Impaired calcineurin signaling in myeloid cells results in downregulation of pentraxin-3 and increased susceptibility to aspergillosis

Mucosal Immunol. 2017 Mar;10(2):470-480. doi: 10.1038/mi.2016.52. Epub 2016 Jun 15.

Abstract

Treatment of post-transplant patients with immunosuppressive drugs targeting the calcineurin-nuclear factor of activated T cells (NFAT) pathway, including cyclosporine A or tacrolimus, is commonly associated with a higher incidence of opportunistic infections, such as Aspergillus fumigatus, which can lead to severe life-threatening conditions. A component of the A. fumigatus cell wall, β-glucan, is recognized by dendritic cells (DCs) via the Dectin-1 receptor, triggering downstream signaling that leads to calcineurin-NFAT binding, NFAT translocation, and transcription of NFAT-regulated genes. Here, we address the question of whether calcineurin signaling in CD11c-expressing cells, such as DCs, has a specific role in the innate control of A. fumigatus. Impairment of calcineurin in CD11c-expressing cells (CD11ccrecnb1loxP) significantly increased susceptibility to systemic A. fumigatus infection and to intranasal infection in irradiated mice undergoing bone marrow transplant. Global expression profiling of bone marrow-derived DCs identified calcineurin-regulated processes in the immune response to infection, including expression of pentraxin-3, an important antifungal defense protein. These results suggest that calcineurin inhibition directly impairs important immunoprotective functions of myeloid cells, as shown by the higher susceptibility of CD11ccrecnbloxP mice in models of systemic and invasive pulmonary aspergillosis, including after allogeneic bone marrow transplantation. These findings are relevant to the clinical management of transplant patients with severe Aspergillus infections.

MeSH terms

  • Animals
  • Aspergillosis / immunology*
  • Aspergillus fumigatus / immunology*
  • Bone Marrow Transplantation*
  • C-Reactive Protein / genetics
  • C-Reactive Protein / metabolism*
  • CD11c Antigen / metabolism
  • Calcineurin / genetics
  • Calcineurin / metabolism*
  • Calcineurin Inhibitors / adverse effects
  • Calcineurin Inhibitors / therapeutic use
  • Cells, Cultured
  • Dendritic Cells / immunology*
  • Disease Susceptibility
  • Down-Regulation
  • Graft Rejection / prevention & control
  • Humans
  • Immunosuppressive Agents / adverse effects*
  • Immunosuppressive Agents / therapeutic use
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Serum Amyloid P-Component / genetics
  • Serum Amyloid P-Component / metabolism*
  • Signal Transduction

Substances

  • CD11c Antigen
  • Calcineurin Inhibitors
  • Immunosuppressive Agents
  • Serum Amyloid P-Component
  • PTX3 protein
  • C-Reactive Protein
  • Calcineurin