Enrichment of Cytomegalovirus-induced NKG2C+ Natural Killer Cells in the Lung Allograft. Issue 8 (August 2019)

• Record Type: Journal Article
• Authors: Harpur, Christopher M.; Stankovic, Sanda; Kanagarajah, Abbie; Widjaja, Jacqueline M.L.; Levvey, Bronwyn J.; Cristiano, Yvonne; Snell, Greg I.; Brooks, Andrew G.; Westall, Glen P.; Sullivan, Lucy C.
• Is Part Of: Transplantation. Volume 103:Issue 8(2019)
• Publication Date: 2019-08
• Subjects: Transplantation of organs, tissues, etc -- Periodicals; Transplantation immunology -- Periodicals; 617.95
• DOI: 10.1097/TP.0000000000002545
• Languages: English
• ISSNs: 0041-1337

Abstract

Abstract : Background: In lung transplant recipients, immunosuppressive medications result in impaired antiviral immunity and a propensity for cytomegalovirus (CMV) reactivation within the lung allograft. Natural killer (NK) cells play a key role in immunity to CMV, with an increase in the proportion of NK cells expressing activating CD94-NKG2C receptors in the blood being a strong correlate of CMV infection. Whether a similar increase in NKG2C + NK cells occurs in lung transplant recipients following CMV reactivation in the allograft and if such cells contribute to viral control remains unclear. Methods: In this pilot study, we longitudinally assessed the frequency and phenotype of NKG2C + NK cells in the blood and bronchoalveolar lavage (BAL) of lung transplant recipients and stratified recipients based on their risk of developing CMV disease. Results: We observed an increase in the proportion of NKG2C + NK cells in the blood and BAL of CMV high-risk patients, coincident with both the cessation of antiviral prophylaxis and subsequent detection of actively replicating CMV in the blood and lung allograft. Additionally, these NKG2C + NK cells expressed killer-cell immunoglobulin-like receptors distinct from those of other NK subsets and BAL NKG2C + NK cells possessed an activated phenotype. Finally, the frequency of NKG2C + NK cells in the BAL may be inversely correlated with CMV blood titers. Conclusions: Monitoring the phenotype of NK cells postlung transplant may be a useful biomarker for monitoring patient levels of CMV immunity.