Pharmacodynamics of recombinant human DNase I in serum

Prince, William S.; Baker, Dana Lee; Dodge, Anthony; Ahmed, Ashfaq; Chestnut, R W; Sinicropi, Dominick

doi:10.1046/j.1365-2249.1998.00647.x

Cited by 66 publications

(50 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…It is important to refer to the activity of DNase I in the serum and not the serum concentration of DNase I, since various DNase inhibitors are present in the sera of healthy persons (28). We performed chromatin-degradation assays to examine the DNase activity in AS.…”

Section: Methodsmentioning

confidence: 99%

Cooperation between C1q and DNase I in the clearance of necrotic cell–derived chromatin

Gaipl¹,

Beyer²,

Heyder³

et al. 2004

Arthritis & Rheumatism

105

View full text Add to dashboard Cite

Objective. The efficient uptake of dying cells by phagocytes is essential to the avoidance of chronic inflammation. Some human autoimmune responses are thought to be driven by autoantigens from apoptotic or necrotic cells. We analyzed the role of C1q and DNase I in the disposal of necrotic cell-derived chromatin because deficiencies in these serum factors predispose to the development of systemic autoimmune disorders, such as systemic lupus erythematosus.Methods. Human necrotic peripheral blood lymphocytes were incubated in cell culture medium supplemented with various sera or serum components. Chromatin degradation was monitored by measuring the residual DNA content by flow cytometry. The uptake of necrotic cell-derived nuclei was analyzed by in vitro phagocytosis assays.Results. Reconstitution of C1q-depleted serum with C1q strongly increased its ability to degrade necrotic cell-derived chromatin. Although C1q itself displayed no DNase activity, it strongly augmented the activity of serum DNase I. Whereas an excess of recombinant DNase I degraded chromatin in the absence of C1q, efficient uptake of the predigested material by monocyte-derived phagocytes required the presence of C1q. These data show that C1q and DNase I cooperate in the degradation of chromatin from necrotic cells. Furthermore, C1q was found to be necessary for effective uptake of degraded chromatin by monocyte-derived phagocytes.Conclusion. C1q or DNase I deficiencies may precipitate autoimmunity in humans by a mechanism similar to that of other molecules that are involved in the safe, efficient, and rapid disposal of dying cells.

show abstract

Section: Methodsmentioning

confidence: 99%

Cooperation between C1q and DNase I in the clearance of necrotic cell–derived chromatin

Gaipl¹,

Beyer²,

Heyder³

et al. 2004

Arthritis & Rheumatism

105

View full text Add to dashboard Cite

show abstract

“…It may well be that CMV DNA is present in these specimens in an unprotected form, vulnerable to DNA-degrading enzymes (DNases), rather than in a protected form within the enveloped viral capsid. Since serum is rich in DNases (17,23), such unprotected DNA may be degraded further during and following the clotting process. On the other hand, unprotected CMV DNA present in plasma that is anticoagulated with EDTA is expected to be stabilized, since DNases need bivalent cations for activity.…”

mentioning

confidence: 99%

Human Cytomegalovirus DNA in Plasma and Serum Specimens of Renal Transplant Recipients Is Highly Fragmented

