human strain H37 of Mycobacterium tuberculosis, were used to infect cultures of mouse peritoneal macrophages. Bacterial viability of each strain was assessed over a 2-week period, and the cellular response to H37Ra during the first week was observed using electron microscopy. Prelabeling of secondary lysosomes with ferritin was used to facilitate the estimation of fusion of the lysosomes with phagosomes containing the bacteria. Streptomycin was excluded from the medium of cell cultures infected with H37Ra. The intracellular viability of strain H37Rv (in the presence of streptomycin) showed a lag during the first week after infection and then rose progressively to a mean figure seven times the starting level. In contrast, the viability of strain H37Ra declined, on the average, to one-fifth of the starting level during the first week; moreover, this decline occurred in the absence of antibiotics. In the second week a variable rise in the viable count took place, usually regaining the starting level. Electron microscopy of macrophages infected with H37Ra revealed a higher proportion of "damaged" bacteria 5 days after infection than at 1 day, in keeping with the decline in viability. Phagosomes containing these "damaged" (and presumed dead) organisms showed virtually universal fusion with prelabeled lysosomes. Phagosomes containing "intact" bacteria of this strain showed a prevalence of fusion varying from 38 to 56%, somewhat higher than the level previously reported for "intact" organisms of H37Rv. Nevertheless, the lysosome-phagosome fusion response to "intact" H37Ra was still far less extensive than that observed previously towards "intact" M. lepraemurium (around 90%). In conclusion, a difference between the macrophage lysosome-phagosome fusion response towards viable organisms of strain H37Ra and to the virulent strain H37Rv was observed, but was not pronounced, and the present findings are in keeping with the increasingly held view that H37Ra should be regarded as a low-virulence or attenuated strain rather than truly avirulent.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Hart PD,Armstrong JAdoi
10.1128/IAI.10.4.742-746.1974subject
Has Abstractpub_date
1974-10-01 00:00:00pages
742-6issue
4eissn
0019-9567issn
1098-5522journal_volume
10pub_type
杂志文章abstract::During the process of phagocytosis, human leukocytes emit a burst of luminescence which can be measured in a liquid scintillation spectrometer. The enzyme superoxide dismutase, which removes superoxide anions (O(2.)), inhibited this chemiluminescence by 70% at a concentration of 100 mug/ml. The enzyme did not inhibit ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:
更新日期:1974-06-01 00:00:00
abstract::Growth of a streptomycin-resistant strain of Escherichia coli (VL-2) in the presence of 30 microgram of streptomycin per ml resulted in the production by these bacteria of structurally altered, nonfunctional type 1 fimbriae. This strain, when grown in this subinhibitory concentration of streptomycin, became incapable ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.31.2.792-797.1981
更新日期:1981-02-01 00:00:00
abstract::Borrelia burgdorferi resembles gram-negative bacteria in having both cellular and outer membranes. We previously showed that a lipopolysaccharide (LPS)-like material could be extracted from B. burgdorferi with phenol-chloroform-petroleum ether (PCP). The PCP extract of B. burgdorferi exhibited biological activity in s...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.12.4995-5003.1992
更新日期:1992-12-01 00:00:00
abstract::Immunoglobulin class-specific antibodies were measured by a solid-phase radioimmunoassay in serum, bronchoalveolar washings (BAW), lung cell lysates, and spleen cell lysates in germfree mice after intranasal (i.n.) and intraperitoneal (i.p.) primary and secondary 10(5), 10(4), and 10(3) mean tissue culture infective d...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.17.3.521-527.1977
更新日期:1977-09-01 00:00:00
abstract::Mycoplasma arthritidis induces an acute to chronic arthritis in rodents. Arthritis induced in mice histologically resembles human rheumatoid arthritis and can be associated with lethal toxicity following systemic injection. The M. arthritidis mitogen (MAM) superantigen has long been implicated as having a role in path...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00667-08
更新日期:2008-11-01 00:00:00
abstract::Salmonella enterica serovar Typhimurium employs two different type III secretion systems (TTSS) encoded within Salmonella pathogenicity islands 1 and 2 (SPI1 and SPI2) for targeting of effector proteins into the cytosol of eukaryotic cells during different stages of the infection cycle. The SPI1 TTSS translocates viru...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.73.1.334-341.2005
更新日期:2005-01-01 00:00:00
