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.

  • [Show abstract] [Hide abstract]
    ABSTRACT: Primary immunodeficiencies have played a major role in the development of gene therapy for monogenic diseases of the bone marrow. The last decade has seen convincing evidence of long-term disease correction as a result of ex vivo viral vector-mediated gene transfer into autologous haematopoietic stem cells. The success of these early studies has been balanced by the development of vector-related insertional mutagenic events. More recently the use of alternative vector designs with self-inactivating designs, which have an improved safety profile has led to the initiation of a wave of new studies that are showing early signs of efficacy. The ongoing development of safer vector platforms and gene-correction technologies together with improvements in cell-transduction techniques and optimised conditioning regimes is likely to make gene therapy amenable for a greater number of PIDs. If long-term efficacy and safety are shown, gene therapy will become a standard treatment option for specific forms of PID.Gene Therapy advance online publication, 30 May 2013; doi:10.1038/gt.2013.21.
    Gene therapy 05/2013; · 4.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Invasive fungal infections have become a major cause of mortality in immunocompromised individuals. Despite the current availability of number of highly active antifungal agents, overall mortality remains around 40%. Importantly, it is clear that a failure to restore host immunity leads to worse outcomes. These observations provide clear rationale for the development of novel immunotherapies to improve outcomes in immunocompromised individuals with invasive fungal infections. In this article we summarise the key advances that have been made in the field of immunotherapy for fungal infections in recent years, with a particular focus on clinical studies of interferon-γ therapy, adoptive T cell therapy, and gene therapy for chronic granulomatous disorder. In addition a number of pre-clinical approaches are reviewed.
    Current opinion in microbiology 08/2012; 15(4):434-9. · 7.87 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Pattern recognition receptors (PRRs) are germline receptors that recognize conserved structures on microorganisms. Several PRRs have been identified in the recent years that are involved in the immune response against Aspergillus fumigatus. The role of PRRs in invasive pulmonary aspergillosis becomes especially apparent in the setting of an immunocompromised status of the host because of the redundancy of many PRRs in the host defense against A. fumigatus. Studies that investigated the PRRs and their effector pathways in invasive aspergillosis have led to a better understanding of the pathogenesis of invasive aspergillosis in immunocompromised patients. This knowledge may pave the way for novel diagnostic and immunomodulatory treatment strategies that are needed to overcome the high mortality associated with invasive A. fumigatus infection in immunocompromised patients.
    Annals of the New York Academy of Sciences 12/2012; 1273(1):60-7. · 4.38 Impact Factor

Full-text (2 Sources)

Available from
Jun 1, 2014