Poster Presentation Melbourne Immunotherapy Spring Symposium 2025

Investigating the effects of perioperatively administered therapies on postoperative immune status using spectral flow cytometry and high-dimensional analysis workflows (#135)

Yilei (Evelyn) Yang 1 2 , Joanne E. Davis 1 2 , Mandy Ludford-Menting 1 2 , Julia Dubowitz 3 , Bernhard Riedel 3 , David S. Ritchie 1 2 4 , Rachel Koldej 1 2
  1. ACRF Translational Research Laboratory, The Royal Melbourne Hospital, Melbourne, Victoria, Australia
  2. Department of Medicine, The University of Melbourne, Melbourne, Victoria, Australia
  3. Department of Anaesthesia, Peri-operative and Pain Medicine, Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
  4. Clinical Haematology, Peter MacCallum Cancer Centre and The Royal Melbourne Hospital, Melbourne, Victoria, Australia

Aim:

Postoperative natural killer (NK) cell dysfunction caused by surgical stress presents a window of opportunity for metastatic disease recurrence, driving the exploration of perioperative therapies to reduce surgically stressed NK cells. In this study, we used spectral flow cytometry to characterise the effect of perioperatively administrating seasonal influenza vaccine and arginine-enriched immunonutrition on postoperative NK cell function in cancer patients.

 

Method:

Patients were recruited prior to surgery to a phase 1 study investigating the impact of perioperative administration of seasonal influenza vaccine and arginine-enriched immunonutrition on perioperative immune status (PaSIVI). Peripheral blood mononuclear cells (PBMCs) were collected at three timepoints (baseline, postoperative day 1 and 5) from cancer surgery patients assigned to one of three treatment arms, control (n=4), vaccine only (n=3), and vaccine with arginine (n=4), with healthy donor PBMCs (n=2) included as controls. PBMCs were stained with a 31-colour spectral flow cytometry panel to identify immune cell subsets, and NK cell function was evaluated. Samples were acquired using the Cytek Aurora spectral flow cytometer and analysed on FlowJo, OMIQ, and GraphPad Prism software.

 

Results:

This study highlighted the effect of surgical stress on myeloid cells across all patient cohorts, wherein CD33+CD11b+HLA-DR- MDSCs significantly increased following surgery and reduced by postoperative day 5, whereas CD33+CD11b+HLA-DR+ monocytes followed the inverse trajectory. Functional analyses showed a trend of decreased NK function between baseline and postoperative day 1, and recovery by day 5.

 

Conclusion:

Immunophenotyping and NK functional assay results did not strongly support the efficacy of perioperative administration of seasonal influenza vaccine and arginine-enriched immunonutrition in preserving postoperative immune function. However, we illustrated the immunosuppressive effects of surgical stress, laying the groundwork for a more detailed pursuit of the perioperative immune status of cancer patients.