abstract::The important veterinary pathogen Clostridium perfringens type B is unique for producing the two most lethal C. perfringens toxins, i.e., epsilon-toxin and beta-toxin. Our recent study (K. Miyamoto, J. Li, S. Sayeed, S. Akimoto, and B. A. McClane, J. Bacteriol. 190:7178-7188, 2008) showed that most, if not all, type B...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00838-09
更新日期:2010-01-01 00:00:00
abstract::Ribosomal subunits from Mycobacterium smegmatis were analyzed by using sedimentation velocity, sedimentation equilibrium, and acrylamide gel electrophoresis experiments. These s(20.w) values for the subunits are 48.7S and 28.1S. The molecular weight of the 49S subunit is about 1.65 x 10(6), and that of the 28S subunit...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.9.3.489-496.1974
更新日期:1974-03-01 00:00:00
abstract::Six strains of Rickettsia rickettsii from Montana and North Carolina were examined in an effort to identify rickettsial constituents associated with virulence. Fever responses, scrotal reactions, and mortalities of male guinea pigs inoculated intraperitoneally with 1,000 PFU of rickettsial strains revealed that the tw...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.44.3.559-564.1984
更新日期:1984-06-01 00:00:00
abstract::Staphylococcus epidermidis is a leading cause of infections associated with indwelling medical devices, including prosthetic joint infection. While biofilm formation is assumed to be the main mechanism underlying the chronic infections S. epidermidis causes, we hypothesized that S. epidermidis also evades immune killi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00237-18
更新日期:2018-09-21 00:00:00
abstract::Streptococcus mutans, a major pathogen of dental caries, is considered one of the causative agents of infective endocarditis (IE). Recently, bacterial DNA encoding 120-kDa cell surface collagen-binding proteins (CBPs) has frequently been detected from S. mutans-positive IE patients. In addition, some of the CBP-positi...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00401-17
更新日期:2017-11-17 00:00:00
abstract::Treatment with nontoxic monophosphoryl lipid A (MPL), which was derived from a polysaccharide-deficient, heptoseless Re mutant of Salmonella typhimurium, was found to inactivate suppressor T-cell activity, as evidenced by a decrease in the degree of low-dose immunological paralysis expressed and an increase in the mag...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.5.1076-1083.1988
更新日期:1988-05-01 00:00:00
abstract::While gamma/delta T cells are involved in host defense and immunopathology in a variety of infectious diseases, their precise role is not yet clearly defined. In the absence of gamma/delta T cells, mice die after infection with a dose of Listeria monocytogenes that is not lethal in immunologically intact animals. Morb...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.12.7213-7223.2001
更新日期:2001-12-01 00:00:00
abstract::The ability of the endospore-forming, gram-positive bacterium Bacillus anthracis to survive in activated macrophages is key to its germination and survival. In a previous publication, we discovered that exposure of primary murine macrophages to B. anthracis endospores upregulated NOS 2 concomitant with an .NO-dependen...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00283-07
更新日期:2007-08-01 00:00:00
abstract::A persistent Staphylococcus epidermidis infection in mice around a subcutaneous polyvinylpyrrolidone-grafted silicon elastomer catheter (SEpvp) but not around a conventional silicon elastomer catheter was observed. With SEpvp pericatheter tissue, protracted and exaggerated interleukin-1beta (IL-1beta) production was f...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.3.1692-1695.2000
更新日期:2000-03-01 00:00:00
abstract::Candida albicans biofilms are formed through three distinct developmental phases and are associated with high fluconazole (FLU) resistance. In the present study, we used a set of isogenic Candida strains lacking one or more of the drug efflux pumps Cdr1p, Cdr2p, and Mdr1p to determine their role in FLU resistance of b...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.8.4333-4340.2003
更新日期:2003-08-01 00:00:00
abstract::Antibiotic-resistant recombinants obtained from mating antibiotic-resistant Escherichia coli with virulent, antibiotic-sensitive Salmonella typhimurium are generally avirulent. After 32 consecutive transfers, two of four avirulent recombinants regained their virulence without loss of episome-mediated resistance. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.2.4.516-518.1970
更新日期:1970-10-01 00:00:00
abstract::A cytoplasmic 75-kDa immunogen from Chlamydia trachomatis serovar L2 has previously been characterized as being similar to the Escherichia coli heat shock protein DnaK. We have localized a linear epitope for one monoclonal antibody specific for C. trachomatis DnaK. By use of a recombinant DNA technique, the epitope wa...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.5.2051-2057.1994
更新日期:1994-05-01 00:00:00
