Restoration of anti-Aspergillus defense by neutrophil extracellular traps in human chronic granulomatous disease after gene therapy is calprotectin-dependent.

Division of Immunology/Hematology/BMT, University Children's Hospital Zurich, Zurich, Switzerland.
The Journal of allergy and clinical immunology (Impact Factor: 12.05). 03/2011; 127(5):1243-52.e7. DOI: 10.1016/j.jaci.2011.01.021
Source: PubMed

ABSTRACT Aspergillus spp infection is a potentially lethal disease in patients with neutropenia or impaired neutrophil function. We showed previously that Aspergillus hyphae, too large for neutrophil phagocytosis, are inhibited by reactive oxygen species-dependent neutrophil extracellular trap (NET) formation. This process is defective in chronic granulomatous disease (CGD) because of impaired phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase function.
To determine the antifungal agent and mechanism responsible for reconstitution of Aspergillus growth inhibition within NETs after complementation of NADPH oxidase function by gene therapy (GT) for CGD.
Antifungal activity of free and NET-released calprotectin was assessed by incubation of Aspergillus nidulans with purified calprotectin, induced NETs from human controls, and CGD neutrophils after GT in the presence or absence of Zn(2+) or α-S100A9 antibody, and with induced NETs from wild-type or S100A9(-/-) mouse neutrophils.
We identified the host Zn(2+) chelator calprotectin as a neutrophil-associated antifungal agent expressed within NETs, reversibly preventing A nidulans growth at low concentrations, and leading to irreversible fungal starvation at higher concentrations. Specific antibody-blocking and Zn(2+) addition abolished calprotectin-mediated inhibition of A nidulans proliferation in vitro. The role of calprotectin in anti-Aspergillus defense was confirmed in calprotectin knockout mice.
Reconstituted NET formation by GT for human CGD was associated with rapid cure of pre-existing therapy-refractory invasive pulmonary aspergillosis in vivo, underlining the role of functional NADPH oxidase in NET formation and calprotectin release for antifungal activity. These results demonstrate the critical role of calprotectin in human innate immune defense against Aspergillus infection.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This chapter summarizes the current state of the role of neutrophil extracellular traps in the modulation of fibrin assembly and the consequences regarding plasminogen activation and plasmin action.
    Fibrinolyisis and Thrombolysis, 1st edited by Krasimir Kolev, 05/2014: chapter 2: pages 31-59; Intech, Rijeka., ISBN: 978-953-51-1265-5
  • [Show abstract] [Hide abstract]
    ABSTRACT: Chronic Granulomatous Disease (CGD) is a primary immunodeficiency caused by abnormities in the NADPH Oxidase that is involved in the respiratory burst responsible for initiating the killing of microbes ingested by phagocytic cells. The hallmark of CGD is recurrent infection but the inflammatory complications can prove difficult to treat. New insights into the mechanisms responsible for the inflammatory complications have led to new therapies. The treatment of CGD colitis with an anti-tumour necrosis alpha agent has been shown to be successful but associated with significant infectious complications. Haematopoietic stem cell transplants offer the possibility of cure for those with ether a matched or unrelated donor transplant, with results of the latter improving significantly over recent years. Gene Therapy offers the promise of cure without the need for a transplant but better vectors are required.
    Journal of Infection 09/2014; · 4.02 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: To study if neutrophil extracellular traps (NETs) are present in the peritoneal fluid of endometriosis patients. NETs play a crucial role in fighting against microorganisms. However, exaggerated NET production may lead to tissue damage in their vicinity in pathological conditions. Our study evaluates the presence of NETs in endometriosis peritoneal fluid.Study designPeritoneal fluid (PF) was collected in a case-control study from 52 women, who underwent either diagnostic or operative laparoscopy. The control group consisted of 17 women with infertility, chronic pelvic pain, simple or functional cysts or irregular bleeding. The endometriosis group, altogether 35 patients, comprised 19 patients with stage I and II and 16 patients with stage III and IV endometriosis. First we tested whether the PF is able to stimulate NET production. Neutrophils from healthy volunteers were treated with the PF of endometriosis patients and controls and NETs were detected with Sytox orange extracellular DNA dye and immunofluorescence microscopy. Then we evaluated if NETs were already present in the collected PF using the specific myeloperoxidase (MPO)-DNA capture ELISA method, based on the MPO associated with the NET scaffold.ResultsThe PF of endometriosis patients did not stimulate NET release from healthy granulocytes. However, pre-existent NETs could be detected in 17 endometriosis patients out of 35 (49%). In contrary, in the control group NETs were present in only 3 patients out of 17 (18%), (p = 0.03, OR: 4.4). Moreover, the quantification of NETs showed a significantly higher amount of NETs in endometriosis compared to the controls (0.097 vs. 0.02, p = 0.04).Conclusion This is the first study, which evaluated and described the presence of NETs in the PF of endometriosis patients. Our study shows, that NETs may be involved in the complex pathophysiology of endometriosis.
    European Journal of Obstetrics & Gynecology and Reproductive Biology 10/2014; · 1.63 Impact Factor

Full-text (2 Sources)

Available from
Jun 1, 2014