Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.25.1 (
deoxyribonuclease
)
1,471
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The ability of sonicates and subcellular fractions of the intracellular parasite Toxoplasma gondii to enhance in vitro human natural killer (NK) cell activity was examined. Incubation of nylon-wool-non-adherent human peripheral blood lymphocytes (PBL) with sonicates of T. gondii for 18-72 hr resulted in increased NK activity against an NK-sensitive, as well as an insensitive, target cell. Single-cell assays revealed that augmentation of NK activity was not due to an increased binding of K562 target cells to effector cells. Differential centrifugation studies indicated that NK-augmenting activity was distributed in membrane-enriched and cytoplasmic fractions. This activity was found to be resistant to treatment with ribonuclease (RNase) and
deoxyribonuclease
(
DNase
), but susceptible to proteolysis. Antibodies present in the serum of humans infected with Toxoplasma blocked the NK cell-augmenting effect of the membrane-enriched fractions. Enhancement of NK activity by PBL incubated with Toxoplasma sonicate was accompanied by a concomitant increase in interferon (IFN), but not of
interleukin 2
(
IL-2
), levels in supernatants of the cell cultures.
...
PMID:Enhancement of human natural killer cell activity by subcellular components of Toxoplasma gondii. 658 35
Intramuscular injection of naked plasmid DNA is known (1-3) to elicit humoral and cell-mediated immune responses against the encoded antigen. It is thought (2,3) that immunity follows DNA uptake by muscle cells, leading to the expression and extracellular release of the antigen which is then taken up by antigen presenting cells (APC). In addition, it is feasible that some of the injected DNA is taken up directly by APC. Disadvantages (1-3) of naked DNA vaccination include: uptake of DNA by only a minor fraction of muscle cells, exposure of DNA to
deoxyribonuclease
in the interstitial fluid thus necessitating the use of relatively large quantities of DNA, and, in some cases, injection into regenerating muscle in order to enhance immunity. We have recently proposed (1,4) that DNA immunization via liposomes (phospholipid vesicles) could circumvent the need of muscle involvement and instead facilitate (5) uptake of DNA by APC infiltrating the site of injection or in the lymphatics, at the same time protecting DNA from nuclease attack (6). Moreover, transfection of APC with liposomal DNA could be promoted by the judicial choice of vesicle surface charge, size and lipid composition, or by the co-entrapment, together with DNA, of plasmids expressing appropriate cytokines (e.g.,
interleukin 2
), or immunostimulatory sequences.
...
PMID:Entrapment of plasmid DNA vaccines into liposomes by dehydration/rehydration. 2137 30