Boom¹,

Sol²,

Schuurman³

et al. 2002

J Clin Microbiol

View full text Add to dashboard Cite

Quantitation of cytomegalovirus (CMV) DNA in plasma and serum by PCR is increasingly used to identify patients at risk for developing CMV disease and to monitor the efficacy of antiviral therapy. Although CMV DNA levels are generally interpreted as viral loads, the exact nature of the viral DNA in these specimens is unknown. We studied the state of CMV DNA in plasma and serum specimens obtained from three renal transplant recipients at peak viral DNA levels during primary CMV infection. For this purpose, DNA isolated from these specimens was fractionated by size, and CMV DNA levels in the resulting DNA fractions were measured by quantitative PCR targeted at large (578-bp) and small (134-bp) amplicons. These experiments showed that the molecular sizes of DNA fragments from which CMV DNA is amplified were small (<2,000 bp), indicating that CMV DNA in plasma and serum is highly fragmented. Furthermore, CMV DNA levels were consistently higher when targeted at the smaller amplicon, providing additional evidence for the fragmentation of viral DNA. In conclusion, the first results with three patients have shown that CMV DNA in plasma and serum is highly fragmented and does not necessarily reflect the amount of infectious virus. These observations have potential consequences for understanding CMV pathogenesis and interpreting CMV DNA levels in individual patient management.Infection with cytomegalovirus (CMV) (human herpesvirus 5) is an important cause of morbidity and mortality in immunocompromised individuals, such as transplant recipients and AIDS patients. In the management of CMV infection, preemptive treatment strategies, aimed at preventing CMV disease in high-risk patients, are receiving increasing attention. For the benefit of such strategies, quantitative detection of CMV DNA in the blood compartment by PCR is increasingly used to identify patients at risk for CMV disease. In addition, measurements of viral DNA load may be important for monitoring the efficacy of antiviral treatment and predicting the development of drug resistance (3,22,27).The genome of human CMV consists of a large (about 230,000-bp) double-stranded linear DNA molecule which is encapsidated within a double protein shell and a lipid envelope (24). Most of the CMV DNA in the blood compartment is present in abortively infected polymorphonuclear leukocytes (4,12,16,26); less DNA is found in peripheral blood mononuclear cells, part of which, upon differentiation into macrophages, support viral replication (12,26,28). In addition, circulating, productively infected endothelial cells may be a source of CMV DNA (16, 18). CMV DNA can also be detected in serum and plasma, which are convenient specimens for CMV DNA load measurement (10,15,19,29). In recent years, many studies on the qualitative and quantitative detection of CMV DNA in these specimens have been reported, which generally show that levels of CMV DNA found in plasma or serum are significantly lower than those found in white blood cells (4,5,13,15,33).At present, it is unclear whether CMV ...

show abstract

“…Firstly, because of the high sensitivity of the PCR method even minimal residues of uncleaved DNA yield positive results. Secondly, it has been suggested that the sodium concentration in human serum might decrease human DNAase activity [7,18]. Finally, a protective effect of histone-like proteins against degradation by DNAases has been described in genomic E. coli DNA sequences [19], whereas synthetic oligodeoxynucleotides lack these protective compounds.…”

Section: Discussionmentioning

confidence: 99%

“…In a second set of experiments, the quantitative ratio of DNAase to DNA in the samples was varied by adding recombinant human DNAase (rhDNAase; HoffmannLaRoche, Grenzach-Wyhlen, Germany), which is considered to be equivalent to human serum DNAase I [7,10]. Ten human serum samples were incubated with 30 pg of puri®ed E. coli DNA and either 30 ng or 30 ìg of rhDNAase I (®nal volume 0.1 ml) and then processed as described above.…”

Section: E Coli and Pcrmentioning

confidence: 99%

The effect of human serum DNAases on the ability to detect antibiotic-killed Escherichia coli in blood by PCR

Heininger¹,

Ulrich

Priebe

et al. 2001

Journal of Medical Microbiology

View full text Add to dashboard Cite

PCR has proved superior to conventional blood culture for diagnosing bacteraemia in the presence of antibiotics. Nevertheless, even PCR might yield false-negative results if the template DNA were to be cleaved by serum DNAases after antibiotics had induced bacterial death. To evaluate the cleavage of bacterial template DNA by human serum DNAase I, serum samples inoculated with puri®ed Escherichia coli DNA were incubated with increasing amounts of recombinant human DNAase (rhDNAase) and then examined by a PCR speci®c for E. coli. As a prerequisite of potential DNAase attack, the release of E. coli DNA after antibiotic-induced bacterial death was quanti®ed by¯uorescence microscopy and¯ow cytometry. Finally, the in¯uence of rhDNAase on the PCR-based detection of antibiotic-killed E. coli in serum was assessed. The results indicated that puri®ed E. coli DNA is remarkably stable in human serum; positive PCR results did not decrease signi®cantly until the ratio of recombinant human DNAase I:E. coli rose to 10 6 :1. As only 14.8±28.4% of the total E. coli DNA was released after antibiotic killing, the PCR-based detection of E. coli fell by only 10% when cefotaxime-killed E. coli were incubated with rhDNAase. It was concluded that human serum DNAases and antibiotic killing do not compromise the reliability of PCR examinations for bacteraemia.

show abstract

Pharmacodynamics of recombinant human DNase I in serum

Cited by 66 publications

References 28 publications

Cooperation between C1q and DNase I in the clearance of necrotic cell–derived chromatin

Cooperation between C1q and DNase I in the clearance of necrotic cell–derived chromatin

Human Cytomegalovirus DNA in Plasma and Serum Specimens of Renal Transplant Recipients Is Highly Fragmented

The effect of human serum DNAases on the ability to detect antibiotic-killed Escherichia coli in blood by PCR

Contact Info

Product

Resources

About