Stimulation of isolated CD4+ and CD8+ T cells with Aspergillus fumigatus in patients with chronic rhinosinusitis

Bacteria and fungi can exhibit superantigens regarding T cell activation. In chronic rhinosinusitis (CRS), local intranasal Staphylococcus aureus is known to be the most relevant superantigen, especially in patients with nasal polyps. Little is known about the role of Aspergillus fumigatus. The aim of the present study was to measure the influence of A. fumigatus on the activation of CD4+ and CD8+ T cells in patients with CRS.

Tissue and blood samples were collected from patients suffering from chronic rhinosinusitis with (n = 10) and without nasal polyps (n = 10) undergoing nasal sinus surgery. Additionally non-affected nasal tissue was obtained from 8 patients as control group. Tissue samples were dissociated and a cell sorting for CD4+ and CD8+ T cells was performed.. CD4+ and CD8+ cells were cultured together with antigen presenting cells (APC), respectively. A peptide pool with A. fumigatus was added to tissue and blood samples for 6 days. Afterwards, lymphocytes were separated and analyzed by multicolor flow cytometry. Activation was assessed by the proliferation marker Ki67.

All experiments were performed with the same concentration of A. fumigatus and for 6 days. No statistical differences on Ki67 expression were seen between peripheral blood lymphocytes and tissue samples in patients with CRSwNP or CRSsNP. A significantly higher activation of tissue CD4+ T cells was observed in CRSwNP compared to CRSsNP. No differences were measured between tissue CD8+ T cells of CRSwNP compared to CRSsNP.

In this study, a reproducible activation of CD4+ T cells by A. fumigatus was seen. These data indicate a direct influence of A. fumigatus on the maintenance of the inflammatory reaction in this disease.

Publikationsverlauf

Publikationsdatum:
23. April 2019 (online)