Human Vγ9Vδ2 T cells exhibit antifungal activity against Aspergillus fumigatus and other filamentous fungi.

Invasive aspergillosis (IA) and mucormycosis are life-threatening diseases, especially among immunocompromised patients. Drug-resistant Aspergillus fumigatus strains have been isolated worldwide, which can pose a serious clinical problem. As IA mainly occurs in patients with compromised immune systems, the ideal therapeutic approach should aim to bolster the immune system. In this study, we focused on Vγ9Vδ2 T cells that exhibit immune effector functions and examined the possibility of harnessing this unconventional T cell subset as a novel therapeutic modality for IA. A potent antifungal effect was observed when A. fumigatus (Af293) hyphae were challenged by Vγ9Vδ2 T cells derived from peripheral blood. In addition, Vγ9Vδ2 T cells exhibited antifungal activity against hyphae of all Aspergillus spp., Cunninghamella bertholletiae, and Rhizopus microsporus but not against their conidia. Furthermore, Vγ9Vδ2 T cells also exhibited antifungal activity against azole-resistant A. fumigatus, indicating that Vγ9Vδ2 T cells could be used for treating drug-resistant A. fumigatus. The antifungal activity of Vγ9Vδ2 T cells depended on cell-to-cell contact with A. fumigatus hyphae, and degranulation characterized by CD107a mobilization seems essential for this activity against A. fumigatus. Vγ9Vδ2 T cells could be developed as a novel modality for treating IA or mucormycosis. IMPORTANCE: Invasive aspergillosis (IA) and mucormycosis are often resistant to treatment with conventional antifungal agents and have a high mortality rate. Additionally, effective antifungal treatment is hindered by drug toxicity, given that both fungal and human cells are eukaryotic, and antifungal agents are also likely to act on human cells, resulting in adverse effects. Therefore, the development of novel therapeutic agents specifically targeting fungi is challenging. This study demonstrated the antifungal activity of Vγ9Vδ2 T cells against various Aspergillus spp. and several Mucorales in vitro and discussed the mechanism underlying their antifungal activity. We indicate that adoptive immunotherapy using Vγ9Vδ2 T cells may offer a new therapeutic approach to IA.

Novel method of attaching a suction tube externally to a tracheal tube as an insertion route for a Fogarty catheter in cryobiopsy: Retrospective comparative study.

BACKGROUND: Cryobiopsy use is anticipated to become more common in diagnosing lung diseases. In Japan, inserting a Fogarty catheter through a suction channel above the endotracheal tube's cuff for hemostasis is common practice. However, the rigid nature of the endotracheal tube poses challenges to tracheal intubation using a bronchoscope. The endotracheal tube cuff must be removed to prevent interference during Fogarty catheter insertion. To simplify the procedure and enhance safety, we devised and implemented a method of inserting a hemostatic Fogarty catheter with a suction tube externally attached to a softer endotracheal tube. This study aimed to evaluate the sustainability of this Fogarty catheter insertion method using suction tubes. METHODS: The hemostatic Fogarty catheter insertion method was retrospectively validated. We compared outcomes between 60 patients who underwent the conventional method with a suction channel above the cuff and 50 patients who underwent the novel approach with an externally attached suction tube. RESULTS: The physicians performing bronchoscopy and inserting the Fogarty catheter in the group in which the suction tube was externally attached for Fogarty catheter insertion had little experience. However, the overall bronchoscopy time was shorter; the two groups showed no significant differences in complications. CONCLUSION: Regarding cryobiopsy procedures, using an externally attached suction tube for Fogarty catheter insertion was practical and comparable to the conventional method of using a suction channel above the cuff. This method made the procedure more simple and safe.