(384) Impact of elexacaftor/tezacaftor/ivacaftor therapy on the pathological reprogramming of lung-recruited neutrophils conditioned by cystic fibrosis airway fluid

Background: Cystic Fibrosis (CF) is caused by mutations of the CF transmembrane conductance regulator (CFTR) anion channel, leading to airway polymicrobial infections and neutrophilic inflammation. Prior studies from our group showed that blood neutrophils undergo metabolic, transcriptional and functional reprogramming upon entry into the CF lung lumen, leading to primary granule exocytosis, immune modulation of T-cells and macrophages, and metabolic licensing (dubbed the “GRIM” fate). While the advent of the elexacaftor/tezacaftor/ivacaftor (TRIKAFTA®, Vertex Pharmaceuticals) therapy directed at the CFTR channel has improved outcomes for patients with CF, it is unknown if and how it may impact neutrophil reprogramming in their lungs.

Methods: We previously showed that GRIM neutrophils can be mass-produced in an in vitro model [1], in which human blood neutrophils are recruited through a differentiated epithelial layer into CF airway supernatant (CFASN) purified from sputum of treatment-naïve patients. Here, we generated and tested the effect of airway supernatant from sputum of patients on elexacaftor/tezacaftor/ivacaftor modulators therapy (CFMOD) for comparison based on phenotyping (flow cytometry), functional (P. aeruginosa killing) and metabolomic (¹³C₆-glucose tracing) analyses of transmigrated neutrophils.

Results: CFMOD-recruited neutrophils contained ivacaftor, demonstrating exposure to the modulators (Figure 1). Compared to neutrophils recruited to a control chemoattractant (leukotriene B4), CFASN/CFMOD-recruited neutrophils showed enhanced primary granule exocytosis, decreased P. aeruginosa killing (with a slight improvement in CFMOD compared to CFASN condition), and increased AMP, GMP and metabolites related to citric acid cycle activity. ¹³C₆-glucose flux data showed similar rates of extracellular glucose utilization in all transmigration conditions, but higher total glycolysis to lactate in CFASN/CFMOD-transmigrated neutrophils.

Conclusions: Pathological reprogramming of neutrophils upon transmigration into CF airway fluid is not substantially altered by the use of elexacaftor/tezacaftor/ivacaftor modulators therapy. Ongoing transcriptional (RNA-Seq) and epigenetic (DNA methylation profiling) studies will bring further understanding onto this process and suggest potential targets for immunomodulatory therapy to be used as potential adjunct treatment to modulators therapy.

Acknowledgements:

Funding: NIH (R56 HL150658), CFF (CAMMAR21F0, TIROUV19A0), I3 Teams Research Award (Emory), CF@LANTA, a component of Emory University and Children’s Healthcare of Atlanta.

References: [1] Forrest O, Ingersoll S, Preininger M, Laval J, Limoli D, Brown M, Lee F, Bedi B, Sadikot R, Goldberg J, Tangpricha V, Gaggar A, Tirouvanziam R. Pathological conditioning of human neutrophils recruited to the airway milieu in cystic fibrosis. J Leukoc Biol. 2018 Oct;104(4):665-675. doi: 10.1002/JLB.5HI1117-454RR.