PubMed · 491106
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
Y Kagosaki. 1979-06-29. [Intracellular bactericidal activity].. https://pubmed.ncbi.nlm.nih.gov/491106/
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
In response to concern about Yersinia enterocolitica contamination of blood products, we have studied the effects on Y enterocolitica growth of holding whole blood at 22 degrees C for 20 h and then removing leucocytes. Thirty pools of three bags of blood were inoculated with Y enterocolitica (2 x 10(1)-3 x 10(4) colony-forming units/ml). One bag in each pool was processed to red-blood-cell concentrate after 6 h at 4 degrees C (RBC); the other two were held at 22 degrees C for 20 h before processing to buffy-coat-depleted RBC (BCd-RBC). One of these bags was then depleted of leucocytes by filtration (Ld-RBC). All bags were stored at 4 degrees C for 5 weeks. RBC bags showed Y enterocolitica growth after the shortest storage times, followed by BCd-RBC then Ld-RBC (p less than 0.03-0.001). We recommend that whole blood should be held at 22 degrees C to make use of inherent bactericidal activity; leucocytes should then be removed.
The bactericidal power of fresh human plasma against Klebsiella pneumoniae and Escherichia coli was extremely sensitive to changes in Eh and pH. At a high Eh (approx. +200 mV) the bacteria were destroyed, but rapid regrowth occurred when the Eh was lowered to approx. -400 mV. Abolition of the bactericidal effect was also produced by adding ferric iron at a high Eh (approx. +200 mV). Lowering the pH to 6.50 reduced or prevented the bactericidal effect. These results are probably related to the availability of iron for bacterial growth, and could be important for understanding the development of infection in injured or diseased tissue.
A mutant unable to bind a monoclonal antibody (mAb 1E6) directed against serogroup 1 lipopolysaccharide (LPS) was isolated from L. pneumophila strain Philadelphia-1. SDS-PAGE analysis of isolated LPS from the mutant and wild type revealed that there were no obvious structural differences between the two LPS. The results from Western-blot experiments showed that the mutant LPS was unable to bind mAb 1E6 but retained the ability to bind polyclonal serogroup 1 antibodies. Loss of the LPS epitope recognized by mAb 1E6 did not alter the ability of the mutant to multiply in human monocyte-like U937 cells. Also, the mutant, like wild type, was resistant to killing by normal human serum. These results show that a minor change in the antigenic composition of serogroup 1 LPS has no effect on the virulence properties of strain Philadelphia-1. Additionally, this mutant may be useful for molecular genetic analysis of serogroup 1 LPS biosynthesis and assembly.