abstract::We have previously reported that a wild strain of Francisella tularensis is much less efficiently killed by human polymorphonuclear leukocytes than is an attenuated strain. In the present study, the killing of the attenuated strain was found to be strictly oxygen dependent. The wild and the attenuated strains both ind...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.43.2.730-734.1984
更新日期:1984-02-01 00:00:00
abstract::Neisseria meningitidis crosses the blood-brain barrier (BBB) following the activation of the β2-adrenergic receptor by the type IV pili (TFP). Two components of the type IV pili recruit the β2-adrenergic receptor, the major pilin PilE and the minor pilin PilV. Here, we report that a strain deleted of PilX, one of the ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00369-12
更新日期:2012-09-01 00:00:00
abstract::Human genital Chlamydia infection is a major public health concern due to the serious reproductive system complications. Chlamydia binds several receptor tyrosine kinases (RTKs) on host cells, including the epidermal growth factor receptor (EGFR), and activates cellular signaling cascades for host invasion, cytoskelet...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00819-19
更新日期:2020-03-23 00:00:00
abstract::Escherichia coli strains expressing the K1 capsule are a major cause of sepsis and meningitis in human neonates. The development of these diseases is dependent on the expression of a range of virulence factors, many of which remain uncharacterized. Here, we show that all but 1 of 34 E. coli K1 neonatal isolates carrie...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00716-15
更新日期:2015-09-01 00:00:00
abstract::In studies of experimental Lyme disease, a major obstacle has been the unavailability of a suitable animal model. We found that irradiated LSH/Ss Lak hamsters developed arthritis after injection of Borrelia burgdorferi in the hind paws. When nonirradiated hamsters were injected in the hind paws with B. burgdorferi, ac...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.56.9.2336-2342.1988
更新日期:1988-09-01 00:00:00
abstract::Human systemic antibody levels to oral members of the Bacteroides genus were assessed with an enzyme-linked immunosorbent assay. Antibody levels to B. gingivalis, two homology groups of B. intermedius, B. melaninogenicus, B. denticola, B. loescheii, B. corporis, B. oralis, B. buccae, and B. gracilis were determined in...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.51.2.507-513.1986
更新日期:1986-02-01 00:00:00
abstract::The availability of relevant and useful animal models is critical for progress in the development of effective vaccines and therapeutics. The infection of rabbits and non-human primates with fully virulent Bacillus anthracis spores provides two excellent models of anthrax disease. However, the high cost of procuring a...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.01875-06
更新日期:2007-06-01 00:00:00
abstract::Human lactoferrin (hLf), a glycoprotein released from neutrophil granules during inflammation, and the lipopolysaccharide (LPS)-binding protein (LBP), an acute-phase serum protein, are known to bind to the lipid A of LPS. The LPS-binding sites are located in the N-terminal regions of both proteins, at amino acid resid...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.2.486-491.1998
更新日期:1998-02-01 00:00:00
abstract::Active immunization with Porphyromonas gingivalis whole-cell preparations has been shown to prevent P. gingivalis infection and oral bone loss. Employing passive antibody transfer and opsonization, we demonstrate with this study that immunization-elicited P. gingivalis-specific immunoglobulin G facilitates clearance o...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.72.4.2408-2411.2004
更新日期:2004-04-01 00:00:00
abstract::Antimicrobial peptides (AMPs), such as β-defensins and cathelicidins, are essential components of innate and adaptive immunity owing to their extensive multifunctional activities. However, their role in fungal infection in vivo remains elusive. In this study, we investigated the protective effect of murine β-defensin ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00179-13
更新日期:2013-08-01 00:00:00
abstract::Patients with chronic mucocutaneous candidiasis (CMC) are selectively unable to clear the yeast Candida, which results in persistent debilitating infections affecting the skin, nails, and mucous membranes. The underlying defect is unknown. Recent animal studies highlighted the importance of type 1 cytokines in protect...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.10.5690-5699.2003
更新日期:2003-10-01 00:00:00
abstract::The recent finding that high numbers of strict anaerobes are present in the respiratory tract of cystic fibrosis (CF) patients has drawn attention to the pathogenic contribution of the CF microbiome to airway disease. In this study, we investigated the specific interactions of the most dominant bacterial CF pathogen, ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.02234-14
更新日期:2015-01-01 00:00:00