29 research outputs found
Cervicovaginal fluid and semen block the microbicidal activity of hydrogen peroxide produced by vaginal lactobacilli
BACKGROUND: H(2)O(2 )produced by vaginal lactobacilli is believed to protect against infection, and H(2)O(2)-producing lactobacilli inactivate pathogens in vitro in protein-free salt solution. However, cervicovaginal fluid (CVF) and semen have significant H(2)O(2)-blocking activity. METHODS: We measured the H(2)O(2 )concentration of CVF and the H(2)O(2)-blocking activity of CVF and semen using fluorescence and in vitro bacterial-exposure experiments. RESULTS: The mean H(2)O(2 )measured in fully aerobic CVF was 23 ± 5 μM; however, 50 μM H(2)O(2 )in salt solution showed no in vitro inactivation of HSV-2, Neisseria gonorrhoeae, Hemophilus ducreyii, or any of six BV-associated bacteria. CVF reduced 1 mM added H(2)O(2 )to an undetectable level, while semen reduced 10 mM added H(2)O(2 )to undetectable. Moreover, the addition of just 1% CVF supernatant abolished in vitro pathogen-inactivation by H(2)O(2)-producing lactobacilli. CONCLUSIONS: Given the H(2)O(2)-blocking activity of CVF and semen, it is implausible that H(2)O(2)-production by vaginal lactobacilli is a significant mechanism of protection in vivo
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Erratum: Consortium biology in immunology: The perspective from the Immunological Genome Project
Cervicovaginal fluid and semen block the microbicidal activity of hydrogen peroxide produced by vaginal lactobacilli
Abstract Background H2O2 produced by vaginal lactobacilli is believed to protect against infection, and H2O2-producing lactobacilli inactivate pathogens in vitro in protein-free salt solution. However, cervicovaginal fluid (CVF) and semen have significant H2O2-blocking activity. Methods We measured the H2O2 concentration of CVF and the H2O2-blocking activity of CVF and semen using fluorescence and in vitro bacterial-exposure experiments. Results The mean H2O2 measured in fully aerobic CVF was 23 ± 5 μM; however, 50 μM H2O2 in salt solution showed no in vitro inactivation of HSV-2, Neisseria gonorrhoeae, Hemophilus ducreyii, or any of six BV-associated bacteria. CVF reduced 1 mM added H2O2 to an undetectable level, while semen reduced 10 mM added H2O2 to undetectable. Moreover, the addition of just 1% CVF supernatant abolished in vitro pathogen-inactivation by H2O2-producing lactobacilli. Conclusions Given the H2O2-blocking activity of CVF and semen, it is implausible that H2O2-production by vaginal lactobacilli is a significant mechanism of protection in vivo.</p
Relationship between vigour and susceptibility of Austrian pine (Pinus nigra) to blister rust (Cronartium flaccidum)
High-risk human papillomavirus E7 expression reduces cell-surface MHC class I molecules and increases susceptibility to natural killer cells
CD56dimCD16high and CD56brightCD16− cell percentages associated with maximum knee extensor strength and incidence of death in elderly
Non-Hodgkin's lymphoma risk derived from exposure to organic solvents: a review of epidemiologic studies
Identification of transcriptional regulators in the mouse immune system.
The differentiation of hematopoietic stem cells into cells of the immune system has been studied extensively in mammals, but the transcriptional circuitry that controls it is still only partially understood. Here, the Immunological Genome Project gene-expression profiles across mouse immune lineages allowed us to systematically analyze these circuits. To analyze this data set we developed Ontogenet, an algorithm for reconstructing lineage-specific regulation from gene-expression profiles across lineages. Using Ontogenet, we found differentiation stage-specific regulators of mouse hematopoiesis and identified many known hematopoietic regulators and 175 previously unknown candidate regulators, as well as their target genes and the cell types in which they act. Among the previously unknown regulators, we emphasize the role of ETV5 in the differentiation of γδ T cells. As the transcriptional programs of human and mouse cells are highly conserved, it is likely that many lessons learned from the mouse model apply to humans