Refine
Document Type
- Article (3)
Language
- English (3)
Has Fulltext
- yes (3)
Is part of the Bibliography
- no (3)
Keywords
- Aspergillus fumigatus (1)
- Children (1)
- FungiScope® registry (1)
- Immune response (1)
- Immunity (1)
- Immunology and Microbiology Section (1)
- Invasive fungal infections (1)
- Lomentospora prolificans (1)
- Pediatric patients (1)
- Scedosporium spp. (1)
Institute
- Medizin (3)
DCs express intrinsic cellular defense mechanisms to specifically inhibit HIV-1 replication. Thus, DCs are productively infected only at very low levels with HIV-1, and this non-permissiveness of DCs is suggested to go along with viral evasion. We now illustrate that complement-opsonized HIV-1 (HIV-C) efficiently bypasses SAMHD1 restriction and productively infects DCs including BDCA-1 DCs. Efficient DC infection by HIV-C was also observed using single-cycle HIV-C, and correlated with a remarkable elevated SAMHD1 T592 phosphorylation but not SAMHD1 degradation. If SAMHD1 phosphorylation was blocked using a CDK2-inhibitor HIV-C-induced DC infection was also significantly abrogated. Additionally, we found a higher maturation and co-stimulatory potential, aberrant type I interferon expression and signaling as well as a stronger induction of cellular immune responses in HIV-C-treated DCs. Collectively, our data highlight a novel protective mechanism mediated by complement opsonization of HIV to effectively promote DC immune functions, which might be in the future exploited to tackle HIV infection.
Objectives: Current knowledge on infections caused by Scedosporium spp. and Lomentospora prolificans in children is scarce. We therefore aim to provide an overview of risk groups, clinical manifestation and treatment strategies of these infections.
Methods: Pediatric patients (age ≤18 years) with proven/probable Scedosporium spp. or L. prolificans infection were identified in PubMed and the FungiScope® registry. Data on diagnosis, treatment and outcome were collected.
Results: Fifty-five children (median age 9 years [IQR: 5–14]) with invasive Scedosporium spp. (n = 33) or L. prolificans (n = 22) infection were identified between 1990 and 2019. Malignancy, trauma and near drowning were the most common risk factors. Infections were frequently disseminated. Most patients received systemic antifungal therapy, mainly voriconazole and amphotericin B, plus surgical treatment.
Overall, day 42 mortality was 31%, higher for L. prolificans (50%) compared to Scedosporium spp. (18%). L. prolificans infection was associated with a shorter median survival time compared to Scedosporium spp. (6 days [IQR: 3–28] versus 61 days [IQR: 16–148]). Treatment for malignancy and severe disseminated infection were associated with particularly poor outcome (HR 8.33 [95% CI 1.35–51.40] and HR 6.12 [95% CI 1.52–24.66], respectively). Voriconazole use at any time and surgery for antifungal treatment were associated with improved clinical outcome (HR 0.33 [95% CI 0.11–0.99] and HR 0.09 [95% CI 0.02–0.40], respectively).
Conclusions: Scedosporium spp. and L. prolificans infections in children are associated with high mortality despite comprehensive antifungal therapy. Voriconazole usage and surgical intervention are associated with successful outcome.
Natural Killer (NK) cells are active against Aspergillus fumigatus, which in turn is able to impair the host defense. Unfortunately, little is known on the mutual interaction of NK cells and A. fumigatus. We coincubated human NK cells with A. fumigatus hyphae and assessed the gene expression and protein concentration of selected molecules. We found that A. fumigatus up-regulates the gene expression of pro-inflammatory molecules in NK cells, but inhibited the release of these molecules resulting in intracellular accumulation and limited extracellular availability. A. fumigatus down-regulatedmRNA levels of perforin in NK cells, but increased its intra- and extracellular protein concentration. The gene expression of stress related molecules of A. fumigatus such as heat shock protein hsp90 was up-regulated by human NK cells. Our data characterize for the first time the immunosuppressive effect of A. fumigatus on NK cells and may help to develop new therapeutic antifungal strategies.